Core [omni.isaac.core]


Articulations

Articulation

class Articulation(prim_path: str, name: str = 'articulation', position: Optional[Sequence[float]] = None, translation: Optional[Sequence[float]] = None, orientation: Optional[Sequence[float]] = None, scale: Optional[Sequence[float]] = None, visible: Optional[bool] = None, articulation_controller: Optional[omni.isaac.core.controllers.articulation_controller.ArticulationController] = None, enable_dof_force_sensors: bool = False)

High level wrapper to deal with an articulation prim (only one articulation prim) and its attributes/properties.

Warning

The articulation object must be initialized in order to be able to operate on it. See the initialize method for more details.

Parameters
  • prim_path (str) – prim path of the Prim to encapsulate or create.

  • name (str, optional) – shortname to be used as a key by Scene class. Note: needs to be unique if the object is added to the Scene. Defaults to “articulation”.

  • position (Optional[Sequence[float]], optional) – position in the world frame of the prim. Shape is (3, ). Defaults to None, which means left unchanged.

  • translation (Optional[Sequence[float]], optional) – translation in the local frame of the prim (with respect to its parent prim). Shape is (3, ). Defaults to None, which means left unchanged.

  • orientation (Optional[Sequence[float]], optional) – quaternion orientation in the world/ local frame of the prim (depends if translation or position is specified). quaternion is scalar-first (w, x, y, z). Shape is (4, ). Defaults to None, which means left unchanged.

  • scale (Optional[Sequence[float]], optional) – local scale to be applied to the prim’s dimensions. Shape is (3, ). Defaults to None, which means left unchanged.

  • visible (bool, optional) – set to false for an invisible prim in the stage while rendering. Defaults to True.

  • articulation_controller (Optional[ArticulationController], optional) – a custom ArticulationController which inherits from it. Defaults to creating the basic ArticulationController.

  • enable_dof_force_sensors (bool, optional) – enables the solver computed dof force sensors on articulation joints. Defaults to False.

Example:

>>> import omni.isaac.core.utils.stage as stage_utils
>>> from omni.isaac.core.articulations import Articulation
>>>
>>> usd_path = "/home/<user>/Documents/Assets/Robots/Franka/franka_alt_fingers.usd"
>>> prim_path = "/World/envs/env_0/panda"
>>>
>>> # load the Franka Panda robot USD file
>>> stage_utils.add_reference_to_stage(usd_path, prim_path)
>>>
>>> # wrap the prim as an articulation
>>> prim = Articulation(prim_path=prim_path, name="franka_panda")
>>> prim
<omni.isaac.core.articulations.articulation.Articulation object at 0x7fdd165bf520>
apply_action(control_actions: omni.isaac.core.utils.types.ArticulationAction) None

Apply joint positions, velocities and/or efforts to control an articulation

Parameters
  • control_actions (ArticulationAction) – actions to be applied for next physics step.

  • indices (Optional[Union[list, np.ndarray]], optional) – degree of freedom indices to apply actions to. Defaults to all degrees of freedom.

Hint

High stiffness makes the joints snap faster and harder to the desired target, and higher damping smoothes but also slows down the joint’s movement to target

  • For position control, set relatively high stiffness and low damping (to reduce vibrations)

  • For velocity control, stiffness must be set to zero with a non-zero damping

  • For effort control, stiffness and damping must be set to zero

Example:

>>> from omni.isaac.core.utils.types import ArticulationAction
>>>
>>> # move all the robot joints to the indicated position
>>> action = ArticulationAction(joint_positions=np.array([0.0, -1.0, 0.0, -2.2, 0.0, 2.4, 0.8, 0.04, 0.04]))
>>> prim.apply_action(action)
>>>
>>> # close the robot fingers: panda_finger_joint1 (7) and panda_finger_joint2 (8) to 0.0
>>> action = ArticulationAction(joint_positions=np.array([0.0, 0.0]), joint_indices=np.array([7, 8]))
>>> prim.apply_action(action)
apply_visual_material(visual_material: omni.isaac.core.materials.visual_material.VisualMaterial, weaker_than_descendants: bool = False) None

Apply visual material to the held prim and optionally its descendants.

Parameters
  • visual_material (VisualMaterial) – visual material to be applied to the held prim. Currently supports PreviewSurface, OmniPBR and OmniGlass.

  • weaker_than_descendants (bool, optional) – True if the material shouldn’t override the descendants materials, otherwise False. Defaults to False.

Example:

>>> from omni.isaac.core.materials import OmniGlass
>>>
>>> # create a dark-red glass visual material
>>> material = OmniGlass(
...     prim_path="/World/material/glass",  # path to the material prim to create
...     ior=1.25,
...     depth=0.001,
...     thin_walled=False,
...     color=np.array([0.5, 0.0, 0.0])
... )
>>> prim.apply_visual_material(material)
property articulation_handle: int

A handler to the articulation

The handler is a unique identifier used by the Dynamic Control extension to manage the articulation

Returns

handle

Return type

int

Example:

>>> prim.articulation_handle
1116691496961
disable_gravity() None

Keep gravity from affecting the robot

Example:

>>> prim.disable_gravity()
property dof_names: List[str]

List of prim names for each DOF.

Returns

prim names

Return type

list(string)

Example:

>>> prim.dof_names
['panda_joint1', 'panda_joint2', 'panda_joint3', 'panda_joint4', 'panda_joint5',
 'panda_joint6', 'panda_joint7', 'panda_finger_joint1', 'panda_finger_joint2']
property dof_properties: numpy.ndarray

Articulation DOF properties

DOF properties

Index

Property name

Description

0

type

DOF type: invalid/unknown/uninitialized (0), rotation (1), translation (2)

1

hasLimits

Whether the DOF has limits

2

lower

Lower DOF limit (in radians or meters)

3

upper

Upper DOF limit (in radians or meters)

4

driveMode

Drive mode for the DOF: force (1), acceleration (2)

5

maxVelocity

Maximum DOF velocity. In radians/s, or stage_units/s

6

maxEffort

Maximum DOF effort. In N or N*stage_units

7

stiffness

DOF stiffness

8

damping

DOF damping

Returns

named NumPy array of shape (num_dof, 9)

Return type

np.ndarray

Example:

>>> # get properties for all DOFs
>>> prim.dof_properties
[(1,  True, -2.8973,  2.8973, 1, 1.0000000e+01, 5220., 60000., 3000.)
 (1,  True, -1.7628,  1.7628, 1, 1.0000000e+01, 5220., 60000., 3000.)
 (1,  True, -2.8973,  2.8973, 1, 5.9390470e+36, 5220., 60000., 3000.)
 (1,  True, -3.0718, -0.0698, 1, 5.9390470e+36, 5220., 60000., 3000.)
 (1,  True, -2.8973,  2.8973, 1, 5.9390470e+36,  720., 25000., 3000.)
 (1,  True, -0.0175,  3.7525, 1, 5.9390470e+36,  720., 15000., 3000.)
 (1,  True, -2.8973,  2.8973, 1, 1.0000000e+01,  720.,  5000., 3000.)
 (2,  True,  0.    ,  0.04  , 1, 3.4028235e+38,  720.,  6000., 1000.)
 (2,  True,  0.    ,  0.04  , 1, 3.4028235e+38,  720.,  6000., 1000.)]
>>>
>>> # property names
>>> prim.dof_properties.dtype.names
('type', 'hasLimits', 'lower', 'upper', 'driveMode', 'maxVelocity', 'maxEffort', 'stiffness', 'damping')
>>>
>>> # get DOF upper limits
>>> prim.dof_properties["upper"]
[ 2.8973  1.7628  2.8973 -0.0698  2.8973  3.7525  2.8973  0.04    0.04  ]
>>>
>>> # get the last DOF (panda_finger_joint2) upper limit
>>> prim.dof_properties["upper"][8]  # or prim.dof_properties[8][3]
0.04
enable_gravity() None

Gravity will affect the robot

Example:

>>> prim.enable_gravity()
get_angular_velocity() numpy.ndarray

Get the angular velocity of the root articulation prim

Returns

3D angular velocity vector. Shape (3,)

Return type

np.ndarray

Example:

>>> prim.get_angular_velocity()
[0. 0. 0.]
get_applied_action() omni.isaac.core.utils.types.ArticulationAction

Get the last applied action

Returns

last applied action. Note: a dictionary is used as the object’s string representation

Return type

ArticulationAction

Example:

>>> # last applied action: joint_positions -> [0.0, -1.0, 0.0, -2.2, 0.0, 2.4, 0.8, 0.04, 0.04]
>>> prim.get_applied_action()
{'joint_positions': [0.0, -1.0, 0.0, -2.200000047683716, 0.0, 2.4000000953674316,
                     0.800000011920929, 0.03999999910593033, 0.03999999910593033],
 'joint_velocities': [0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0],
 'joint_efforts': [0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0]}
get_applied_joint_efforts(joint_indices: Optional[Union[List, numpy.ndarray]] = None) numpy.ndarray

Get the efforts applied to the joints set by the set_joint_efforts method

Parameters

joint_indices (Optional[Union[List, np.ndarray]], optional) – indices to specify which joints to read. Defaults to None (all joints)

Raises

Exception – If the handlers are not initialized

Returns

all or selected articulation joint applied efforts

Return type

np.ndarray

Example:

>>> # get all applied joint efforts
>>> prim.get_applied_joint_efforts()
[ 0.  0.  0.  0.  0.  0.  0.  0.  0.]
>>>
>>> # get finger applied efforts: panda_finger_joint1 (7) and panda_finger_joint2 (8)
>>> prim.get_applied_joint_efforts(joint_indices=np.array([7, 8]))
[0.  0.]
get_applied_visual_material() omni.isaac.core.materials.visual_material.VisualMaterial

Return the current applied visual material in case it was applied using apply_visual_material or it’s one of the following materials that was already applied before: PreviewSurface, OmniPBR and OmniGlass.

Returns

the current applied visual material if its type is currently supported.

Return type

VisualMaterial

Example:

>>> # given a visual material applied
>>> prim.get_applied_visual_material()
<omni.isaac.core.materials.omni_glass.OmniGlass object at 0x7f36263106a0>
get_articulation_body_count() int

Get the number of bodies (links) that make up the articulation

Returns

amount of bodies

Return type

int

Example:

>>> prim.get_articulation_body_count()
12
get_articulation_controller() omni.isaac.core.controllers.articulation_controller.ArticulationController

Get the articulation controller

Note

If no articulation_controller was passed during class instantiation, a default controller of type ArticulationController (a Proportional-Derivative controller that can apply position targets, velocity targets and efforts) will be used

Returns

articulation controller

Return type

ArticulationController

Example:

>>> prim.get_articulation_controller()
<omni.isaac.core.controllers.articulation_controller.ArticulationController object at 0x7f04a0060190>
get_default_state() omni.isaac.core.utils.types.XFormPrimState

Get the default prim states (spatial position and orientation).

Returns

an object that contains the default state of the prim (position and orientation)

Return type

XFormPrimState

Example:

>>> state = prim.get_default_state()
>>> state
<omni.isaac.core.utils.types.XFormPrimState object at 0x7f33addda650>
>>>
>>> state.position
[-4.5299529e-08 -1.8347054e-09 -2.8610229e-08]
>>> state.orientation
[1. 0. 0. 0.]
get_dof_index(dof_name: str) int

Get a DOF index given its name

Parameters

dof_name (str) – name of the DOF

Returns

DOF index

Return type

int

Example:

>>> prim.get_dof_index("panda_finger_joint2")
8
get_enabled_self_collisions() int

Get the enable self collisions flag (physxArticulation:enabledSelfCollisions)

Returns

self collisions flag (boolean interpreted as int)

Return type

int

Example:

>>> prim.get_enabled_self_collisions()
0
get_joint_positions(joint_indices: Optional[Union[List, numpy.ndarray]] = None) numpy.ndarray

Get the articulation joint positions

Parameters

joint_indices (Optional[Union[List, np.ndarray]], optional) – indices to specify which joints to read. Defaults to None (all joints)

Returns

all or selected articulation joint positions

Return type

np.ndarray

Example:

>>> # get all joint positions
>>> prim.get_joint_positions()
[ 1.1999920e-02 -5.6962633e-01  1.3480479e-08 -2.8105433e+00  6.8284894e-06
  3.0301569e+00  7.3234749e-01  3.9912373e-02  3.9999999e-02]
>>>
>>> # get finger positions: panda_finger_joint1 (7) and panda_finger_joint2 (8)
>>> prim.get_joint_positions(joint_indices=np.array([7, 8]))
[0.03991237  3.9999999e-02]
get_joint_velocities(joint_indices: Optional[Union[List, numpy.ndarray]] = None) numpy.ndarray

Get the articulation joint velocities

Parameters

joint_indices (Optional[Union[List, np.ndarray]], optional) – indices to specify which joints to read. Defaults to None (all joints)

Returns

all or selected articulation joint velocities

Return type

np.ndarray

Example:

>>> # get all joint velocities
>>> prim.get_joint_velocities()
[ 1.91603772e-06 -7.67638255e-03 -2.19138826e-07  1.10636465e-02 -4.63412944e-05
  3.48245539e-02  8.84692147e-02  5.40335372e-04 1.02849208e-05]
>>>
>>> # get finger velocities: panda_finger_joint1 (7) and panda_finger_joint2 (8)
>>> prim.get_joint_velocities(joint_indices=np.array([7, 8]))
[5.4033537e-04 1.0284921e-05]
get_joints_default_state() omni.isaac.core.utils.types.JointsState

Get the default joint states (positions and velocities).

Returns

an object that contains the default joint positions and velocities

Return type

JointsState

Example:

>>> state = prim.get_joints_default_state()
>>> state
<omni.isaac.core.utils.types.JointsState object at 0x7f04a0061240>
>>>
>>> state.positions
[ 0.012  -0.57000005  0.  -2.81  0.  3.037  0.785398  0.04  0.04 ]
>>> state.velocities
[0. 0. 0. 0. 0. 0. 0. 0. 0.]
get_joints_state() omni.isaac.core.utils.types.JointsState

Get the current joint states (positions and velocities)

Returns

an object that contains the current joint positions and velocities

Return type

JointsState

Example:

>>> state = prim.get_joints_state()
>>> state
<omni.isaac.core.utils.types.JointsState object at 0x7f02f6df57b0>
>>>
>>> state.positions
[ 1.1999920e-02 -5.6962633e-01  1.3480479e-08 -2.8105433e+00 6.8284894e-06
  3.0301569e+00  7.3234749e-01  3.9912373e-02  3.9999999e-02]
>>> state.velocities
[ 1.91603772e-06 -7.67638255e-03 -2.19138826e-07  1.10636465e-02 -4.63412944e-05
  245539e-02  8.84692147e-02  5.40335372e-04  1.02849208e-05]
get_linear_velocity() numpy.ndarray

Get the linear velocity of the root articulation prim

Returns

3D linear velocity vector. Shape (3,)

Return type

np.ndarray

Example:

>>> prim.get_linear_velocity()
[0. 0. 0.]
get_local_pose() Tuple[numpy.ndarray, numpy.ndarray]

Get prim’s pose with respect to the local frame (the prim’s parent frame)

Returns

first index is the position in the local frame (with shape (3, )). Second index is quaternion orientation (with shape (4, )) in the local frame

Return type

Tuple[np.ndarray, np.ndarray]

Example:

>>> # if the prim is in position (1.0, 0.5, 0.0) with respect to the world frame
>>> position, orientation = prim.get_local_pose()
>>> position
[0. 0. 0.]
>>> orientation
[0. 0. 0.]
get_local_scale() numpy.ndarray

Get prim’s scale with respect to the local frame (the parent’s frame)

Returns

scale applied to the prim’s dimensions in the local frame. shape is (3, ).

Return type

np.ndarray

Example:

>>> prim.get_local_scale()
[1. 1. 1.]
get_measured_joint_efforts(joint_indices: Optional[Union[List, numpy.ndarray]] = None) numpy.ndarray

Returns the efforts computed/measured by the physics solver of the joint forces in the DOF motion direction

Parameters

joint_indices (Optional[Union[List, np.ndarray]], optional) – indices to specify which joints to read. Defaults to None (all joints)

Raises

Exception – If the handlers are not initialized

Returns

all or selected articulation joint measured efforts

Return type

np.ndarray

Example:

>>> # get all joint efforts
>>> prim.get_measured_joint_efforts()
[ 2.7897308e-06 -6.9083519e+00 -3.6398471e-06  1.9158335e+01 -4.3552645e-06
  1.1866090e+00 -4.7079347e-06  3.2339853e-04 -3.2044132e-04]
>>>
>>> # get finger efforts: panda_finger_joint1 (7) and panda_finger_joint2 (8)
>>> prim.get_measured_joint_efforts(joint_indices=np.array([7, 8]))
[ 0.0003234  -0.00032044]
get_measured_joint_forces(joint_indices: Optional[Union[List, numpy.ndarray]] = None) numpy.ndarray

Get the measured joint reaction forces and torques (link incoming joint forces and torques) to external loads

Note

Since the name->index map for joints has not been exposed yet, it is possible to access the joint names and their indices through the articulation metadata.

prim._articulation_view._metadata.joint_names  # list of names
prim._articulation_view._metadata.joint_indices  # dict of name: index

To retrieve a specific row for the link incoming joint force/torque use joint_index + 1

Parameters

joint_indices (Optional[Union[List, np.ndarray]], optional) – indices to specify which joints to read. Defaults to None (all joints)

Raises

Exception – If the handlers are not initialized

Returns

measured joint forces and torques. Shape is (num_joint + 1, 6). Row index 0 is the incoming joint of the base link. For the last dimension the first 3 values are for forces and the last 3 for torques

Return type

np.ndarray

Example:

>>> # get all measured joint forces and torques
>>> prim.get_measured_joint_forces()
[[ 0.0000000e+00  0.0000000e+00  0.0000000e+00  0.0000000e+00  0.0000000e+00  0.0000000e+00]
 [ 1.4995076e+02  4.2574748e-06  5.6364370e-04  4.8701895e-05 -6.9072924e+00  3.1881387e-05]
 [-2.8971717e-05 -1.0677823e+02 -6.8384506e+01 -6.9072924e+00 -5.4927128e-05  6.1222494e-07]
 [ 8.7120995e+01 -4.3871860e-05 -5.5795174e+01  5.3687054e-05 -2.4538563e+01  1.3333466e-05]
 [ 5.3519474e-05 -4.8109909e+01  6.0709282e+01  1.9157074e+01 -5.9258469e-05  8.2744418e-07]
 [-3.1691040e+01  2.3313689e-04  3.9990173e+01 -5.8968733e-05 -1.1863431e+00  2.2335558e-05]
 [-1.0809851e-04  1.5340537e+01 -1.5458489e+01  1.1863426e+00  6.1094368e-05 -1.5940281e-05]
 [-7.5418940e+00 -5.0814648e+00 -5.6512990e+00 -5.6385466e-05  3.8859999e-01 -3.4943256e-01]
 [ 4.7421460e+00 -3.1945827e+00  3.5528181e+00  5.5852943e-05  8.4794536e-03  7.6405057e-03]
 [ 4.0760727e+00  2.1640673e-01 -4.0513167e+00 -5.9565349e-04  1.1407082e-02  2.1432268e-06]
 [ 5.1680198e-03 -9.7754575e-02 -9.7093947e-02 -8.4155556e-12 -1.2910691e-12 -1.9347857e-11]
 [-5.1910793e-03  9.7588278e-02 -9.7106412e-02  8.4155573e-12  1.2910637e-12 -1.9347855e-11]]
>>>
>>> # get measured joint force and torque for the fingers
>>> metadata = prim._articulation_view._metadata
>>> joint_indices = 1 + np.array([
...     metadata.joint_indices["panda_finger_joint1"],
...     metadata.joint_indices["panda_finger_joint2"],
... ])
>>> joint_indices
[10 11]
>>> prim.get_measured_joint_forces(joint_indices)
[[ 5.1680198e-03 -9.7754575e-02 -9.7093947e-02 -8.4155556e-12 -1.2910691e-12 -1.9347857e-11]
 [-5.1910793e-03  9.7588278e-02 -9.7106412e-02  8.4155573e-12  1.2910637e-12 -1.9347855e-11]]
get_sleep_threshold() float

Get the threshold for articulations to enter a sleep state

Search for Articulations and Sleeping in PhysX docs for more details

Returns

sleep threshold

Return type

float

Example:

>>> prim.get_sleep_threshold()
0.005
get_solver_position_iteration_count() int

Get the solver (position) iteration count for the articulation

The solver iteration count determines how accurately contacts, drives, and limits are resolved. Search for Solver Iteration Count in PhysX docs for more details.

Returns

position iteration count

Return type

int

Example:

>>> prim.get_solver_position_iteration_count()
32
get_solver_velocity_iteration_count() int

Get the solver (velocity) iteration count for the articulation

The solver iteration count determines how accurately contacts, drives, and limits are resolved. Search for Solver Iteration Count in PhysX docs for more details.

Returns

velocity iteration count

Return type

int

Example:

>>> prim.get_solver_velocity_iteration_count()
32
get_stabilization_threshold() float

Get the mass-normalized kinetic energy below which the articulation may participate in stabilization

Search for Stabilization Threshold in PhysX docs for more details

Returns

stabilization threshold

Return type

float

Example:

>>> prim.get_stabilization_threshold()
0.0009999999
get_visibility() bool
Returns

true if the prim is visible in stage. false otherwise.

Return type

bool

Example:

>>> # get the visible state of an visible prim on the stage
>>> prim.get_visibility()
True
get_world_pose() Tuple[numpy.ndarray, numpy.ndarray]

Get prim’s pose with respect to the world’s frame

Returns

first index is the position in the world frame (with shape (3, )). Second index is quaternion orientation (with shape (4, )) in the world frame

Return type

Tuple[np.ndarray, np.ndarray]

Example:

>>> # if the prim is in position (1.0, 0.5, 0.0) with respect to the world frame
>>> position, orientation = prim.get_world_pose()
>>> position
[1.  0.5 0. ]
>>> orientation
[1. 0. 0. 0.]
get_world_scale() numpy.ndarray

Get prim’s scale with respect to the world’s frame

Returns

scale applied to the prim’s dimensions in the world frame. shape is (3, ).

Return type

np.ndarray

Example:

>>> prim.get_world_scale()
[1. 1. 1.]
property handles_initialized: bool

Check if articulation handler is initialized

Returns

whether the handler was initialized

Return type

bool

Example:

>>> prim.handles_initialized
True
initialize(physics_sim_view: Optional[omni.physics.tensors.bindings._physicsTensors.SimulationView] = None) None

Create a physics simulation view if not passed and an articulation view using PhysX tensor API

Note

If the articulation has been added to the world scene (e.g., world.scene.add(prim)), it will be automatically initialized when the world is reset (e.g., world.reset()).

Warning

This method needs to be called after each hard reset (e.g., Stop + Play on the timeline) before interacting with any other class method.

Parameters

physics_sim_view (omni.physics.tensors.SimulationView, optional) – current physics simulation view. Defaults to None.

Example:

>>> prim.initialize()
is_valid() bool

Check if the prim path has a valid USD Prim at it

Returns

True is the current prim path corresponds to a valid prim in stage. False otherwise.

Return type

bool

Example:

>>> # given an existing and valid prim
>>> prims.is_valid()
True
is_visual_material_applied() bool

Check if there is a visual material applied

Returns

True if there is a visual material applied. False otherwise.

Return type

bool

Example:

>>> # given a visual material applied
>>> prim.is_visual_material_applied()
True
property name: Optional[str]

Returns: str: name given to the prim when instantiating it. Otherwise None.

Used to query if the prim is a non root articulation link

Returns

True if the prim itself is a non root link

Return type

bool

Example:

>>> # for a wrapped articulation (where the root prim has the Physics Articulation Root property applied)
>>> prim.non_root_articulation_link
False
property num_dof: int

Number of DOF of the articulation

Returns

amount of DOFs

Return type

int

Example:

>>> prim.num_dof
9
post_reset() None

Reset the prim to its default state (position and orientation).

Note

For an articulation, in addition to configuring the root prim’s default position and spatial orientation (defined via the set_default_state method), the joint’s positions, velocities, and efforts (defined via the set_joints_default_state method) are imposed

Example:

>>> prim.post_reset()
property prim: pxr.Usd.Prim

Returns: Usd.Prim: USD Prim object that this object holds.

property prim_path: str

Returns: str: prim path in the stage

set_angular_velocity(velocity: numpy.ndarray) None

Set the angular velocity of the root articulation prim

Warning

This method will immediately set the articulation state

Parameters

velocity (np.ndarray) – 3D angular velocity vector. Shape (3,)

Hint

This method belongs to the methods used to set the articulation kinematic state:

set_linear_velocity, set_angular_velocity, set_joint_positions, set_joint_velocities, set_joint_efforts

Example:

>>> prim.set_angular_velocity(np.array([0.1, 0.0, 0.0]))
set_default_state(position: Optional[Sequence[float]] = None, orientation: Optional[Sequence[float]] = None) None

Set the default state of the prim (position and orientation), that will be used after each reset.

Parameters
  • position (Optional[Sequence[float]], optional) – position in the world frame of the prim. shape is (3, ). Defaults to None, which means left unchanged.

  • orientation (Optional[Sequence[float]], optional) – quaternion orientation in the world frame of the prim. quaternion is scalar-first (w, x, y, z). shape is (4, ). Defaults to None, which means left unchanged.

Example:

>>> # configure default state
>>> prim.set_default_state(position=np.array([1.0, 0.5, 0.0]), orientation=np.array([1, 0, 0, 0]))
>>>
>>> # set default states during post-reset
>>> prim.post_reset()
set_enabled_self_collisions(flag: bool) None

Set the enable self collisions flag (physxArticulation:enabledSelfCollisions)

Parameters

flag (bool) – whether to enable self collisions

Example:

>>> prim.set_enabled_self_collisions(True)
set_joint_efforts(efforts: numpy.ndarray, joint_indices: Optional[Union[List, numpy.ndarray]] = None) None

Set the articulation joint efforts

Note

This method can be used for effort control. For this purpose, there must be no joint drive or the stiffness and damping must be set to zero.

Parameters
  • efforts (np.ndarray) – articulation joint efforts

  • joint_indices (Optional[Union[list, np.ndarray]], optional) – indices to specify which joints to manipulate. Defaults to None (all joints)

Hint

This method belongs to the methods used to set the articulation kinematic state:

set_linear_velocity, set_angular_velocity, set_joint_positions, set_joint_velocities, set_joint_efforts

Example:

>>> # set all the robot joint efforts to 0.0
>>> prim.set_joint_efforts(np.array([0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0]))
>>>
>>> # set only the fingers efforts: panda_finger_joint1 (7) and panda_finger_joint2 (8) to 10
>>> prim.set_joint_efforts(np.array([10, 10]), joint_indices=np.array([7, 8]))
set_joint_positions(positions: numpy.ndarray, joint_indices: Optional[Union[List, numpy.ndarray]] = None) None

Set the articulation joint positions

Warning

This method will immediately set (teleport) the affected joints to the indicated value. Use the apply_action method to control robot joints.

Parameters
  • positions (np.ndarray) – articulation joint positions

  • joint_indices (Optional[Union[list, np.ndarray]], optional) – indices to specify which joints to manipulate. Defaults to None (all joints)

Hint

This method belongs to the methods used to set the articulation kinematic state:

set_linear_velocity, set_angular_velocity, set_joint_positions, set_joint_velocities, set_joint_efforts

Example:

>>> # set all the robot joints
>>> prim.set_joint_positions(np.array([0.0, -1.0, 0.0, -2.2, 0.0, 2.4, 0.8, 0.04, 0.04]))
>>>
>>> # set only the fingers in closed position: panda_finger_joint1 (7) and panda_finger_joint2 (8) to 0.0
>>> prim.set_joint_positions(np.array([0.04, 0.04]), joint_indices=np.array([7, 8]))
set_joint_velocities(velocities: numpy.ndarray, joint_indices: Optional[Union[List, numpy.ndarray]] = None) None

Set the articulation joint velocities

Warning

This method will immediately set the affected joints to the indicated value. Use the apply_action method to control robot joints.

Parameters
  • velocities (np.ndarray) – articulation joint velocities

  • joint_indices (Optional[Union[list, np.ndarray]], optional) – indices to specify which joints to manipulate. Defaults to None (all joints)

Hint

This method belongs to the methods used to set the articulation kinematic state:

set_linear_velocity, set_angular_velocity, set_joint_positions, set_joint_velocities, set_joint_efforts

Example:

>>> # set all the robot joint velocities to 0.0
>>> prim.set_joint_velocities(np.array([0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0]))
>>>
>>> # set only the fingers velocities: panda_finger_joint1 (7) and panda_finger_joint2 (8) to -0.01
>>> prim.set_joint_velocities(np.array([-0.01, -0.01]), joint_indices=np.array([7, 8]))
set_joints_default_state(positions: Optional[numpy.ndarray] = None, velocities: Optional[numpy.ndarray] = None, efforts: Optional[numpy.ndarray] = None) None

Set the joint default states (positions, velocities and/or efforts) to be applied after each reset.

Note

The default states will be set during post-reset (e.g., calling .post_reset() or world.reset() methods)

Parameters
  • positions (Optional[np.ndarray], optional) – joint positions. Defaults to None.

  • velocities (Optional[np.ndarray], optional) – joint velocities. Defaults to None.

  • efforts (Optional[np.ndarray], optional) – joint efforts. Defaults to None.

Example:

>>> # configure default joint states
>>> prim.set_joints_default_state(
...     positions=np.array([0.0, -1.0, 0.0, -2.2, 0.0, 2.4, 0.8, 0.04, 0.04]),
...     velocities=np.zeros(shape=(prim.num_dof,)),
...     efforts=np.zeros(shape=(prim.num_dof,))
... )
>>>
>>> # set default states during post-reset
>>> prim.post_reset()
set_linear_velocity(velocity: numpy.ndarray) None

Set the linear velocity of the root articulation prim

Warning

This method will immediately set the articulation state

Parameters

velocity (np.ndarray) – 3D linear velocity vector. Shape (3,).

Hint

This method belongs to the methods used to set the articulation kinematic state:

set_linear_velocity, set_angular_velocity, set_joint_positions, set_joint_velocities, set_joint_efforts

Example:

>>> prim.set_linear_velocity(np.array([0.1, 0.0, 0.0]))
set_local_pose(translation: Optional[Sequence[float]] = None, orientation: Optional[Sequence[float]] = None) None

Set prim’s pose with respect to the local frame (the prim’s parent frame).

Warning

This method will change (teleport) the prim pose immediately to the indicated value

Parameters
  • translation (Optional[Sequence[float]], optional) – translation in the local frame of the prim (with respect to its parent prim). shape is (3, ). Defaults to None, which means left unchanged.

  • orientation (Optional[Sequence[float]], optional) – quaternion orientation in the local frame of the prim. quaternion is scalar-first (w, x, y, z). shape is (4, ). Defaults to None, which means left unchanged.

Hint

This method belongs to the methods used to set the prim state

Example:

>>> prim.set_local_pose(translation=np.array([1.0, 0.5, 0.0]), orientation=np.array([1., 0., 0., 0.]))
set_local_scale(scale: Optional[Sequence[float]]) None

Set prim’s scale with respect to the local frame (the prim’s parent frame).

Parameters

scale (Optional[Sequence[float]]) – scale to be applied to the prim’s dimensions. shape is (3, ). Defaults to None, which means left unchanged.

Example:

>>> # scale prim 10 times smaller
>>> prim.set_local_scale(np.array([0.1, 0.1, 0.1]))
set_sleep_threshold(threshold: float) None

Set the threshold for articulations to enter a sleep state

Search for Articulations and Sleeping in PhysX docs for more details

Parameters

threshold (float) – sleep threshold

Example:

>>> prim.set_sleep_threshold(0.01)
set_solver_position_iteration_count(count: int) None

Set the solver (position) iteration count for the articulation

The solver iteration count determines how accurately contacts, drives, and limits are resolved. Search for Solver Iteration Count in PhysX docs for more details.

Warning

Setting a higher number of iterations may improve the fidelity of the simulation, although it may affect its performance.

Parameters

count (int) – position iteration count

Example:

>>> prim.set_solver_position_iteration_count(64)
set_solver_velocity_iteration_count(count: int)

Set the solver (velocity) iteration count for the articulation

The solver iteration count determines how accurately contacts, drives, and limits are resolved. Search for Solver Iteration Count in PhysX docs for more details.

Warning

Setting a higher number of iterations may improve the fidelity of the simulation, although it may affect its performance.

Parameters

count (int) – velocity iteration count

Example:

>>> prim.set_solver_velocity_iteration_count(64)
set_stabilization_threshold(threshold: float) None

Set the mass-normalized kinetic energy below which the articulation may participate in stabilization

Search for Stabilization Threshold in PhysX docs for more details

Parameters

threshold (float) – stabilization threshold

Example:

>>> prim.set_stabilization_threshold(0.005)
set_visibility(visible: bool) None

Set the visibility of the prim in stage

Parameters

visible (bool) – flag to set the visibility of the usd prim in stage.

Example:

>>> # make prim not visible in the stage
>>> prim.set_visibility(visible=False)
set_world_pose(position: Optional[Sequence[float]] = None, orientation: Optional[Sequence[float]] = None) None

Ses prim’s pose with respect to the world’s frame

Warning

This method will change (teleport) the prim pose immediately to the indicated value

Parameters
  • position (Optional[Sequence[float]], optional) – position in the world frame of the prim. shape is (3, ). Defaults to None, which means left unchanged.

  • orientation (Optional[Sequence[float]], optional) – quaternion orientation in the world frame of the prim. quaternion is scalar-first (w, x, y, z). shape is (4, ). Defaults to None, which means left unchanged.

Hint

This method belongs to the methods used to set the prim state

Example:

>>> prim.set_world_pose(position=np.array([1.0, 0.5, 0.0]), orientation=np.array([1., 0., 0., 0.]))

ArticulationView

class ArticulationView(prim_paths_expr: str, name: str = 'articulation_prim_view', positions: Optional[Union[numpy.ndarray, torch.Tensor, warp.types.array]] = None, translations: Optional[Union[numpy.ndarray, torch.Tensor, warp.types.array]] = None, orientations: Optional[Union[numpy.ndarray, torch.Tensor, warp.types.array]] = None, scales: Optional[Union[numpy.ndarray, torch.Tensor, warp.types.array]] = None, visibilities: Optional[Union[numpy.ndarray, torch.Tensor, warp.types.array]] = None, reset_xform_properties: bool = True, enable_dof_force_sensors: bool = False)

High level wrapper to deal with prims (one or many) that have the Root Articulation API applied and their attributes/properties

This class wraps all matching articulations found at the regex provided at the prim_paths_expr argument

Note

Each prim will have xformOp:orient, xformOp:translate and xformOp:scale only post-init, unless it is a non-root articulation link.

Warning

The articulation view object must be initialized in order to be able to operate on it. See the initialize method for more details.

Parameters
  • prim_paths_expr (str) – prim paths regex to encapsulate all prims that match it. example: “/World/Env[1-5]/Franka” will match /World/Env1/Franka, /World/Env2/Franka..etc. (a non regex prim path can also be used to encapsulate one rigid prim).

  • name (str, optional) – shortname to be used as a key by Scene class. Note: needs to be unique if the object is added to the Scene. Defaults to “articulation_prim_view”.

  • positions (Optional[Union[np.ndarray, torch.Tensor, wp.array]], optional) – default positions in the world frame of the prims. shape is (N, 3). Defaults to None, which means left unchanged.

  • translations (Optional[Union[np.ndarray, torch.Tensor, wp.array]], optional) – default translations in the local frame of the prims (with respect to its parent prims). shape is (N, 3). Defaults to None, which means left unchanged.

  • orientations (Optional[Union[np.ndarray, torch.Tensor, wp.array]], optional) – default quaternion orientations in the world/ local frame of the prims (depends if translation or position is specified). quaternion is scalar-first (w, x, y, z). shape is (N, 4).

  • scales (Optional[Union[np.ndarray, torch.Tensor, wp.array]], optional) – local scales to be applied to the prim’s dimensions in the view. shape is (N, 3). Defaults to None, which means left unchanged.

  • visibilities (Optional[Union[np.ndarray, torch.Tensor, wp.array]], optional) – set to false for an invisible prim in the stage while rendering. shape is (N,). Defaults to None.

  • reset_xform_properties (bool, optional) – True if the prims don’t have the right set of xform properties (i.e: translate, orient and scale) ONLY and in that order. Set this parameter to False if the object were cloned using using the cloner api in omni.isaac.cloner. Defaults to True.

  • enable_dof_force_sensors (bool, optional) – enables the solver computed dof force sensors on articulation joints. Defaults to False.

Example:

>>> import omni.isaac.core.utils.stage as stage_utils
>>> from omni.isaac.cloner import GridCloner
>>> from omni.isaac.core.articulations import ArticulationView
>>> from pxr import UsdGeom
>>>
>>> usd_path = "/home/<user>/Documents/Assets/Robots/Franka/franka_alt_fingers.usd"
>>> env_zero_path = "/World/envs/env_0"
>>> num_envs = 5
>>>
>>> # load the Franka Panda robot USD file
>>> stage_utils.add_reference_to_stage(usd_path, prim_path=f"{env_zero_path}/panda")  # /World/envs/env_0/panda
>>>
>>> # clone the environment (num_envs)
>>> cloner = GridCloner(spacing=1.5)
>>> cloner.define_base_env(env_zero_path)
>>> UsdGeom.Xform.Define(stage_utils.get_current_stage(), env_zero_path)
>>> cloner.clone(source_prim_path=env_zero_path, prim_paths=cloner.generate_paths("/World/envs/env", num_envs))
>>>
>>> # wrap all articulations
>>> prims = ArticulationView(prim_paths_expr="/World/envs/env.*/panda", name="franka_panda_view")
>>> prims
<omni.isaac.core.articulations.articulation_view.ArticulationView object at 0x7ff174054b20>
apply_action(control_actions: omni.isaac.core.utils.types.ArticulationActions, indices: Optional[Union[numpy.ndarray, List, torch.Tensor, warp.types.array]] = None) None

Apply joint positions (targets), velocities (targets) and/or efforts to control an articulation

Note

This method can be used instead of the separate set_joint_position_targets, set_joint_velocity_targets and set_joint_efforts

Parameters
  • control_actions (ArticulationActions) – actions to be applied for next physics step.

  • indices (Optional[Union[np.ndarray, List, torch.Tensor, wp.array]], optional) – indices to specify which prims to manipulate. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

Hint

High stiffness makes the joints snap faster and harder to the desired target, and higher damping smoothes but also slows down the joint’s movement to target

  • For position control, set relatively high stiffness and low damping (to reduce vibrations)

  • For velocity control, stiffness must be set to zero with a non-zero damping

  • For effort control, stiffness and damping must be set to zero

Example:

>>> from omni.isaac.core.utils.types import ArticulationActions
>>>
>>> # move all the articulation joints to the indicated position.
>>> # Since there are 5 envs, the joint positions are repeated 5 times
>>> positions = np.tile(np.array([0.0, -1.0, 0.0, -2.2, 0.0, 2.4, 0.8, 0.04, 0.04]), (num_envs, 1))
>>> action = ArticulationActions(joint_positions=positions)
>>> prims.apply_action(action)
>>>
>>> # close the robot fingers: panda_finger_joint1 (7) and panda_finger_joint2 (8) to 0.0
>>> # for the first, middle and last of the 5 envs
>>> positions = np.tile(np.array([0.0, 0.0]), (3, 1))
>>> action = ArticulationActions(joint_positions=positions, joint_indices=np.array([7, 8]))
>>> prims.apply_action(action, indices=np.array([0, 2, 4]))
apply_visual_materials(visual_materials: Union[omni.isaac.core.materials.visual_material.VisualMaterial, List[omni.isaac.core.materials.visual_material.VisualMaterial]], weaker_than_descendants: Optional[Union[bool, List[bool]]] = None, indices: Optional[Union[numpy.ndarray, list, torch.Tensor, warp.types.array]] = None) None

Apply visual material to the prims and optionally their prim descendants.

Parameters
  • visual_materials (Union[VisualMaterial, List[VisualMaterial]]) – visual materials to be applied to the prims. Currently supports PreviewSurface, OmniPBR and OmniGlass. If a list is provided then its size has to be equal the view’s size or indices size. If one material is provided it will be applied to all prims in the view.

  • weaker_than_descendants (Optional[Union[bool, List[bool]]], optional) – True if the material shouldn’t override the descendants materials, otherwise False. Defaults to False. If a list of visual materials is provided then a list has to be provided with the same size for this arg as well.

  • indices (Optional[Union[np.ndarray, list, torch.Tensor, wp.array]], optional) – indices to specify which prims to manipulate. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

Raises
  • Exception – length of visual materials != length of prims indexed

  • Exception – length of visual materials != length of weaker descendants bools arg

Example:

>>> from omni.isaac.core.materials import OmniGlass
>>>
>>> # create a dark-red glass visual material
>>> material = OmniGlass(
...     prim_path="/World/material/glass",  # path to the material prim to create
...     ior=1.25,
...     depth=0.001,
...     thin_walled=False,
...     color=np.array([0.5, 0.0, 0.0])
... )
>>> prims.apply_visual_materials(material)
property body_names: List[str]

List of prim names for each rigid body (link) of the articulations

Returns

ordered names of bodies that corresponds to links for the articulations in the view

Return type

List[str]

Example:

>>> prims.body_names
['panda_link0', 'panda_link1', 'panda_link2', 'panda_link3', 'panda_link4', 'panda_link5',
 'panda_link6', 'panda_link7', 'panda_link8', 'panda_hand', 'panda_leftfinger', 'panda_rightfinger']
property count: int
Returns

Number of prims encapsulated in this view.

Return type

int

Example:

>>> prims.count
5
property dof_names: List[str]

List of prim names for each DOF of the articulations

Returns

ordered names of joints that corresponds to degrees of freedom for the articulations in the view

Return type

List[str]

Example:

>>> prims.dof_names
['panda_joint1', 'panda_joint2', 'panda_joint3', 'panda_joint4', 'panda_joint5',
 'panda_joint6', 'panda_joint7', 'panda_finger_joint1', 'panda_finger_joint2']
get_angular_velocities(indices: Optional[Union[numpy.ndarray, list, torch.Tensor, warp.types.array]] = None, clone: bool = True) Union[numpy.ndarray, torch.Tensor, warp.types.indexedarray]

Get the angular velocities of prims in the view.

Parameters
  • indices (Optional[Union[np.ndarray, list, torch.Tensor, wp.array]], optional) – indices to specify which prims to query. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view)

  • clone (bool, optional) – True to return a clone of the internal buffer. Otherwise False. Defaults to True.

Returns

angular velocities of the prims in the view. shape is (M, 3).

Return type

Union[np.ndarray, torch.Tensor, wp.indexedarray]

Example:

>>> # get all articulation angular velocities. Returned shape is (5, 3) for the example: 5 envs, angular (3)
>>> prims.get_angular_velocities()
[[0. 0. 0.]
 [0. 0. 0.]
 [0. 0. 0.]
 [0. 0. 0.]
 [0. 0. 0.]]
>>>
>>> # get only the articulation angular velocities for the first, middle and last of the 5 envs
>>> # Returned shape is (5, 3) for the example: 3 envs selected, angular (3)
>>> prims.get_angular_velocities(indices=np.array([0, 2, 4]))
[[0. 0. 0.]
 [0. 0. 0.]
 [0. 0. 0.]]
get_applied_actions(clone: bool = True) omni.isaac.core.utils.types.ArticulationActions

Get the last applied actions

Parameters

clone (bool, optional) – True to return clones of the internal buffers. Otherwise False. Defaults to True.

Returns

current applied actions (i.e: current position targets and velocity targets)

Return type

ArticulationActions

Example:

>>> # last applied action: joint_positions -> [0.0, -1.0, 0.0, -2.2, 0.0, 2.4, 0.8, 0.04, 0.04].
>>> # Returned shape is (5, 9) for the example: 5 envs, 9 DOFs
>>> actions = prims.get_applied_actions()
>>> actions
<omni.isaac.core.utils.types.ArticulationActions object at 0x7f28af31d870>
>>> actions.joint_positions
[[ 0.   -1.    0.   -2.2   0.    2.4   0.8   0.04  0.04]
 [ 0.   -1.    0.   -2.2   0.    2.4   0.8   0.04  0.04]
 [ 0.   -1.    0.   -2.2   0.    2.4   0.8   0.04  0.04]
 [ 0.   -1.    0.   -2.2   0.    2.4   0.8   0.04  0.04]
 [ 0.   -1.    0.   -2.2   0.    2.4   0.8   0.04  0.04]]
>>> actions.joint_velocities
[[0. 0. 0. 0. 0. 0. 0. 0. 0.]
 [0. 0. 0. 0. 0. 0. 0. 0. 0.]
 [0. 0. 0. 0. 0. 0. 0. 0. 0.]
 [0. 0. 0. 0. 0. 0. 0. 0. 0.]
 [0. 0. 0. 0. 0. 0. 0. 0. 0.]]
>>> actions.joint_efforts
[[0. 0. 0. 0. 0. 0. 0. 0. 0.]
 [0. 0. 0. 0. 0. 0. 0. 0. 0.]
 [0. 0. 0. 0. 0. 0. 0. 0. 0.]
 [0. 0. 0. 0. 0. 0. 0. 0. 0.]
 [0. 0. 0. 0. 0. 0. 0. 0. 0.]]
get_applied_joint_efforts(indices: Optional[Union[numpy.ndarray, List, torch.Tensor, warp.types.array]] = None, joint_indices: Optional[Union[numpy.ndarray, List, torch.Tensor, warp.types.array]] = None, clone: bool = True) Union[numpy.ndarray, torch.Tensor, warp.types.indexedarray]

Get the joint efforts of articulations in the view

This method will return the efforts set by the set_joint_efforts method

Parameters
  • indices (Optional[Union[np.ndarray, List, torch.Tensor, wp.array]], optional) – indices to specify which prims to query. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

  • joint_indices (Optional[Union[np.ndarray, List, torch.Tensor, wp.array]], optional) – joint indices to specify which joints to query. Shape (K,). Where K <= num of dofs. Defaults to None (i.e: all dofs).

  • clone (bool, optional) – True to return a clone of the internal buffer. Otherwise False. Defaults to True.

Returns

joint efforts of articulations in the view. Shape is (M, K).

Return type

Union[np.ndarray, torch.Tensor, wp.indexedarray]

Example:

>>> # get all applied joint efforts. Returned shape is (5, 9) for the example: 5 envs, 9 DOFs
>>> prims.get_applied_joint_efforts()
[[0. 0. 0. 0. 0. 0. 0. 0. 0.]
 [0. 0. 0. 0. 0. 0. 0. 0. 0.]
 [0. 0. 0. 0. 0. 0. 0. 0. 0.]
 [0. 0. 0. 0. 0. 0. 0. 0. 0.]
 [0. 0. 0. 0. 0. 0. 0. 0. 0.]]
>>>
>>> # get finger applied efforts: panda_finger_joint1 (7) and panda_finger_joint2 (8)
>>> # for the first, middle and last of the 5 envs. Returned shape is (3, 2)
>>> prims.get_applied_joint_efforts(indices=np.array([0, 2, 4]), joint_indices=np.array([7, 8]))
[[0. 0.]
 [0. 0.]
 [0. 0.]]
get_applied_visual_materials(indices: Optional[Union[numpy.ndarray, list, torch.Tensor, warp.types.array]] = None) List[omni.isaac.core.materials.visual_material.VisualMaterial]

Get the current applied visual materials

Parameters

indices (Optional[Union[np.ndarray, list, torch.Tensor, wp.array]], optional) – indices to specify which prims to query. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

Returns

a list of the current applied visual materials to the prims if its type is currently supported.

Return type

List[VisualMaterial]

Example:

>>> # get all applied visual materials. Returned size is 5 for the example: 5 envs
>>> prims.get_applied_visual_materials()
[<omni.isaac.core.materials.omni_glass.OmniGlass object at 0x7f829c165de0>,
 <omni.isaac.core.materials.omni_glass.OmniGlass object at 0x7f829c165de0>,
 <omni.isaac.core.materials.omni_glass.OmniGlass object at 0x7f829c165de0>,
 <omni.isaac.core.materials.omni_glass.OmniGlass object at 0x7f829c165de0>,
 <omni.isaac.core.materials.omni_glass.OmniGlass object at 0x7f829c165de0>]
>>>
>>> # get the applied visual materials for the first, middle and last of the 5 envs. Returned size is 3
>>> prims.get_applied_visual_materials(indices=np.array([0, 2, 4]))
[<omni.isaac.core.materials.omni_glass.OmniGlass object at 0x7f829c165de0>,
 <omni.isaac.core.materials.omni_glass.OmniGlass object at 0x7f829c165de0>,
 <omni.isaac.core.materials.omni_glass.OmniGlass object at 0x7f829c165de0>]
get_armatures(indices: Optional[Union[numpy.ndarray, List, torch.Tensor, warp.types.array]] = None, joint_indices: Optional[Union[numpy.ndarray, List, torch.Tensor, warp.types.array]] = None, clone: bool = True) Union[numpy.ndarray, torch.Tensor, warp.types.indexedarray]

Get armatures for articulation joints in the view

Search for “Joint Armature” in PhysX docs for more details.

Parameters
  • indices (Optional[Union[np.ndarray, List, torch.Tensor, wp.array]], optional) – indices to specify which prims to query. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

  • joint_indices (Optional[Union[np.ndarray, List, torch.Tensor, wp.array]], optional) – joint indices to specify which joints to query. Shape (K,). Where K <= num of dofs. Defaults to None (i.e: all dofs).

  • clone (Optional[bool]) – True to return a clone of the internal buffer. Otherwise False. Defaults to True.

Returns

joint armatures for articulations in the view. shape (M, K).

Return type

Union[np.ndarray, torch.Tensor, wp.indexedarray]

Example:

>>> # get joint armatures. Returned shape is (5, 9) for the example: 5 envs, 9 DOFs
>>> prims.get_armatures()
[[0. 0. 0. 0. 0. 0. 0. 0. 0.]
 [0. 0. 0. 0. 0. 0. 0. 0. 0.]
 [0. 0. 0. 0. 0. 0. 0. 0. 0.]
 [0. 0. 0. 0. 0. 0. 0. 0. 0.]
 [0. 0. 0. 0. 0. 0. 0. 0. 0.]]
>>>
>>> # get only the finger joint (panda_finger_joint1 (7) and panda_finger_joint2 (8)) armatures
>>> # for the first, middle and last of the 5 envs. Returned shape is (3, 2)
>>> prims.get_armatures(indices=np.array([0,2,4]), joint_indices=np.array([7,8]))
[[0. 0.]
 [0. 0.]
 [0. 0.]]
get_articulation_body_count() int

Get the number of rigid bodies (links) of the articulations

Returns

maximum number of rigid bodies (links) in the articulation

Return type

int

Example:

>>> prims.get_articulation_body_count()
12
get_body_coms(indices: Optional[Union[numpy.ndarray, List, torch.Tensor, warp.types.array]] = None, body_indices: Optional[Union[numpy.ndarray, List, torch.Tensor, warp.types.array]] = None, clone: bool = True) Union[numpy.ndarray, torch.Tensor, warp.types.indexedarray]

Get rigid body center of mass (COM) of articulations in the view.

Parameters
  • indices (Optional[Union[np.ndarray, List, torch.Tensor, wp.array]], optional) – indices to specify which prims to query. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

  • body_indices (Optional[Union[np.ndarray, List, torch.Tensor, wp.array]], optional) – body indices to specify which bodies to query. Shape (K,). Where K <= num of bodies. Defaults to None (i.e: all bodies).

  • clone (bool, optional) – True to return a clone of the internal buffer. Otherwise False. Defaults to True.

Returns

rigid body center of mass positions and orientations of articulations in the view. Position shape is (M, K, 3), orientation shape is (M, k, 4).

Return type

Union[np.ndarray, torch.Tensor, wp.indexedarray]

Example:

>>> # get all body center of mass. Returned shape is (5, 12, 3) for positions and (5, 12, 4) for orientations
>>> # for the example: 5 envs, 12 rigid bodies
>>> positions, orientations = prims.get_body_coms()
>>> positions
[[[0. 0. 0.]
  [0. 0. 0.]
  ...
  [0. 0. 0.]
  [0. 0. 0.]]]
>>> orientations
[[[1. 0. 0. 0.]
  [1. 0. 0. 0.]
  ...
  [1. 0. 0. 0.]
  [1. 0. 0. 0.]]]
>>>
>>> # get finger body center of mass: panda_leftfinger (10) and panda_rightfinger (11) for the first,
>>> # middle and last of the 5 envs. Returned shape is (3, 2, 3) for positions and (3, 2, 4) for orientations
>>> positions, orientations = prims.get_body_coms(indices=np.array([0, 2, 4]), body_indices=np.array([10, 11]))
>>> positions
[[[0. 0. 0.]
  [0. 0. 0.]]
 [[0. 0. 0.]
  [0. 0. 0.]]
 [[0. 0. 0.]
  [0. 0. 0.]]]
>>> orientations
[[[1. 0. 0. 0.]
  [1. 0. 0. 0.]]
 [[1. 0. 0. 0.]
  [1. 0. 0. 0.]]
 [[1. 0. 0. 0.]
  [1. 0. 0. 0.]]]
get_body_index(body_name: str) int

Get a ridig body (link) index in the articulation view given its name

Parameters

body_name (str) – name of the ridig body to query

Returns

index of the rigid body in the articulation buffers

Return type

int

Example:

>>> # get the index of the left finger: panda_leftfinger
>>> prims.get_body_index("panda_leftfinger")
10
get_body_inertias(indices: Optional[Union[numpy.ndarray, List, torch.Tensor, warp.types.array]] = None, body_indices: Optional[Union[numpy.ndarray, List, torch.Tensor, warp.types.array]] = None, clone: bool = True) Union[numpy.ndarray, torch.Tensor, warp.types.indexedarray]

Get rigid body inertias of articulations in the view

Parameters
  • indices (Optional[Union[np.ndarray, List, torch.Tensor, wp.array]], optional) – indices to specify which prims to query. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

  • body_indices (Optional[Union[np.ndarray, List, torch.Tensor, wp.array]], optional) – body indices to specify which bodies to query. Shape (K,). Where K <= num of bodies. Defaults to None (i.e: all bodies).

  • clone (bool, optional) – True to return a clone of the internal buffer. Otherwise False. Defaults to True.

Returns

rigid body inertias of articulations in the view. Shape is (M, K, 9).

Return type

Union[np.ndarray, torch.Tensor, wp.indexedarray]

Example:

>>> # get all body inertias. Returned shape is (5, 12, 9) for the example: 5 envs, 12 rigid bodies
>>> prims.get_body_inertias()
[[[1.2988697e-06  0.0  0.0  0.0  1.6535528e-06  0.0  0.0  0.0  2.0331163e-06]
  [1.8686389e-06  0.0  0.0  0.0  1.4378986e-06  0.0  0.0  0.0  9.0681192e-07]
  ...
  [4.2041304e-10  0.0  0.0  0.0  3.9026365e-10  0.0  0.0  0.0  1.3347495e-10]
  [4.2041304e-10  0.0  0.0  0.0  3.9026365e-10  0.0  0.0  0.0  1.3347495e-10]]]
>>>
>>> # get finger body inertias: panda_leftfinger (10) and panda_rightfinger (11)
>>> # for the first, middle and last of the 5 envs. Returned shape is (3, 2, 9)
>>> prims.get_body_inertias(indices=np.array([0, 2, 4]), body_indices=np.array([10, 11]))
[[[4.2041304e-10  0.0  0.0  0.0  3.9026365e-10  0.0  0.0  0.0  1.3347495e-10]
  [4.2041304e-10  0.0  0.0  0.0  3.9026365e-10  0.0  0.0  0.0  1.3347495e-10]]
 ...
 [[4.2041304e-10  0.0  0.0  0.0  3.9026365e-10  0.0  0.0  0.0  1.3347495e-10]
  [4.2041304e-10  0.0  0.0  0.0  3.9026365e-10  0.0  0.0  0.0  1.3347495e-10]]]
get_body_inv_inertias(indices: Optional[Union[numpy.ndarray, List, torch.Tensor, warp.types.array]] = None, body_indices: Optional[Union[numpy.ndarray, List, torch.Tensor, warp.types.array]] = None, clone: bool = True) Union[numpy.ndarray, torch.Tensor, warp.types.indexedarray]

Get rigid body inverse inertias of articulations in the view

Parameters
  • indices (Optional[Union[np.ndarray, List, torch.Tensor, wp.array]], optional) – indices to specify which prims to query. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

  • body_indices (Optional[Union[np.ndarray, List, torch.Tensor, wp.array]], optional) – body indices to specify which bodies to query. Shape (K,). Where K <= num of bodies. Defaults to None (i.e: all bodies).

  • clone (bool, optional) – True to return a clone of the internal buffer. Otherwise False. Defaults to True.

Returns

rigid body inverse inertias of articulations in the view. Shape is (M, K, 9).

Return type

Union[np.ndarray, torch.Tensor, wp.indexedarray]

Example:

>>> # get all body inverse inertias. Returned shape is (5, 12, 9) for the example: 5 envs, 12 rigid bodies
>>> prims.get_body_inv_inertias()
[[[7.6990012e+05  0.0  0.0  0.0  6.0475844e+05  0.0  0.0  0.0  4.9185578e+05]
  [5.3514888e+05  0.0  0.0  0.0  6.9545931e+05  0.0  0.0  0.0  1.1027645e+06]
  ...
  [2.3786132e+09  0.0  0.0  0.0  2.5623703e+09  0.0  0.0  0.0  7.4920422e+09]
  [2.3786132e+09  0.0  0.0  0.0  2.5623703e+09  0.0  0.0  0.0  7.4920422e+09]]]
>>>
>>> # get finger body inverse inertias: panda_leftfinger (10) and panda_rightfinger (11)
>>> # for the first, middle and last of the 5 envs. Returned shape is (3, 2, 9)
>>> prims.get_body_inv_inertias(indices=np.array([0, 2, 4]), body_indices=np.array([10, 11]))
[[[2.3786132e+09  0.0  0.0  0.0  2.5623703e+09  0.0  0.0  0.0  7.4920422e+09]
  [2.3786132e+09  0.0  0.0  0.0  2.5623703e+09  0.0  0.0  0.0  7.4920422e+09]]
 ...
 [[2.3786132e+09  0.0  0.0  0.0  2.5623703e+09  0.0  0.0  0.0  7.4920422e+09]
  [2.3786132e+09  0.0  0.0  0.0  2.5623703e+09  0.0  0.0  0.0  7.4920422e+09]]]
get_body_inv_masses(indices: Optional[Union[numpy.ndarray, List, torch.Tensor, warp.types.array]] = None, body_indices: Optional[Union[numpy.ndarray, List, torch.Tensor, warp.types.array]] = None, clone: bool = True) Union[numpy.ndarray, torch.Tensor, warp.types.indexedarray]

Get rigid body inverse masses of articulations in the view

Parameters
  • indices (Optional[Union[np.ndarray, List, torch.Tensor, wp.array]], optional) – indices to specify which prims to query. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

  • body_indices (Optional[Union[np.ndarray, List, torch.Tensor, wp.array]], optional) – body indices to specify which bodies to query. Shape (K,). Where K <= num of bodies. Defaults to None (i.e: all bodies).

  • clone (bool, optional) – True to return a clone of the internal buffer. Otherwise False. Defaults to True.

Returns

rigid body inverse masses of articulations in the view. Shape is (M, K).

Return type

Union[np.ndarray, torch.Tensor, wp.indexedarray]

Example:

>>> # get all body inverse masses. Returned shape is (5, 12) for the example: 5 envs, 12 rigid bodies
>>> prims.get_body_inv_masses()
[[ 0.35534042  0.42372888  0.42025304  0.37737525  0.3710848  0.33542618  0.8860687
   2.4673615  10. 1.7910539  71.14793  71.14793]
 [ 0.35534042  0.42372888  0.42025304  0.37737525  0.3710848  0.33542618  0.8860687
   2.4673615  10. 1.7910539  71.14793  71.14793]
 [ 0.35534042  0.42372888  0.42025304  0.37737525  0.3710848  0.33542618  0.8860687
   2.4673615  10. 1.7910539  71.14793  71.14793]
 [ 0.35534042  0.42372888  0.42025304  0.37737525  0.3710848  0.33542618  0.8860687
   2.4673615  10. 1.7910539  71.14793  71.14793]
 [ 0.35534042  0.42372888  0.42025304  0.37737525  0.3710848  0.33542618  0.8860687
   2.4673615  10. 1.7910539  71.14793  71.14793]]
>>>
>>> # get finger body inverse masses: panda_leftfinger (10) and panda_rightfinger (11)
>>> # for the first, middle and last of the 5 envs. Returned shape is (3, 2)
>>> prims.get_body_inv_masses(indices=np.array([0, 2, 4]), body_indices=np.array([10, 11]))
[[71.14793 71.14793]
 [71.14793 71.14793]
 [71.14793 71.14793]]
get_body_masses(indices: Optional[Union[numpy.ndarray, List, torch.Tensor, warp.types.array]] = None, body_indices: Optional[Union[numpy.ndarray, List, torch.Tensor, warp.types.array]] = None, clone: bool = True) Union[numpy.ndarray, torch.Tensor, warp.types.indexedarray]

Get rigid body masses of articulations in the view

Parameters
  • indices (Optional[Union[np.ndarray, List, torch.Tensor, wp.array]], optional) – indices to specify which prims to query. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

  • body_indices (Optional[Union[np.ndarray, List, torch.Tensor, wp.array]], optional) – body indices to specify which bodies to query. Shape (K,). Where K <= num of bodies. Defaults to None (i.e: all bodies).

  • clone (bool, optional) – True to return a clone of the internal buffer. Otherwise False. Defaults to True.

Returns

rigid body masses of articulations in the view. Shape is (M, K).

Return type

Union[np.ndarray, torch.Tensor, wp.indexedarray]

Example:

>>> # get all body masses. Returned shape is (5, 12) for the example: 5 envs, 12 rigid bodies
>>> prims.get_body_masses()
[[2.8142028  2.3599997  2.3795187  2.6498823  2.6948018  2.981282
  1.1285807  0.40529126 0.1  0.5583305  0.01405522 0.01405522]
 [2.8142028  2.3599997  2.3795187  2.6498823  2.6948018  2.981282
  1.1285807  0.40529126 0.1  0.5583305  0.01405522 0.01405522]
 [2.8142028  2.3599997  2.3795187  2.6498823  2.6948018  2.981282
  1.1285807  0.40529126 0.1  0.5583305  0.01405522 0.01405522]
 [2.8142028  2.3599997  2.3795187  2.6498823  2.6948018  2.981282
  1.1285807  0.40529126 0.1  0.5583305  0.01405522 0.01405522]
 [2.8142028  2.3599997  2.3795187  2.6498823  2.6948018  2.981282
  1.1285807  0.40529126 0.1  0.5583305  0.01405522 0.01405522]]
>>>
>>> # get finger body masses: panda_leftfinger (10) and panda_rightfinger (11)
>>> # for the first, middle and last of the 5 envs. Returned shape is (3, 2)
>>> prims.get_body_masses(indices=np.array([0, 2, 4]), body_indices=np.array([10, 11]))
[[0.01405522 0.01405522]
 [0.01405522 0.01405522]
 [0.01405522 0.01405522]]
get_coriolis_and_centrifugal_forces(indices: Optional[Union[numpy.ndarray, List, torch.Tensor, warp.types.array]] = None, joint_indices: Optional[Union[numpy.ndarray, List, torch.Tensor, warp.types.array]] = None, clone: bool = True) Union[numpy.ndarray, torch.Tensor, warp.types.indexedarray]

Get the Coriolis and centrifugal forces (joint DOF forces required to counteract Coriolis and centrifugal forces for the given articulation state) of articulations in the view

Search for Coriolis and Centrifugal Forces in PhysX docs for more details

Parameters
  • indices (Optional[Union[np.ndarray, List, torch.Tensor, wp.array]], optional) – indices to specify which prims to query. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

  • joint_indices (Optional[Union[np.ndarray, List, torch.Tensor, wp.array]], optional) – joint indices to specify which joints to query. Shape (K,). Where K <= num of dofs. Defaults to None (i.e: all dofs).

  • clone (bool, optional) – True to return a clone of the internal buffer. Otherwise False. Defaults to True.

Returns

Coriolis and centrifugal forces of articulations in the view. Shape is (M, K).

Return type

Union[np.ndarray, torch.Tensor, wp.indexedarray]

Example:

>>> # get all coriolis and centrifugal forces. Returned shape is (5, 9) for the example: 5 envs, 9 DOFs
>>> prims.get_coriolis_and_centrifugal_forces()
[[ 1.6842524e-06 -1.8269569e-04  5.2162073e-07 -9.7677548e-05  3.0365106e-07
   6.7375149e-06  6.1105780e-08 -4.6237556e-06 -4.1627968e-06]
 [ 1.6842524e-06 -1.8269569e-04  5.2162073e-07 -9.7677548e-05  3.0365106e-07
   6.7375149e-06  6.1105780e-08 -4.6237556e-06 -4.1627968e-06]
 [ 1.6842561e-06 -1.8269687e-04  5.2162375e-07 -9.7677454e-05  3.0365084e-07
   6.7375931e-06  6.1106007e-08 -4.6237533e-06 -4.1627954e-06]
 [ 1.6842561e-06 -1.8269687e-04  5.2162375e-07 -9.7677454e-05  3.0365084e-07
   6.7375931e-06  6.1106007e-08 -4.6237533e-06 -4.1627954e-06]
 [ 1.6842524e-06 -1.8269569e-04  5.2162073e-07 -9.7677548e-05  3.0365106e-07
   6.7375149e-06  6.1105780e-08 -4.6237556e-06 -4.1627968e-06]]
>>>
>>> # get finger joint coriolis and centrifugal forces: panda_finger_joint1 (7) and panda_finger_joint2 (8)
>>> # for the first, middle and last of the 5 envs. Returned shape is (3, 2)
>>> prims.get_coriolis_and_centrifugal_forces(indices=np.array([0, 2, 4]), joint_indices=np.array([7, 8]))
[[-4.6237556e-06 -4.1627968e-06]
 [-4.6237533e-06 -4.1627954e-06]
 [-4.6237556e-06 -4.1627968e-06]]
get_default_state() omni.isaac.core.utils.types.XFormPrimViewState

Get the default states (positions and orientations) defined with the set_default_state method

Returns

returns the default state of the prims that is used after each reset.

Return type

XFormPrimViewState

Example:

>>> state = prims.get_default_state()
>>> state
<omni.isaac.core.utils.types.XFormPrimViewState object at 0x7f82f73e3070>
>>> state.positions
[[ 1.5  -0.75  0.  ]
 [ 1.5   0.75  0.  ]
 [ 0.   -0.75  0.  ]
 [ 0.    0.75  0.  ]
 [-1.5  -0.75  0.  ]]
>>> state.orientations
[[1. 0. 0. 0.]
 [1. 0. 0. 0.]
 [1. 0. 0. 0.]
 [1. 0. 0. 0.]
 [1. 0. 0. 0.]]
get_dof_index(dof_name: str) int

Get a DOF index in the joint buffers given its name

Parameters

dof_name (str) – name of the joint that corresponds to the degree of freedom to query

Returns

index of the degree of freedom in the joint buffers

Return type

int

Example:

>>> # get the index of the left finger joint: panda_finger_joint1
>>> prims.get_dof_index("panda_finger_joint1")
7
get_dof_limits() Union[numpy.ndarray, torch.Tensor]

Get the articulations DOFs limits (lower and upper)

Returns

degrees of freedom position limits. Shape is (N, num_dof, 2). For the last dimension, index 0 corresponds to lower limits and index 1 corresponds to upper limits

Return type

Union[np.ndarray, torch.Tensor, wp.array]

Example:

>>> # get DOF limits. Returned shape is (5, 9, 2) for the example: 5 envs, 9 DOFs
>>> prims.get_dof_limits()
[[[-2.8973  2.8973]
 [-1.7628  1.7628]
 [-2.8973  2.8973]
 [-3.0718 -0.0698]
 [-2.8973  2.8973]
 [-0.0175  3.7525]
 [-2.8973  2.8973]
 [ 0.      0.04  ]
 [ 0.      0.04  ]]
...
[[-2.8973  2.8973]
 [-1.7628  1.7628]
 [-2.8973  2.8973]
 [-3.0718 -0.0698]
 [-2.8973  2.8973]
 [-0.0175  3.7525]
 [-2.8973  2.8973]
 [ 0.      0.04  ]
 [ 0.      0.04  ]]]
get_dof_types(dof_names: Optional[List[str]] = None) List[str]

Get the DOF types given the DOF names

Parameters

dof_names (List[str], optional) – names of the joints that corresponds to the degrees of freedom to query. Defaults to None.

Returns

types of the joints that corresponds to the degrees of freedom. Types can be invalid, translation or rotation.

Return type

List[str]

Example:

>>> # get all DOF types
>>> prims.get_dof_types()
[<DofType.Rotation: 0>, <DofType.Rotation: 0>, <DofType.Rotation: 0>,
 <DofType.Rotation: 0>, <DofType.Rotation: 0>, <DofType.Rotation: 0>,
 <DofType.Rotation: 0>, <DofType.Translation: 1>, <DofType.Translation: 1>]
>>>
>>> # get only the finger DOF types: panda_finger_joint1 and panda_finger_joint2
>>> prims.get_dof_types(dof_names=["panda_finger_joint1", "panda_finger_joint2"])
[<DofType.Translation: 1>, <DofType.Translation: 1>]
get_effort_modes(indices: Optional[Union[numpy.ndarray, List, torch.Tensor, warp.types.array]] = None, joint_indices: Optional[Union[numpy.ndarray, List, torch.Tensor, warp.types.array]] = None) List[str]

Get effort modes for articulations in the view

Parameters
  • indices (Optional[Union[np.ndarray, List, torch.Tensor, wp.array]], optional) – indices to specify which prims to query. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

  • joint_indices (Optional[Union[np.ndarray, List, torch.Tensor, wp.array]], optional) – joint indices to specify which joints to query. Shape (K,). Where K <= num of dofs. Defaults to None (i.e: all dofs).

Returns

Returns a List of size (M, K) indicating the effort modes: acceleration or force

Return type

List

Example:

>>> # get the effort mode for all joints
>>> prims.get_effort_modes()
[['acceleration', 'acceleration', 'acceleration', 'acceleration', 'acceleration', 'acceleration', 'acceleration', 'acceleration', 'acceleration'],
 ['acceleration', 'acceleration', 'acceleration', 'acceleration', 'acceleration', 'acceleration', 'acceleration', 'acceleration', 'acceleration'],
 ['acceleration', 'acceleration', 'acceleration', 'acceleration', 'acceleration', 'acceleration', 'acceleration', 'acceleration', 'acceleration'],
 ['acceleration', 'acceleration', 'acceleration', 'acceleration', 'acceleration', 'acceleration', 'acceleration', 'acceleration', 'acceleration'],
 ['acceleration', 'acceleration', 'acceleration', 'acceleration', 'acceleration', 'acceleration', 'acceleration', 'acceleration', 'acceleration']]
>>>
>>> # get only the finger joints effort modes for the first, middle and last of the 5 envs
>>> prims.get_effort_modes(indices=np.array([0, 2, 4]), joint_indices=np.array([7, 8]))
[['acceleration', 'acceleration'], ['acceleration', 'acceleration'], ['acceleration', 'acceleration']]
get_enabled_self_collisions(indices: Optional[Union[numpy.ndarray, List, torch.Tensor, warp.types.array]] = None) Union[numpy.ndarray, torch.Tensor, warp.types.indexedarray]

Get the enable self collisions flag (physxArticulation:enabledSelfCollisions) for all articulations

Parameters

indices (Optional[Union[np.ndarray, List, torch.Tensor, wp.array]], optional) – indices to specify which prims to query. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

Returns

self collisions flags (boolean interpreted as int). shape (M,)

Return type

Union[np.ndarray, torch.Tensor, wp.indexedarray]

Example:

>>> # get all self collisions flags. Returned shape is (5,) for the example: 5 envs
>>> prims.get_enabled_self_collisions()
[0 0 0 0 0]
>>>
>>> # get the self collisions flags for the first, middle and last of the 5 envs. Returned shape is (3,)
>>> prims.get_enabled_self_collisions(indices=np.array([0, 2, 4]))
[0 0 0]
get_fixed_tendon_dampings(indices: Optional[Union[numpy.ndarray, List, torch.Tensor, warp.types.array]] = None, clone: bool = True) Union[numpy.ndarray, torch.Tensor, warp.types.indexedarray]

Get the dampings of fixed tendons for articulations in the view

Search for Fixed Tendon in PhysX docs for more details

Parameters
  • indices (Optional[Union[np.ndarray, List, torch.Tensor, wp.array]], optional) – indices to specify which prims to query. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

  • clone (bool, optional) – True to return a clone of the internal buffer. Otherwise False. Defaults to True.

Returns

fixed tendon dampings of articulations in the view. Shape is (M, K).

Return type

Union[np.ndarray, torch.Tensor, wp.indexedarray]

Example:

>>> # get the fixed tendon dampings
>>> # for the ShadowHand articulation that has 4 fixed tendons (prims.num_fixed_tendons)
>>> prims.get_fixed_tendon_dampings()
[[0. 0. 0. 0.]
 [0. 0. 0. 0.]
 [0. 0. 0. 0.]
 [0. 0. 0. 0.]
 [0. 0. 0. 0.]]
get_fixed_tendon_limit_stiffnesses(indices: Optional[Union[numpy.ndarray, List, torch.Tensor, warp.types.array]] = None, clone: bool = True) Union[numpy.ndarray, torch.Tensor, warp.types.indexedarray]

Get the limit stiffness of fixed tendons for articulations in the view

Search for Fixed Tendon in PhysX docs for more details

Parameters
  • indices (Optional[Union[np.ndarray, List, torch.Tensor, wp.array]], optional) – indices to specify which prims to query. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

  • clone (bool, optional) – True to return a clone of the internal buffer. Otherwise False. Defaults to True.

Returns

fixed tendon stiffnesses of articulations in the view. Shape is (M, K).

Return type

Union[np.ndarray, torch.Tensor, wp.indexedarray]

Example:

>>> # get the fixed tendon limit stiffnesses
>>> # for the ShadowHand articulation that has 4 fixed tendons (prims.num_fixed_tendons)
>>> prims.get_fixed_tendon_limit_stiffnesses()
[[0. 0. 0. 0.]
 [0. 0. 0. 0.]
 [0. 0. 0. 0.]
 [0. 0. 0. 0.]
 [0. 0. 0. 0.]]
get_fixed_tendon_limits(indices: Optional[Union[numpy.ndarray, List, torch.Tensor, warp.types.array]] = None, clone: bool = True) Union[numpy.ndarray, torch.Tensor, warp.types.indexedarray]

Get the limits of fixed tendons for articulations in the view

Search for Fixed Tendon in PhysX docs for more details

Parameters
  • indices (Optional[Union[np.ndarray, List, torch.Tensor, wp.array]], optional) – indices to specify which prims to query. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

  • clone (bool, optional) – True to return a clone of the internal buffer. Otherwise False. Defaults to True.

Returns

fixed tendon stiffnesses of articulations in the view. Shape is (M, K, 2).

Return type

Union[np.ndarray, torch.Tensor, wp.indexedarray]

Example:

>>> # get the fixed tendon limits
>>> # for the ShadowHand articulation that has 4 fixed tendons (prims.num_fixed_tendons)
>>> prims.get_fixed_tendon_limits()
[[[-0.001  0.001] [-0.001  0.001] [-0.001  0.001] [-0.001  0.001]]
 [[-0.001  0.001] [-0.001  0.001] [-0.001  0.001] [-0.001  0.001]]
 [[-0.001  0.001] [-0.001  0.001] [-0.001  0.001] [-0.001  0.001]]
 [[-0.001  0.001] [-0.001  0.001] [-0.001  0.001] [-0.001  0.001]]
 [[-0.001  0.001] [-0.001  0.001] [-0.001  0.001] [-0.001  0.001]]]
get_fixed_tendon_offsets(indices: Optional[Union[numpy.ndarray, List, torch.Tensor, warp.types.array]] = None, clone: bool = True) Union[numpy.ndarray, torch.Tensor, warp.types.indexedarray]

Get the offsets of fixed tendons for articulations in the view

Search for Fixed Tendon in PhysX docs for more details

Parameters
  • indices (Optional[Union[np.ndarray, List, torch.Tensor, wp.array]], optional) – indices to specify which prims to query. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

  • clone (bool, optional) – True to return a clone of the internal buffer. Otherwise False. Defaults to True.

Returns

fixed tendon stiffnesses of articulations in the view. Shape is (M, K).

Return type

Union[np.ndarray, torch.Tensor, wp.indexedarray]

Example:

>>> # get the fixed tendon offsets
>>> # for the ShadowHand articulation that has 4 fixed tendons (prims.num_fixed_tendons)
>>> prims.get_fixed_tendon_offsets()
[[0. 0. 0. 0.]
 [0. 0. 0. 0.]
 [0. 0. 0. 0.]
 [0. 0. 0. 0.]
 [0. 0. 0. 0.]]
get_fixed_tendon_rest_lengths(indices: Optional[Union[numpy.ndarray, List, torch.Tensor, warp.types.array]] = None, clone: bool = True) Union[numpy.ndarray, torch.Tensor, warp.types.indexedarray]

Get the rest length of fixed tendons for articulations in the view

Search for Fixed Tendon in PhysX docs for more details

Parameters
  • indices (Optional[Union[np.ndarray, List, torch.Tensor, wp.array]], optional) – indices to specify which prims to query. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

  • clone (bool, optional) – True to return a clone of the internal buffer. Otherwise False. Defaults to True.

Returns

fixed tendon stiffnesses of articulations in the view. Shape is (M, K).

Return type

Union[np.ndarray, torch.Tensor, wp.indexedarray]

Example:

>>> # get the fixed tendon rest lengths
>>> # for the ShadowHand articulation that has 4 fixed tendons (prims.num_fixed_tendons)
>>> prims.get_fixed_tendon_rest_lengths()
[[0. 0. 0. 0.]
 [0. 0. 0. 0.]
 [0. 0. 0. 0.]
 [0. 0. 0. 0.]
 [0. 0. 0. 0.]]
get_fixed_tendon_stiffnesses(indices: Optional[Union[numpy.ndarray, List, torch.Tensor, warp.types.array]] = None, clone: bool = True) Union[numpy.ndarray, torch.Tensor, warp.types.indexedarray]

Get the stiffness of fixed tendons for articulations in the view

Search for Fixed Tendon in PhysX docs for more details

Parameters
  • indices (Optional[Union[np.ndarray, List, torch.Tensor, wp.array]], optional) – indices to specify which prims to query. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

  • clone (bool, optional) – True to return a clone of the internal buffer. Otherwise False. Defaults to True.

Returns

fixed tendon stiffnesses of articulations in the view. Shape is (M, K).

Return type

Union[np.ndarray, torch.Tensor, wp.indexedarray]

Example:

>>> # get the fixed tendon stiffnesses
>>> # for the ShadowHand articulation that has 4 fixed tendons (prims.num_fixed_tendons)
>>> prims.get_fixed_tendon_stiffnesses()
[[0. 0. 0. 0.]
 [0. 0. 0. 0.]
 [0. 0. 0. 0.]
 [0. 0. 0. 0.]
 [0. 0. 0. 0.]]
get_friction_coefficients(indices: Optional[Union[numpy.ndarray, List, torch.Tensor, warp.types.array]] = None, joint_indices: Optional[Union[numpy.ndarray, List, torch.Tensor, warp.types.array]] = None, clone: bool = True) Union[numpy.ndarray, torch.Tensor, warp.types.array]

Get the friction coefficients for the articulation joints in the view

Search for “Joint Friction Coefficient” in PhysX docs for more details.

Parameters
  • indices (Optional[Union[np.ndarray, List, torch.Tensor, wp.array]], optional) – indices to specify which prims to query. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

  • joint_indices (Optional[Union[np.ndarray, List, torch.Tensor, wp.array]], optional) – joint indices to specify which joints to query. Shape (K,). Where K <= num of dofs. Defaults to None (i.e: all dofs).

  • clone (Optional[bool]) – True to return a clone of the internal buffer. Otherwise False. Defaults to True.

Returns

joint friction coefficients for articulations in the view. shape (M, K).

Return type

Union[np.ndarray, torch.Tensor, wp.indexedarray]

Example:

>>> # get joint friction coefficients. Returned shape is (5, 9) for the example: 5 envs, 9 DOFs
>>> prims.get_friction_coefficients()
[[0. 0. 0. 0. 0. 0. 0. 0. 0.]
 [0. 0. 0. 0. 0. 0. 0. 0. 0.]
 [0. 0. 0. 0. 0. 0. 0. 0. 0.]
 [0. 0. 0. 0. 0. 0. 0. 0. 0.]
 [0. 0. 0. 0. 0. 0. 0. 0. 0.]]
>>>
>>> # get only the finger joint (panda_finger_joint1 (7) and panda_finger_joint2 (8)) friction coefficients
>>> # for the first, middle and last of the 5 envs. Returned shape is (3, 2)
>>> prims.get_friction_coefficients(indices=np.array([0,2,4]), joint_indices=np.array([7,8]))
[[0. 0.]
 [0. 0.]
 [0. 0.]]
get_gains(indices: Optional[Union[numpy.ndarray, List, torch.Tensor, warp.types.array]] = None, joint_indices: Optional[Union[numpy.ndarray, List, torch.Tensor, warp.types.array]] = None, clone: bool = True) Tuple[typing.Union[numpy.ndarray, torch.Tensor], typing.Union[numpy.ndarray, torch.Tensor], typing.Union[warp.types.indexedarray, <Function index(a: vec2h, i: int32)>]]

Get the implicit Proportional-Derivative (PD) controller’s Kps (stiffnesses) and Kds (dampings) of articulations in the view

Parameters
  • indices (Optional[Union[np.ndarray, List, torch.Tensor, wp.array]], optional) – indices to specify which prims to query. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

  • joint_indices (Optional[Union[np.ndarray, List, torch.Tensor, wp.array]], optional) – joint indices to specify which joints to query. Shape (K,). Where K <= num of dofs. Defaults to None (i.e: all dofs).

  • clone (bool, optional) – True to return clones of the internal buffers. Otherwise False. Defaults to True.

Returns

stiffness and damping of articulations in the view respectively. shapes are (M, K).

Return type

Tuple[Union[np.ndarray, torch.Tensor], Union[np.ndarray, torch.Tensor], Union[wp.indexedarray, wp.index]]

Example:

>>> # get all joint stiffness and damping. Returned shape is (5, 9) for the example: 5 envs, 9 DOFs
>>> stiffnesses, dampings = prims.get_gains()
>>> stiffnesses
[[60000. 60000. 60000. 60000. 25000. 15000.  5000.  6000.  6000.]
 [60000. 60000. 60000. 60000. 25000. 15000.  5000.  6000.  6000.]
 [60000. 60000. 60000. 60000. 25000. 15000.  5000.  6000.  6000.]
 [60000. 60000. 60000. 60000. 25000. 15000.  5000.  6000.  6000.]
 [60000. 60000. 60000. 60000. 25000. 15000.  5000.  6000.  6000.]]
>>> dampings
[[3000. 3000. 3000. 3000. 3000. 3000. 3000. 1000. 1000.]
 [3000. 3000. 3000. 3000. 3000. 3000. 3000. 1000. 1000.]
 [3000. 3000. 3000. 3000. 3000. 3000. 3000. 1000. 1000.]
 [3000. 3000. 3000. 3000. 3000. 3000. 3000. 1000. 1000.]
 [3000. 3000. 3000. 3000. 3000. 3000. 3000. 1000. 1000.]]
>>>
>>> # get finger joints stiffness and damping: panda_finger_joint1 (7) and panda_finger_joint2 (8)
>>> # for the first, middle and last of the 5 envs. Returned shape is (3, 2)
>>> stiffnesses, dampings = prims.get_gains(indices=np.array([0, 2, 4]), joint_indices=np.array([7, 8]))
>>> stiffnesses
[[6000. 6000.]
 [6000. 6000.]
 [6000. 6000.]]
>>> dampings
[[1000. 1000.]
 [1000. 1000.]
 [1000. 1000.]]
get_generalized_gravity_forces(indices: Optional[Union[numpy.ndarray, List, torch.Tensor, warp.types.array]] = None, joint_indices: Optional[Union[numpy.ndarray, List, torch.Tensor, warp.types.array]] = None, clone: bool = True) Union[numpy.ndarray, torch.Tensor, warp.types.indexedarray]

Get the generalized gravity forces (joint DOF forces required to counteract gravitational forces for the given articulation pose) of articulations in the view

Search for Generalized Gravity Force in PhysX docs for more details

Parameters
  • indices (Optional[Union[np.ndarray, List, torch.Tensor, wp.array]], optional) – indices to specify which prims to query. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

  • joint_indices (Optional[Union[np.ndarray, List, torch.Tensor, wp.array]], optional) – joint indices to specify which joints to query. Shape (K,). Where K <= num of dofs. Defaults to None (i.e: all dofs).

  • clone (bool, optional) – True to return a clone of the internal buffer. Otherwise False. Defaults to True.

Returns

generalized gravity forces of articulations in the view. Shape is (M, K).

Return type

Union[np.ndarray, torch.Tensor, wp.indexedarray]

Example:

>>>

>>> # get all generalized gravity forces. Returned shape is (5, 9) for the example: 5 envs, 9 DOFs
>>> prims.get_generalized_gravity_forces()
[[ 1.32438602e-08 -6.90832138e+00 -1.08629465e-05  1.91585541e+01  5.13810664e-06
   1.18674076e+00  8.01788883e-06  5.18786255e-03 -5.18784765e-03]
 [ 1.32438602e-08 -6.90832138e+00 -1.08629465e-05  1.91585541e+01  5.13810664e-06
   1.18674076e+00  8.01788883e-06  5.18786255e-03 -5.18784765e-03]
 [ 1.32438585e-08 -6.90830994e+00 -1.08778477e-05  1.91585541e+01  5.14090061e-06
   1.18674052e+00  8.02161412e-06  5.18786255e-03 -5.18784765e-03]
 [ 1.32438585e-08 -6.90830994e+00 -1.08778477e-05  1.91585541e+01  5.14090061e-06
   1.18674052e+00  8.02161412e-06  5.18786255e-03 -5.18784765e-03]
 [ 1.32438602e-08 -6.90832138e+00 -1.08629465e-05  1.91585541e+01  5.13810664e-06
   1.18674076e+00  8.01788883e-06  5.18786255e-03 -5.18784765e-03]]
>>>
>>> # get finger joint generalized gravity forces: panda_finger_joint1 (7) and panda_finger_joint2 (8)
>>> # for the first, middle and last of the 5 envs. Returned shape is (3, 2)
>>> prims.get_generalized_gravity_forces(indices=np.array([0, 2, 4]), joint_indices=np.array([7, 8]))
[[ 0.00518786 -0.00518785]
 [ 0.00518786 -0.00518785]
 [ 0.00518786 -0.00518785]]
get_jacobian_shape() Union[numpy.ndarray, torch.Tensor, warp.types.array]

Get the Jacobian matrix shape of a single articulation

The Jacobian matrix maps the joint space velocities of a DOF to it’s cartesian and angular velocities

The shape of the Jacobian depends on the number of links (rigid bodies), DOFs, and whether the articulation base is fixed (e.g., robotic manipulators) or not (e.g,. mobile robots).

  • Fixed articulation base: (num_bodies - 1, 6, num_dof)

  • Non-fixed articulation base: (num_bodies, 6, num_dof + 6)

Each body has 6 values in the Jacobian representing its linear and angular motion along the three coordinate axes. The extra 6 DOFs in the last dimension, for non-fixed base cases, correspond to the linear and angular degrees of freedom of the free root link

Returns

shape of jacobian for a single articulation.

Return type

Union[np.ndarray, torch.Tensor, wp.array]

Example:

>>> # for the Franka Panda (a robotic manipulator with fixed base):
>>> # - num_bodies: 12
>>> # - num_dof: 9
>>> prims.get_jacobian_shape()
(11, 6, 9)
get_jacobians(indices: Optional[Union[numpy.ndarray, List, torch.Tensor, warp.types.array]] = None, clone: bool = True) Union[numpy.ndarray, torch.Tensor, warp.types.indexedarray]

Get the Jacobian matrices of articulations in the view

Note

The first dimension corresponds to the amount of wrapped articulations while the last 3 dimensions are the Jacobian matrix shape. Refer to the get_jacobian_shape method for details about the Jacobian matrix shape

Parameters
  • indices (Optional[Union[np.ndarray, List, torch.Tensor, wp.array]], optional) – indices to specify which prims to query. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

  • clone (bool, optional) – True to return a clone of the internal buffer. Otherwise False. Defaults to True.

Returns

Jacobian matrices of articulations in the view. Shape is (M, jacobian_shape).

Return type

Union[np.ndarray, torch.Tensor, wp.indexedarray]

Example:

>>> # get the Jacobian matrices. Returned shape is (5, 11, 6, 9) for the example: 5 envs, 12 links, 9 DOFs
>>> prims.get_jacobians()
[[[[ 4.2254178e-09  0.0000000e+00  0.0000000e+00 ...  0.0000000e+00  0.0000000e+00  0.0000000e+00]
   [ 1.2093576e-08  0.0000000e+00  0.0000000e+00 ...  0.0000000e+00  0.0000000e+00  0.0000000e+00]
   [-6.0873992e-16  0.0000000e+00  0.0000000e+00 ...  0.0000000e+00  0.0000000e+00  0.0000000e+00]
   [ 1.4458647e-07  0.0000000e+00  0.0000000e+00 ...  0.0000000e+00  0.0000000e+00  0.0000000e+00]
   [-1.8178657e-10  0.0000000e+00  0.0000000e+00 ...  0.0000000e+00  0.0000000e+00  0.0000000e+00]
   [ 9.9999976e-01  0.0000000e+00  0.0000000e+00 ...  0.0000000e+00  0.0000000e+00  0.0000000e+00]]
  ...
  [[-4.5089945e-02  8.1210062e-02 -3.8495898e-02 ...  2.8108317e-02  0.0000000e+00 -4.9317405e-02]
   [ 4.2863289e-01  9.7436900e-04  4.0475106e-01 ...  2.4577195e-03  0.0000000e+00  9.9807423e-01]
   [ 6.5973169e-09 -4.2914307e-01 -2.1542320e-02 ...  2.8352857e-02  0.0000000e+00 -3.7625343e-02]
   [ 1.4458647e-07 -1.1999309e-02 -5.3927803e-01 ...  7.0976764e-01  0.0000000e+00  0.0000000e+00]
   [-1.8178657e-10  9.9992776e-01 -6.4710006e-03 ...  8.5178167e-03  0.0000000e+00  0.0000000e+00]
   [ 9.9999976e-01 -3.8743019e-07  8.4210289e-01 ... -7.0438433e-01  0.0000000e+00  0.0000000e+00]]]]
get_joint_index(joint_name: str) int

Get a joint index in the joint buffers given its name

Parameters

joint_name (str) – name of the joint that corresponds to the index of the joint in the articulation

Returns

index of the joint in the joint buffers

Return type

int

get_joint_positions(indices: Optional[Union[numpy.ndarray, List, torch.Tensor, warp.types.array]] = None, joint_indices: Optional[Union[numpy.ndarray, List, torch.Tensor, warp.types.array]] = None, clone: bool = True) Union[numpy.ndarray, torch.Tensor, warp.types.indexedarray]

Get the joint positions of articulations in the view

Parameters
  • indices (Optional[Union[np.ndarray, List, torch.Tensor, wp.array]], optional) – indices to specify which prims to query. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

  • joint_indices (Optional[Union[np.ndarray, List, torch.Tensor, wp.array]], optional) – joint indices to specify which joints to query. Shape (K,). Where K <= num of dofs. Defaults to None (i.e: all dofs).

  • clone (bool, optional) – True to return a clone of the internal buffer. Otherwise False. Defaults to True.

Returns

joint positions of articulations in the view. Shape is (M, K).

Return type

Union[np.ndarray, torch.Tensor, wp.indexedarray]

Example:

>>> # get all joint positions. Returned shape is (5, 9) for the example: 5 envs, 9 DOFs
>>> prims.get_joint_positions()
[[ 1.1999921e-02 -5.6962633e-01  1.3219320e-08 -2.8105433e+00  6.8276213e-06
   3.0301569e+00  7.3234755e-01  3.9912373e-02  3.9999999e-02]
 [ 1.1999921e-02 -5.6962633e-01  1.3219320e-08 -2.8105433e+00  6.8276213e-06
   3.0301569e+00  7.3234755e-01  3.9912373e-02  3.9999999e-02]
 [ 1.1999921e-02 -5.6962633e-01  1.3220056e-08 -2.8105433e+00  6.8276104e-06
   3.0301569e+00  7.3234755e-01  3.9912373e-02  3.9999999e-02]
 [ 1.1999921e-02 -5.6962633e-01  1.3220056e-08 -2.8105433e+00  6.8276104e-06
   3.0301569e+00  7.3234755e-01  3.9912373e-02  3.9999999e-02]
 [ 1.1999921e-02 -5.6962633e-01  1.3219320e-08 -2.8105433e+00  6.8276213e-06
   3.0301569e+00  7.3234755e-01  3.9912373e-02  3.9999999e-02]]
>>>
>>> # get finger joint positions: panda_finger_joint1 (7) and panda_finger_joint2 (8)
>>> # for the first, middle and last of the 5 envs. Returned shape is (3, 2)
>>> prims.get_joint_positions(indices=np.array([0, 2, 4]), joint_indices=np.array([7, 8]))
[[0.03991237 0.04      ]
 [0.03991237 0.04      ]
 [0.03991237 0.04      ]]
get_joint_velocities(indices: Optional[Union[numpy.ndarray, List, torch.Tensor, warp.types.array]] = None, joint_indices: Optional[Union[numpy.ndarray, List, torch.Tensor, warp.types.array]] = None, clone: bool = True) Union[numpy.ndarray, torch.Tensor, warp.types.indexedarray]

Get the joint velocities of articulations in the view

Parameters
  • indices (Optional[Union[np.ndarray, List, torch.Tensor, wp.array]], optional) – indices to specify which prims to query. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

  • joint_indices (Optional[Union[np.ndarray, List, torch.Tensor, wp.array]], optional) – joint indices to specify which joints to query. Shape (K,). Where K <= num of dofs. Defaults to None (i.e: all dofs).

  • clone (bool, optional) – True to return a clone of the internal buffer. Otherwise False. Defaults to True.

Returns

joint velocities of articulations in the view. Shape is (M, K).

Return type

Union[np.ndarray, torch.Tensor, wp.indexedarray]

Example:

>>> # get all joint velocities. Returned shape is (5, 9) for the example: 5 envs, 9 DOFs
>>> prims.get_joint_velocities()
[[ 1.9010375e-06 -7.6763844e-03 -2.1396865e-07  1.1063669e-02 -4.6333633e-05
   3.4824573e-02  8.8469200e-02  5.4033857e-04  1.0287426e-05]
 [ 1.9010375e-06 -7.6763844e-03 -2.1396865e-07  1.1063669e-02 -4.6333633e-05
   3.4824573e-02  8.8469200e-02  5.4033857e-04  1.0287426e-05]
 [ 1.9010074e-06 -7.6763779e-03 -2.1403629e-07  1.1063648e-02 -4.6333400e-05
   3.4824558e-02  8.8469170e-02  5.4033566e-04  1.0287110e-05]
 [ 1.9010074e-06 -7.6763779e-03 -2.1403629e-07  1.1063648e-02 -4.6333400e-05
   3.4824558e-02  8.8469170e-02  5.4033566e-04  1.0287110e-05]
 [ 1.9010375e-06 -7.6763844e-03 -2.1396865e-07  1.1063669e-02 -4.6333633e-05
   3.4824573e-02  8.8469200e-02  5.4033857e-04  1.0287426e-05]]
>>>
>>> # get finger joint velocities: panda_finger_joint1 (7) and panda_finger_joint2 (8)
>>> # for the first, middle and last of the 5 envs. Returned shape is (3, 2)
>>> prims.get_joint_velocities(indices=np.array([0, 2, 4]), joint_indices=np.array([7, 8]))
[[5.4033857e-04 1.0287426e-05]
 [5.4033566e-04 1.0287110e-05]
 [5.4033857e-04 1.0287426e-05]]
get_joints_default_state() omni.isaac.core.utils.types.JointsState

Get the default joint states defined with the set_joints_default_state method

Returns

an object that contains the default joint states

Return type

JointsState

Example:

>>> # returned shape is (5, 9) for the example: 5 envs, 9 DOFs
>>> states = prims.get_joints_default_state()
>>> states
<omni.isaac.core.utils.types.JointsState object at 0x7fc2c174fd90>
>>> states.positions
[[ 0.   -1.    0.   -2.2   0.    2.4   0.8   0.04  0.04]
 [ 0.   -1.    0.   -2.2   0.    2.4   0.8   0.04  0.04]
 [ 0.   -1.    0.   -2.2   0.    2.4   0.8   0.04  0.04]
 [ 0.   -1.    0.   -2.2   0.    2.4   0.8   0.04  0.04]
 [ 0.   -1.    0.   -2.2   0.    2.4   0.8   0.04  0.04]]
>>> states.velocities
[[0. 0. 0. 0. 0. 0. 0. 0. 0.]
 [0. 0. 0. 0. 0. 0. 0. 0. 0.]
 [0. 0. 0. 0. 0. 0. 0. 0. 0.]
 [0. 0. 0. 0. 0. 0. 0. 0. 0.]
 [0. 0. 0. 0. 0. 0. 0. 0. 0.]]
>>> states.efforts
[[0. 0. 0. 0. 0. 0. 0. 0. 0.]
 [0. 0. 0. 0. 0. 0. 0. 0. 0.]
 [0. 0. 0. 0. 0. 0. 0. 0. 0.]
 [0. 0. 0. 0. 0. 0. 0. 0. 0.]
 [0. 0. 0. 0. 0. 0. 0. 0. 0.]]
get_joints_state() omni.isaac.core.utils.types.JointsState

Get the current joint states (positions and velocities)

Returns

an object that contains the current joint positions and velocities

Return type

JointsState

Example:

>>> # returned shape is (5, 9) for the example: 5 envs, 9 DOFs
>>> states = prims.get_joints_state()
>>> states
<omni.isaac.core.utils.types.JointsState object at 0x7fc1a23a82e0>
>>> states.positions
[[ 1.1999921e-02 -5.6962633e-01  1.3219320e-08 -2.8105433e+00  6.8276213e-06
   3.0301569e+00  7.3234755e-01  3.9912373e-02  3.9999999e-02]
 [ 1.1999921e-02 -5.6962633e-01  1.3219320e-08 -2.8105433e+00  6.8276213e-06
   3.0301569e+00  7.3234755e-01  3.9912373e-02  3.9999999e-02]
 [ 1.1999921e-02 -5.6962633e-01  1.3220056e-08 -2.8105433e+00  6.8276104e-06
   3.0301569e+00  7.3234755e-01  3.9912373e-02  3.9999999e-02]
 [ 1.1999921e-02 -5.6962633e-01  1.3220056e-08 -2.8105433e+00  6.8276104e-06
   3.0301569e+00  7.3234755e-01  3.9912373e-02  3.9999999e-02]
 [ 1.1999921e-02 -5.6962633e-01  1.3219320e-08 -2.8105433e+00  6.8276213e-06
   3.0301569e+00  7.3234755e-01  3.9912373e-02  3.9999999e-02]]
>>> states.velocities
[[ 1.9010375e-06 -7.6763844e-03 -2.1396865e-07  1.1063669e-02 -4.6333633e-05
   3.4824573e-02  8.8469200e-02  5.4033857e-04  1.0287426e-05]
 [ 1.9010375e-06 -7.6763844e-03 -2.1396865e-07  1.1063669e-02 -4.6333633e-05
   3.4824573e-02  8.8469200e-02  5.4033857e-04  1.0287426e-05]
 [ 1.9010074e-06 -7.6763779e-03 -2.1403629e-07  1.1063648e-02 -4.6333400e-05
   3.4824558e-02  8.8469170e-02  5.4033566e-04  1.0287110e-05]
 [ 1.9010074e-06 -7.6763779e-03 -2.1403629e-07  1.1063648e-02 -4.6333400e-05
   3.4824558e-02  8.8469170e-02  5.4033566e-04  1.0287110e-05]
 [ 1.9010375e-06 -7.6763844e-03 -2.1396865e-07  1.1063669e-02 -4.6333633e-05
   3.4824573e-02  8.8469200e-02  5.4033857e-04  1.0287426e-05]]
get_linear_velocities(indices: Optional[Union[numpy.ndarray, list, torch.Tensor, warp.types.array]] = None, clone=True) Union[numpy.ndarray, torch.Tensor, warp.types.indexedarray]

Get the linear velocities of prims in the view.

Parameters
  • indices (Optional[Union[np.ndarray, list, torch.Tensor, wp.array]], optional) – indices to specify which prims to query. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view)

  • clone (bool, optional) – True to return a clone of the internal buffer. Otherwise False. Defaults to True.

Returns

linear velocities of the prims in the view. shape is (M, 3).

Return type

Union[np.ndarray, torch.Tensor, wp.indexedarray]

Example:

>>> # get all articulation linear velocities. Returned shape is (5, 3) for the example: 5 envs, linear (3)
>>> prims.get_linear_velocities()
[[0. 0. 0.]
 [0. 0. 0.]
 [0. 0. 0.]
 [0. 0. 0.]
 [0. 0. 0.]]
>>>
>>> # get only the articulation linear velocities for the first, middle and last of the 5 envs.
>>> # Returned shape is (3, 3) for the example: 3 envs selected, linear (3)
>>> prims.get_linear_velocities(indices=np.array([0, 2, 4]))
[[0. 0. 0.]
 [0. 0. 0.]
 [0. 0. 0.]]

Get a link index in the link buffers given its name

Parameters

link_name (str) – name of the link that corresponds to the index of the link in the articulation

Returns

index of the link in the link buffers

Return type

int

get_local_poses(indices: Optional[Union[numpy.ndarray, list, torch.Tensor, warp.types.array]] = None) Union[Tuple[numpy.ndarray, numpy.ndarray], Tuple[torch.Tensor, torch.Tensor], Tuple[warp.types.indexedarray, warp.types.indexedarray]]

Get prim poses in the view with respect to the local frame (the prim’s parent frame).

Parameters

indices (Optional[Union[np.ndarray, list, torch.Tensor, wp.array]], optional) – indices to specify which prims to query. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view)

Returns

first index is positions in the local frame of the prims. shape is (M, 3). Second index is quaternion orientations in the local frame of the prims. Quaternion is scalar-first (w, x, y, z). shape is (M, 4).

Return type

Union[Tuple[np.ndarray, np.ndarray], Tuple[torch.Tensor, torch.Tensor], Tuple[wp.indexedarray, wp.indexedarray]]

Example:

>>> # get all articulation poses with respect to the local frame.
>>> # Returned shape is position (5, 3) and orientation (5, 4) for the example: 5 envs
>>> positions, orientations = prims.get_local_poses()
>>> positions
[[ 0.0000000e+00  0.0000000e+00 -2.8610229e-08]
 [ 0.0000000e+00  0.0000000e+00 -2.8610229e-08]
 [-4.5299529e-08  0.0000000e+00 -2.8610229e-08]
 [-4.5299529e-08  0.0000000e+00 -2.8610229e-08]
 [ 0.0000000e+00  0.0000000e+00 -2.8610229e-08]]
>>> orientations
[[1. 0. 0. 0.]
 [1. 0. 0. 0.]
 [1. 0. 0. 0.]
 [1. 0. 0. 0.]
 [1. 0. 0. 0.]]
>>>
>>> # get only the articulation poses with respect to the local frame for the first, middle and last of the 5 envs.
>>> # Returned shape is position (3, 3) and orientation (3, 4) for the example: 3 envs selected
>>> positions, orientations = prims.get_local_poses(indices=np.array([0, 2, 4]))
>>> positions
[[ 0.0000000e+00  0.0000000e+00 -2.8610229e-08]
 [-4.5299529e-08  0.0000000e+00 -2.8610229e-08]
 [ 0.0000000e+00  0.0000000e+00 -2.8610229e-08]]
>>> orientations
[[1. 0. 0. 0.]
 [1. 0. 0. 0.]
 [1. 0. 0. 0.]]
get_local_scales(indices: Optional[Union[numpy.ndarray, list, torch.Tensor, warp.types.array]] = None) Union[numpy.ndarray, torch.Tensor, warp.types.indexedarray]

Get prim scales in the view with respect to the local frame (the parent’s frame).

Parameters

indices (Optional[Union[np.ndarray, list, torch.Tensor, wp.array]], optional) – indices to specify which prims to query. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

Returns

scales applied to the prim’s dimensions in the local frame. shape is (M, 3).

Return type

Union[np.ndarray, torch.Tensor, wp.indexedarray]

Example:

>>> # get all prims scales with respect to the local frame.
>>> # Returned shape is (5, 3) for the example: 5 envs
>>> prims.get_local_scales()
[[1. 1. 1.]
 [1. 1. 1.]
 [1. 1. 1.]
 [1. 1. 1.]
 [1. 1. 1.]]
>>>
>>> # get only the prims scales with respect to the local frame for the first, middle and last of the 5 envs.
>>> # Returned shape is (3, 3) for the example: 3 envs selected
>>> prims.get_local_scales(indices=np.array([0, 2, 4]))
[[1. 1. 1.]
 [1. 1. 1.]
 [1. 1. 1.]]
get_mass_matrices(indices: Optional[Union[numpy.ndarray, List, torch.Tensor, warp.types.array]] = None, clone: bool = True) Union[numpy.ndarray, torch.Tensor, warp.types.indexedarray]

Get the mass matrices of articulations in the view

Note

The first dimension corresponds to the amount of wrapped articulations while the last 2 dimensions are the mass matrix shape. Refer to the get_mass_matrix_shape method for details about the mass matrix shape

Parameters
  • indices (Optional[Union[np.ndarray, List, torch.Tensor, wp.array]], optional) – indices to specify which prims to query. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

  • clone (bool, optional) – True to return a clone of the internal buffer. Otherwise False. Defaults to True.

Returns

mass matrices of articulations in the view. Shape is (M, mass_matrix_shape).

Return type

Union[np.ndarray, torch.Tensor, wp.indexedarray]

Example:

>>> # get the mass matrices. Returned shape is (5, 9, 9) for the example: 5 envs, 9 DOFs
>>> prims.get_mass_matrices()
[[[ 5.0900602e-01  1.1794259e-06  4.2570841e-01 -1.6387942e-06 -3.1573933e-02
   -1.9736715e-06 -3.1358242e-04 -6.0441834e-03  6.0441834e-03]
  [ 1.1794259e-06  1.0598221e+00  7.4729815e-07 -4.2621672e-01  2.3612277e-08
   -4.9647894e-02 -2.9080724e-07 -1.8432185e-04  1.8432130e-04]
  ...
  [-6.0441834e-03 -1.8432185e-04 -5.7159867e-03  4.0070520e-04  9.6930371e-04
    1.2324301e-04  2.5264668e-10  1.4055224e-02  0.0000000e+00]
  [ 6.0441834e-03  1.8432130e-04  5.7159867e-03 -4.0070404e-04 -9.6930366e-04
   -1.2324269e-04 -3.6906206e-10  0.0000000e+00  1.4055224e-02]]]
get_mass_matrix_shape() Union[numpy.ndarray, torch.Tensor, warp.types.array]

Get the mass matrix shape of a single articulation

The mass matrix contains the generalized mass of the robot depending on the current configuration

The shape of the max matrix depends on the number of DOFs: (num_dof, num_dof)

Returns

shape of mass matrix for a single articulation.

Return type

Union[np.ndarray, torch.Tensor, wp.array]

Example:

>>> # for the Franka Panda:
>>> # - num_dof: 9
>>> prims.get_jacobian_shape()
(9, 9)
get_max_efforts(indices: Optional[Union[numpy.ndarray, List, torch.Tensor, warp.types.array]] = None, joint_indices: Optional[Union[numpy.ndarray, List, torch.Tensor, warp.types.array]] = None, clone: bool = True) Union[numpy.ndarray, torch.Tensor, warp.types.indexedarray]

Get the maximum efforts for articulation in the view

Parameters
  • indices (Optional[Union[np.ndarray, List, torch.Tensor, wp.array]], optional) – indices to specify which prims to query. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

  • joint_indices (Optional[Union[np.ndarray, List, torch.Tensor, wp.array]], optional) – joint indices to specify which joints to query. Shape (K,). Where K <= num of dofs. Defaults to None (i.e: all dofs).

  • clone (Optional[bool]) – True to return a clone of the internal buffer. Otherwise False. Defaults to True.

Returns

maximum efforts for articulations in the view. shape (M, K).

Return type

Union[np.ndarray, torch.Tensor, wp.indexedarray]

Example:

>>> # get all joint maximum efforts. Returned shape is (5, 9) for the example: 5 envs, 9 DOFs
>>> prims.get_max_efforts()
[[5220. 5220. 5220. 5220.  720.  720.  720.  720.  720.]
 [5220. 5220. 5220. 5220.  720.  720.  720.  720.  720.]
 [5220. 5220. 5220. 5220.  720.  720.  720.  720.  720.]
 [5220. 5220. 5220. 5220.  720.  720.  720.  720.  720.]
 [5220. 5220. 5220. 5220.  720.  720.  720.  720.  720.]]
>>>
>>> # get finger joint maximum efforts: panda_finger_joint1 (7) and panda_finger_joint2 (8)
>>> # for the first, middle and last of the 5 envs. Returned shape is (3, 2)
>>> prims.get_max_efforts(indices=np.array([0, 2, 4]), joint_indices=np.array([7, 8]))
[[720. 720.]
 [720. 720.]
 [720. 720.]]
get_measured_joint_efforts(indices: Optional[Union[numpy.ndarray, List, torch.Tensor, warp.types.array]] = None, joint_indices: Optional[Union[numpy.ndarray, List, torch.Tensor, warp.types.array]] = None, clone: bool = True) Union[numpy.ndarray, torch.Tensor, warp.types.indexedarray]

Returns the efforts computed/measured by the physics solver of the joint forces in the DOF motion direction

Parameters
  • indices (Optional[Union[np.ndarray, List, torch.Tensor]], optional) – indices to specify which prims to query. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

  • joint_indices (Optional[Union[np.ndarray, List, torch.Tensor]], optional) – joint indices to specify which joints to query. Shape (K,). Where K <= num of dofs. Defaults to None (i.e: all dofs).

  • clone (bool, optional) – True to return a clone of the internal buffer. Otherwise False. Defaults to True.

Returns

computed joint efforts of articulations in the view. shape is (M, K).

Return type

Union[np.ndarray, torch.Tensor]

Example:

>>> # get all measured joint efforts. Returned shape is (5, 9) for the example: 5 envs, 9 DOFs
>>> prims.get_measured_joint_efforts()
[[ 4.8250298e-05 -6.9073005e+00  5.3364405e-05  1.9157070e+01 -5.8759182e-05
   1.1863427e+00 -5.6388220e-05  5.1680300e-03 -5.1910817e-03]
 [ 4.8250298e-05 -6.9073005e+00  5.3364405e-05  1.9157070e+01 -5.8759182e-05
   1.1863427e+00 -5.6388220e-05  5.1680300e-03 -5.1910817e-03]
 [ 4.8254540e-05 -6.9072919e+00  5.3344327e-05  1.9157072e+01 -5.8761045e-05
   1.1863427e+00 -5.6405144e-05  5.1680212e-03 -5.1910840e-03]
 [ 4.8254540e-05 -6.9072919e+00  5.3344327e-05  1.9157072e+01 -5.8761045e-05
   1.1863427e+00 -5.6405144e-05  5.1680212e-03 -5.1910840e-03]
 [ 4.8250298e-05 -6.9073005e+00  5.3364405e-05  1.9157070e+01 -5.8759182e-05
   1.1863427e+00 -5.6388220e-05  5.1680300e-03  -5.1910817e-03]]
>>>
>>> # get finger measured joint efforts: panda_finger_joint1 (7) and panda_finger_joint2 (8)
>>> # for the first, middle and last of the 5 envs. Returned shape is (3, 2)
>>> prims.get_measured_joint_efforts(indices=np.array([0, 2, 4]), joint_indices=np.array([7, 8]))
[[ 0.00516803 -0.00519108]
 [ 0.00516802 -0.00519108]
 [ 0.00516803 -0.00519108]]
get_measured_joint_forces(indices: Optional[Union[numpy.ndarray, List, torch.Tensor]] = None, joint_indices: Optional[Union[numpy.ndarray, List, torch.Tensor]] = None, clone: bool = True) Union[numpy.ndarray, torch.Tensor]

Get the measured joint reaction forces and torques (link incoming joint forces and torques) to external loads

Note

Since the name->index map for joints has not been exposed yet, it is possible to access the joint names and their indices through the articulation metadata.

prims._metadata.joint_names  # list of names
prims._metadata.joint_indices  # dict of name: index

To retrieve a specific row for the link incoming joint force/torque use joint_index + 1

Parameters
  • indices (Optional[Union[np.ndarray, List, torch.Tensor]], optional) – indices to specify which prims to query. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

  • joint_indices (Optional[Union[np.ndarray, List, torch.Tensor]], optional) – link indices to specify which link’s incoming joints to query. Shape (K,). Where K <= num of links/bodies. Defaults to None (i.e: all dofs).

  • clone (bool, optional) – True to return a clone of the internal buffer. Otherwise False. Defaults to True.

Returns

joint forces and torques of articulations in the view. Shape is (M, num_joint + 1, 6). Column index 0 is the incoming joint of the base link. For the last dimension the first 3 values are for forces and the last 3 for torques

Return type

Union[np.ndarray, torch.Tensor]

Example:

>>> # get all measured joint forces and torques. Returned shape is (5, 12, 6) for the example:
>>> # 5 envs, 9 DOFs (but 12 joints including the fixed and root joints)
>>> prims.get_measured_joint_forces()
[[[ 0.00000000e+00  0.00000000e+00  0.00000000e+00  0.00000000e+00  0.00000000e+00  0.00000000e+00]
  [ 1.49950760e+02  3.52353277e-06  5.62586996e-04  4.82502983e-05 -6.90729856e+00  2.69259126e-05]
  [-2.60467059e-05 -1.06778236e+02 -6.83844986e+01 -6.90730047e+00 -5.27759657e-05 -1.24897576e-06]
  [ 8.71209946e+01 -4.46646191e-05 -5.57951622e+01  5.33644052e-05 -2.45385647e+01  1.38957939e-05]
  [ 5.18576926e-05 -4.81099091e+01  6.07092705e+01  1.91570702e+01 -5.81023924e-05  1.46875891e-06]
  [-3.16910419e+01  2.31799815e-04  3.99901695e+01 -5.87591821e-05 -1.18634319e+00  2.24427877e-05]
  [-1.07621672e-04  1.53405371e+01 -1.54584875e+01  1.18634272e+00  6.09036942e-05 -1.60679410e-05]
  [-7.54189777e+00 -5.08146524e+00 -5.65130091e+00 -5.63882204e-05  3.88599992e-01 -3.49432468e-01]
  [ 4.74214745e+00 -3.19458222e+00  3.55281782e+00  5.58562024e-05  8.47946014e-03  7.64050474e-03]
  [ 4.07607269e+00  2.16406956e-01 -4.05131817e+00 -5.95658377e-04  1.14070829e-02  2.13965313e-06]
  [ 5.16803004e-03 -9.77545828e-02 -9.70939621e-02 -8.41282599e-12 -1.29066744e-12 -1.93477560e-11]
  [-5.19108167e-03  9.75882635e-02 -9.71064270e-02  8.41282859e-12  1.29066018e-12 -1.93477543e-11]]
 ...
 [[ 0.00000000e+00  0.00000000e+00  0.00000000e+00  0.00000000e+00  0.00000000e+00  0.00000000e+00]
  [ 1.49950760e+02  3.52353277e-06  5.62586996e-04  4.82502983e-05 -6.90729856e+00  2.69259126e-05]
  [-2.60467059e-05 -1.06778236e+02 -6.83844986e+01 -6.90730047e+00 -5.27759657e-05 -1.24897576e-06]
  [ 8.71209946e+01 -4.46646191e-05 -5.57951622e+01  5.33644052e-05 -2.45385647e+01  1.38957939e-05]
  [ 5.18576926e-05 -4.81099091e+01  6.07092705e+01  1.91570702e+01 -5.81023924e-05  1.46875891e-06]
  [-3.16910419e+01  2.31799815e-04  3.99901695e+01 -5.87591821e-05 -1.18634319e+00  2.24427877e-05]
  [-1.07621672e-04  1.53405371e+01 -1.54584875e+01  1.18634272e+00  6.09036942e-05 -1.60679410e-05]
  [-7.54189777e+00 -5.08146524e+00 -5.65130091e+00 -5.63882204e-05  3.88599992e-01 -3.49432468e-01]
  [ 4.74214745e+00 -3.19458222e+00  3.55281782e+00  5.58562024e-05  8.47946014e-03  7.64050474e-03]
  [ 4.07607269e+00  2.16406956e-01 -4.05131817e+00 -5.95658377e-04  1.14070829e-02  2.13965313e-06]
  [ 5.16803004e-03 -9.77545828e-02 -9.70939621e-02 -8.41282599e-12 -1.29066744e-12 -1.93477560e-11]
  [-5.19108167e-03  9.75882635e-02 -9.71064270e-02  8.41282859e-12  1.29066018e-12 -1.93477543e-11]]]
>>>
>>> # get measured joint forces and torques for the fingers for the first, middle and last of the 5 envs.
>>> # Returned shape is (3, 2, 6)
>>> metadata = prims._metadata
>>> joint_indices = 1 + np.array([
>>>     metadata.joint_indices["panda_finger_joint1"],
>>>     metadata.joint_indices["panda_finger_joint2"],
>>> ])
>>> joint_indices
[10 11]
>>> prims.get_measured_joint_forces(indices=np.array([0, 2, 4]), joint_indices=joint_indices)
[[[ 5.1680300e-03 -9.7754583e-02 -9.7093962e-02 -8.4128260e-12 -1.2906674e-12 -1.9347756e-11]
  [-5.1910817e-03  9.7588263e-02 -9.7106427e-02  8.4128286e-12  1.2906602e-12 -1.9347754e-11]]
 [[ 5.1680212e-03 -9.7754560e-02 -9.7093947e-02 -8.4141834e-12 -1.2907383e-12 -1.9348209e-11]
  [-5.1910840e-03  9.7588278e-02 -9.7106412e-02  8.4141869e-12  1.2907335e-12 -1.9348207e-11]]
 [[ 5.1680300e-03 -9.7754583e-02 -9.7093962e-02 -8.4128260e-12 -1.2906674e-12 -1.9347756e-11]
  [-5.1910817e-03  9.7588263e-02 -9.7106427e-02  8.4128286e-12  1.2906602e-12 -1.9347754e-11]]]
get_sleep_thresholds(indices: Optional[Union[numpy.ndarray, List, torch.Tensor, warp.types.array]] = None) Union[numpy.ndarray, torch.Tensor, warp.types.indexedarray]

Get the threshold for articulations to enter a sleep state

Search for Articulations and Sleeping in PhysX docs for more details

Parameters

indices (Optional[Union[np.ndarray, List, torch.Tensor, wp.array]], optional) – indices to specify which prims to query. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

Returns

sleep thresholds. shape (M,).

Return type

Union[np.ndarray, torch.Tensor, wp.indexedarray]

Example:

>>> # get all sleep thresholds. Returned shape is (5,) for the example: 5 envs
>>> prims.get_sleep_thresholds()
[0.005 0.005 0.005 0.005 0.005]
>>>
>>> # get the sleep thresholds for the first, middle and last of the 5 envs. Returned shape is (3,)
>>> prims.get_sleep_thresholds(indices=np.array([0, 2, 4]))
[0.005 0.005 0.005]
get_solver_position_iteration_counts(indices: Optional[Union[numpy.ndarray, List, torch.Tensor, warp.types.array]] = None) Union[numpy.ndarray, torch.Tensor, warp.types.indexedarray]

Get the solver (position) iteration count for the articulations

The solver iteration count determines how accurately contacts, drives, and limits are resolved. Search for Solver Iteration Count in PhysX docs for more details.

Parameters

indices (Optional[Union[np.ndarray, List, torch.Tensor, wp.array]], optional) – indices to specify which prims to query. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

Returns

position iteration count. Shape (M,).

Return type

Union[np.ndarray, torch.Tensor, wp.indexedarray]

Example:

>>> # get all position iteration count. Returned shape is (5,) for the example: 5 envs
>>> prims.get_solver_position_iteration_counts()
[32 32 32 32 32]
>>>
>>> # get the position iteration count for the first, middle and last of the 5 envs. Returned shape is (3,)
>>> prims.get_solver_position_iteration_counts(indices=np.array([0, 2, 4]))
[32 32 32]
get_solver_velocity_iteration_counts(indices: Optional[Union[numpy.ndarray, List, torch.Tensor, warp.types.array]] = None) Union[numpy.ndarray, torch.Tensor, warp.types.indexedarray]

Get the solver (velocity) iteration count for the articulations

The solver iteration count determines how accurately contacts, drives, and limits are resolved. Search for Solver Iteration Count in PhysX docs for more details.

Parameters

indices (Optional[Union[np.ndarray, List, torch.Tensor, wp.array]], optional) – indices to specify which prims to query. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

Returns

velocity iteration count. Shape (M,).

Return type

Union[np.ndarray, torch.Tensor, wp.indexedarray]

Example:

>>> # get all velocity iteration count. Returned shape is (5,) for the example: 5 envs
>>> prims.get_solver_velocity_iteration_counts()
[32 32 32 32 32]
>>>
>>> # get the velocity iteration count for the first, middle and last of the 5 envs. Returned shape is (3,)
>>> prims.get_solver_velocity_iteration_counts(indices=np.array([0, 2, 4]))
[32 32 32]
get_stabilization_thresholds(indices: Optional[Union[numpy.ndarray, List, torch.Tensor, warp.types.array]] = None) Union[numpy.ndarray, torch.Tensor, warp.types.indexedarray]

Get the mass-normalized kinetic energy below which the articulations may participate in stabilization

Search for Stabilization Threshold in PhysX docs for more details

Parameters

indices (Optional[Union[np.ndarray, List, torch.Tensor, wp.array]], optional) – indices to specify which prims to query. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

Returns

stabilization threshold. Shape (M,).

Return type

Union[np.ndarray, torch.Tensor, wp.indexedarray]

Example:

>>> # get all stabilization thresholds. Returned shape is (5,) for the example: 5 envs
>>> prims.get_solver_velocity_iteration_counts()
[0.001 0.001 0.001 0.001 0.001]
>>>
>>> # get the stabilization thresholds for the first, middle and last of the 5 envs. Returned shape is (3,)
>>> prims.get_solver_velocity_iteration_counts(indices=np.array([0, 2, 4]))
[0.001 0.001 0.001]
get_velocities(indices: Optional[Union[numpy.ndarray, list, torch.Tensor, warp.types.array]] = None, clone: bool = True) Union[numpy.ndarray, torch.Tensor, warp.types.indexedarray]

Get the linear and angular velocities of prims in the view.

Parameters
  • indices (Optional[Union[np.ndarray, list, torch.Tensor, wp.array]], optional) – indices to specify which prims to query. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view)

  • clone (bool, optional) – True to return a clone of the internal buffer. Otherwise False. Defaults to True.

Returns

linear and angular velocities of the prims in the view concatenated. shape is (M, 6). For the last dimension the first 3 values are for linear velocities and the last 3 for angular velocities

Return type

Union[np.ndarray, torch.Tensor, wp.indexedarray]

Example:

>>> # get all articulation velocities. Returned shape is (5, 6) for the example: 5 envs, linear (3) and angular (3)
>>> prims.get_velocities()
[[0. 0. 0. 0. 0. 0.]
 [0. 0. 0. 0. 0. 0.]
 [0. 0. 0. 0. 0. 0.]
 [0. 0. 0. 0. 0. 0.]
 [0. 0. 0. 0. 0. 0.]]
>>>
>>> # get only the articulation velocities for the first, middle and last of the 5 envs.
>>> # Returned shape is (3, 6) for the example: 3 envs selected, linear (3) and angular (3)
>>> prims.get_velocities(indices=np.array([0, 2, 4]))
[[0. 0. 0. 0. 0. 0.]
 [0. 0. 0. 0. 0. 0.]
 [0. 0. 0. 0. 0. 0.]]
get_visibilities(indices: Optional[Union[numpy.ndarray, list, torch.Tensor, warp.types.array]] = None) Union[numpy.ndarray, torch.Tensor, warp.types.indexedarray]

Returns the current visibilities of the prims in stage.

Parameters

indices (Optional[Union[np.ndarray, list, torch.Tensor, wp.array]], optional) – indices to specify which prims to query. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

Returns

Shape (M,) with type bool, where each item holds True

if the prim is visible in stage. False otherwise.

Return type

Union[np.ndarray, torch.Tensor, wp.indexedarray]

Example:

>>> # get all visibilities. Returned shape is (5,) for the example: 5 envs
>>> prims.get_visibilities()
[ True  True  True  True  True]
>>>
>>> # get the visibilities for the first, middle and last of the 5 envs. Returned shape is (3,)
>>> prims.get_visibilities(indices=np.array([0, 2, 4]))
[ True  True  True]
get_world_poses(indices: Optional[Union[numpy.ndarray, list, torch.Tensor, warp.types.array]] = None, clone: bool = True) Union[Tuple[numpy.ndarray, numpy.ndarray], Tuple[torch.Tensor, torch.Tensor], Tuple[warp.types.indexedarray, warp.types.indexedarray]]

Get the poses of the prims in the view with respect to the world’s frame.

Parameters
  • indices (Optional[Union[np.ndarray, list, torch.Tensor, wp.array]], optional) – indices to specify which prims to query. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

  • clone (bool, optional) – True to return a clone of the internal buffer. Otherwise False. Defaults to True.

Returns

first index is positions in the world frame of the prims. shape is (M, 3). Second index is quaternion orientations in the world frame of the prims. Quaternion is scalar-first (w, x, y, z). shape is (M, 4).

Return type

Union[Tuple[np.ndarray, np.ndarray], Tuple[torch.Tensor, torch.Tensor], Tuple[wp.indexedarray, wp.indexedarray]]

Example:

>>> # get all articulation poses with respect to the world's frame.
>>> # Returned shape is position (5, 3) and orientation (5, 4) for the example: 5 envs
>>> positions, orientations = prims.get_world_poses()
>>> positions
[[ 1.5000000e+00 -7.5000000e-01 -2.8610229e-08]
 [ 1.5000000e+00  7.5000000e-01 -2.8610229e-08]
 [-4.5299529e-08 -7.5000000e-01 -2.8610229e-08]
 [-4.5299529e-08  7.5000000e-01 -2.8610229e-08]
 [-1.5000000e+00 -7.5000000e-01 -2.8610229e-08]]
>>> orientations
[[1. 0. 0. 0.]
 [1. 0. 0. 0.]
 [1. 0. 0. 0.]
 [1. 0. 0. 0.]
 [1. 0. 0. 0.]]
>>>
>>> # get only the articulation poses with respect to the world's frame for the first, middle and last of the 5 envs.
>>> # Returned shape is position (3, 3) and orientation (3, 4) for the example: 3 envs selected
>>> positions, orientations = prims.get_world_poses(indices=np.array([0, 2, 4]))
>>> positions
[[ 1.5000000e+00 -7.5000000e-01 -2.8610229e-08]
 [-4.5299529e-08 -7.5000000e-01 -2.8610229e-08]
 [-1.5000000e+00 -7.5000000e-01 -2.8610229e-08]]
>>> orientations
[[1. 0. 0. 0.]
 [1. 0. 0. 0.]
 [1. 0. 0. 0.]]
get_world_scales(indices: Optional[Union[numpy.ndarray, list, torch.Tensor, warp.types.array]] = None) Union[numpy.ndarray, torch.Tensor, warp.types.indexedarray]

Get prim scales in the view with respect to the world’s frame

Parameters

indices (Optional[Union[np.ndarray, list, torch.Tensor, wp.array]], optional) – indices to specify which prims to query. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

Returns

scales applied to the prim’s dimensions in the world frame. shape is (M, 3).

Return type

Union[np.ndarray, torch.Tensor, wp.indexedarray]

Example:

>>> # get all prims scales with respect to the world's frame.
>>> # Returned shape is (5, 3) for the example: 5 envs
>>> prims.get_world_scales()
[[1. 1. 1.]
 [1. 1. 1.]
 [1. 1. 1.]
 [1. 1. 1.]
 [1. 1. 1.]]
>>>
>>> # get only the prims scales with respect to the world's frame for the first, middle and last of the 5 envs.
>>> # Returned shape is (3, 3) for the example: 3 envs selected
>>> prims.get_world_scales(indices=np.array([0, 2, 4]))
[[1. 1. 1.]
 [1. 1. 1.]
 [1. 1. 1.]]
initialize(physics_sim_view: Optional[omni.physics.tensors.bindings._physicsTensors.SimulationView] = None) None

Create a physics simulation view if not passed and set other properties using the PhysX tensor API

Note

If the articulation view has been added to the world scene (e.g., world.scene.add(prims)), it will be automatically initialized when the world is reset (e.g., world.reset()).

Warning

This method needs to be called after each hard reset (e.g., Stop + Play on the timeline) before interacting with any other class method.

Parameters

physics_sim_view (omni.physics.tensors.SimulationView, optional) – current physics simulation view. Defaults to None.

Example:

>>> prims.initialize()
property initialized: bool

Check if articulation view is initialized

Returns

True if the view object was initialized (after the first call of .initialize()). False otherwise.

Return type

bool

Example:

>>> # given an initialized articulation view
>>> prims.initialized
True

Returns: bool: True if the prim corresponds to a non root link in an articulation. Otherwise False.

is_physics_handle_valid() bool

Check if articulation view’s physics handler is initialized

Warning

If the physics handler is not valid many of the methods that requires PhysX will return None.

Returns

False if .initialize() needs to be called again for the physics handle to be valid. Otherwise True

Return type

bool

Example:

>>> prims.is_physics_handle_valid()
True
is_valid(indices: Optional[Union[numpy.ndarray, list, torch.Tensor, warp.types.array]] = None) bool

Check that all prims have a valid USD Prim

Parameters

indices (Optional[Union[np.ndarray, list, torch.Tensor, wp.array]], optional) – indices to specify which prims to query. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

Returns

True if all prim paths specified in the view correspond to a valid prim in stage. False otherwise.

Return type

bool

Example:

>>> prims.is_valid()
True
is_visual_material_applied(indices: Optional[Union[numpy.ndarray, list, torch.Tensor, warp.types.array]] = None) List[bool]

Check if there is a visual material applied

Parameters

indices (Optional[Union[np.ndarray, list, torch.Tensor, wp.array]], optional) – indices to specify which prims to query. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

Returns

True if there is a visual material applied is applied to the corresponding prim in the view. False otherwise.

Return type

List[bool]

Example:

>>> # given a visual material that is applied only to the first and the last environment
>>> prims.is_visual_material_applied()
[True, False, False, False, True]
>>>
>>> # check for the first, middle and last of the 5 envs
>>> prims.is_visual_material_applied(indices=np.array([0, 2, 4]))
[True, False, True]
property joint_names: List[str]

List of prim names for each joint of the articulations

Returns

ordered names of joints that corresponds to degrees of freedom for the articulations in the view

Return type

List[str]

property name: str

Returns: str: name given to the prims view when instantiating it.

property num_bodies: int

Number of rigid bodies (links) of the articulations

Returns

maximum number of rigid bodies for the articulations in the view

Return type

int

Example:

>>> prims.num_bodies
12
property num_dof: int

Number of DOF of the articulations

Returns

maximum number of DOFs for the articulations in the view

Return type

int

Example:

>>> prims.num_dof
9
property num_fixed_tendons: int

Number of fixed tendons of the articulations

Returns

maximum number of fixed tendons for the articulations in the view

Return type

int

Example:

>>> prims.num_fixed_tendons
0
property num_joints: int

Number of joints of the articulations

Returns

number of joints of the articulations in the view

Return type

int

property num_shapes: int

Number of rigid shapes of the articulations

Returns

maximum number of rigid shapes for the articulations in the view

Return type

int

Example:

>>> prims.num_shapes
17
post_reset() None

Reset the articulations to their default states

Note

For the articulations, in addition to configuring the root prim’s default positions and spatial orientations (defined via the set_default_state method), the joint’s positions, velocities, and efforts (defined via the set_joints_default_state method) and the joint stiffnesses and dampings (defined via the set_gains method) are imposed

Example:

>>> prims.post_reset()
property prim_paths: List[str]
Returns

list of prim paths in the stage encapsulated in this view.

Return type

List[str]

Example:

>>> prims.prim_paths
['/World/envs/env_0', '/World/envs/env_1', '/World/envs/env_2', '/World/envs/env_3', '/World/envs/env_4']
property prims: List[pxr.Usd.Prim]
Returns

List of USD Prim objects encapsulated in this view.

Return type

List[Usd.Prim]

Example:

>>> prims.prims
[Usd.Prim(</World/envs/env_0>), Usd.Prim(</World/envs/env_1>), Usd.Prim(</World/envs/env_2>),
 Usd.Prim(</World/envs/env_3>), Usd.Prim(</World/envs/env_4>)]
set_angular_velocities(velocities: Optional[Union[numpy.ndarray, torch.Tensor, warp.types.array]] = None, indices: Optional[Union[numpy.ndarray, list, torch.Tensor, warp.types.array]] = None) None

Set the angular velocities of the prims in the view

The method does this through the physx API only. It has to be called after initialization. Note: This method is not supported for the gpu pipeline. set_velocities method should be used instead.

Warning

This method will immediately set the articulation state

Parameters
  • velocities (Optional[Union[np.ndarray, torch.Tensor, wp.array]]) – angular velocities to set the rigid prims to. shape is (M, 3).

  • indices (Optional[Union[np.ndarray, list, torch.Tensor, wp.array]], optional) – indices to specify which prims to manipulate. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

Hint

This method belongs to the methods used to set the articulation kinematic state:

set_velocities (set_linear_velocities, set_angular_velocities), set_joint_positions, set_joint_velocities, set_joint_efforts

Example:

>>> # set each articulation linear velocity to (0.1, 0.1, 0.1)
>>> velocities = np.full((num_envs, 3), fill_value=0.1)
>>> prims.set_angular_velocities(velocities)
>>>
>>> # set only the articulation linear velocities for the first, middle and last of the 5 envs
>>> velocities = np.full((3, 3), fill_value=0.1)
>>> prims.set_angular_velocities(velocities, indices=np.array([0, 2, 4]))
set_armatures(values: Union[numpy.ndarray, torch.Tensor, warp.types.array], indices: Optional[Union[numpy.ndarray, List, torch.Tensor, warp.types.array]] = None, joint_indices: Optional[Union[numpy.ndarray, List, torch.Tensor, warp.types.array]] = None) None

Set armatures for articulation joints in the view

Search for “Joint Armature” in PhysX docs for more details.

Parameters
  • values (Union[np.ndarray, torch.Tensor, wp.array]) – armatures for articulation joints in the view. shape (M, K).

  • indices (Optional[Union[np.ndarray, List, torch.Tensor, wp.array]], optional) – indices to specify which prims to manipulate. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

  • joint_indices (Optional[Union[np.ndarray, List, torch.Tensor, wp.array]], optional) – joint indices to specify which joints to manipulate. Shape (K,). Where K <= num of dofs. Defaults to None (i.e: all dofs).

Example:

>>> # set all joint armatures to 0.05 for all envs
>>> prims.set_armatures(np.full((num_envs, prims.num_dof), 0.05))
>>>
>>> # set only the finger joint (panda_finger_joint1 (7) and panda_finger_joint2 (8)) armatures
>>> # for the first, middle and last of the 5 envs to 0.05
>>> prims.set_armatures(np.full((3, 2), 0.05), indices=np.array([0,2,4]), joint_indices=np.array([7,8]))
set_body_coms(positions: Optional[Union[numpy.ndarray, torch.Tensor, warp.types.array]] = None, orientations: Optional[Union[numpy.ndarray, torch.Tensor, warp.types.array]] = None, indices: Optional[Union[numpy.ndarray, List, torch.Tensor, warp.types.array]] = None, body_indices: Optional[Union[numpy.ndarray, List, torch.Tensor, warp.types.array]] = None) None

Set body center of mass (COM) positions and orientations for articulation bodies in the view.

Parameters
  • positions (Union[np.ndarray, torch.Tensor, wp.array]) – body center of mass positions for articulations in the view. shape (M, K, 3).

  • orientations (Union[np.ndarray, torch.Tensor, wp.array]) – body center of mass orientations for articulations in the view. shape (M, K, 4).

  • indices (Optional[Union[np.ndarray, List, torch.Tensor, wp.array]], optional) – indices to specify which prims to manipulate. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

  • body_indices (Optional[Union[np.ndarray, List, torch.Tensor, wp.array]], optional) – body indices to specify which bodies to manipulate. Shape (K,). Where K <= num of bodies. Defaults to None (i.e: all bodies).

Example:

>>> # set the center of mass for all the articulation rigid bodies to the indicated values.
>>> # Since there are 5 envs, the inertias are repeated 5 times
>>> positions = np.tile(np.array([0.01, 0.02, 0.03]), (num_envs, prims.num_bodies, 1))
>>> orientations = np.tile(np.array([1.0, 0.0, 0.0, 0.0]), (num_envs, prims.num_bodies, 1))
>>> prims.set_body_coms(positions, orientations)
>>>
>>> # set the fingers center of mass: panda_leftfinger (10) and panda_rightfinger (11) to 0.2
>>> # for the first, middle and last of the 5 envs
>>> positions = np.tile(np.array([0.01, 0.02, 0.03]), (3, 2, 1))
>>> orientations = np.tile(np.array([1.0, 0.0, 0.0, 0.0]), (3, 2, 1))
>>> prims.set_body_coms(positions, orientations, indices=np.array([0, 2, 4]), body_indices=np.array([10, 11]))
set_body_inertias(values: Union[numpy.ndarray, torch.Tensor, warp.types.array], indices: Optional[Union[numpy.ndarray, List, torch.Tensor, warp.types.array]] = None, body_indices: Optional[Union[numpy.ndarray, List, torch.Tensor, warp.types.array]] = None) None

Set body inertias for articulation bodies in the view.

Parameters
  • values (Union[np.ndarray, torch.Tensor, wp.array]) – body inertias for articulations in the view. shape (M, K, 9).

  • indices (Optional[Union[np.ndarray, List, torch.Tensor, wp.array]], optional) – indices to specify which prims to manipulate. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

  • body_indices (Optional[Union[np.ndarray, List, torch.Tensor, wp.array]], optional) – body indices to specify which bodies to manipulate. Shape (K,). Where K <= num of bodies. Defaults to None (i.e: all bodies).

Example:

>>> # set the inertias for all the articulation rigid bodies to the indicated values.
>>> # Since there are 5 envs, the inertias are repeated 5 times
>>> inertias = np.tile(np.array([0.1, 0.0, 0.0, 0.0, 0.1, 0.0, 0.0, 0.0, 0.1]), (num_envs, prims.num_bodies, 1))
>>> prims.set_body_inertias(inertias)
>>>
>>> # set the fingers inertias: panda_leftfinger (10) and panda_rightfinger (11) to 0.2
>>> # for the first, middle and last of the 5 envs
>>> inertias = np.tile(np.array([0.1, 0.0, 0.0, 0.0, 0.1, 0.0, 0.0, 0.0, 0.1]), (3, 2, 1))
>>> prims.set_body_inertias(inertias, indices=np.array([0, 2, 4]), body_indices=np.array([10, 11]))
set_body_masses(values: Union[numpy.ndarray, torch.Tensor, warp.types.array], indices: Optional[Union[numpy.ndarray, List, torch.Tensor, warp.types.array]] = None, body_indices: Optional[Union[numpy.ndarray, List, torch.Tensor, warp.types.array]] = None) None

Set body masses for articulation bodies in the view

Parameters
  • values (Union[np.ndarray, torch.Tensor, wp.array]) – body masses for articulations in the view. shape (M, K).

  • indices (Optional[Union[np.ndarray, List, torch.Tensor, wp.array]], optional) – indices to specify which prims to manipulate. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

  • body_indices (Optional[Union[np.ndarray, List, torch.Tensor, wp.array]], optional) – body indices to specify which bodies to manipulate. Shape (K,). Where K <= num of bodies. Defaults to None (i.e: all bodies).

Example:

>>> # set the masses for all the articulation rigid bodies to the indicated values.
>>> # Since there are 5 envs, the masses are repeated 5 times
>>> masses = np.tile(np.array([1.2, 1.1, 1.0, 0.9, 0.8, 0.7, 0.6, 0.5, 0.4, 0.3, 0.2, 0.2]), (num_envs, 1))
>>> prims.set_body_masses(masses)
>>>
>>> # set the fingers masses: panda_leftfinger (10) and panda_rightfinger (11) to 0.2
>>> # for the first, middle and last of the 5 envs
>>> masses = np.tile(np.array([0.2, 0.2]), (3, 1))
>>> prims.set_body_masses(masses, indices=np.array([0, 2, 4]), body_indices=np.array([10, 11]))
set_default_state(positions: Optional[Union[numpy.ndarray, torch.Tensor, warp.types.array]] = None, orientations: Optional[Union[numpy.ndarray, torch.Tensor, warp.types.array]] = None, indices: Optional[Union[numpy.ndarray, list, torch.Tensor, warp.types.array]] = None) None

Set the default state of the prims (positions and orientations), that will be used after each reset.

Note

The default states will be set during post-reset (e.g., calling .post_reset() or world.reset() methods)

Parameters
  • positions (Optional[Union[np.ndarray, torch.Tensor, wp.array]], optional) – positions in the world frame of the prim. shape is (M, 3). Defaults to None, which means left unchanged.

  • orientations (Optional[Union[np.ndarray, torch.Tensor, wp.array]], optional) – quaternion orientations in the world frame of the prim. quaternion is scalar-first (w, x, y, z). shape is (M, 4). Defaults to None, which means left unchanged.

  • indices (Optional[Union[np.ndarray, list, torch.Tensor, wp.array]], optional) – indices to specify which prims to manipulate. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

Example:

>>> # configure default states for all prims
>>> positions = np.zeros((num_envs, 3))
>>> positions[:, 0] = np.arange(num_envs)
>>> orientations = np.tile(np.array([1.0, 0.0, 0.0, 0.0]), (num_envs, 1))
>>> prims.set_default_state(positions=positions, orientations=orientations)
>>>
>>> # set default states during post-reset
>>> prims.post_reset()
set_effort_modes(mode: str, indices: Optional[Union[numpy.ndarray, List, torch.Tensor, warp.types.array]] = None, joint_indices: Optional[Union[numpy.ndarray, List, torch.Tensor]] = None) None

Set effort modes for articulations in the view

Parameters
  • mode (str) – effort mode to be applied to prims in the view: acceleration or force.

  • indices (Optional[Union[np.ndarray, List, torch.Tensor, wp.array]], optional) – indices to specify which prims to manipulate. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

  • joint_indices (Optional[Union[np.ndarray, List, torch.Tensor, wp.array]], optional) – joint indices to specify which joints to manipulate. Shape (K,). Where K <= num of dofs. Defaults to None (i.e: all dofs).

Example:

>>> # set the effort mode for all joints to 'force'
>>> prims.set_effort_modes("force")
>>>
>>> # set only the finger joints effort mode to 'force' for the first, middle and last of the 5 envs
>>> prims.set_effort_modes("force", indices=np.array([0, 2, 4]), joint_indices=np.array([7, 8]))
set_enabled_self_collisions(flags: Union[numpy.ndarray, torch.Tensor, warp.types.array], indices: Optional[Union[numpy.ndarray, List, torch.Tensor, warp.types.array]] = None) None

Set the enable self collisions flag (physxArticulation:enabledSelfCollisions)

Parameters
  • flags (Union[np.ndarray, torch.Tensor, wp.array]) – true to enable self collision. otherwise false. shape (M,)

  • indices (Optional[Union[np.ndarray, List, torch.Tensor, wp.array]], optional) – indices to specify which prims to manipulate. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

Example:

>>> # enable the self collisions flag for all envs
>>> prims.set_enabled_self_collisions(np.full((num_envs,), True))
>>>
>>> # enable the self collisions flag only for the first, middle and last of the 5 envs
>>> prims.set_enabled_self_collisions(np.full((3,), True), indices=np.array([0, 2, 4]))
set_fixed_tendon_properties(stiffnesses: Optional[Union[numpy.ndarray, torch.Tensor, warp.types.array]] = None, dampings: Optional[Union[numpy.ndarray, torch.Tensor, warp.types.array]] = None, limit_stiffnesses: Optional[Union[numpy.ndarray, torch.Tensor, warp.types.array]] = None, limits: Optional[Union[numpy.ndarray, torch.Tensor, warp.types.array]] = None, rest_lengths: Optional[Union[numpy.ndarray, torch.Tensor, warp.types.array]] = None, offsets: Optional[Union[numpy.ndarray, torch.Tensor, warp.types.array]] = None, indices: Optional[Union[numpy.ndarray, List, torch.Tensor, warp.types.array]] = None) None

Set fixed tendon properties for articulations in the view

Search for Fixed Tendon in PhysX docs for more details

Parameters
  • stiffnesses (Union[np.ndarray, torch.Tensor, wp.array]) – fixed tendon stiffnesses for articulations in the view. shape (M, K).

  • dampings (Union[np.ndarray, torch.Tensor, wp.array]) – fixed tendon dampings for articulations in the view. shape (M, K).

  • limit_stiffnesses (Union[np.ndarray, torch.Tensor, wp.array]) – fixed tendon limit stiffnesses for articulations in the view. shape (M, K).

  • limits (Union[np.ndarray, torch.Tensor, wp.array]) – fixed tendon limits for articulations in the view. shape (M, K, 2).

  • rest_lengths (Union[np.ndarray, torch.Tensor, wp.array]) – fixed tendon rest lengths for articulations in the view. shape (M, K).

  • offsets (Union[np.ndarray, torch.Tensor, wp.array]) – fixed tendon offsets for articulations in the view. shape (M, K).

  • indices (Optional[Union[np.ndarray, List, torch.Tensor, wp.array]], optional) – indices to specify which prims to manipulate. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

Example:

>>> # set the limit stiffnesses and dampings
>>> # for the ShadowHand articulation that has 4 fixed tendons (prims.num_fixed_tendons)
>>> limit_stiffnesses = np.full((num_envs, prims.num_fixed_tendons), fill_value=10.0)
>>> dampings = np.full((num_envs, prims.num_fixed_tendons), fill_value=0.1)
>>> prims.set_fixed_tendon_properties(dampings=dampings, limit_stiffnesses=limit_stiffnesses)
set_friction_coefficients(values: Union[numpy.ndarray, torch.Tensor], indices: Optional[Union[numpy.ndarray, List, torch.Tensor, warp.types.array]] = None, joint_indices: Optional[Union[numpy.ndarray, List, torch.Tensor, warp.types.array]] = None) None

Set the friction coefficients for articulation joints in the view

Search for “Joint Friction Coefficient” in PhysX docs for more details.

Parameters
  • values (Union[np.ndarray, torch.Tensor, wp.array]) – friction coefficients for articulation joints in the view. shape (M, K).

  • indices (Optional[Union[np.ndarray, List, torch.Tensor, wp.array]], optional) – indices to specify which prims to manipulate. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

  • joint_indices (Optional[Union[np.ndarray, List, torch.Tensor, wp.array]], optional) – joint indices to specify which joints to manipulate. Shape (K,). Where K <= num of dofs. Defaults to None (i.e: all dofs).

Example:

>>> # set all joint friction coefficients to 0.05 for all envs
>>> prims.set_friction_coefficients(np.full((num_envs, prims.num_dof), 0.05))
>>>
>>> # set only the finger joint (panda_finger_joint1 (7) and panda_finger_joint2 (8)) friction coefficients
>>> # for the first, middle and last of the 5 envs to 0.05
>>> prims.set_friction_coefficients(np.full((3, 2), 0.05), indices=np.array([0,2,4]), joint_indices=np.array([7,8]))
set_gains(kps: Optional[Union[numpy.ndarray, torch.Tensor, warp.types.array]] = None, kds: Optional[Union[numpy.ndarray, torch.Tensor, warp.types.array]] = None, indices: Optional[Union[numpy.ndarray, List, torch.Tensor, warp.types.array]] = None, joint_indices: Optional[Union[numpy.ndarray, List, torch.Tensor, warp.types.array]] = None, save_to_usd: bool = False) None

Set the implicit Proportional-Derivative (PD) controller’s Kps (stiffnesses) and Kds (dampings) of articulations in the view

Parameters
  • kps (Optional[Union[np.ndarray, torch.Tensor, wp.array]], optional) – stiffness of the drives. shape is (M, K). Defaults to None.

  • kds (Optional[Union[np.ndarray, torch.Tensor, wp.array]], optional) – damping of the drives. shape is (M, K).. Defaults to None.

  • indices (Optional[Union[np.ndarray, List, torch.Tensor, wp.array]], optional) – indices to specify which prims to manipulate. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

  • joint_indices (Optional[Union[np.ndarray, List, torch.Tensor, wp.array]], optional) – joint indices to specify which joints to manipulate. Shape (K,). Where K <= num of dofs. Defaults to None (i.e: all dofs).

  • save_to_usd (bool, optional) – True to save the gains in the usd. otherwise False.

Example:

>>> # set the gains (stiffnesses and dampings) for all the articulation joints to the indicated values.
>>> # Since there are 5 envs, the gains are repeated 5 times
>>> stiffnesses = np.tile(np.array([100000, 100000, 100000, 100000, 80000, 80000, 80000, 50000, 50000]), (num_envs, 1))
>>> dampings = np.tile(np.array([8000, 8000, 8000, 8000, 5000, 5000, 5000, 2000, 2000]), (num_envs, 1))
>>> prims.set_gains(kps=stiffnesses, kds=dampings)
>>>
>>> # set the fingers gains (stiffnesses and dampings): panda_finger_joint1 (7) and panda_finger_joint2 (8)
>>> # to 50000 and 2000 respectively for the first, middle and last of the 5 envs
>>> stiffnesses = np.tile(np.array([50000, 50000]), (3, 1))
>>> dampings = np.tile(np.array([2000, 2000]), (3, 1))
>>> prims.set_gains(kps=stiffnesses, kds=dampings, indices=np.array([0, 2, 4]), joint_indices=np.array([7, 8]))
set_joint_efforts(efforts: Optional[Union[numpy.ndarray, torch.Tensor, warp.types.array]], indices: Optional[Union[numpy.ndarray, List, torch.Tensor, warp.types.array]] = None, joint_indices: Optional[Union[numpy.ndarray, List, torch.Tensor, warp.types.array]] = None) None

Set the joint efforts of articulations in the view

Note

This method can be used for effort control. For this purpose, there must be no joint drive or the stiffness and damping must be set to zero.

Parameters
  • efforts (Optional[Union[np.ndarray, torch.Tensor, wp.array]]) – efforts of articulations in the view to be set to in the next frame. shape is (M, K).

  • indices (Optional[Union[np.ndarray, List, torch.Tensor, wp.array]], optional) – indices to specify which prims to manipulate. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

  • joint_indices (Optional[Union[np.ndarray, List, torch.Tensor, wp.array]], optional) – joint indices to specify which joints to manipulate. Shape (K,). Where K <= num of dofs. Defaults to None (i.e: all dofs).

Hint

This method belongs to the methods used to set the articulation kinematic states:

set_velocities (set_linear_velocities, set_angular_velocities), set_joint_positions, set_joint_velocities, set_joint_efforts

Example:

>>> # set the efforts for all the articulation joints to the indicated values.
>>> # Since there are 5 envs, the joint efforts are repeated 5 times
>>> efforts = np.tile(np.array([10, 20, 30, 40, 50, 60, 70, 80, 90]), (num_envs, 1))
>>> prims.set_joint_efforts(efforts)
>>>
>>> # set the fingers efforts: panda_finger_joint1 (7) and panda_finger_joint2 (8) to 10
>>> # for the first, middle and last of the 5 envs
>>> efforts = np.tile(np.array([10, 10]), (3, 1))
>>> prims.set_joint_efforts(efforts, indices=np.array([0, 2, 4]), joint_indices=np.array([7, 8]))
set_joint_position_targets(positions: Optional[Union[numpy.ndarray, torch.Tensor, warp.types.array]], indices: Optional[Union[numpy.ndarray, List, torch.Tensor, warp.types.array]] = None, joint_indices: Optional[Union[numpy.ndarray, List, torch.Tensor, warp.types.array]] = None) None

Set the joint position targets for the implicit Proportional-Derivative (PD) controllers

Note

This is an independent method for controlling joints. To apply multiple targets (position, velocity, and/or effort) in the same call, consider using the apply_action method

Parameters
  • positions (Optional[Union[np.ndarray, torch.Tensor, wp.array]]) – joint position targets for the implicit PD controller. shape is (M, K).

  • indices (Optional[Union[np.ndarray, List, torch.Tensor, wp.array]], optional) – indices to specify which prims to manipulate. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

  • joint_indices (Optional[Union[np.ndarray, List, torch.Tensor, wp.array]], optional) – joint indices to specify which joints to manipulate. Shape (K,). Where K <= num of dofs. Defaults to None (i.e: all dofs).

Hint

High stiffness makes the joints snap faster and harder to the desired target, and higher damping smoothes but also slows down the joint’s movement to target

  • For position control, set relatively high stiffness and low damping (to reduce vibrations)

Example:

>>> # apply the target positions (to move all the robot joints) to the indicated values.
>>> # Since there are 5 envs, the joint positions are repeated 5 times
>>> positions = np.tile(np.array([0.0, -1.0, 0.0, -2.2, 0.0, 2.4, 0.8, 0.04, 0.04]), (num_envs, 1))
>>> prims.set_joint_position_targets(positions)
>>>
>>> # close the robot fingers: panda_finger_joint1 (7) and panda_finger_joint2 (8) to 0.0
>>> # for the first, middle and last of the 5 envs
>>> positions = np.tile(np.array([0.0, 0.0]), (3, 1))
>>> prims.set_joint_position_targets(positions, indices=np.array([0, 2, 4]), joint_indices=np.array([7, 8]))
set_joint_positions(positions: Optional[Union[numpy.ndarray, torch.Tensor, warp.types.array]], indices: Optional[Union[numpy.ndarray, List, torch.Tensor, warp.types.array]] = None, joint_indices: Optional[Union[numpy.ndarray, List, torch.Tensor, warp.types.array]] = None) None

Set the joint positions of articulations in the view

Warning

This method will immediately set (teleport) the affected joints to the indicated value. Use the set_joint_position_targets or the apply_action methods to control the articulation joints.

Parameters
  • positions (Optional[Union[np.ndarray, torch.Tensor, wp.array]]) – joint positions of articulations in the view to be set to in the next frame. shape is (M, K).

  • indices (Optional[Union[np.ndarray, List, torch.Tensor, wp.array]], optional) – indices to specify which prims to manipulate. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

  • joint_indices (Optional[Union[np.ndarray, List, torch.Tensor, wp.array]], optional) – joint indices to specify which joints to manipulate. Shape (K,). Where K <= num of dofs. Defaults to None (i.e: all dofs).

Hint

This method belongs to the methods used to set the articulation kinematic states:

set_velocities (set_linear_velocities, set_angular_velocities), set_joint_positions, set_joint_velocities, set_joint_efforts

Example:

>>> # set all the articulation joints.
>>> # Since there are 5 envs, the joint positions are repeated 5 times
>>> positions = np.tile(np.array([0.0, -1.0, 0.0, -2.2, 0.0, 2.4, 0.8, 0.04, 0.04]), (num_envs, 1))
>>> prims.set_joint_positions(positions)
>>>
>>> # set only the fingers in closed position: panda_finger_joint1 (7) and panda_finger_joint2 (8) to 0.0
>>> # for the first, middle and last of the 5 envs
>>> positions = np.tile(np.array([0.0, 0.0]), (3, 1))
>>> prims.set_joint_positions(positions, indices=np.array([0, 2, 4]), joint_indices=np.array([7, 8]))
set_joint_velocities(velocities: Optional[Union[numpy.ndarray, torch.Tensor, warp.types.array]], indices: Optional[Union[numpy.ndarray, List, torch.Tensor, warp.types.array]] = None, joint_indices: Optional[Union[numpy.ndarray, List, torch.Tensor, warp.types.array]] = None) None

Set the joint velocities of articulations in the view

Warning

This method will immediately set the affected joints to the indicated value. Use the set_joint_velocity_targets or the apply_action methods to control the articulation joints.

Parameters
  • velocities (Optional[Union[np.ndarray, torch.Tensor, wp.array]]) – joint velocities of articulations in the view to be set to in the next frame. shape is (M, K).

  • indices (Optional[Union[np.ndarray, List, torch.Tensor, wp.array]], optional) – indices to specify which prims to manipulate. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

  • joint_indices (Optional[Union[np.ndarray, List, torch.Tensor, wp.array]], optional) – joint indices to specify which joints to manipulate. Shape (K,). Where K <= num of dofs. Defaults to None (i.e: all dofs).

Hint

This method belongs to the methods used to set the articulation kinematic states:

set_velocities (set_linear_velocities, set_angular_velocities), set_joint_positions, set_joint_velocities, set_joint_efforts

Example:

>>> # set the velocities for all the articulation joints to the indicated values.
>>> # Since there are 5 envs, the joint velocities are repeated 5 times
>>> velocities = np.tile(np.array([0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, 0.9]), (num_envs, 1))
>>> prims.set_joint_velocities(velocities)
>>>
>>> # set the fingers velocities: panda_finger_joint1 (7) and panda_finger_joint2 (8) to -0.1
>>> # for the first, middle and last of the 5 envs
>>> velocities = np.tile(np.array([-0.1, -0.1]), (3, 1))
>>> prims.set_joint_velocities(velocities, indices=np.array([0, 2, 4]), joint_indices=np.array([7, 8]))
set_joint_velocity_targets(velocities: Optional[Union[numpy.ndarray, torch.Tensor, warp.types.array]], indices: Optional[Union[numpy.ndarray, List, torch.Tensor, warp.types.array]] = None, joint_indices: Optional[Union[numpy.ndarray, List, torch.Tensor, warp.types.array]] = None) None

Set the joint velocity targets for the implicit Proportional-Derivative (PD) controllers

Note

This is an independent method for controlling joints. To apply multiple targets (position, velocity, and/or effort) in the same call, consider using the apply_action method

Parameters
  • velocities (Optional[Union[np.ndarray, torch.Tensor, wp.array]]) – joint velocity targets for the implicit PD controller. shape is (M, K).

  • indices (Optional[Union[np.ndarray, List, torch.Tensor, wp.array]], optional) – indices to specify which prims to manipulate. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

  • joint_indices (Optional[Union[np.ndarray, List, torch.Tensor, wp.array]], optional) – joint indices to specify which joints to manipulate. Shape (K,). Where K <= num of dofs. Defaults to None (i.e: all dofs).

Hint

High stiffness makes the joints snap faster and harder to the desired target, and higher damping smoothes but also slows down the joint’s movement to target

  • For velocity control, stiffness must be set to zero with a non-zero damping

Example:

>>> # apply the target velocities for all the articulation joints to the indicated values.
>>> # Since there are 5 envs, the joint velocities are repeated 5 times
>>> velocities = np.tile(np.array([0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, 0.9]), (num_envs, 1))
>>> prims.set_joint_velocity_targets(velocities)
>>>
>>> # apply the fingers target velocities: panda_finger_joint1 (7) and panda_finger_joint2 (8) to -1.0
>>> # for the first, middle and last of the 5 envs
>>> velocities = np.tile(np.array([-0.1, -0.1]), (3, 1))
>>> prims.set_joint_velocity_targets(velocities, indices=np.array([0, 2, 4]), joint_indices=np.array([7, 8]))
set_joints_default_state(positions: Optional[Union[numpy.ndarray, torch.Tensor, warp.types.array]] = None, velocities: Optional[Union[numpy.ndarray, torch.Tensor, warp.types.array]] = None, efforts: Optional[Union[numpy.ndarray, torch.Tensor, warp.types.array]] = None) None

Set the joints default state (joint positions, velocities and efforts) to be applied after each reset.

Note

The default states will be set during post-reset (e.g., calling .post_reset() or world.reset() methods)

Parameters
  • positions (Optional[Union[np.ndarray, torch.Tensor, wp.array]], optional) – default joint positions. shape is (N, num of dofs). Defaults to None.

  • velocities (Optional[Union[np.ndarray, torch.Tensor, wp.array]], optional) – default joint velocities. shape is (N, num of dofs). Defaults to None.

  • efforts (Optional[Union[np.ndarray, torch.Tensor, wp.array]], optional) – default joint efforts. shape is (N, num of dofs). Defaults to None.

Example:

>>> # configure default joint states for all articulations
>>> positions = np.tile(np.array([0.0, -1.0, 0.0, -2.2, 0.0, 2.4, 0.8, 0.04, 0.04]), (num_envs, 1))
>>> prims.set_joints_default_state(
...     positions=positions,
...     velocities=np.zeros((num_envs, prims.num_dof)),
...     efforts=np.zeros((num_envs, prims.num_dof))
... )
>>>
>>> # set default states during post-reset
>>> prims.post_reset()
set_linear_velocities(velocities: Optional[Union[numpy.ndarray, torch.Tensor, warp.types.array]] = None, indices: Optional[Union[numpy.ndarray, list, torch.Tensor, warp.types.array]] = None) None

Set the linear velocities of the prims in the view

The method does this through the PhysX API only. It has to be called after initialization. Note: This method is not supported for the gpu pipeline. set_velocities method should be used instead.

Warning

This method will immediately set the articulation state

Parameters
  • velocities (Optional[Union[np.ndarray, torch.Tensor, wp.array]]) – linear velocities to set the rigid prims to. shape is (M, 3).

  • indices (Optional[Union[np.ndarray, list, torch.Tensor, wp.array]], optional) – indices to specify which prims to manipulate. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

Hint

This method belongs to the methods used to set the articulation kinematic state:

set_velocities (set_linear_velocities, set_angular_velocities), set_joint_positions, set_joint_velocities, set_joint_efforts

Example:

>>> # set each articulation linear velocity to (1.0, 1.0, 1.0)
>>> velocities = np.ones((num_envs, 3))
>>> prims.set_linear_velocities(velocities)
>>>
>>> # set only the articulation linear velocities for the first, middle and last of the 5 envs
>>> velocities = np.ones((3, 3))
>>> prims.set_linear_velocities(velocities, indices=np.array([0, 2, 4]))
set_local_poses(translations: Optional[Union[numpy.ndarray, torch.Tensor, warp.types.array]] = None, orientations: Optional[Union[numpy.ndarray, torch.Tensor, warp.types.array]] = None, indices: Optional[Union[numpy.ndarray, list, torch.Tensor, warp.types.array]] = None) None

Set prim poses in the view with respect to the local frame (the prim’s parent frame).

Warning

This method will change (teleport) the prim poses immediately to the indicated value

Parameters
  • translations (Optional[Union[np.ndarray, torch.Tensor, wp.array]], optional) – translations in the local frame of the prims (with respect to its parent prim). shape is (M, 3). Defaults to None, which means left unchanged.

  • orientations (Optional[Union[np.ndarray, torch.Tensor, wp.array]], optional) – quaternion orientations in the local frame of the prims. quaternion is scalar-first (w, x, y, z). shape is (M, 4). Defaults to None, which means left unchanged.

  • indices (Optional[Union[np.ndarray, list, torch.Tensor, wp.array]], optional) – indices to specify which prims to manipulate. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

Hint

This method belongs to the methods used to set the prim state

Example:

>>> # reposition all articulations
>>> positions = np.zeros((num_envs, 3))
>>> positions[:,0] = np.arange(num_envs)
>>> orientations = np.tile(np.array([1.0, 0.0, 0.0, 0.0]), (num_envs, 1))
>>> prims.set_local_poses(positions, orientations)
>>>
>>> # reposition only the articulations for the first, middle and last of the 5 envs
>>> positions = np.zeros((3, 3))
>>> positions[:,1] = np.arange(3)
>>> orientations = np.tile(np.array([1.0, 0.0, 0.0, 0.0]), (3, 1))
>>> prims.set_local_poses(positions, orientations, indices=np.array([0, 2, 4]))
set_local_scales(scales: Optional[Union[numpy.ndarray, torch.Tensor, warp.types.array]], indices: Optional[Union[numpy.ndarray, list, torch.Tensor, warp.types.array]] = None) None

Set prim scales in the view with respect to the local frame (the prim’s parent frame)

Parameters
  • scales (Optional[Union[np.ndarray, torch.Tensor, wp.array]]) – scales to be applied to the prim’s dimensions in the view. shape is (M, 3).

  • indices (Optional[Union[np.ndarray, list, torch.Tensor, wp.array]], optional) – indices to specify which prims to manipulate. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

Example:

>>> # set the scale for all prims. Since there are 5 envs, the scale is repeated 5 times
>>> scales = np.tile(np.array([1.0, 0.75, 0.5]), (num_envs, 1))
>>> prims.set_local_scales(scales)
>>>
>>> # set the scale for the first, middle and last of the 5 envs
>>> scales = np.tile(np.array([1.0, 0.75, 0.5]), (3, 1))
>>> prims.set_local_scales(scales, indices=np.array([0, 2, 4]))
set_max_efforts(values: Union[numpy.ndarray, torch.Tensor, warp.types.array], indices: Optional[Union[numpy.ndarray, List, torch.Tensor, warp.types.array]] = None, joint_indices: Optional[Union[numpy.ndarray, List, torch.Tensor, warp.types.array]] = None) None

Set maximum efforts for articulation in the view

Parameters
  • values (Union[np.ndarray, torch.Tensor, wp.array]) – maximum efforts for articulations in the view. shape (M, K).

  • indices (Optional[Union[np.ndarray, List, torch.Tensor, wp.array]], optional) – indices to specify which prims to manipulate. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

  • joint_indices (Optional[Union[np.ndarray, List, torch.Tensor, wp.array]], optional) – joint indices to specify which joints to manipulate. Shape (K,). Where K <= num of dofs. Defaults to None (i.e: all dofs).

Example:

>>> # set the max efforts for all the articulation joints to the indicated values.
>>> # Since there are 5 envs, the joint efforts are repeated 5 times
>>> max_efforts = np.tile(np.array([10000, 9000, 8000, 7000, 6000, 5000, 4000, 1000, 1000]), (num_envs, 1))
>>> prims.set_max_efforts(max_efforts)
>>>
>>> # set the fingers max efforts: panda_finger_joint1 (7) and panda_finger_joint2 (8) to 1000
>>> # for the first, middle and last of the 5 envs
>>> max_efforts = np.tile(np.array([1000, 1000]), (3, 1))
>>> prims.set_max_efforts(max_efforts, indices=np.array([0, 2, 4]), joint_indices=np.array([7, 8]))
set_sleep_thresholds(thresholds: Union[numpy.ndarray, torch.Tensor, warp.types.array], indices: Optional[Union[numpy.ndarray, List, torch.Tensor, warp.types.array]] = None) None

Set the threshold for articulations to enter a sleep state

Search for Articulations and Sleeping in PhysX docs for more details

Parameters
  • thresholds (Union[np.ndarray, torch.Tensor, wp.array]) – sleep thresholds to be applied. shape (M,).

  • indices (Optional[Union[np.ndarray, List, torch.Tensor, wp.array]], optional) – indices to specify which prims to manipulate. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

Example:

>>> # set the sleep threshold for all envs
>>> prims.set_sleep_thresholds(np.full((num_envs,), 0.01))
>>>
>>> # set only the sleep threshold for the first, middle and last of the 5 envs
>>> prims.set_sleep_thresholds(np.full((3,), 0.01), indices=np.array([0, 2, 4]))
set_solver_position_iteration_counts(counts: Union[numpy.ndarray, torch.Tensor, warp.types.array], indices: Optional[Union[numpy.ndarray, List, torch.Tensor, warp.types.array]] = None) None

Set the solver (position) iteration count for the articulations

The solver iteration count determines how accurately contacts, drives, and limits are resolved. Search for Solver Iteration Count in PhysX docs for more details.

Warning

Setting a higher number of iterations may improve the fidelity of the simulation, although it may affect its performance.

Parameters
  • counts (Union[np.ndarray, torch.Tensor, wp.array]) – number of iterations for the solver. Shape (M,).

  • indices (Optional[Union[np.ndarray, List, torch.Tensor, wp.array]], optional) – indices to specify which prims to manipulate. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

Example:

>>> # set the position iteration count for all envs
>>> prims.set_solver_position_iteration_counts(np.full((num_envs,), 64))
>>>
>>> # set only the position iteration count for the first, middle and last of the 5 envs
>>> prims.set_solver_position_iteration_counts(np.full((3,), 64), indices=np.array([0, 2, 4]))
set_solver_velocity_iteration_counts(counts: Union[numpy.ndarray, torch.Tensor, warp.types.array], indices: Optional[Union[numpy.ndarray, List, torch.Tensor, warp.types.array]] = None) None

Set the solver (velocity) iteration count for the articulations

The solver iteration count determines how accurately contacts, drives, and limits are resolved. Search for Solver Iteration Count in PhysX docs for more details.

Warning

Setting a higher number of iterations may improve the fidelity of the simulation, although it may affect its performance.

Parameters
  • counts (Union[np.ndarray, torch.Tensor, wp.array]) – number of iterations for the solver. Shape (M,).

  • indices (Optional[Union[np.ndarray, List, torch.Tensor, wp.array]], optional) – indices to specify which prims to manipulate. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

Example:

>>> # set the velocity iteration count for all envs
>>> prims.set_solver_velocity_iteration_counts(np.full((num_envs,), 64))
>>>
>>> # set only the velocity iteration count for the first, middle and last of the 5 envs
>>> prims.set_solver_velocity_iteration_counts(np.full((3,), 64), indices=np.array([0, 2, 4]))
set_stabilization_thresholds(thresholds: Union[numpy.ndarray, torch.Tensor, warp.types.array], indices: Optional[Union[numpy.ndarray, List, torch.Tensor, warp.types.array]] = None) None

Set the mass-normalized kinetic energy below which the articulation may participate in stabilization

Search for Stabilization Threshold in PhysX docs for more details

Parameters
  • thresholds (Union[np.ndarray, torch.Tensor, wp.array]) – stabilization thresholds to be applied. Shape (M,).

  • indices (Optional[Union[np.ndarray, List, torch.Tensor, wp.array]], optional) – indices to specify which prims to manipulate. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

Example:

>>> # set the stabilization threshold for all envs
>>> prims.set_stabilization_thresholds(np.full((num_envs,), 0.005))
>>>
>>> # set only the stabilization threshold for the first, middle and last of the 5 envs
>>> prims.set_stabilization_thresholds(np.full((3,), 0.0051), indices=np.array([0, 2, 4]))
set_velocities(velocities: Optional[Union[numpy.ndarray, torch.Tensor, warp.types.array]] = None, indices: Optional[Union[numpy.ndarray, list, torch.Tensor, warp.types.array]] = None) None

Set the linear and angular velocities of the prims in the view at once.

The method does this through the PhysX API only. It has to be called after initialization

Warning

This method will immediately set the articulation state

Parameters
  • velocities (Optional[Union[np.ndarray, torch.Tensor, wp.array]]) – linear and angular velocities respectively to set the rigid prims to. shape is (M, 6).

  • indices (Optional[Union[np.ndarray, list, torch.Tensor, wp.array]], optional) – indices to specify which prims to manipulate. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

Hint

This method belongs to the methods used to set the articulation kinematic state:

set_velocities (set_linear_velocities, set_angular_velocities), set_joint_positions, set_joint_velocities, set_joint_efforts

Example:

>>> # set each articulation linear velocity to (1., 1., 1.) and angular velocity to (.1, .1, .1)
>>> velocities = np.ones((num_envs, 6))
>>> velocities[:,3:] = 0.1
>>> prims.set_velocities(velocities)
>>>
>>> # set only the articulation velocities for the first, middle and last of the 5 envs
>>> velocities = np.ones((3, 6))
>>> velocities[:,3:] = 0.1
>>> prims.set_velocities(velocities, indices=np.array([0, 2, 4]))
set_visibilities(visibilities: Union[numpy.ndarray, torch.Tensor, warp.types.array], indices: Optional[Union[numpy.ndarray, list, torch.Tensor, warp.types.array]] = None) None

Set the visibilities of the prims in stage

Parameters
  • visibilities (Union[np.ndarray, torch.Tensor, wp.array]) – flag to set the visibilities of the usd prims in stage. Shape (M,). Where M <= size of the encapsulated prims in the view.

  • indices (Optional[Union[np.ndarray, list, torch.Tensor, wp.array]], optional) – indices to specify which prims to manipulate. Shape (M,). Defaults to None (i.e: all prims in the view).

Example:

>>> # make all prims not visible in the stage
>>> prims.set_visibilities(visibilities=[False] * num_envs)
set_world_poses(positions: Optional[Union[numpy.ndarray, torch.Tensor, warp.types.array]] = None, orientations: Optional[Union[numpy.ndarray, torch.Tensor, warp.types.array]] = None, indices: Optional[Union[numpy.ndarray, list, torch.Tensor, warp.types.array]] = None) None

Set poses of prims in the view with respect to the world’s frame.

Warning

This method will change (teleport) the prim poses immediately to the indicated value

Parameters
  • positions (Optional[Union[np.ndarray, torch.Tensor, wp.array]], optional) – positions in the world frame of the prim. shape is (M, 3). Defaults to None, which means left unchanged.

  • orientations (Optional[Union[np.ndarray, torch.Tensor, wp.array]], optional) – quaternion orientations in the world frame of the prims. quaternion is scalar-first (w, x, y, z). shape is (M, 4). Defaults to None, which means left unchanged.

  • indices (Optional[Union[np.ndarray, list, torch.Tensor, wp.array]], optional) – indices to specify which prims to manipulate. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

Hint

This method belongs to the methods used to set the prim state

Example:

>>> # reposition all articulations in row (x-axis)
>>> positions = np.zeros((num_envs, 3))
>>> positions[:,0] = np.arange(num_envs)
>>> orientations = np.tile(np.array([1.0, 0.0, 0.0, 0.0]), (num_envs, 1))
>>> prims.set_world_poses(positions, orientations)
>>>
>>> # reposition only the articulations for the first, middle and last of the 5 envs in column (y-axis)
>>> positions = np.zeros((3, 3))
>>> positions[:,1] = np.arange(3)
>>> orientations = np.tile(np.array([1.0, 0.0, 0.0, 0.0]), (3, 1))
>>> prims.set_world_poses(positions, orientations, indices=np.array([0, 2, 4]))
switch_control_mode(mode: str, indices: Optional[Union[numpy.ndarray, List, torch.Tensor, warp.types.array]] = None, joint_indices: Optional[Union[numpy.ndarray, List, torch.Tensor, warp.types.array]] = None) None

Switch control mode between "position", "velocity", or "effort" for all joints

This method will set the implicit Proportional-Derivative (PD) controller’s Kps (stiffnesses) and Kds (dampings), defined via the set_gains method, of the selected articulations and joints according to the following rule:

Control mode

Stiffnesses

Dampings

"position"

Kps

Kds

"velocity"

0

Kds

"effort"

0

0

Parameters
  • mode (str) – control mode to switch the articulations specified to. It can be "position", "velocity", or "effort"

  • indices (Optional[Union[np.ndarray, List, torch.Tensor, wp.array]], optional) – indices to specify which prims to manipulate. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

  • joint_indices (Optional[Union[np.ndarray, List, torch.Tensor, wp.array]], optional) – joint indices to specify which joints to manipulate. Shape (K,). Where K <= num of dofs. Defaults to None (i.e: all dofs).

Example:

>>> # set 'velocity' as control mode for all joints
>>> prims.switch_control_mode("velocity")
>>>
>>> # set 'effort' as control mode only for the fingers: panda_finger_joint1 (7) and panda_finger_joint2 (8)
>>> # for the first, middle and last of the 5 envs
>>> prims.switch_control_mode("effort", indices=np.array([0, 2, 4]), joint_indices=np.array([7, 8]))
switch_dof_control_mode(mode: str, dof_index: int, indices: Optional[Union[numpy.ndarray, List, torch.Tensor, warp.types.array]] = None) None

Switch control mode between "position", "velocity", or "effort" for the specified DOF

This method will set the implicit Proportional-Derivative (PD) controller’s Kps (stiffnesses) and Kds (dampings), defined via the set_gains method, of the selected DOF according to the following rule:

Control mode

Stiffnesses

Dampings

"position"

Kps

Kds

"velocity"

0

Kds

"effort"

0

0

Parameters
  • mode (str) – control mode to switch the DOF specified to. It can be "position", "velocity" or "effort"

  • dof_index (int) – dof index to switch the control mode of.

  • indices (Optional[Union[np.ndarray, List, torch.Tensor, wp.array]], optional) – indices to specify which prims to manipulate. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

Example:

>>> # set 'velocity' as control mode for the panda_joint1 (0) joint for all envs
>>> prims.switch_dof_control_mode("velocity", dof_index=0)
>>>
>>> # set 'effort' as control mode for the panda_joint1 (0) for the first, middle and last of the 5 envs
>>> prims.switch_dof_control_mode("effort", dof_index=0, indices=np.array([0, 2, 4]))

ArticulationController

class ArticulationController

PD Controller of all degrees of freedom of an articulation, can apply position targets, velocity targets and efforts.

Checkout the required tutorials at

https://docs.omniverse.nvidia.com/app_isaacsim/app_isaacsim/overview.html

apply_action(control_actions: omni.isaac.core.utils.types.ArticulationAction) None

[summary]

Parameters
  • control_actions (ArticulationAction) – actions to be applied for next physics step.

  • indices (Optional[Union[list, np.ndarray]], optional) – degree of freedom indices to apply actions to. Defaults to all degrees of freedom.

Raises

Exception – [description]

get_applied_action() omni.isaac.core.utils.types.ArticulationAction
Raises

Exception – [description]

Returns

Gets last applied action.

Return type

ArticulationAction

get_effort_modes() List[str]

[summary]

Raises
  • Exception – [description]

  • NotImplementedError – [description]

Returns

[description]

Return type

np.ndarray

get_gains() Tuple[numpy.ndarray, numpy.ndarray]

[summary]

Raises

Exception – [description]

Returns

[description]

Return type

Tuple[np.ndarray, np.ndarray]

get_joint_limits() Tuple[numpy.ndarray, numpy.ndarray]

[summary]

Raises

Exception – [description]

Returns

[description]

Return type

Tuple[np.ndarray, np.ndarray]

get_max_efforts() numpy.ndarray

[summary]

Raises

Exception – [description]

Returns

[description]

Return type

np.ndarray

initialize(handle, articulation_view) None

[summary]

Parameters
  • handle ([type]) – [description]

  • dof_infos ([type]) – [description]

set_effort_modes(mode: str, joint_indices: Optional[Union[numpy.ndarray, list]] = None) None

[summary]

Parameters
  • mode (str) – [description]

  • indices (Optional[Union[np.ndarray, list]], optional) – [description]. Defaults to None.

Raises
  • Exception – [description]

  • Exception – [description]

set_gains(kps: Optional[numpy.ndarray] = None, kds: Optional[numpy.ndarray] = None, save_to_usd: bool = False) None

[summary]

Parameters
  • kps (Optional[np.ndarray], optional) – [description]. Defaults to None.

  • kds (Optional[np.ndarray], optional) – [description]. Defaults to None.

Raises

Exception – [description]

set_max_efforts(values: numpy.ndarray, joint_indices: Optional[Union[numpy.ndarray, list]] = None) None

[summary]

Parameters
  • value (float, optional) – [description]. Defaults to None.

  • indices (Optional[Union[np.ndarray, list]], optional) – [description]. Defaults to None.

Raises

Exception – [description]

switch_control_mode(mode: str) None

[summary]

Parameters

mode (str) – [description]

Raises

Exception – [description]

switch_dof_control_mode(dof_index: int, mode: str) None

[summary]

Parameters
  • dof_index (int) – [description]

  • mode (str) – [description]

Raises

Exception – [description]

Loggers

DataLogger

class DataLogger

This class takes care of collecting data as well as reading already saved data in order to replay it for instance.

add_data(data: dict, current_time_step: float, current_time: float) None

Adds data to the log

Parameters
  • data (dict) – Dictionary representing the data to be logged at this time index.

  • current_time_step (float) – time step corresponding to the data collected.

  • current_time (float) – time in seconds corresponding to the data collected.

add_data_frame_logging_func(func: Callable[[List[omni.isaac.core.tasks.base_task.BaseTask], omni.isaac.core.scenes.scene.Scene], Dict]) None
Parameters

func (Callable[[list[BaseTask], Scene], None]) –

function to be called at every step when the logger is started. should follow:

def dummy_data_collection_fn(tasks, scene):

return {“data 1”: [data]}

get_data_frame(data_frame_index: int) omni.isaac.core.utils.types.DataFrame
Parameters

data_frame_index (int) – index of the data frame to retrieve.

Returns

Data Frame collected/ retrieved at the specified data frame index.

Return type

DataFrame

get_num_of_data_frames() int
Returns

the number of data frames collected/ retrieved in the data logger.

Return type

int

is_started() bool
Returns

True if data collection is started/ resumed. False otherwise.

Return type

bool

load(log_path: str) None

Loads data from a json file to read back a previous saved data or to resume recording data from another time step.

Parameters

log_path (str) – path of the json file to be used to load the data.

pause() None

Pauses data collection.

reset() None

Clears the data in the logger.

save(log_path: str) None

Saves the current data in the logger to a json file

Parameters

log_path (str) – path of the json file to be used to save the data.

start() None

Resumes/ starts data collection.

Materials

Visual Material

class VisualMaterial(name: str, prim_path: str, prim: pxr.Usd.Prim, shaders_list: List[pxr.UsdShade.Shader], material: pxr.UsdShade.Material)

[summary]

Parameters
  • name (str) – [description]

  • prim_path (str) – [description]

  • prim (Usd.Prim) – [description]

  • shaders_list (list[UsdShade.Shader]) – [description]

  • material (UsdShade.Material) – [description]

property material: pxr.UsdShade.Material

[summary]

Returns

[description]

Return type

UsdShade.Material

property name: str

[summary]

Returns

[description]

Return type

str

property prim: pxr.Usd.Prim

[summary]

Returns

[description]

Return type

Usd.Prim

property prim_path: str

[summary]

Returns

[description]

Return type

str

property shaders_list: List[pxr.UsdShade.Shader]

[summary]

Returns

[description]

Return type

[type]

Preview Surface

class PreviewSurface(prim_path: str, name: str = 'preview_surface', shader: Optional[pxr.UsdShade.Shader] = None, color: Optional[numpy.ndarray] = None, roughness: Optional[float] = None, metallic: Optional[float] = None)

[summary]

Parameters
  • prim_path (str) – [description]

  • name (str, optional) – [description]. Defaults to “preview_surface”.

  • shader (Optional[UsdShade.Shader], optional) – [description]. Defaults to None.

  • color (Optional[np.ndarray], optional) – [description]. Defaults to None.

  • roughness (Optional[float], optional) – [description]. Defaults to None.

  • metallic (Optional[float], optional) – [description]. Defaults to None.

get_color() numpy.ndarray

[summary]

Returns

[description]

Return type

np.ndarray

get_metallic() float

[summary]

Returns

[description]

Return type

float

get_roughness() float

[summary]

Returns

[description]

Return type

float

property material: pxr.UsdShade.Material

[summary]

Returns

[description]

Return type

UsdShade.Material

property name: str

[summary]

Returns

[description]

Return type

str

property prim: pxr.Usd.Prim

[summary]

Returns

[description]

Return type

Usd.Prim

property prim_path: str

[summary]

Returns

[description]

Return type

str

set_color(color: numpy.ndarray) None

[summary]

Parameters

color (np.ndarray) – [description]

set_metallic(metallic: float) None

[summary]

Parameters

metallic (float) – [description]

set_roughness(roughness: float) None

[summary]

Parameters

roughness (float) – [description]

property shaders_list: List[pxr.UsdShade.Shader]

[summary]

Returns

[description]

Return type

[type]

OmniPBR Material

class OmniPBR(prim_path: str, name: str = 'omni_pbr', shader: Optional[pxr.UsdShade.Shader] = None, texture_path: Optional[str] = None, texture_scale: Optional[numpy.ndarray] = None, texture_translate: Optional[numpy.ndarray] = None, color: Optional[numpy.ndarray] = None)

[summary]

Parameters
  • prim_path (str) – [description]

  • name (str, optional) – [description]. Defaults to “omni_pbr”.

  • shader (Optional[UsdShade.Shader], optional) – [description]. Defaults to None.

  • texture_path (Optional[str], optional) – [description]. Defaults to None.

  • texture_scale (Optional[np.ndarray], optional) – [description]. Defaults to None.

  • texture_translate (Optional[np.ndarray, optional) – [description]. Defaults to None.

  • color (Optional[np.ndarray], optional) – [description]. Defaults to None.

get_color() numpy.ndarray

[summary]

Returns

[description]

Return type

np.ndarray

get_metallic_constant() float

[summary]

Returns

[description]

Return type

float

get_project_uvw() bool

[summary]

Returns

[description]

Return type

bool

get_reflection_roughness() float

[summary]

Returns

[description]

Return type

float

get_texture() str

[summary]

Returns

[description]

Return type

str

get_texture_scale() numpy.ndarray

[summary]

Returns

[description]

Return type

np.ndarray

get_texture_translate() numpy.ndarray

[summary]

Returns

[description]

Return type

np.ndarray

property material: pxr.UsdShade.Material

[summary]

Returns

[description]

Return type

UsdShade.Material

property name: str

[summary]

Returns

[description]

Return type

str

property prim: pxr.Usd.Prim

[summary]

Returns

[description]

Return type

Usd.Prim

property prim_path: str

[summary]

Returns

[description]

Return type

str

set_color(color: numpy.ndarray) None

[summary]

Parameters

color (np.ndarray) – [description]

set_metallic_constant(amount: float) None

[summary]

Parameters

amount (float) – [description]

set_project_uvw(flag: bool) None

[summary]

Parameters

flag (bool) – [description]

set_reflection_roughness(amount: float) None

[summary]

Parameters

amount (float) – [description]

set_texture(path: str) None

[summary]

Parameters

path (str) – [description]

set_texture_scale(x: float, y: float) None

[summary]

Parameters
  • x (float) – [description]

  • y (float) – [description]

set_texture_translate(x: float, y: float) None

[summary]

Parameters
  • x (float) – [description]

  • y (float) – [description]

property shaders_list: List[pxr.UsdShade.Shader]

[summary]

Returns

[description]

Return type

[type]

Omni Glass Material

class OmniGlass(prim_path: str, name: str = 'omni_glass', shader: Optional[pxr.UsdShade.Shader] = None, color: Optional[numpy.ndarray] = None, ior: Optional[float] = None, depth: Optional[float] = None, thin_walled: Optional[bool] = None)

[summary]

Parameters
  • prim_path (str) – [description]

  • name (str, optional) – [description]. Defaults to “omni_glass”.

  • shader (Optional[UsdShade.Shader], optional) – [description]. Defaults to None.

  • color (Optional[np.ndarray], optional) – [description]. Defaults to None.

  • ior (Optional[float], optional) – [description]. Defaults to None.

  • depth (Optional[float], optional) – [description]. Defaults to None.

  • thin_walled (Optional[bool], optional) – [description]. Defaults to None.

Raises

Exception – [description]

get_color() Optional[numpy.ndarray]

[summary]

Returns

[description]

Return type

np.ndarray

get_depth() Optional[float]
get_ior() Optional[float]
get_thin_walled() Optional[float]
property material: pxr.UsdShade.Material

[summary]

Returns

[description]

Return type

UsdShade.Material

property name: str

[summary]

Returns

[description]

Return type

str

property prim: pxr.Usd.Prim

[summary]

Returns

[description]

Return type

Usd.Prim

property prim_path: str

[summary]

Returns

[description]

Return type

str

set_color(color: numpy.ndarray) None

[summary]

Parameters

color (np.ndarray) – [description]

set_depth(depth: float) None
set_ior(ior: float) None
set_thin_walled(thin_walled: float) None
property shaders_list: List[pxr.UsdShade.Shader]

[summary]

Returns

[description]

Return type

[type]

Physics Material

class PhysicsMaterial(prim_path: str, name: str = 'physics_material', static_friction: Optional[float] = None, dynamic_friction: Optional[float] = None, restitution: Optional[float] = None)

[summary]

Parameters
  • prim_path (str) – [description]

  • name (str, optional) – [description]. Defaults to “physics_material”.

  • static_friction (Optional[float], optional) – [description]. Defaults to None.

  • dynamic_friction (Optional[float], optional) – [description]. Defaults to None.

  • restitution (Optional[float], optional) – [description]. Defaults to None.

get_dynamic_friction() float

[summary]

Returns

[description]

Return type

float

get_restitution() float

[summary]

Returns

[description]

Return type

float

get_static_friction() float

[summary]

Returns

[description]

Return type

float

property material: pxr.UsdShade.Material

[summary]

Returns

[description]

Return type

UsdShade.Material

property name: str

[summary]

Returns

[description]

Return type

str

property prim: pxr.Usd.Prim

[summary]

Returns

[description]

Return type

Usd.Prim

property prim_path: str

[summary]

Returns

[description]

Return type

str

set_dynamic_friction(friction: float) None

[summary]

Parameters

friction (float) – [description]

set_restitution(restitution: float) None

[summary]

Parameters

restitution (float) – [description]

set_static_friction(friction: float) None

[summary]

Parameters

friction (float) – [description]

Particle Material

class ParticleMaterial(prim_path: str, name: Optional[str] = 'particle_material', friction: Optional[float] = None, particle_friction_scale: Optional[float] = None, damping: Optional[float] = None, viscosity: Optional[float] = None, vorticity_confinement: Optional[float] = None, surface_tension: Optional[float] = None, cohesion: Optional[float] = None, adhesion: Optional[float] = None, particle_adhesion_scale: Optional[float] = None, adhesion_offset_scale: Optional[float] = None, gravity_scale: Optional[float] = None, lift: Optional[float] = None, drag: Optional[float] = None)

A wrapper around position-based-dynamics (PBD) material for particles used to simulate fluids, cloth and inflatables.

Note

Currently, only a single material per particle system is supported which applies to all objects that are associated with the system.

get_adhesion() float
Returns

The adhesion for interaction between particles (solid or fluid), and rigids or deformables.

Return type

float

get_adhesion_offset_scale() float
Returns

The adhesion offset scale.

Return type

float

get_cohesion() float
Returns

The cohesion for interaction between fluid particles.

Return type

float

get_damping() float
Returns

The global velocity damping coefficient.

Return type

float

get_drag() float
Returns

The drag coefficient, basic aerodynamic drag model coefficient.

Return type

float

get_friction() float
Returns

The friction coefficient.

Return type

float

get_gravity_scale() float
Returns

The gravitational acceleration scaling factor.

Return type

float

get_lift() float
Returns

The lift coefficient, basic aerodynamic lift model coefficient.

Return type

float

get_particle_adhesion_scale() float
Returns

The particle adhesion scale.

Return type

float

get_particle_friction_scale() float
Returns

The particle friction scale.

Return type

float

get_surface_tension() float
Returns

The surface tension for fluid particles.

Return type

float

get_viscosity() float
Returns

The viscosity.

Return type

float

get_vorticity_confinement() float
Returns

The vorticity confinement for fluid particles.

Return type

float

initialize(physics_sim_view=None) None
is_valid() bool
Returns

True is the current prim path corresponds to a valid prim in stage. False otherwise.

Return type

bool

property material: pxr.UsdShade.Material

Returns: UsdShade.Material: The USD Material object.

property name: Optional[str]

Returns: str: name given to the prim when instantiating it. Otherwise None.

post_reset() None

Resets the prim to its default state.

property prim: pxr.Usd.Prim

Returns: Usd.Prim: The USD prim present.

property prim_path: str

Returns: str: The stage path to the material.

set_adhesion(value: float) None

Sets the adhesion for interaction between particles (solid or fluid), and rigid or deformable objects.

Note

Adhesion also applies to solid-solid particle interactions, but is multiplied with the particle adhesion scale.

Parameters

value (float) – The adhesion. Range: [0, inf), Units: dimensionless

set_adhesion_offset_scale(value: float) None

Sets the adhesion offset scale.

It defines the offset at which adhesion ceases to take effect. For interactions between particles (fluid or solid), and rigids or deformables, the adhesion offset is defined relative to the rest offset. For solid particle-particle interactions, the adhesion offset is defined relative to the solid rest offset.

Parameters

value (float) – The adhesion offset scale. Range: [0, inf), Units: dimensionless

set_cohesion(value: float) None

Sets the cohesion for interaction between fluid particles.

Parameters

value (float) – The cohesion. Range: [0, inf), Units: dimensionless

set_damping(value: float) None

Sets the global velocity damping coefficient.

Parameters

value (float) – The damping coefficient. Range: [0, inf), Units: dimensionless

set_drag(value: float) None

Sets the drag coefficient, i.e. basic aerodynamic drag model coefficient.

It is useful for cloth and inflatable particle objects.

Parameters

value (float) – The drag coefficient. Range: [0, inf), Units: dimensionless

set_friction(value: float) None

Sets the friction coefficient.

The friction takes effect in all interactions between particles and rigids or deformables. For solid particle-particle interactions it is multiplied by the particle friction scale.

Parameters

value (float) – The friction coefficient. Range: [0, inf), Units: dimensionless

set_gravity_scale(value: float) None

Sets the gravitational acceleration scaling factor.

It can be used to approximate lighter-than-air inflatable. For example (-1.0 would invert gravity).

Parameters

value (float) – The gravity scale. Range: (-inf , inf), Units: dimensionless

set_lift(value: float) None

Sets the lift coefficient, i.e. basic aerodynamic lift model coefficient.

It is useful for cloth and inflatable particle objects.

Parameters

value (float) – The lift coefficient. Range: [0, inf), Units: dimensionless

set_particle_adhesion_scale(value: float) None

Sets the particle adhesion scale.

This coefficient scales the adhesion for solid particle-particle interaction.

Parameters

value (float) – The adhesion scale. Range: [0, inf), Units: dimensionless

set_particle_friction_scale(value: float) None

Sets the particle friction scale.

The coefficient that scales friction for solid particle-particle interaction.

Parameters

value (float) – The particle friction scale. Range: [0, inf), Units: dimensionless

set_surface_tension(value: float) None

Sets the surface tension for fluid particles.

Parameters

value (float) – The surface tension. Range: [0, inf), Units: 1 / (distance * distance * distance)

set_viscosity(value: float) None

Sets the viscosity for fluid particles.

Parameters

value (float) – The viscosity. Range: [0, inf), Units: dimensionless

set_vorticity_confinement(value: float) None

Sets the vorticity confinement for fluid particles.

This helps prevent energy loss due to numerical solver by adding vortex-like accelerations to the particles.

Parameters

value (float) – The vorticity confinement. Range: [0, inf), Units: dimensionless

Particle Material View

class ParticleMaterialView(prim_paths_expr: str, name: str = 'particle_material_view', frictions: Optional[Union[numpy.ndarray, torch.Tensor]] = None, particle_friction_scales: Optional[Union[numpy.ndarray, torch.Tensor]] = None, dampings: Optional[Union[numpy.ndarray, torch.Tensor]] = None, viscosities: Optional[Union[numpy.ndarray, torch.Tensor]] = None, vorticity_confinements: Optional[Union[numpy.ndarray, torch.Tensor]] = None, surface_tensions: Optional[Union[numpy.ndarray, torch.Tensor]] = None, cohesions: Optional[Union[numpy.ndarray, torch.Tensor]] = None, adhesions: Optional[Union[numpy.ndarray, torch.Tensor]] = None, particle_adhesion_scales: Optional[Union[numpy.ndarray, torch.Tensor]] = None, adhesion_offset_scales: Optional[Union[numpy.ndarray, torch.Tensor]] = None, gravity_scales: Optional[Union[numpy.ndarray, torch.Tensor]] = None, lifts: Optional[Union[numpy.ndarray, torch.Tensor]] = None, drags: Optional[Union[numpy.ndarray, torch.Tensor]] = None)

The view class to deal with particleMaterial prims. Provides high level functions to deal with particle material (1 or more particle materials) as well as its attributes/ properties. This object wraps all matching materials found at the regex provided at the prim_paths_expr. This object wraps all matching materials Prims found at the regex provided at the prim_paths_expr.

property count: int

Returns: int: number of rigid shapes for the prims in the view.

get_adhesion_offset_scales(indices: Optional[Union[numpy.ndarray, list, torch.Tensor]] = None, clone: bool = True) Union[numpy.ndarray, torch.Tensor]

Gets the adhesion offset scale of materials indicated by the indices.

Parameters
  • indices (Optional[Union[np.ndarray, list, torch.Tensor]], optional) – indices to specify which material prims to query. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

  • clone (bool, optional) – True to return a clone of the internal buffer. Otherwise False. Defaults to True.

Returns

adhesion offset scale tensor with shape (M, )

Return type

Union[np.ndarray, torch.Tensor]

get_adhesions(indices: Optional[Union[numpy.ndarray, list, torch.Tensor]] = None, clone: bool = True) Union[numpy.ndarray, torch.Tensor]

Gets the adhesion of materials indicated by the indices.

Parameters
  • indices (Optional[Union[np.ndarray, list, torch.Tensor]], optional) – indices to specify which material prims to query. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

  • clone (bool, optional) – True to return a clone of the internal buffer. Otherwise False. Defaults to True.

Returns

adhesion tensor with shape (M, )

Return type

Union[np.ndarray, torch.Tensor]

get_cohesions(indices: Optional[Union[numpy.ndarray, list, torch.Tensor]] = None, clone: bool = True) Union[numpy.ndarray, torch.Tensor]

Gets the cohesion of materials indicated by the indices.

Parameters
  • indices (Optional[Union[np.ndarray, list, torch.Tensor]], optional) – indices to specify which material prims to query. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

  • clone (bool, optional) – True to return a clone of the internal buffer. Otherwise False. Defaults to True.

Returns

cohesion tensor with shape (M, )

Return type

Union[np.ndarray, torch.Tensor]

get_dampings(indices: Optional[Union[numpy.ndarray, list, torch.Tensor]] = None, clone: bool = True) Union[numpy.ndarray, torch.Tensor]

Gets the dampings of materials indicated by the indices.

Parameters
  • indices (Optional[Union[np.ndarray, list, torch.Tensor]], optional) – indices to specify which material prims to query. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

  • clone (bool, optional) – True to return a clone of the internal buffer. Otherwise False. Defaults to True.

Returns

dampings tensor with shape (M, )

Return type

Union[np.ndarray, torch.Tensor]

get_drags(indices: Optional[Union[numpy.ndarray, list, torch.Tensor]] = None, clone: bool = True) Union[numpy.ndarray, torch.Tensor]

Gets the drags of materials indicated by the indices.

Parameters
  • indices (Optional[Union[np.ndarray, list, torch.Tensor]], optional) – indices to specify which material prims to query. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

  • clone (bool, optional) – True to return a clone of the internal buffer. Otherwise False. Defaults to True.

Returns

drag tensor with shape (M, )

Return type

Union[np.ndarray, torch.Tensor]

get_frictions(indices: Optional[Union[numpy.ndarray, list, torch.Tensor]] = None, clone: bool = True) Union[numpy.ndarray, torch.Tensor]

Gets the friction of materials indicated by the indices.

Parameters
  • indices (Optional[Union[np.ndarray, list, torch.Tensor]], optional) – indices to specify which material prims to query. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

  • clone (bool, optional) – True to return a clone of the internal buffer. Otherwise False. Defaults to True.

Returns

friction tensor with shape (M, )

Return type

Union[np.ndarray, torch.Tensor]

get_gravity_scales(indices: Optional[Union[numpy.ndarray, list, torch.Tensor]] = None, clone: bool = True) Union[numpy.ndarray, torch.Tensor]

Gets the gravity scale of materials indicated by the indices.

Parameters
  • indices (Optional[Union[np.ndarray, list, torch.Tensor]], optional) – indices to specify which material prims to query. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

  • clone (bool, optional) – True to return a clone of the internal buffer. Otherwise False. Defaults to True.

Returns

gravity scale tensor with shape (M, )

Return type

Union[np.ndarray, torch.Tensor]

get_lifts(indices: Optional[Union[numpy.ndarray, list, torch.Tensor]] = None, clone: bool = True) Union[numpy.ndarray, torch.Tensor]

Gets the lifts of materials indicated by the indices.

Parameters
  • indices (Optional[Union[np.ndarray, list, torch.Tensor]], optional) – indices to specify which material prims to query. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

  • clone (bool, optional) – True to return a clone of the internal buffer. Otherwise False. Defaults to True.

Returns

lift tensor with shape (M, )

Return type

Union[np.ndarray, torch.Tensor]

get_particle_adhesion_scales(indices: Optional[Union[numpy.ndarray, list, torch.Tensor]] = None, clone: bool = True) Union[numpy.ndarray, torch.Tensor]

Gets the adhesion scale of materials indicated by the indices.

Parameters
  • indices (Optional[Union[np.ndarray, list, torch.Tensor]], optional) – indices to specify which material prims to query. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

  • clone (bool, optional) – True to return a clone of the internal buffer. Otherwise False. Defaults to True.

Returns

adhesion scale tensor with shape (M, )

Return type

Union[np.ndarray, torch.Tensor]

get_particle_friction_scales(indices: Optional[Union[numpy.ndarray, list, torch.Tensor]] = None, clone: bool = True) Union[numpy.ndarray, torch.Tensor]

Gets the particle friction scale of materials indicated by the indices.

Parameters
  • indices (Optional[Union[np.ndarray, list, torch.Tensor]], optional) – indices to specify which material prims to query. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

  • clone (bool, optional) – True to return a clone of the internal buffer. Otherwise False. Defaults to True.

Returns

particle friction scale tensor with shape (M, )

Return type

Union[np.ndarray, torch.Tensor]

get_surface_tensions(indices: Optional[Union[numpy.ndarray, list, torch.Tensor]] = None, clone: bool = True) Union[numpy.ndarray, torch.Tensor]

Gets the surface tension of materials indicated by the indices.

Parameters
  • indices (Optional[Union[np.ndarray, list, torch.Tensor]], optional) – indices to specify which material prims to query. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

  • clone (bool, optional) – True to return a clone of the internal buffer. Otherwise False. Defaults to True.

Returns

surface tension tensor with shape (M, )

Return type

Union[np.ndarray, torch.Tensor]

get_viscosities(indices: Optional[Union[numpy.ndarray, list, torch.Tensor]] = None, clone: bool = True) Union[numpy.ndarray, torch.Tensor]

Gets the viscosity of materials indicated by the indices.

Parameters
  • indices (Optional[Union[np.ndarray, list, torch.Tensor]], optional) – indices to specify which material prims to query. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

  • clone (bool, optional) – True to return a clone of the internal buffer. Otherwise False. Defaults to True.

Returns

viscosity tensor with shape (M, )

Return type

Union[np.ndarray, torch.Tensor]

get_vorticity_confinements(indices: Optional[Union[numpy.ndarray, list, torch.Tensor]] = None, clone: bool = True) Union[numpy.ndarray, torch.Tensor]

Gets the vorticity confinement of materials indicated by the indices.

Parameters
  • indices (Optional[Union[np.ndarray, list, torch.Tensor]], optional) – indices to specify which material prims to query. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

  • clone (bool, optional) – True to return a clone of the internal buffer. Otherwise False. Defaults to True.

Returns

vorticity confinement tensor with shape (M, )

Return type

Union[np.ndarray, torch.Tensor]

initialize(physics_sim_view: Optional[omni.physics.tensors.bindings._physicsTensors.SimulationView] = None) None

Create a physics simulation view if not passed and creates a rigid body view in physX.

Parameters

physics_sim_view (omni.physics.tensors.SimulationView, optional) – current physics simulation view. Defaults to None.

is_physics_handle_valid() bool
Returns

True if the physics handle of the view is valid (i.e physics is initialized for the view). Otherwise False.

Return type

bool

is_valid(indices: Optional[Union[numpy.ndarray, list, torch.Tensor]] = None) bool
Parameters

indices (Optional[Union[np.ndarray, list, torch.Tensor]], optional) – indices to specify which prims to query. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

Returns

True if all prim paths specified in the view correspond to a valid prim in stage. False otherwise.

Return type

bool

property name: str

Returns: str: name given to the view when instantiating it.

post_reset() None

Resets the particles to their initial states.

set_adhesion_offset_scales(values: Optional[Union[numpy.ndarray, torch.Tensor]], indices: Optional[Union[numpy.ndarray, list, torch.Tensor]] = None) None

Sets the adhesion offset scale for the material prims indicated by the indices.

Parameters
  • values (Optional[Union[np.ndarray, torch.Tensor]], optional) – material adhesion offset scale tensor with the shape (M, ).

  • indices (Optional[Union[np.ndarray, list, torch.Tensor]], optional) – indices to specify which material prims to manipulate. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

set_adhesions(values: Optional[Union[numpy.ndarray, torch.Tensor]], indices: Optional[Union[numpy.ndarray, list, torch.Tensor]] = None) None

Sets the particle adhesion for the material prims indicated by the indices.

Parameters
  • values (Optional[Union[np.ndarray, torch.Tensor]], optional) – material particle adhesion scale tensor with the shape (M, ).

  • indices (Optional[Union[np.ndarray, list, torch.Tensor]], optional) – indices to specify which material prims to manipulate. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

set_cohesions(values: Optional[Union[numpy.ndarray, torch.Tensor]], indices: Optional[Union[numpy.ndarray, list, torch.Tensor]] = None) None

Sets the particle cohesion for the material prims indicated by the indices.

Parameters
  • values (Optional[Union[np.ndarray, torch.Tensor]], optional) – material particle cohesion scale tensor with the shape (M, ).

  • indices (Optional[Union[np.ndarray, list, torch.Tensor]], optional) – indices to specify which material prims to manipulate. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

set_dampings(values: Optional[Union[numpy.ndarray, torch.Tensor]], indices: Optional[Union[numpy.ndarray, list, torch.Tensor]] = None) None

Sets the dampings for the material prims indicated by the indices.

Parameters
  • values (Optional[Union[np.ndarray, torch.Tensor]], optional) – material damping tensor with the shape (M, ).

  • indices (Optional[Union[np.ndarray, list, torch.Tensor]], optional) – indices to specify which material prims to manipulate. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

set_drags(values: Optional[Union[numpy.ndarray, torch.Tensor]], indices: Optional[Union[numpy.ndarray, list, torch.Tensor]] = None) None

Sets the drags for the material prims indicated by the indices.

Parameters
  • values (Optional[Union[np.ndarray, torch.Tensor]], optional) – material drag tensor with the shape (M, ).

  • indices (Optional[Union[np.ndarray, list, torch.Tensor]], optional) – indices to specify which material prims to manipulate. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

set_frictions(values: Optional[Union[numpy.ndarray, torch.Tensor]], indices: Optional[Union[numpy.ndarray, list, torch.Tensor]] = None) None

Sets the friction for the material prims indicated by the indices.

Parameters
  • values (Optional[Union[np.ndarray, torch.Tensor]], optional) – material friction tensor with the shape (M, ).

  • indices (Optional[Union[np.ndarray, list, torch.Tensor]], optional) – indices to specify which material prims to manipulate. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

set_gravity_scales(values: Optional[Union[numpy.ndarray, torch.Tensor]], indices: Optional[Union[numpy.ndarray, list, torch.Tensor]] = None) None

Sets the gravity scale for the material prims indicated by the indices.

Parameters
  • values (Optional[Union[np.ndarray, torch.Tensor]], optional) – material gravity scale tensor with the shape (M, ).

  • indices (Optional[Union[np.ndarray, list, torch.Tensor]], optional) – indices to specify which material prims to manipulate. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

set_lifts(values: Optional[Union[numpy.ndarray, torch.Tensor]], indices: Optional[Union[numpy.ndarray, list, torch.Tensor]] = None) None

Sets the lifts for the material prims indicated by the indices.

Parameters
  • values (Optional[Union[np.ndarray, torch.Tensor]], optional) – material lift tensor with the shape (M, ).

  • indices (Optional[Union[np.ndarray, list, torch.Tensor]], optional) – indices to specify which material prims to manipulate. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

set_particle_adhesion_scales(values: Optional[Union[numpy.ndarray, torch.Tensor]], indices: Optional[Union[numpy.ndarray, list, torch.Tensor]] = None) None

Sets the particle adhesion for the material prims indicated by the indices.

Parameters
  • values (Optional[Union[np.ndarray, torch.Tensor]], optional) – material particle adhesion scale tensor with the shape (M, ).

  • indices (Optional[Union[np.ndarray, list, torch.Tensor]], optional) – indices to specify which material prims to manipulate. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

set_particle_friction_scales(values: Optional[Union[numpy.ndarray, torch.Tensor]], indices: Optional[Union[numpy.ndarray, list, torch.Tensor]] = None) None

Sets the particle friction scale for the material prims indicated by the indices.

Parameters
  • values (Optional[Union[np.ndarray, torch.Tensor]], optional) – material particle friction scale tensor with the shape (M, ).

  • indices (Optional[Union[np.ndarray, list, torch.Tensor]], optional) – indices to specify which material prims to manipulate. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

set_surface_tensions(values: Optional[Union[numpy.ndarray, torch.Tensor]], indices: Optional[Union[numpy.ndarray, list, torch.Tensor]] = None) None

Sets the particle surface tension for the material prims indicated by the indices.

Parameters
  • values (Optional[Union[np.ndarray, torch.Tensor]], optional) – material particle surface tension scale tensor with the shape (M, ).

  • indices (Optional[Union[np.ndarray, list, torch.Tensor]], optional) – indices to specify which material prims to manipulate. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

set_viscosities(values: Optional[Union[numpy.ndarray, torch.Tensor]], indices: Optional[Union[numpy.ndarray, list, torch.Tensor]] = None) None

Sets the particle viscosity for the material prims indicated by the indices.

Parameters
  • values (Optional[Union[np.ndarray, torch.Tensor]], optional) – material particle viscosity scale tensor with the shape (M, ).

  • indices (Optional[Union[np.ndarray, list, torch.Tensor]], optional) – indices to specify which material prims to manipulate. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

set_vorticity_confinements(values: Optional[Union[numpy.ndarray, torch.Tensor]], indices: Optional[Union[numpy.ndarray, list, torch.Tensor]] = None) None

Sets the vorticity confinement for the material prims indicated by the indices.

Parameters
  • values (Optional[Union[np.ndarray, torch.Tensor]], optional) – material particle vorticity confinement scale tensor with the shape (M, ).

  • indices (Optional[Union[np.ndarray, list, torch.Tensor]], optional) – indices to specify which material prims to manipulate. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

Deformable Material

class DeformableMaterial(prim_path: str, name: Optional[str] = 'deformable_material', dynamic_friction: Optional[float] = None, youngs_modulus: Optional[float] = None, poissons_ratio: Optional[float] = None, elasticity_damping: Optional[float] = None, damping_scale: Optional[float] = None)

A wrapper around deformable material used to simulate soft bodies.

get_damping_scale() float
Returns

The damping scale coefficient.

Return type

float

get_dynamic_friction() float
Returns

The dynamic friction coefficient.

Return type

float

get_elasticity_damping() float
Returns

The elasticity damping coefficient.

Return type

float

get_poissons_ratio() float
Returns

The poissons ratio.

Return type

float

get_youngs_modululs() float
Returns

The youngs modululs coefficient.

Return type

float

initialize(physics_sim_view=None) None
is_valid() bool
Returns

True is the current prim path corresponds to a valid prim in stage. False otherwise.

Return type

bool

property material: pxr.UsdShade.Material

Returns: UsdShade.Material: The USD Material object.

property name: Optional[str]

Returns: str: name given to the prim when instantiating it. Otherwise None.

post_reset() None

Resets the prim to its default state.

property prim: pxr.Usd.Prim

Returns: Usd.Prim: The USD prim present.

property prim_path: str

Returns: str: The stage path to the material.

set_damping_scale(value: float) None

Sets the damping scale coefficient.

Parameters

value (float) – The damping scale coefficient Range: [0, inf)

set_dynamic_friction(value: float) None

Sets the dynamic_friction coefficient.

The dynamic_friction takes effect in all interactions between particles and rigids or deformables. For solid particle-particle interactions it is multiplied by the particle dynamic_friction scale.

Parameters

value (float) – The dynamic_friction coefficient. Range: [0, inf), Units: dimensionless

set_elasticity_damping(value: float) None

Sets the global velocity elasticity damping coefficient.

Parameters

value (float) – The elasticity damping coefficient. Range: [0, inf), Units: dimensionless

set_poissons_ratio(value: float) None

Sets the poissons ratio coefficient

Parameters

value (float) – The poissons ratio. Range: (0 , 0.5)

set_youngs_modululs(value: float) None

Sets the youngs_modululs for fluid particles.

Parameters

value (float) – The youngs_modululs. Range: [0, inf)

Deformable Material View

class DeformableMaterialView(prim_paths_expr: str, name: str = 'deformable_material_view', dynamic_frictions: Optional[Union[numpy.ndarray, torch.Tensor]] = None, youngs_moduli: Optional[Union[numpy.ndarray, torch.Tensor]] = None, poissons_ratios: Optional[Union[numpy.ndarray, torch.Tensor]] = None, elasticity_dampings: Optional[Union[numpy.ndarray, torch.Tensor]] = None, damping_scales: Optional[Union[numpy.ndarray, torch.Tensor]] = None)

The view class to deal with deformableMaterial prims. Provides high level functions to deal with deformable material (1 or more deformable materials) as well as its attributes/ properties. This object wraps all matching materials found at the regex provided at the prim_paths_expr. This object wraps all matching materials Prims found at the regex provided at the prim_paths_expr.

property count: int

Returns: int: number of rigid shapes for the prims in the view.

get_damping_scales(indices: Optional[Union[numpy.ndarray, list, torch.Tensor]] = None, clone: bool = True) Union[numpy.ndarray, torch.Tensor]

Gets the damping scale of materials indicated by the indices.

Parameters
  • indices (Optional[Union[np.ndarray, list, torch.Tensor]], optional) – indices to specify which material prims to query. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

  • clone (bool, optional) – True to return a clone of the internal buffer. Otherwise False. Defaults to True.

Returns

damping scale tensor with shape (M, )

Return type

Union[np.ndarray, torch.Tensor]

get_dynamic_frictions(indices: Optional[Union[numpy.ndarray, list, torch.Tensor]] = None, clone: bool = True) Union[numpy.ndarray, torch.Tensor]

Gets the dynamic friction of materials indicated by the indices.

Parameters
  • indices (Optional[Union[np.ndarray, list, torch.Tensor]], optional) – indices to specify which material prims to query. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

  • clone (bool, optional) – True to return a clone of the internal buffer. Otherwise False. Defaults to True.

Returns

dynamic friction tensor with shape (M, )

Return type

Union[np.ndarray, torch.Tensor]

get_elasticity_dampings(indices: Optional[Union[numpy.ndarray, list, torch.Tensor]] = None, clone: bool = True) Union[numpy.ndarray, torch.Tensor]

Gets the elasticity dampings of materials indicated by the indices.

Parameters
  • indices (Optional[Union[np.ndarray, list, torch.Tensor]], optional) – indices to specify which material prims to query. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

  • clone (bool, optional) – True to return a clone of the internal buffer. Otherwise False. Defaults to True.

Returns

elasticity dampings tensor with shape (M, )

Return type

Union[np.ndarray, torch.Tensor]

get_poissons_ratios(indices: Optional[Union[numpy.ndarray, list, torch.Tensor]] = None, clone: bool = True) Union[numpy.ndarray, torch.Tensor]

Gets the poissons ratios of materials indicated by the indices.

Parameters
  • indices (Optional[Union[np.ndarray, list, torch.Tensor]], optional) – indices to specify which material prims to query. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

  • clone (bool, optional) – True to return a clone of the internal buffer. Otherwise False. Defaults to True.

Returns

poissons ratio tensor with shape (M, )

Return type

Union[np.ndarray, torch.Tensor]

get_youngs_moduli(indices: Optional[Union[numpy.ndarray, list, torch.Tensor]] = None, clone: bool = True) Union[numpy.ndarray, torch.Tensor]

Gets the Youngs moduli of materials indicated by the indices.

Parameters
  • indices (Optional[Union[np.ndarray, list, torch.Tensor]], optional) – indices to specify which material prims to query. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

  • clone (bool, optional) – True to return a clone of the internal buffer. Otherwise False. Defaults to True.

Returns

Youngs moduli tensor with shape (M, )

Return type

Union[np.ndarray, torch.Tensor]

initialize(physics_sim_view: Optional[omni.physics.tensors.bindings._physicsTensors.SimulationView] = None) None

Create a physics simulation view if not passed and creates a rigid body view in physX.

Parameters

physics_sim_view (omni.physics.tensors.SimulationView, optional) – current physics simulation view. Defaults to None.

is_physics_handle_valid() bool
Returns

True if the physics handle of the view is valid (i.e physics is initialized for the view). Otherwise False.

Return type

bool

is_valid(indices: Optional[Union[numpy.ndarray, list, torch.Tensor]] = None) bool
Parameters

indices (Optional[Union[np.ndarray, list, torch.Tensor]], optional) – indices to specify which prims to query. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

Returns

True if all prim paths specified in the view correspond to a valid prim in stage. False otherwise.

Return type

bool

property name: str

Returns: str: name given to the view when instantiating it.

post_reset() None

Resets the deformables to their initial states.

set_damping_scales(values: Optional[Union[numpy.ndarray, torch.Tensor]], indices: Optional[Union[numpy.ndarray, list, torch.Tensor]] = None) None

Sets the damping scale for the material prims indicated by the indices.

Parameters
  • values (Optional[Union[np.ndarray, torch.Tensor]], optional) – material damping scale tensor with the shape (M, ).

  • indices (Optional[Union[np.ndarray, list, torch.Tensor]], optional) – indices to specify which material prims to manipulate. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

set_dynamic_frictions(values: Optional[Union[numpy.ndarray, torch.Tensor]], indices: Optional[Union[numpy.ndarray, list, torch.Tensor]] = None) None

Sets the dynamic friction for the material prims indicated by the indices.

Parameters
  • values (Optional[Union[np.ndarray, torch.Tensor]], optional) – material dynamic friction tensor with the shape (M, ).

  • indices (Optional[Union[np.ndarray, list, torch.Tensor]], optional) – indices to specify which material prims to manipulate. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

set_elasticity_dampings(values: Optional[Union[numpy.ndarray, torch.Tensor]], indices: Optional[Union[numpy.ndarray, list, torch.Tensor]] = None) None

Sets the elasticity_dampings for the material prims indicated by the indices.

Parameters
  • values (Optional[Union[np.ndarray, torch.Tensor]], optional) – material damping tensor with the shape (M, ).

  • indices (Optional[Union[np.ndarray, list, torch.Tensor]], optional) – indices to specify which material prims to manipulate. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

set_poissons_ratios(values: Optional[Union[numpy.ndarray, torch.Tensor]], indices: Optional[Union[numpy.ndarray, list, torch.Tensor]] = None) None

Sets the poissons ratios for the material prims indicated by the indices.

Parameters
  • values (Optional[Union[np.ndarray, torch.Tensor]], optional) – material poissons ratio tensor with the shape (M, ).

  • indices (Optional[Union[np.ndarray, list, torch.Tensor]], optional) – indices to specify which material prims to manipulate. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

set_youngs_moduli(values: Optional[Union[numpy.ndarray, torch.Tensor]], indices: Optional[Union[numpy.ndarray, list, torch.Tensor]] = None) None

Sets the youngs moduli for the material prims indicated by the indices.

Parameters
  • values (Optional[Union[np.ndarray, torch.Tensor]], optional) – material drag tensor with the shape (M, ).

  • indices (Optional[Union[np.ndarray, list, torch.Tensor]], optional) – indices to specify which material prims to manipulate. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).


Objects

Modules to create/encapsulate visual, fixed, and dynamic shapes (Capsule, Cone, Cuboid, Cylinder, Sphere) as well as ground planes

Type

Classes

Collider API

Rigid Body API

Visual

omni.isaac.core.objects.VisualCapsule
omni.isaac.core.objects.VisualCone
omni.isaac.core.objects.VisualCuboid
omni.isaac.core.objects.VisualCylinder
omni.isaac.core.objects.VisualSphere

No

No

Fixed

omni.isaac.core.objects.FixedCapsule
omni.isaac.core.objects.FixedCone
omni.isaac.core.objects.FixedCuboid
omni.isaac.core.objects.FixedCylinder
omni.isaac.core.objects.FixedSphere

omni.isaac.core.objects.GroundPlane

Yes

No

Dynamic

omni.isaac.core.objects.DynamicCapsule
omni.isaac.core.objects.DynamicCone
omni.isaac.core.objects.DynamicCuboid
omni.isaac.core.objects.DynamicCylinder
omni.isaac.core.objects.DynamicSphere

Yes

Yes


Ground Plane

class GroundPlane(prim_path: str, name: str = 'ground_plane', size: Optional[float] = None, z_position: Optional[float] = None, scale: Optional[numpy.ndarray] = None, visible: Optional[bool] = None, color: Optional[numpy.ndarray] = None, physics_material: Optional[omni.isaac.core.materials.physics_material.PhysicsMaterial] = None, visual_material: Optional[omni.isaac.core.materials.visual_material.VisualMaterial] = None)

High level wrapper to create/encapsulate a ground plane

Parameters
  • prim_path (str) – prim path of the Prim to encapsulate or create

  • name (str, optional) – shortname to be used as a key by Scene class. Note: needs to be unique if the object is added to the Scene. Defaults to “ground_plane”.

  • size (Optional[float], optional) – length of each edge. Defaults to 5000.0.

  • z_position (float, optional) – ground plane position in the z-axis. Defaults to 0.

  • scale (Optional[np.ndarray], optional) – local scale to be applied to the prim’s dimensions. Defaults to None.

  • visible (bool, optional) – set to false for an invisible prim in the stage while rendering. Defaults to True.

  • color (Optional[np.ndarray], optional) – color of the visual plane. Defaults to None.

  • physics_material_path (Optional[PhysicsMaterial], optional) – path of the physics material to be applied to the held prim. Defaults to None. If not specified, a default physics material will be added.

  • visual_material (Optional[VisualMaterial], optional) – visual material to be applied to the held prim. Defaults to None. If not specified, a default visual material will be added.

  • static_friction (float, optional) – static friction coefficient. Defaults to 0.5.

  • dynamic_friction (float, optional) – dynamic friction coefficient. Defaults to 0.5.

  • restitution (float, optional) – restitution coefficient. Defaults to 0.8.

Example:

>>> from omni.isaac.core.objects import GroundPlane
>>> import numpy as np
>>>
>>> # create a ground plane placed at 0 in the z-axis
>>> plane = GroundPlane(prim_path="/World/GroundPlane", z_position=0)
>>> plane
<omni.isaac.core.objects.ground_plane.GroundPlane object at 0x7f15d003fb50>
apply_physics_material(physics_material: omni.isaac.core.materials.physics_material.PhysicsMaterial, weaker_than_descendants: bool = False)

Used to apply physics material to the held prim and optionally its descendants.

Parameters
  • physics_material (PhysicsMaterial) – physics material to be applied to the held prim. This where you want to define friction, restitution..etc. Note: if a physics material is not defined, the defaults will be used from PhysX.

  • weaker_than_descendants (bool, optional) – True if the material shouldn’t override the descendants materials, otherwise False. Defaults to False.

Example:

>>> from omni.isaac.core.materials import PhysicsMaterial
>>>
>>> # create a rigid body physical material
>>> material = PhysicsMaterial(
...     prim_path="/World/physics_material/aluminum",  # path to the material prim to create
...     dynamic_friction=0.4,
...     static_friction=1.1,
...     restitution=0.1
... )
>>> plane.apply_physics_material(material)
property collision_geometry_prim: omni.isaac.core.prims.geometry_prim.GeometryPrim
Returns

wrapped object as a GeometryPrim

Return type

GeometryPrim

Example:

>>> plane.collision_geometry_prim
<omni.isaac.core.prims.geometry_prim.GeometryPrim object at 0x7f15ff3461a0>
get_applied_physics_material() omni.isaac.core.materials.physics_material.PhysicsMaterial

Returns the current applied physics material in case it was applied using apply_physics_material or not.

Returns

the current applied physics material.

Return type

PhysicsMaterial

Example:

>>> plane.get_applied_physics_material()
<omni.isaac.core.materials.physics_material.PhysicsMaterial object at 0x7f517ff62920>
get_default_state() omni.isaac.core.utils.types.XFormPrimState

Get the default prim states (spatial position and orientation).

Returns

an object that contains the default state of the prim (position and orientation)

Return type

XFormPrimState

Example:

>>> state = plane.get_default_state()
>>> state
<omni.isaac.core.utils.types.XFormPrimState object at 0x7f6efff41cf0>
>>>
>>> state.position
[0. 0. 0.]
>>> state.orientation
[1. 0. 0. 0.]
get_world_pose() Tuple[numpy.ndarray, numpy.ndarray]

Get prim’s pose with respect to the world’s frame

Returns

first index is the position in the world frame (with shape (3, )). Second index is quaternion orientation (with shape (4, )) in the world frame

Return type

Tuple[np.ndarray, np.ndarray]

Example:

>>> # if the prim is in position (0.0, 0.0, 0.0) with respect to the world frame
>>> position, orientation = prim.get_world_pose()
>>> position
[0. 0. 0.]
>>> orientation
[1. 0. 0. 0.]
initialize(physics_sim_view=None) None

Create a physics simulation view if not passed and using PhysX tensor API

Note

If the prim has been added to the world scene (e.g., world.scene.add(prim)), it will be automatically initialized when the world is reset (e.g., world.reset()).

Parameters

physics_sim_view (omni.physics.tensors.SimulationView, optional) – current physics simulation view. Defaults to None.

Example:

>>> plane.initialize()
is_valid() bool

Check if the prim path has a valid USD Prim at it

Returns

True is the current prim path corresponds to a valid prim in stage. False otherwise.

Return type

bool

Example:

>>> # given an existing and valid prim
>>> plane.is_valid()
True
property name: Optional[str]
Returns

name given to the prim when instantiating it. Otherwise None.

Return type

str

Example:

>>> plane.name
ground_plane
post_reset() None

Reset the prim to its default state (position and orientation).

Example:

>>> plane.post_reset()
property prim: pxr.Usd.Prim
Returns

USD Prim object that this object holds.

Return type

Usd.Prim

Example:

>>> plane.prim
Usd.Prim(</World/GroundPlane>)
property prim_path: str
Returns

prim path in the stage.

Return type

str

Example:

>>> plane.prim_path
/World/GroundPlane
set_default_state(position: Optional[Sequence[float]] = None, orientation: Optional[Sequence[float]] = None) None

Sets the default state of the prim (position and orientation), that will be used after each reset.

Parameters
  • position (Optional[Sequence[float]], optional) – position in the world frame of the prim. shape is (3, ). Defaults to None, which means left unchanged.

  • orientation (Optional[Sequence[float]], optional) – quaternion orientation in the world frame of the prim. quaternion is scalar-first (w, x, y, z). shape is (4, ). Defaults to None, which means left unchanged.

Example:

>>> # configure default state
>>> plane.set_default_state(position=np.array([0.0, 0.0, -1.0]), orientation=np.array([1, 0, 0, 0]))
>>>
>>> # set default states during post-reset
>>> plane.post_reset()
set_world_pose(position: Optional[Sequence[float]] = None, orientation: Optional[Sequence[float]] = None) None

Ses prim’s pose with respect to the world’s frame

Warning

This method will change (teleport) the prim pose immediately to the indicated value

Parameters
  • position (Optional[Sequence[float]], optional) – position in the world frame of the prim. shape is (3, ). Defaults to None, which means left unchanged.

  • orientation (Optional[Sequence[float]], optional) – quaternion orientation in the world frame of the prim. quaternion is scalar-first (w, x, y, z). shape is (4, ). Defaults to None, which means left unchanged.

Hint

This method belongs to the methods used to set the prim state

Example:

>>> plane.set_world_pose(position=np.array([0.0, 0.0, 0.5]), orientation=np.array([1., 0., 0., 0.]))
property xform_prim: omni.isaac.core.prims.xform_prim.XFormPrim
Returns

wrapped object as a XFormPrim

Return type

XFormPrim

Example:

>>> plane.xform_prim
<omni.isaac.core.prims.xform_prim.XFormPrim object at 0x7f1578d32560>

Visual Capsule

class VisualCapsule(prim_path: str, name: str = 'visual_capsule', position: Optional[Sequence[float]] = None, translation: Optional[Sequence[float]] = None, orientation: Optional[Sequence[float]] = None, scale: Optional[Sequence[float]] = None, visible: Optional[bool] = None, color: Optional[numpy.ndarray] = None, radius: Optional[float] = None, height: Optional[float] = None, visual_material: Optional[omni.isaac.core.materials.visual_material.VisualMaterial] = None)

High level wrapper to create/encapsulate a visual capsule

Note

Visual capsules (Capsule shape) have no collisions (Collider API) or rigid body dynamics (Rigid Body API)

Parameters
  • prim_path (str) – prim path of the Prim to encapsulate or create

  • name (str, optional) – shortname to be used as a key by Scene class. Note: needs to be unique if the object is added to the Scene. Defaults to “visual_capsule”.

  • position (Optional[Sequence[float]], optional) – position in the world frame of the prim. shape is (3, ). Defaults to None, which means left unchanged.

  • translation (Optional[Sequence[float]], optional) – translation in the local frame of the prim (with respect to its parent prim). shape is (3, ). Defaults to None, which means left unchanged.

  • orientation (Optional[Sequence[float]], optional) – quaternion orientation in the world/ local frame of the prim (depends if translation or position is specified). quaternion is scalar-first (w, x, y, z). shape is (4, ). Defaults to None, which means left unchanged.

  • scale (Optional[Sequence[float]], optional) – local scale to be applied to the prim’s dimensions. shape is (3, ). Defaults to None, which means left unchanged.

  • visible (bool, optional) – set to false for an invisible prim in the stage while rendering. Defaults to True.

  • color (Optional[np.ndarray], optional) – color of the visual shape. Defaults to None, which means 50% gray

  • radius (Optional[float], optional) – capsule radius. Defaults to None.

  • height (Optional[float], optional) – capsule height. Defaults to None.

  • visual_material (Optional[VisualMaterial], optional) – visual material to be applied to the held prim. Defaults to None. If not specified, a default visual material will be added.

Example:

>>> from omni.isaac.core.objects import VisualCapsule
>>> import numpy as np
>>>
>>> # create a red visual capsule at the given path
... prim = VisualCapsule(
...     prim_path="/World/Xform/Capsule",
...     radius=0.5,
...     height=1.0,
...     color=np.array([1.0, 0.0, 0.0])
... )
>>> prim
<omni.isaac.core.objects.capsule.VisualCapsule object at 0x7f4ff958b0d0>
apply_physics_material(physics_material: omni.isaac.core.materials.physics_material.PhysicsMaterial, weaker_than_descendants: bool = False)

Used to apply physics material to the held prim and optionally its descendants.

Parameters
  • physics_material (PhysicsMaterial) – physics material to be applied to the held prim. This where you want to define friction, restitution..etc. Note: if a physics material is not defined, the defaults will be used from PhysX.

  • weaker_than_descendants (bool, optional) – True if the material shouldn’t override the descendants materials, otherwise False. Defaults to False.

Example:

>>> from omni.isaac.core.materials import PhysicsMaterial
>>>
>>> # create a rigid body physical material
>>> material = PhysicsMaterial(
...     prim_path="/World/physics_material/aluminum",  # path to the material prim to create
...     dynamic_friction=0.4,
...     static_friction=1.1,
...     restitution=0.1
... )
>>> prim.apply_physics_material(material)
apply_visual_material(visual_material: omni.isaac.core.materials.visual_material.VisualMaterial, weaker_than_descendants: bool = False) None

Apply visual material to the held prim and optionally its descendants.

Parameters
  • visual_material (VisualMaterial) – visual material to be applied to the held prim. Currently supports PreviewSurface, OmniPBR and OmniGlass.

  • weaker_than_descendants (bool, optional) – True if the material shouldn’t override the descendants materials, otherwise False. Defaults to False.

Example:

>>> from omni.isaac.core.materials import OmniGlass
>>>
>>> # create a dark-red glass visual material
>>> material = OmniGlass(
...     prim_path="/World/material/glass",  # path to the material prim to create
...     ior=1.25,
...     depth=0.001,
...     thin_walled=False,
...     color=np.array([0.5, 0.0, 0.0])
... )
>>> prim.apply_visual_material(material)
property geom: pxr.UsdGeom.Gprim

Returns: UsdGeom.Gprim: USD geometry object encapsulated.

get_applied_physics_material() omni.isaac.core.materials.physics_material.PhysicsMaterial

Return the current applied physics material in case it was applied using apply_physics_material or not.

Returns

the current applied physics material.

Return type

PhysicsMaterial

Example:

>>> # given a physics material applied
>>> prim.get_applied_physics_material()
<omni.isaac.core.materials.physics_material.PhysicsMaterial object at 0x7fb66c30cd30>
get_applied_visual_material() omni.isaac.core.materials.visual_material.VisualMaterial

Return the current applied visual material in case it was applied using apply_visual_material or it’s one of the following materials that was already applied before: PreviewSurface, OmniPBR and OmniGlass.

Returns

the current applied visual material if its type is currently supported.

Return type

VisualMaterial

Example:

>>> # given a visual material applied
>>> prim.get_applied_visual_material()
<omni.isaac.core.materials.omni_glass.OmniGlass object at 0x7f36263106a0>
get_collision_approximation() str

Get the collision approximation

Approximation

Full name

Description

"none"

Triangle Mesh

The mesh geometry is used directly as a collider without any approximation

"convexDecomposition"

Convex Decomposition

A convex mesh decomposition is performed. This results in a set of convex mesh colliders

"convexHull"

Convex Hull

A convex hull of the mesh is generated and used as the collider

"boundingSphere"

Bounding Sphere

A bounding sphere is computed around the mesh and used as a collider

"boundingCube"

Bounding Cube

An optimally fitting box collider is computed around the mesh

"meshSimplification"

Mesh Simplification

A mesh simplification step is performed, resulting in a simplified triangle mesh collider

"sdf"

SDF Mesh

SDF (Signed-Distance-Field) use high-detail triangle meshes as collision shape

"sphereFill"

Sphere Approximation

A sphere mesh decomposition is performed. This results in a set of sphere colliders

Returns

approximation used for collision

Return type

str

Example:

>>> prim.get_collision_approximation()
none
get_collision_enabled() bool

Check if the Collision API is enabled

Returns

True if the Collision API is enabled. Otherwise False

Return type

bool

Example:

>>> prim.get_collision_enabled()
True
get_contact_force_matrix(dt: float = 1.0) Union[numpy.ndarray, torch.Tensor]

If the object is initialized with filter_paths_expr list, this method returns the contact forces between the prims in the view and the filter prims. i.e., a matrix of dimension (self._contact_view.num_filters, 3) where num_filters is the determined according to the filter_paths_expr parameter.

Parameters

dt (float) – time step multiplier to convert the underlying impulses to forces. If the default value is used then the forces are in fact contact impulses

Returns

Net contact forces of the prims with shape (self._geometry_prim_view._contact_view.num_filters, 3).

Return type

Union[np.ndarray, torch.Tensor]

get_contact_offset() float

Get the contact offset

Shapes whose distance is less than the sum of their contact offset values will generate contacts

Search for Advanced Collision Detection in PhysX docs for more details

Returns

contact offset of the collision shape. Default value is -inf, means default is picked by simulation.

Return type

float

Example:

>>> prim.get_contact_offset()
-inf
get_default_state() omni.isaac.core.utils.types.XFormPrimState

Get the default prim states (spatial position and orientation).

Returns

an object that contains the default state of the prim (position and orientation)

Return type

XFormPrimState

Example:

>>> state = prim.get_default_state()
>>> state
<omni.isaac.core.utils.types.XFormPrimState object at 0x7f33addda650>
>>>
>>> state.position
[-4.5299529e-08 -1.8347054e-09 -2.8610229e-08]
>>> state.orientation
[1. 0. 0. 0.]
get_height() float

Get the capsule height

Returns

capsule height

Return type

float

Example:

>>> prim.get_height()
1.0
get_local_pose() Tuple[numpy.ndarray, numpy.ndarray]

Get prim’s pose with respect to the local frame (the prim’s parent frame)

Returns

first index is the position in the local frame (with shape (3, )). Second index is quaternion orientation (with shape (4, )) in the local frame

Return type

Tuple[np.ndarray, np.ndarray]

Example:

>>> # if the prim is in position (1.0, 0.5, 0.0) with respect to the world frame
>>> position, orientation = prim.get_local_pose()
>>> position
[0. 0. 0.]
>>> orientation
[0. 0. 0.]
get_local_scale() numpy.ndarray

Get prim’s scale with respect to the local frame (the parent’s frame)

Returns

scale applied to the prim’s dimensions in the local frame. shape is (3, ).

Return type

np.ndarray

Example:

>>> prim.get_local_scale()
[1. 1. 1.]
get_min_torsional_patch_radius() float

Get the minimum radius of the contact patch used to apply torsional friction

Search for “Torsional Patch Radius” in PhysX docs for more details

Returns

minimum radius of the contact patch used to apply torsional friction. Allowed range [0, max_float].

Return type

float

Example:

>>> prim.get_min_torsional_patch_radius()
0.0
get_net_contact_forces(dt: float = 1.0) Union[numpy.ndarray, torch.Tensor]

If contact forces of the prims in the view are tracked, this method returns the net contact forces on prims. i.e., a matrix of dimension (1, 3)

Parameters

dt (float) – time step multiplier to convert the underlying impulses to forces. If the default value is used then the forces are in fact contact impulses

Returns

Net contact forces of the prims with shape (3).

Return type

Union[np.ndarray, torch.Tensor]

get_radius() float

Get the capsule radius

Returns

capsule radius

Return type

float

Example:

>>> prim.get_radius()
0.5
get_rest_offset() float

Get the rest offset

Two shapes will come to rest at a distance equal to the sum of their rest offset values. If the rest offset is 0, they should converge to touching exactly

Search for Advanced Collision Detection in PhysX docs for more details

Returns

rest offset of the collision shape.

Return type

float

Example:

>>> prim.get_rest_offset()
-inf
get_torsional_patch_radius() float

Get the radius of the contact patch used to apply torsional friction

Search for “Torsional Patch Radius” in PhysX docs for more details

Returns

radius of the contact patch used to apply torsional friction. Allowed range [0, max_float].

Return type

float

Example:

>>> prim.get_torsional_patch_radius()
0.0
get_visibility() bool
Returns

true if the prim is visible in stage. false otherwise.

Return type

bool

Example:

>>> # get the visible state of an visible prim on the stage
>>> prim.get_visibility()
True
get_world_pose() Tuple[numpy.ndarray, numpy.ndarray]

Get prim’s pose with respect to the world’s frame

Returns

first index is the position in the world frame (with shape (3, )). Second index is quaternion orientation (with shape (4, )) in the world frame

Return type

Tuple[np.ndarray, np.ndarray]

Example:

>>> # if the prim is in position (1.0, 0.5, 0.0) with respect to the world frame
>>> position, orientation = prim.get_world_pose()
>>> position
[1.  0.5 0. ]
>>> orientation
[1. 0. 0. 0.]
get_world_scale() numpy.ndarray

Get prim’s scale with respect to the world’s frame

Returns

scale applied to the prim’s dimensions in the world frame. shape is (3, ).

Return type

np.ndarray

Example:

>>> prim.get_world_scale()
[1. 1. 1.]
initialize(physics_sim_view=None) None

Create a physics simulation view if not passed and using PhysX tensor API

Note

If the prim has been added to the world scene (e.g., world.scene.add(prim)), it will be automatically initialized when the world is reset (e.g., world.reset()).

Parameters

physics_sim_view (omni.physics.tensors.SimulationView, optional) – current physics simulation view. Defaults to None.

Example:

>>> prim.initialize()
is_valid() bool

Check if the prim path has a valid USD Prim at it

Returns

True is the current prim path corresponds to a valid prim in stage. False otherwise.

Return type

bool

Example:

>>> # given an existing and valid prim
>>> prims.is_valid()
True
is_visual_material_applied() bool

Check if there is a visual material applied

Returns

True if there is a visual material applied. False otherwise.

Return type

bool

Example:

>>> # given a visual material applied
>>> prim.is_visual_material_applied()
True
property name: Optional[str]

Returns: str: name given to the prim when instantiating it. Otherwise None.

Used to query if the prim is a non root articulation link

Returns

True if the prim itself is a non root link

Return type

bool

Example:

>>> # for a wrapped articulation (where the root prim has the Physics Articulation Root property applied)
>>> prim.non_root_articulation_link
False
post_reset() None

Reset the prim to its default state (position and orientation).

Note

For an articulation, in addition to configuring the root prim’s default position and spatial orientation (defined via the set_default_state method), the joint’s positions, velocities, and efforts (defined via the set_joints_default_state method) are imposed

Example:

>>> prim.post_reset()
property prim: pxr.Usd.Prim

Returns: Usd.Prim: USD Prim object that this object holds.

property prim_path: str

Returns: str: prim path in the stage

set_collision_approximation(approximation_type: str) None

Set the collision approximation

Approximation

Full name

Description

"none"

Triangle Mesh

The mesh geometry is used directly as a collider without any approximation

"convexDecomposition"

Convex Decomposition

A convex mesh decomposition is performed. This results in a set of convex mesh colliders

"convexHull"

Convex Hull

A convex hull of the mesh is generated and used as the collider

"boundingSphere"

Bounding Sphere

A bounding sphere is computed around the mesh and used as a collider

"boundingCube"

Bounding Cube

An optimally fitting box collider is computed around the mesh

"meshSimplification"

Mesh Simplification

A mesh simplification step is performed, resulting in a simplified triangle mesh collider

"sdf"

SDF Mesh

SDF (Signed-Distance-Field) use high-detail triangle meshes as collision shape

"sphereFill"

Sphere Approximation

A sphere mesh decomposition is performed. This results in a set of sphere colliders

Note

Use Convex Decomposition or SDF (Signed-Distance-Field) tri-meshes to capture details better

Warning

Switching to Convex Decomposition or SDF (Signed-Distance-Field) will have a simulation performance impact due to higher computational cost

Parameters

approximation_type (str) – approximation used for collision

Example:

>>> prim.set_collision_approximation("convexDecomposition")
set_collision_enabled(enabled: bool) None

Enable/disable the Collision API

Parameters

enabled (bool) – Whether to enable or disable the Collision API

Example:

>>> # disable collisions
>>> prim.set_collision_enabled(False)
set_contact_offset(offset: float) None

Set the contact offset

Shapes whose distance is less than the sum of their contact offset values will generate contacts

Search for Advanced Collision Detection in PhysX docs for more details

Warning

The contact offset must be positive and greater than the rest offset

Parameters

offset (float) – Contact offset of a collision shape. Allowed range [maximum(0, rest_offset), 0]. Default value is -inf, means default is picked by simulation based on the shape extent.

Example:

>>> prim.set_contact_offset(0.02)
set_default_state(position: Optional[Sequence[float]] = None, orientation: Optional[Sequence[float]] = None) None

Set the default state of the prim (position and orientation), that will be used after each reset.

Parameters
  • position (Optional[Sequence[float]], optional) – position in the world frame of the prim. shape is (3, ). Defaults to None, which means left unchanged.

  • orientation (Optional[Sequence[float]], optional) – quaternion orientation in the world frame of the prim. quaternion is scalar-first (w, x, y, z). shape is (4, ). Defaults to None, which means left unchanged.

Example:

>>> # configure default state
>>> prim.set_default_state(position=np.array([1.0, 0.5, 0.0]), orientation=np.array([1, 0, 0, 0]))
>>>
>>> # set default states during post-reset
>>> prim.post_reset()
set_height(height: float) None

Set the capsule height

Parameters

height (float) – capsule height

Example:

>>> prim.set_height(2.0)
set_local_pose(translation: Optional[Sequence[float]] = None, orientation: Optional[Sequence[float]] = None) None

Set prim’s pose with respect to the local frame (the prim’s parent frame).

Warning

This method will change (teleport) the prim pose immediately to the indicated value

Parameters
  • translation (Optional[Sequence[float]], optional) – translation in the local frame of the prim (with respect to its parent prim). shape is (3, ). Defaults to None, which means left unchanged.

  • orientation (Optional[Sequence[float]], optional) – quaternion orientation in the local frame of the prim. quaternion is scalar-first (w, x, y, z). shape is (4, ). Defaults to None, which means left unchanged.

Hint

This method belongs to the methods used to set the prim state

Example:

>>> prim.set_local_pose(translation=np.array([1.0, 0.5, 0.0]), orientation=np.array([1., 0., 0., 0.]))
set_local_scale(scale: Optional[Sequence[float]]) None

Set prim’s scale with respect to the local frame (the prim’s parent frame).

Parameters

scale (Optional[Sequence[float]]) – scale to be applied to the prim’s dimensions. shape is (3, ). Defaults to None, which means left unchanged.

Example:

>>> # scale prim 10 times smaller
>>> prim.set_local_scale(np.array([0.1, 0.1, 0.1]))
set_min_torsional_patch_radius(radius: float) None

Set the minimum radius of the contact patch used to apply torsional friction

Search for “Torsional Patch Radius” in PhysX docs for more details

Parameters

radius (float) – minimum radius of the contact patch used to apply torsional friction. Allowed range [0, max_float].

Example:

>>> prim.set_min_torsional_patch_radius(0.05)
set_radius(radius: float) None

Set the capsule radius

Parameters

radius (float) – capsule radius

Example:

>>> prim.set_radius(1.0)
set_rest_offset(offset: float) None

Set the rest offset

Two shapes will come to rest at a distance equal to the sum of their rest offset values. If the rest offset is 0, they should converge to touching exactly

Search for Advanced Collision Detection in PhysX docs for more details

Warning

The contact offset must be positive and greater than the rest offset

Parameters

offset (float) – Rest offset of a collision shape. Allowed range [-max_float, contact_offset. Default value is -inf, means default is picked by simulation. For rigid bodies its zero.

Example:

>>> prim.set_rest_offset(0.01)
set_torsional_patch_radius(radius: float) None

Set the radius of the contact patch used to apply torsional friction

Search for “Torsional Patch Radius” in PhysX docs for more details

Parameters

radius (float) – radius of the contact patch used to apply torsional friction. Allowed range [0, max_float].

Example:

>>> prim.set_torsional_patch_radius(0.1)
set_visibility(visible: bool) None

Set the visibility of the prim in stage

Parameters

visible (bool) – flag to set the visibility of the usd prim in stage.

Example:

>>> # make prim not visible in the stage
>>> prim.set_visibility(visible=False)
set_world_pose(position: Optional[Sequence[float]] = None, orientation: Optional[Sequence[float]] = None) None

Ses prim’s pose with respect to the world’s frame

Warning

This method will change (teleport) the prim pose immediately to the indicated value

Parameters
  • position (Optional[Sequence[float]], optional) – position in the world frame of the prim. shape is (3, ). Defaults to None, which means left unchanged.

  • orientation (Optional[Sequence[float]], optional) – quaternion orientation in the world frame of the prim. quaternion is scalar-first (w, x, y, z). shape is (4, ). Defaults to None, which means left unchanged.

Hint

This method belongs to the methods used to set the prim state

Example:

>>> prim.set_world_pose(position=np.array([1.0, 0.5, 0.0]), orientation=np.array([1., 0., 0., 0.]))

Visual Cone

class VisualCone(prim_path: str, name: str = 'visual_cone', position: Optional[Sequence[float]] = None, translation: Optional[Sequence[float]] = None, orientation: Optional[Sequence[float]] = None, scale: Optional[Sequence[float]] = None, visible: Optional[bool] = None, color: Optional[numpy.ndarray] = None, radius: Optional[float] = None, height: Optional[float] = None, visual_material: Optional[omni.isaac.core.materials.visual_material.VisualMaterial] = None)

High level wrapper to create/encapsulate a visual cone

Note

Visual cones (Cone shape) have no collisions (Collider API) or rigid body dynamics (Rigid Body API)

Parameters
  • prim_path (str) – prim path of the Prim to encapsulate or create

  • name (str, optional) – shortname to be used as a key by Scene class. Note: needs to be unique if the object is added to the Scene. Defaults to “visual_cone”.

  • position (Optional[Sequence[float]], optional) – position in the world frame of the prim. shape is (3, ). Defaults to None, which means left unchanged.

  • translation (Optional[Sequence[float]], optional) – translation in the local frame of the prim (with respect to its parent prim). shape is (3, ). Defaults to None, which means left unchanged.

  • orientation (Optional[Sequence[float]], optional) – quaternion orientation in the world/ local frame of the prim (depends if translation or position is specified). quaternion is scalar-first (w, x, y, z). shape is (4, ). Defaults to None, which means left unchanged.

  • scale (Optional[Sequence[float]], optional) – local scale to be applied to the prim’s dimensions. shape is (3, ). Defaults to None, which means left unchanged.

  • visible (bool, optional) – set to false for an invisible prim in the stage while rendering. Defaults to True.

  • color (Optional[np.ndarray], optional) – color of the visual shape. Defaults to None, which means 50% gray

  • radius (Optional[float], optional) – base radius. Defaults to None.

  • height (Optional[float], optional) – cone height. Defaults to None.

  • visual_material (Optional[VisualMaterial], optional) – visual material to be applied to the held prim. Defaults to None. If not specified, a default visual material will be added.

Example:

>>> from omni.isaac.core.objects import VisualCone
>>> import numpy as np
>>>
>>> # create a red visual cone at the given path
>>> prim = VisualCone(
...     prim_path="/World/Xform/Cone",
...     radius=0.5,
...     height=1.0,
...     color=np.array([1.0, 0.0, 0.0])
... )
>>> prim
<omni.isaac.core.objects.cone.VisualCone object at 0x7f513413aa70>
apply_physics_material(physics_material: omni.isaac.core.materials.physics_material.PhysicsMaterial, weaker_than_descendants: bool = False)

Used to apply physics material to the held prim and optionally its descendants.

Parameters
  • physics_material (PhysicsMaterial) – physics material to be applied to the held prim. This where you want to define friction, restitution..etc. Note: if a physics material is not defined, the defaults will be used from PhysX.

  • weaker_than_descendants (bool, optional) – True if the material shouldn’t override the descendants materials, otherwise False. Defaults to False.

Example:

>>> from omni.isaac.core.materials import PhysicsMaterial
>>>
>>> # create a rigid body physical material
>>> material = PhysicsMaterial(
...     prim_path="/World/physics_material/aluminum",  # path to the material prim to create
...     dynamic_friction=0.4,
...     static_friction=1.1,
...     restitution=0.1
... )
>>> prim.apply_physics_material(material)
apply_visual_material(visual_material: omni.isaac.core.materials.visual_material.VisualMaterial, weaker_than_descendants: bool = False) None

Apply visual material to the held prim and optionally its descendants.

Parameters
  • visual_material (VisualMaterial) – visual material to be applied to the held prim. Currently supports PreviewSurface, OmniPBR and OmniGlass.

  • weaker_than_descendants (bool, optional) – True if the material shouldn’t override the descendants materials, otherwise False. Defaults to False.

Example:

>>> from omni.isaac.core.materials import OmniGlass
>>>
>>> # create a dark-red glass visual material
>>> material = OmniGlass(
...     prim_path="/World/material/glass",  # path to the material prim to create
...     ior=1.25,
...     depth=0.001,
...     thin_walled=False,
...     color=np.array([0.5, 0.0, 0.0])
... )
>>> prim.apply_visual_material(material)
property geom: pxr.UsdGeom.Gprim

Returns: UsdGeom.Gprim: USD geometry object encapsulated.

get_applied_physics_material() omni.isaac.core.materials.physics_material.PhysicsMaterial

Return the current applied physics material in case it was applied using apply_physics_material or not.

Returns

the current applied physics material.

Return type

PhysicsMaterial

Example:

>>> # given a physics material applied
>>> prim.get_applied_physics_material()
<omni.isaac.core.materials.physics_material.PhysicsMaterial object at 0x7fb66c30cd30>
get_applied_visual_material() omni.isaac.core.materials.visual_material.VisualMaterial

Return the current applied visual material in case it was applied using apply_visual_material or it’s one of the following materials that was already applied before: PreviewSurface, OmniPBR and OmniGlass.

Returns

the current applied visual material if its type is currently supported.

Return type

VisualMaterial

Example:

>>> # given a visual material applied
>>> prim.get_applied_visual_material()
<omni.isaac.core.materials.omni_glass.OmniGlass object at 0x7f36263106a0>
get_collision_approximation() str

Get the collision approximation

Approximation

Full name

Description

"none"

Triangle Mesh

The mesh geometry is used directly as a collider without any approximation

"convexDecomposition"

Convex Decomposition

A convex mesh decomposition is performed. This results in a set of convex mesh colliders

"convexHull"

Convex Hull

A convex hull of the mesh is generated and used as the collider

"boundingSphere"

Bounding Sphere

A bounding sphere is computed around the mesh and used as a collider

"boundingCube"

Bounding Cube

An optimally fitting box collider is computed around the mesh

"meshSimplification"

Mesh Simplification

A mesh simplification step is performed, resulting in a simplified triangle mesh collider

"sdf"

SDF Mesh

SDF (Signed-Distance-Field) use high-detail triangle meshes as collision shape

"sphereFill"

Sphere Approximation

A sphere mesh decomposition is performed. This results in a set of sphere colliders

Returns

approximation used for collision

Return type

str

Example:

>>> prim.get_collision_approximation()
none
get_collision_enabled() bool

Check if the Collision API is enabled

Returns

True if the Collision API is enabled. Otherwise False

Return type

bool

Example:

>>> prim.get_collision_enabled()
True
get_contact_force_matrix(dt: float = 1.0) Union[numpy.ndarray, torch.Tensor]

If the object is initialized with filter_paths_expr list, this method returns the contact forces between the prims in the view and the filter prims. i.e., a matrix of dimension (self._contact_view.num_filters, 3) where num_filters is the determined according to the filter_paths_expr parameter.

Parameters

dt (float) – time step multiplier to convert the underlying impulses to forces. If the default value is used then the forces are in fact contact impulses

Returns

Net contact forces of the prims with shape (self._geometry_prim_view._contact_view.num_filters, 3).

Return type

Union[np.ndarray, torch.Tensor]

get_contact_offset() float

Get the contact offset

Shapes whose distance is less than the sum of their contact offset values will generate contacts

Search for Advanced Collision Detection in PhysX docs for more details

Returns

contact offset of the collision shape. Default value is -inf, means default is picked by simulation.

Return type

float

Example:

>>> prim.get_contact_offset()
-inf
get_default_state() omni.isaac.core.utils.types.XFormPrimState

Get the default prim states (spatial position and orientation).

Returns

an object that contains the default state of the prim (position and orientation)

Return type

XFormPrimState

Example:

>>> state = prim.get_default_state()
>>> state
<omni.isaac.core.utils.types.XFormPrimState object at 0x7f33addda650>
>>>
>>> state.position
[-4.5299529e-08 -1.8347054e-09 -2.8610229e-08]
>>> state.orientation
[1. 0. 0. 0.]
get_height() float

Get the cone height

Returns

cone height

Return type

float

Example:

>>> prim.get_height()
1.0
get_local_pose() Tuple[numpy.ndarray, numpy.ndarray]

Get prim’s pose with respect to the local frame (the prim’s parent frame)

Returns

first index is the position in the local frame (with shape (3, )). Second index is quaternion orientation (with shape (4, )) in the local frame

Return type

Tuple[np.ndarray, np.ndarray]

Example:

>>> # if the prim is in position (1.0, 0.5, 0.0) with respect to the world frame
>>> position, orientation = prim.get_local_pose()
>>> position
[0. 0. 0.]
>>> orientation
[0. 0. 0.]
get_local_scale() numpy.ndarray

Get prim’s scale with respect to the local frame (the parent’s frame)

Returns

scale applied to the prim’s dimensions in the local frame. shape is (3, ).

Return type

np.ndarray

Example:

>>> prim.get_local_scale()
[1. 1. 1.]
get_min_torsional_patch_radius() float

Get the minimum radius of the contact patch used to apply torsional friction

Search for “Torsional Patch Radius” in PhysX docs for more details

Returns

minimum radius of the contact patch used to apply torsional friction. Allowed range [0, max_float].

Return type

float

Example:

>>> prim.get_min_torsional_patch_radius()
0.0
get_net_contact_forces(dt: float = 1.0) Union[numpy.ndarray, torch.Tensor]

If contact forces of the prims in the view are tracked, this method returns the net contact forces on prims. i.e., a matrix of dimension (1, 3)

Parameters

dt (float) – time step multiplier to convert the underlying impulses to forces. If the default value is used then the forces are in fact contact impulses

Returns

Net contact forces of the prims with shape (3).

Return type

Union[np.ndarray, torch.Tensor]

get_radius() float

Get the base radius

Returns

base radius

Return type

float

Example:

>>> prim.get_radius()
0.5
get_rest_offset() float

Get the rest offset

Two shapes will come to rest at a distance equal to the sum of their rest offset values. If the rest offset is 0, they should converge to touching exactly

Search for Advanced Collision Detection in PhysX docs for more details

Returns

rest offset of the collision shape.

Return type

float

Example:

>>> prim.get_rest_offset()
-inf
get_torsional_patch_radius() float

Get the radius of the contact patch used to apply torsional friction

Search for “Torsional Patch Radius” in PhysX docs for more details

Returns

radius of the contact patch used to apply torsional friction. Allowed range [0, max_float].

Return type

float

Example:

>>> prim.get_torsional_patch_radius()
0.0
get_visibility() bool
Returns

true if the prim is visible in stage. false otherwise.

Return type

bool

Example:

>>> # get the visible state of an visible prim on the stage
>>> prim.get_visibility()
True
get_world_pose() Tuple[numpy.ndarray, numpy.ndarray]

Get prim’s pose with respect to the world’s frame

Returns

first index is the position in the world frame (with shape (3, )). Second index is quaternion orientation (with shape (4, )) in the world frame

Return type

Tuple[np.ndarray, np.ndarray]

Example:

>>> # if the prim is in position (1.0, 0.5, 0.0) with respect to the world frame
>>> position, orientation = prim.get_world_pose()
>>> position
[1.  0.5 0. ]
>>> orientation
[1. 0. 0. 0.]
get_world_scale() numpy.ndarray

Get prim’s scale with respect to the world’s frame

Returns

scale applied to the prim’s dimensions in the world frame. shape is (3, ).

Return type

np.ndarray

Example:

>>> prim.get_world_scale()
[1. 1. 1.]
initialize(physics_sim_view=None) None

Create a physics simulation view if not passed and using PhysX tensor API

Note

If the prim has been added to the world scene (e.g., world.scene.add(prim)), it will be automatically initialized when the world is reset (e.g., world.reset()).

Parameters

physics_sim_view (omni.physics.tensors.SimulationView, optional) – current physics simulation view. Defaults to None.

Example:

>>> prim.initialize()
is_valid() bool

Check if the prim path has a valid USD Prim at it

Returns

True is the current prim path corresponds to a valid prim in stage. False otherwise.

Return type

bool

Example:

>>> # given an existing and valid prim
>>> prims.is_valid()
True
is_visual_material_applied() bool

Check if there is a visual material applied

Returns

True if there is a visual material applied. False otherwise.

Return type

bool

Example:

>>> # given a visual material applied
>>> prim.is_visual_material_applied()
True
property name: Optional[str]

Returns: str: name given to the prim when instantiating it. Otherwise None.

Used to query if the prim is a non root articulation link

Returns

True if the prim itself is a non root link

Return type

bool

Example:

>>> # for a wrapped articulation (where the root prim has the Physics Articulation Root property applied)
>>> prim.non_root_articulation_link
False
post_reset() None

Reset the prim to its default state (position and orientation).

Note

For an articulation, in addition to configuring the root prim’s default position and spatial orientation (defined via the set_default_state method), the joint’s positions, velocities, and efforts (defined via the set_joints_default_state method) are imposed

Example:

>>> prim.post_reset()
property prim: pxr.Usd.Prim

Returns: Usd.Prim: USD Prim object that this object holds.

property prim_path: str

Returns: str: prim path in the stage

set_collision_approximation(approximation_type: str) None

Set the collision approximation

Approximation

Full name

Description

"none"

Triangle Mesh

The mesh geometry is used directly as a collider without any approximation

"convexDecomposition"

Convex Decomposition

A convex mesh decomposition is performed. This results in a set of convex mesh colliders

"convexHull"

Convex Hull

A convex hull of the mesh is generated and used as the collider

"boundingSphere"

Bounding Sphere

A bounding sphere is computed around the mesh and used as a collider

"boundingCube"

Bounding Cube

An optimally fitting box collider is computed around the mesh

"meshSimplification"

Mesh Simplification

A mesh simplification step is performed, resulting in a simplified triangle mesh collider

"sdf"

SDF Mesh

SDF (Signed-Distance-Field) use high-detail triangle meshes as collision shape

"sphereFill"

Sphere Approximation

A sphere mesh decomposition is performed. This results in a set of sphere colliders

Note

Use Convex Decomposition or SDF (Signed-Distance-Field) tri-meshes to capture details better

Warning

Switching to Convex Decomposition or SDF (Signed-Distance-Field) will have a simulation performance impact due to higher computational cost

Parameters

approximation_type (str) – approximation used for collision

Example:

>>> prim.set_collision_approximation("convexDecomposition")
set_collision_enabled(enabled: bool) None

Enable/disable the Collision API

Parameters

enabled (bool) – Whether to enable or disable the Collision API

Example:

>>> # disable collisions
>>> prim.set_collision_enabled(False)
set_contact_offset(offset: float) None

Set the contact offset

Shapes whose distance is less than the sum of their contact offset values will generate contacts

Search for Advanced Collision Detection in PhysX docs for more details

Warning

The contact offset must be positive and greater than the rest offset

Parameters

offset (float) – Contact offset of a collision shape. Allowed range [maximum(0, rest_offset), 0]. Default value is -inf, means default is picked by simulation based on the shape extent.

Example:

>>> prim.set_contact_offset(0.02)
set_default_state(position: Optional[Sequence[float]] = None, orientation: Optional[Sequence[float]] = None) None

Set the default state of the prim (position and orientation), that will be used after each reset.

Parameters
  • position (Optional[Sequence[float]], optional) – position in the world frame of the prim. shape is (3, ). Defaults to None, which means left unchanged.

  • orientation (Optional[Sequence[float]], optional) – quaternion orientation in the world frame of the prim. quaternion is scalar-first (w, x, y, z). shape is (4, ). Defaults to None, which means left unchanged.

Example:

>>> # configure default state
>>> prim.set_default_state(position=np.array([1.0, 0.5, 0.0]), orientation=np.array([1, 0, 0, 0]))
>>>
>>> # set default states during post-reset
>>> prim.post_reset()
set_height(height: float) None

Set the cone height

Parameters

height (float) – cone height

Example:

>>> prim.set_height(2.0)
set_local_pose(translation: Optional[Sequence[float]] = None, orientation: Optional[Sequence[float]] = None) None

Set prim’s pose with respect to the local frame (the prim’s parent frame).

Warning

This method will change (teleport) the prim pose immediately to the indicated value

Parameters
  • translation (Optional[Sequence[float]], optional) – translation in the local frame of the prim (with respect to its parent prim). shape is (3, ). Defaults to None, which means left unchanged.

  • orientation (Optional[Sequence[float]], optional) – quaternion orientation in the local frame of the prim. quaternion is scalar-first (w, x, y, z). shape is (4, ). Defaults to None, which means left unchanged.

Hint

This method belongs to the methods used to set the prim state

Example:

>>> prim.set_local_pose(translation=np.array([1.0, 0.5, 0.0]), orientation=np.array([1., 0., 0., 0.]))
set_local_scale(scale: Optional[Sequence[float]]) None

Set prim’s scale with respect to the local frame (the prim’s parent frame).

Parameters

scale (Optional[Sequence[float]]) – scale to be applied to the prim’s dimensions. shape is (3, ). Defaults to None, which means left unchanged.

Example:

>>> # scale prim 10 times smaller
>>> prim.set_local_scale(np.array([0.1, 0.1, 0.1]))
set_min_torsional_patch_radius(radius: float) None

Set the minimum radius of the contact patch used to apply torsional friction

Search for “Torsional Patch Radius” in PhysX docs for more details

Parameters

radius (float) – minimum radius of the contact patch used to apply torsional friction. Allowed range [0, max_float].

Example:

>>> prim.set_min_torsional_patch_radius(0.05)
set_radius(radius: float) None

Set the base radius

Parameters

radius (float) – base radius

Example:

>>> prim.set_radius(1.0)
set_rest_offset(offset: float) None

Set the rest offset

Two shapes will come to rest at a distance equal to the sum of their rest offset values. If the rest offset is 0, they should converge to touching exactly

Search for Advanced Collision Detection in PhysX docs for more details

Warning

The contact offset must be positive and greater than the rest offset

Parameters

offset (float) – Rest offset of a collision shape. Allowed range [-max_float, contact_offset. Default value is -inf, means default is picked by simulation. For rigid bodies its zero.

Example:

>>> prim.set_rest_offset(0.01)
set_torsional_patch_radius(radius: float) None

Set the radius of the contact patch used to apply torsional friction

Search for “Torsional Patch Radius” in PhysX docs for more details

Parameters

radius (float) – radius of the contact patch used to apply torsional friction. Allowed range [0, max_float].

Example:

>>> prim.set_torsional_patch_radius(0.1)
set_visibility(visible: bool) None

Set the visibility of the prim in stage

Parameters

visible (bool) – flag to set the visibility of the usd prim in stage.

Example:

>>> # make prim not visible in the stage
>>> prim.set_visibility(visible=False)
set_world_pose(position: Optional[Sequence[float]] = None, orientation: Optional[Sequence[float]] = None) None

Ses prim’s pose with respect to the world’s frame

Warning

This method will change (teleport) the prim pose immediately to the indicated value

Parameters
  • position (Optional[Sequence[float]], optional) – position in the world frame of the prim. shape is (3, ). Defaults to None, which means left unchanged.

  • orientation (Optional[Sequence[float]], optional) – quaternion orientation in the world frame of the prim. quaternion is scalar-first (w, x, y, z). shape is (4, ). Defaults to None, which means left unchanged.

Hint

This method belongs to the methods used to set the prim state

Example:

>>> prim.set_world_pose(position=np.array([1.0, 0.5, 0.0]), orientation=np.array([1., 0., 0., 0.]))

Visual Cuboid

class VisualCuboid(prim_path: str, name: str = 'visual_cube', position: Optional[Sequence[float]] = None, translation: Optional[Sequence[float]] = None, orientation: Optional[Sequence[float]] = None, scale: Optional[Sequence[float]] = None, visible: Optional[bool] = None, color: Optional[numpy.ndarray] = None, size: Optional[float] = None, visual_material: Optional[omni.isaac.core.materials.visual_material.VisualMaterial] = None)

High level wrapper to create/encapsulate a visual cuboid

Note

Visual cuboids (Cube shape) have no collisions (Collider API) or rigid body dynamics (Rigid Body API)

Parameters
  • prim_path (str) – prim path of the Prim to encapsulate or create

  • name (str, optional) – shortname to be used as a key by Scene class. Note: needs to be unique if the object is added to the Scene. Defaults to “visual_cube”.

  • position (Optional[Sequence[float]], optional) – position in the world frame of the prim. shape is (3, ). Defaults to None, which means left unchanged.

  • translation (Optional[Sequence[float]], optional) – translation in the local frame of the prim (with respect to its parent prim). shape is (3, ). Defaults to None, which means left unchanged.

  • orientation (Optional[Sequence[float]], optional) – quaternion orientation in the world/ local frame of the prim (depends if translation or position is specified). quaternion is scalar-first (w, x, y, z). shape is (4, ). Defaults to None, which means left unchanged.

  • scale (Optional[Sequence[float]], optional) – local scale to be applied to the prim’s dimensions. shape is (3, ). Defaults to None, which means left unchanged.

  • visible (bool, optional) – set to false for an invisible prim in the stage while rendering. Defaults to True.

  • color (Optional[np.ndarray], optional) – color of the visual shape. Defaults to None, which means 50% gray

  • size (Optional[float], optional) – length of each cube edge. Defaults to None.

  • visual_material (Optional[VisualMaterial], optional) – visual material to be applied to the held prim. Defaults to None. If not specified, a default visual material will be added.

Example:

>>> from omni.isaac.core.objects import VisualCuboid
>>> import numpy as np
>>>
>>> # create a red visual cube at the given path
>>> prim = VisualCuboid(prim_path="/World/Xform/Cube", color=np.array([1.0, 0.0, 0.0]))
>>> prim
<omni.isaac.core.objects.cuboid.VisualCuboid object at 0x7f12e756fa00>
apply_physics_material(physics_material: omni.isaac.core.materials.physics_material.PhysicsMaterial, weaker_than_descendants: bool = False)

Used to apply physics material to the held prim and optionally its descendants.

Parameters
  • physics_material (PhysicsMaterial) – physics material to be applied to the held prim. This where you want to define friction, restitution..etc. Note: if a physics material is not defined, the defaults will be used from PhysX.

  • weaker_than_descendants (bool, optional) – True if the material shouldn’t override the descendants materials, otherwise False. Defaults to False.

Example:

>>> from omni.isaac.core.materials import PhysicsMaterial
>>>
>>> # create a rigid body physical material
>>> material = PhysicsMaterial(
...     prim_path="/World/physics_material/aluminum",  # path to the material prim to create
...     dynamic_friction=0.4,
...     static_friction=1.1,
...     restitution=0.1
... )
>>> prim.apply_physics_material(material)
apply_visual_material(visual_material: omni.isaac.core.materials.visual_material.VisualMaterial, weaker_than_descendants: bool = False) None

Apply visual material to the held prim and optionally its descendants.

Parameters
  • visual_material (VisualMaterial) – visual material to be applied to the held prim. Currently supports PreviewSurface, OmniPBR and OmniGlass.

  • weaker_than_descendants (bool, optional) – True if the material shouldn’t override the descendants materials, otherwise False. Defaults to False.

Example:

>>> from omni.isaac.core.materials import OmniGlass
>>>
>>> # create a dark-red glass visual material
>>> material = OmniGlass(
...     prim_path="/World/material/glass",  # path to the material prim to create
...     ior=1.25,
...     depth=0.001,
...     thin_walled=False,
...     color=np.array([0.5, 0.0, 0.0])
... )
>>> prim.apply_visual_material(material)
property geom: pxr.UsdGeom.Gprim

Returns: UsdGeom.Gprim: USD geometry object encapsulated.

get_applied_physics_material() omni.isaac.core.materials.physics_material.PhysicsMaterial

Return the current applied physics material in case it was applied using apply_physics_material or not.

Returns

the current applied physics material.

Return type

PhysicsMaterial

Example:

>>> # given a physics material applied
>>> prim.get_applied_physics_material()
<omni.isaac.core.materials.physics_material.PhysicsMaterial object at 0x7fb66c30cd30>
get_applied_visual_material() omni.isaac.core.materials.visual_material.VisualMaterial

Return the current applied visual material in case it was applied using apply_visual_material or it’s one of the following materials that was already applied before: PreviewSurface, OmniPBR and OmniGlass.

Returns

the current applied visual material if its type is currently supported.

Return type

VisualMaterial

Example:

>>> # given a visual material applied
>>> prim.get_applied_visual_material()
<omni.isaac.core.materials.omni_glass.OmniGlass object at 0x7f36263106a0>
get_collision_approximation() str

Get the collision approximation

Approximation

Full name

Description

"none"

Triangle Mesh

The mesh geometry is used directly as a collider without any approximation

"convexDecomposition"

Convex Decomposition

A convex mesh decomposition is performed. This results in a set of convex mesh colliders

"convexHull"

Convex Hull

A convex hull of the mesh is generated and used as the collider

"boundingSphere"

Bounding Sphere

A bounding sphere is computed around the mesh and used as a collider

"boundingCube"

Bounding Cube

An optimally fitting box collider is computed around the mesh

"meshSimplification"

Mesh Simplification

A mesh simplification step is performed, resulting in a simplified triangle mesh collider

"sdf"

SDF Mesh

SDF (Signed-Distance-Field) use high-detail triangle meshes as collision shape

"sphereFill"

Sphere Approximation

A sphere mesh decomposition is performed. This results in a set of sphere colliders

Returns

approximation used for collision

Return type

str

Example:

>>> prim.get_collision_approximation()
none
get_collision_enabled() bool

Check if the Collision API is enabled

Returns

True if the Collision API is enabled. Otherwise False

Return type

bool

Example:

>>> prim.get_collision_enabled()
True
get_contact_force_matrix(dt: float = 1.0) Union[numpy.ndarray, torch.Tensor]

If the object is initialized with filter_paths_expr list, this method returns the contact forces between the prims in the view and the filter prims. i.e., a matrix of dimension (self._contact_view.num_filters, 3) where num_filters is the determined according to the filter_paths_expr parameter.

Parameters

dt (float) – time step multiplier to convert the underlying impulses to forces. If the default value is used then the forces are in fact contact impulses

Returns

Net contact forces of the prims with shape (self._geometry_prim_view._contact_view.num_filters, 3).

Return type

Union[np.ndarray, torch.Tensor]

get_contact_offset() float

Get the contact offset

Shapes whose distance is less than the sum of their contact offset values will generate contacts

Search for Advanced Collision Detection in PhysX docs for more details

Returns

contact offset of the collision shape. Default value is -inf, means default is picked by simulation.

Return type

float

Example:

>>> prim.get_contact_offset()
-inf
get_default_state() omni.isaac.core.utils.types.XFormPrimState

Get the default prim states (spatial position and orientation).

Returns

an object that contains the default state of the prim (position and orientation)

Return type

XFormPrimState

Example:

>>> state = prim.get_default_state()
>>> state
<omni.isaac.core.utils.types.XFormPrimState object at 0x7f33addda650>
>>>
>>> state.position
[-4.5299529e-08 -1.8347054e-09 -2.8610229e-08]
>>> state.orientation
[1. 0. 0. 0.]
get_local_pose() Tuple[numpy.ndarray, numpy.ndarray]

Get prim’s pose with respect to the local frame (the prim’s parent frame)

Returns

first index is the position in the local frame (with shape (3, )). Second index is quaternion orientation (with shape (4, )) in the local frame

Return type

Tuple[np.ndarray, np.ndarray]

Example:

>>> # if the prim is in position (1.0, 0.5, 0.0) with respect to the world frame
>>> position, orientation = prim.get_local_pose()
>>> position
[0. 0. 0.]
>>> orientation
[0. 0. 0.]
get_local_scale() numpy.ndarray

Get prim’s scale with respect to the local frame (the parent’s frame)

Returns

scale applied to the prim’s dimensions in the local frame. shape is (3, ).

Return type

np.ndarray

Example:

>>> prim.get_local_scale()
[1. 1. 1.]
get_min_torsional_patch_radius() float

Get the minimum radius of the contact patch used to apply torsional friction

Search for “Torsional Patch Radius” in PhysX docs for more details

Returns

minimum radius of the contact patch used to apply torsional friction. Allowed range [0, max_float].

Return type

float

Example:

>>> prim.get_min_torsional_patch_radius()
0.0
get_net_contact_forces(dt: float = 1.0) Union[numpy.ndarray, torch.Tensor]

If contact forces of the prims in the view are tracked, this method returns the net contact forces on prims. i.e., a matrix of dimension (1, 3)

Parameters

dt (float) – time step multiplier to convert the underlying impulses to forces. If the default value is used then the forces are in fact contact impulses

Returns

Net contact forces of the prims with shape (3).

Return type

Union[np.ndarray, torch.Tensor]

get_rest_offset() float

Get the rest offset

Two shapes will come to rest at a distance equal to the sum of their rest offset values. If the rest offset is 0, they should converge to touching exactly

Search for Advanced Collision Detection in PhysX docs for more details

Returns

rest offset of the collision shape.

Return type

float

Example:

>>> prim.get_rest_offset()
-inf
get_size() numpy.ndarray

Get the length of each cube edge

Returns

edge length

Return type

float

Example:

>>> prim.get_size()
1.0
get_torsional_patch_radius() float

Get the radius of the contact patch used to apply torsional friction

Search for “Torsional Patch Radius” in PhysX docs for more details

Returns

radius of the contact patch used to apply torsional friction. Allowed range [0, max_float].

Return type

float

Example:

>>> prim.get_torsional_patch_radius()
0.0
get_visibility() bool
Returns

true if the prim is visible in stage. false otherwise.

Return type

bool

Example:

>>> # get the visible state of an visible prim on the stage
>>> prim.get_visibility()
True
get_world_pose() Tuple[numpy.ndarray, numpy.ndarray]

Get prim’s pose with respect to the world’s frame

Returns

first index is the position in the world frame (with shape (3, )). Second index is quaternion orientation (with shape (4, )) in the world frame

Return type

Tuple[np.ndarray, np.ndarray]

Example:

>>> # if the prim is in position (1.0, 0.5, 0.0) with respect to the world frame
>>> position, orientation = prim.get_world_pose()
>>> position
[1.  0.5 0. ]
>>> orientation
[1. 0. 0. 0.]
get_world_scale() numpy.ndarray

Get prim’s scale with respect to the world’s frame

Returns

scale applied to the prim’s dimensions in the world frame. shape is (3, ).

Return type

np.ndarray

Example:

>>> prim.get_world_scale()
[1. 1. 1.]
initialize(physics_sim_view=None) None

Create a physics simulation view if not passed and using PhysX tensor API

Note

If the prim has been added to the world scene (e.g., world.scene.add(prim)), it will be automatically initialized when the world is reset (e.g., world.reset()).

Parameters

physics_sim_view (omni.physics.tensors.SimulationView, optional) – current physics simulation view. Defaults to None.

Example:

>>> prim.initialize()
is_valid() bool

Check if the prim path has a valid USD Prim at it

Returns

True is the current prim path corresponds to a valid prim in stage. False otherwise.

Return type

bool

Example:

>>> # given an existing and valid prim
>>> prims.is_valid()
True
is_visual_material_applied() bool

Check if there is a visual material applied

Returns

True if there is a visual material applied. False otherwise.

Return type

bool

Example:

>>> # given a visual material applied
>>> prim.is_visual_material_applied()
True
property name: Optional[str]

Returns: str: name given to the prim when instantiating it. Otherwise None.

Used to query if the prim is a non root articulation link

Returns

True if the prim itself is a non root link

Return type

bool

Example:

>>> # for a wrapped articulation (where the root prim has the Physics Articulation Root property applied)
>>> prim.non_root_articulation_link
False
post_reset() None

Reset the prim to its default state (position and orientation).

Note

For an articulation, in addition to configuring the root prim’s default position and spatial orientation (defined via the set_default_state method), the joint’s positions, velocities, and efforts (defined via the set_joints_default_state method) are imposed

Example:

>>> prim.post_reset()
property prim: pxr.Usd.Prim

Returns: Usd.Prim: USD Prim object that this object holds.

property prim_path: str

Returns: str: prim path in the stage

set_collision_approximation(approximation_type: str) None

Set the collision approximation

Approximation

Full name

Description

"none"

Triangle Mesh

The mesh geometry is used directly as a collider without any approximation

"convexDecomposition"

Convex Decomposition

A convex mesh decomposition is performed. This results in a set of convex mesh colliders

"convexHull"

Convex Hull

A convex hull of the mesh is generated and used as the collider

"boundingSphere"

Bounding Sphere

A bounding sphere is computed around the mesh and used as a collider

"boundingCube"

Bounding Cube

An optimally fitting box collider is computed around the mesh

"meshSimplification"

Mesh Simplification

A mesh simplification step is performed, resulting in a simplified triangle mesh collider

"sdf"

SDF Mesh

SDF (Signed-Distance-Field) use high-detail triangle meshes as collision shape

"sphereFill"

Sphere Approximation

A sphere mesh decomposition is performed. This results in a set of sphere colliders

Note

Use Convex Decomposition or SDF (Signed-Distance-Field) tri-meshes to capture details better

Warning

Switching to Convex Decomposition or SDF (Signed-Distance-Field) will have a simulation performance impact due to higher computational cost

Parameters

approximation_type (str) – approximation used for collision

Example:

>>> prim.set_collision_approximation("convexDecomposition")
set_collision_enabled(enabled: bool) None

Enable/disable the Collision API

Parameters

enabled (bool) – Whether to enable or disable the Collision API

Example:

>>> # disable collisions
>>> prim.set_collision_enabled(False)
set_contact_offset(offset: float) None

Set the contact offset

Shapes whose distance is less than the sum of their contact offset values will generate contacts

Search for Advanced Collision Detection in PhysX docs for more details

Warning

The contact offset must be positive and greater than the rest offset

Parameters

offset (float) – Contact offset of a collision shape. Allowed range [maximum(0, rest_offset), 0]. Default value is -inf, means default is picked by simulation based on the shape extent.

Example:

>>> prim.set_contact_offset(0.02)
set_default_state(position: Optional[Sequence[float]] = None, orientation: Optional[Sequence[float]] = None) None

Set the default state of the prim (position and orientation), that will be used after each reset.

Parameters
  • position (Optional[Sequence[float]], optional) – position in the world frame of the prim. shape is (3, ). Defaults to None, which means left unchanged.

  • orientation (Optional[Sequence[float]], optional) – quaternion orientation in the world frame of the prim. quaternion is scalar-first (w, x, y, z). shape is (4, ). Defaults to None, which means left unchanged.

Example:

>>> # configure default state
>>> prim.set_default_state(position=np.array([1.0, 0.5, 0.0]), orientation=np.array([1, 0, 0, 0]))
>>>
>>> # set default states during post-reset
>>> prim.post_reset()
set_local_pose(translation: Optional[Sequence[float]] = None, orientation: Optional[Sequence[float]] = None) None

Set prim’s pose with respect to the local frame (the prim’s parent frame).

Warning

This method will change (teleport) the prim pose immediately to the indicated value

Parameters
  • translation (Optional[Sequence[float]], optional) – translation in the local frame of the prim (with respect to its parent prim). shape is (3, ). Defaults to None, which means left unchanged.

  • orientation (Optional[Sequence[float]], optional) – quaternion orientation in the local frame of the prim. quaternion is scalar-first (w, x, y, z). shape is (4, ). Defaults to None, which means left unchanged.

Hint

This method belongs to the methods used to set the prim state

Example:

>>> prim.set_local_pose(translation=np.array([1.0, 0.5, 0.0]), orientation=np.array([1., 0., 0., 0.]))
set_local_scale(scale: Optional[Sequence[float]]) None

Set prim’s scale with respect to the local frame (the prim’s parent frame).

Parameters

scale (Optional[Sequence[float]]) – scale to be applied to the prim’s dimensions. shape is (3, ). Defaults to None, which means left unchanged.

Example:

>>> # scale prim 10 times smaller
>>> prim.set_local_scale(np.array([0.1, 0.1, 0.1]))
set_min_torsional_patch_radius(radius: float) None

Set the minimum radius of the contact patch used to apply torsional friction

Search for “Torsional Patch Radius” in PhysX docs for more details

Parameters

radius (float) – minimum radius of the contact patch used to apply torsional friction. Allowed range [0, max_float].

Example:

>>> prim.set_min_torsional_patch_radius(0.05)
set_rest_offset(offset: float) None

Set the rest offset

Two shapes will come to rest at a distance equal to the sum of their rest offset values. If the rest offset is 0, they should converge to touching exactly

Search for Advanced Collision Detection in PhysX docs for more details

Warning

The contact offset must be positive and greater than the rest offset

Parameters

offset (float) – Rest offset of a collision shape. Allowed range [-max_float, contact_offset. Default value is -inf, means default is picked by simulation. For rigid bodies its zero.

Example:

>>> prim.set_rest_offset(0.01)
set_size(size: float) None

Set the length of each cube edge

Parameters

size (float) – edge length

Example:

>>> prim.set_size(2.0)
set_torsional_patch_radius(radius: float) None

Set the radius of the contact patch used to apply torsional friction

Search for “Torsional Patch Radius” in PhysX docs for more details

Parameters

radius (float) – radius of the contact patch used to apply torsional friction. Allowed range [0, max_float].

Example:

>>> prim.set_torsional_patch_radius(0.1)
set_visibility(visible: bool) None

Set the visibility of the prim in stage

Parameters

visible (bool) – flag to set the visibility of the usd prim in stage.

Example:

>>> # make prim not visible in the stage
>>> prim.set_visibility(visible=False)
set_world_pose(position: Optional[Sequence[float]] = None, orientation: Optional[Sequence[float]] = None) None

Ses prim’s pose with respect to the world’s frame

Warning

This method will change (teleport) the prim pose immediately to the indicated value

Parameters
  • position (Optional[Sequence[float]], optional) – position in the world frame of the prim. shape is (3, ). Defaults to None, which means left unchanged.

  • orientation (Optional[Sequence[float]], optional) – quaternion orientation in the world frame of the prim. quaternion is scalar-first (w, x, y, z). shape is (4, ). Defaults to None, which means left unchanged.

Hint

This method belongs to the methods used to set the prim state

Example:

>>> prim.set_world_pose(position=np.array([1.0, 0.5, 0.0]), orientation=np.array([1., 0., 0., 0.]))

Visual Cylinder

class VisualCylinder(prim_path: str, name: str = 'visual_cylinder', position: Optional[Sequence[float]] = None, translation: Optional[Sequence[float]] = None, orientation: Optional[Sequence[float]] = None, scale: Optional[Sequence[float]] = None, visible: Optional[bool] = None, color: Optional[numpy.ndarray] = None, radius: Optional[float] = None, height: Optional[float] = None, visual_material: Optional[omni.isaac.core.materials.visual_material.VisualMaterial] = None)

High level wrapper to create/encapsulate a visual cylinder

Note

Visual cylinders (Cylinder shape) have no collisions (Collider API) or rigid body dynamics (Rigid Body API)

Parameters
  • prim_path (str) – prim path of the Prim to encapsulate or create

  • name (str, optional) – shortname to be used as a key by Scene class. Note: needs to be unique if the object is added to the Scene. Defaults to “visual_cylinder”.

  • position (Optional[Sequence[float]], optional) – position in the world frame of the prim. shape is (3, ). Defaults to None, which means left unchanged.

  • translation (Optional[Sequence[float]], optional) – translation in the local frame of the prim (with respect to its parent prim). shape is (3, ). Defaults to None, which means left unchanged.

  • orientation (Optional[Sequence[float]], optional) – quaternion orientation in the world/ local frame of the prim (depends if translation or position is specified). quaternion is scalar-first (w, x, y, z). shape is (4, ). Defaults to None, which means left unchanged.

  • scale (Optional[Sequence[float]], optional) – local scale to be applied to the prim’s dimensions. shape is (3, ). Defaults to None, which means left unchanged.

  • visible (bool, optional) – set to false for an invisible prim in the stage while rendering. Defaults to True.

  • color (Optional[np.ndarray], optional) – color of the visual shape. Defaults to None, which means 50% gray

  • radius (Optional[float], optional) – base radius. Defaults to None.

  • height (Optional[float], optional) – cylinder height. Defaults to None.

  • visual_material (Optional[VisualMaterial], optional) – visual material to be applied to the held prim. Defaults to None. If not specified, a default visual material will be added.

Example:

>>> from omni.isaac.core.objects import VisualCylinder
>>> import numpy as np
>>>
>>> # create a red visual cylinder at the given path
>>> prim = VisualCylinder(
...     prim_path="/World/Xform/Cylinder",
...     radius=0.5,
...     height=1.0,
...     color=np.array([1.0, 0.0, 0.0])
... )
>>> prim
<omni.isaac.core.objects.cylinder.VisualCylinder object at 0x7f4e433f22c0>
apply_physics_material(physics_material: omni.isaac.core.materials.physics_material.PhysicsMaterial, weaker_than_descendants: bool = False)

Used to apply physics material to the held prim and optionally its descendants.

Parameters
  • physics_material (PhysicsMaterial) – physics material to be applied to the held prim. This where you want to define friction, restitution..etc. Note: if a physics material is not defined, the defaults will be used from PhysX.

  • weaker_than_descendants (bool, optional) – True if the material shouldn’t override the descendants materials, otherwise False. Defaults to False.

Example:

>>> from omni.isaac.core.materials import PhysicsMaterial
>>>
>>> # create a rigid body physical material
>>> material = PhysicsMaterial(
...     prim_path="/World/physics_material/aluminum",  # path to the material prim to create
...     dynamic_friction=0.4,
...     static_friction=1.1,
...     restitution=0.1
... )
>>> prim.apply_physics_material(material)
apply_visual_material(visual_material: omni.isaac.core.materials.visual_material.VisualMaterial, weaker_than_descendants: bool = False) None

Apply visual material to the held prim and optionally its descendants.

Parameters
  • visual_material (VisualMaterial) – visual material to be applied to the held prim. Currently supports PreviewSurface, OmniPBR and OmniGlass.

  • weaker_than_descendants (bool, optional) – True if the material shouldn’t override the descendants materials, otherwise False. Defaults to False.

Example:

>>> from omni.isaac.core.materials import OmniGlass
>>>
>>> # create a dark-red glass visual material
>>> material = OmniGlass(
...     prim_path="/World/material/glass",  # path to the material prim to create
...     ior=1.25,
...     depth=0.001,
...     thin_walled=False,
...     color=np.array([0.5, 0.0, 0.0])
... )
>>> prim.apply_visual_material(material)
property geom: pxr.UsdGeom.Gprim

Returns: UsdGeom.Gprim: USD geometry object encapsulated.

get_applied_physics_material() omni.isaac.core.materials.physics_material.PhysicsMaterial

Return the current applied physics material in case it was applied using apply_physics_material or not.

Returns

the current applied physics material.

Return type

PhysicsMaterial

Example:

>>> # given a physics material applied
>>> prim.get_applied_physics_material()
<omni.isaac.core.materials.physics_material.PhysicsMaterial object at 0x7fb66c30cd30>
get_applied_visual_material() omni.isaac.core.materials.visual_material.VisualMaterial

Return the current applied visual material in case it was applied using apply_visual_material or it’s one of the following materials that was already applied before: PreviewSurface, OmniPBR and OmniGlass.

Returns

the current applied visual material if its type is currently supported.

Return type

VisualMaterial

Example:

>>> # given a visual material applied
>>> prim.get_applied_visual_material()
<omni.isaac.core.materials.omni_glass.OmniGlass object at 0x7f36263106a0>
get_collision_approximation() str

Get the collision approximation

Approximation

Full name

Description

"none"

Triangle Mesh

The mesh geometry is used directly as a collider without any approximation

"convexDecomposition"

Convex Decomposition

A convex mesh decomposition is performed. This results in a set of convex mesh colliders

"convexHull"

Convex Hull

A convex hull of the mesh is generated and used as the collider

"boundingSphere"

Bounding Sphere

A bounding sphere is computed around the mesh and used as a collider

"boundingCube"

Bounding Cube

An optimally fitting box collider is computed around the mesh

"meshSimplification"

Mesh Simplification

A mesh simplification step is performed, resulting in a simplified triangle mesh collider

"sdf"

SDF Mesh

SDF (Signed-Distance-Field) use high-detail triangle meshes as collision shape

"sphereFill"

Sphere Approximation

A sphere mesh decomposition is performed. This results in a set of sphere colliders

Returns

approximation used for collision

Return type

str

Example:

>>> prim.get_collision_approximation()
none
get_collision_enabled() bool

Check if the Collision API is enabled

Returns

True if the Collision API is enabled. Otherwise False

Return type

bool

Example:

>>> prim.get_collision_enabled()
True
get_contact_force_matrix(dt: float = 1.0) Union[numpy.ndarray, torch.Tensor]

If the object is initialized with filter_paths_expr list, this method returns the contact forces between the prims in the view and the filter prims. i.e., a matrix of dimension (self._contact_view.num_filters, 3) where num_filters is the determined according to the filter_paths_expr parameter.

Parameters

dt (float) – time step multiplier to convert the underlying impulses to forces. If the default value is used then the forces are in fact contact impulses

Returns

Net contact forces of the prims with shape (self._geometry_prim_view._contact_view.num_filters, 3).

Return type

Union[np.ndarray, torch.Tensor]

get_contact_offset() float

Get the contact offset

Shapes whose distance is less than the sum of their contact offset values will generate contacts

Search for Advanced Collision Detection in PhysX docs for more details

Returns

contact offset of the collision shape. Default value is -inf, means default is picked by simulation.

Return type

float

Example:

>>> prim.get_contact_offset()
-inf
get_default_state() omni.isaac.core.utils.types.XFormPrimState

Get the default prim states (spatial position and orientation).

Returns

an object that contains the default state of the prim (position and orientation)

Return type

XFormPrimState

Example:

>>> state = prim.get_default_state()
>>> state
<omni.isaac.core.utils.types.XFormPrimState object at 0x7f33addda650>
>>>
>>> state.position
[-4.5299529e-08 -1.8347054e-09 -2.8610229e-08]
>>> state.orientation
[1. 0. 0. 0.]
get_height() float

Get the cylinder height

Returns

cylinder height

Return type

float

Example:

>>> prim.get_height()
1.0
get_local_pose() Tuple[numpy.ndarray, numpy.ndarray]

Get prim’s pose with respect to the local frame (the prim’s parent frame)

Returns

first index is the position in the local frame (with shape (3, )). Second index is quaternion orientation (with shape (4, )) in the local frame

Return type

Tuple[np.ndarray, np.ndarray]

Example:

>>> # if the prim is in position (1.0, 0.5, 0.0) with respect to the world frame
>>> position, orientation = prim.get_local_pose()
>>> position
[0. 0. 0.]
>>> orientation
[0. 0. 0.]
get_local_scale() numpy.ndarray

Get prim’s scale with respect to the local frame (the parent’s frame)

Returns

scale applied to the prim’s dimensions in the local frame. shape is (3, ).

Return type

np.ndarray

Example:

>>> prim.get_local_scale()
[1. 1. 1.]
get_min_torsional_patch_radius() float

Get the minimum radius of the contact patch used to apply torsional friction

Search for “Torsional Patch Radius” in PhysX docs for more details

Returns

minimum radius of the contact patch used to apply torsional friction. Allowed range [0, max_float].

Return type

float

Example:

>>> prim.get_min_torsional_patch_radius()
0.0
get_net_contact_forces(dt: float = 1.0) Union[numpy.ndarray, torch.Tensor]

If contact forces of the prims in the view are tracked, this method returns the net contact forces on prims. i.e., a matrix of dimension (1, 3)

Parameters

dt (float) – time step multiplier to convert the underlying impulses to forces. If the default value is used then the forces are in fact contact impulses

Returns

Net contact forces of the prims with shape (3).

Return type

Union[np.ndarray, torch.Tensor]

get_radius() float

Get the base radius

Returns

base radius

Return type

float

Example:

>>> prim.get_radius()
0.5
get_rest_offset() float

Get the rest offset

Two shapes will come to rest at a distance equal to the sum of their rest offset values. If the rest offset is 0, they should converge to touching exactly

Search for Advanced Collision Detection in PhysX docs for more details

Returns

rest offset of the collision shape.

Return type

float

Example:

>>> prim.get_rest_offset()
-inf
get_torsional_patch_radius() float

Get the radius of the contact patch used to apply torsional friction

Search for “Torsional Patch Radius” in PhysX docs for more details

Returns

radius of the contact patch used to apply torsional friction. Allowed range [0, max_float].

Return type

float

Example:

>>> prim.get_torsional_patch_radius()
0.0
get_visibility() bool
Returns

true if the prim is visible in stage. false otherwise.

Return type

bool

Example:

>>> # get the visible state of an visible prim on the stage
>>> prim.get_visibility()
True
get_world_pose() Tuple[numpy.ndarray, numpy.ndarray]

Get prim’s pose with respect to the world’s frame

Returns

first index is the position in the world frame (with shape (3, )). Second index is quaternion orientation (with shape (4, )) in the world frame

Return type

Tuple[np.ndarray, np.ndarray]

Example:

>>> # if the prim is in position (1.0, 0.5, 0.0) with respect to the world frame
>>> position, orientation = prim.get_world_pose()
>>> position
[1.  0.5 0. ]
>>> orientation
[1. 0. 0. 0.]
get_world_scale() numpy.ndarray

Get prim’s scale with respect to the world’s frame

Returns

scale applied to the prim’s dimensions in the world frame. shape is (3, ).

Return type

np.ndarray

Example:

>>> prim.get_world_scale()
[1. 1. 1.]
initialize(physics_sim_view=None) None

Create a physics simulation view if not passed and using PhysX tensor API

Note

If the prim has been added to the world scene (e.g., world.scene.add(prim)), it will be automatically initialized when the world is reset (e.g., world.reset()).

Parameters

physics_sim_view (omni.physics.tensors.SimulationView, optional) – current physics simulation view. Defaults to None.

Example:

>>> prim.initialize()
is_valid() bool

Check if the prim path has a valid USD Prim at it

Returns

True is the current prim path corresponds to a valid prim in stage. False otherwise.

Return type

bool

Example:

>>> # given an existing and valid prim
>>> prims.is_valid()
True
is_visual_material_applied() bool

Check if there is a visual material applied

Returns

True if there is a visual material applied. False otherwise.

Return type

bool

Example:

>>> # given a visual material applied
>>> prim.is_visual_material_applied()
True
property name: Optional[str]

Returns: str: name given to the prim when instantiating it. Otherwise None.

Used to query if the prim is a non root articulation link

Returns

True if the prim itself is a non root link

Return type

bool

Example:

>>> # for a wrapped articulation (where the root prim has the Physics Articulation Root property applied)
>>> prim.non_root_articulation_link
False
post_reset() None

Reset the prim to its default state (position and orientation).

Note

For an articulation, in addition to configuring the root prim’s default position and spatial orientation (defined via the set_default_state method), the joint’s positions, velocities, and efforts (defined via the set_joints_default_state method) are imposed

Example:

>>> prim.post_reset()
property prim: pxr.Usd.Prim

Returns: Usd.Prim: USD Prim object that this object holds.

property prim_path: str

Returns: str: prim path in the stage

set_collision_approximation(approximation_type: str) None

Set the collision approximation

Approximation

Full name

Description

"none"

Triangle Mesh

The mesh geometry is used directly as a collider without any approximation

"convexDecomposition"

Convex Decomposition

A convex mesh decomposition is performed. This results in a set of convex mesh colliders

"convexHull"

Convex Hull

A convex hull of the mesh is generated and used as the collider

"boundingSphere"

Bounding Sphere

A bounding sphere is computed around the mesh and used as a collider

"boundingCube"

Bounding Cube

An optimally fitting box collider is computed around the mesh

"meshSimplification"

Mesh Simplification

A mesh simplification step is performed, resulting in a simplified triangle mesh collider

"sdf"

SDF Mesh

SDF (Signed-Distance-Field) use high-detail triangle meshes as collision shape

"sphereFill"

Sphere Approximation

A sphere mesh decomposition is performed. This results in a set of sphere colliders

Note

Use Convex Decomposition or SDF (Signed-Distance-Field) tri-meshes to capture details better

Warning

Switching to Convex Decomposition or SDF (Signed-Distance-Field) will have a simulation performance impact due to higher computational cost

Parameters

approximation_type (str) – approximation used for collision

Example:

>>> prim.set_collision_approximation("convexDecomposition")
set_collision_enabled(enabled: bool) None

Enable/disable the Collision API

Parameters

enabled (bool) – Whether to enable or disable the Collision API

Example:

>>> # disable collisions
>>> prim.set_collision_enabled(False)
set_contact_offset(offset: float) None

Set the contact offset

Shapes whose distance is less than the sum of their contact offset values will generate contacts

Search for Advanced Collision Detection in PhysX docs for more details

Warning

The contact offset must be positive and greater than the rest offset

Parameters

offset (float) – Contact offset of a collision shape. Allowed range [maximum(0, rest_offset), 0]. Default value is -inf, means default is picked by simulation based on the shape extent.

Example:

>>> prim.set_contact_offset(0.02)
set_default_state(position: Optional[Sequence[float]] = None, orientation: Optional[Sequence[float]] = None) None

Set the default state of the prim (position and orientation), that will be used after each reset.

Parameters
  • position (Optional[Sequence[float]], optional) – position in the world frame of the prim. shape is (3, ). Defaults to None, which means left unchanged.

  • orientation (Optional[Sequence[float]], optional) – quaternion orientation in the world frame of the prim. quaternion is scalar-first (w, x, y, z). shape is (4, ). Defaults to None, which means left unchanged.

Example:

>>> # configure default state
>>> prim.set_default_state(position=np.array([1.0, 0.5, 0.0]), orientation=np.array([1, 0, 0, 0]))
>>>
>>> # set default states during post-reset
>>> prim.post_reset()
set_height(height: float) None

Set the cylinder height

Parameters

height (float) – cylinder height

Example:

>>> prim.set_height(2.0)
set_local_pose(translation: Optional[Sequence[float]] = None, orientation: Optional[Sequence[float]] = None) None

Set prim’s pose with respect to the local frame (the prim’s parent frame).

Warning

This method will change (teleport) the prim pose immediately to the indicated value

Parameters
  • translation (Optional[Sequence[float]], optional) – translation in the local frame of the prim (with respect to its parent prim). shape is (3, ). Defaults to None, which means left unchanged.

  • orientation (Optional[Sequence[float]], optional) – quaternion orientation in the local frame of the prim. quaternion is scalar-first (w, x, y, z). shape is (4, ). Defaults to None, which means left unchanged.

Hint

This method belongs to the methods used to set the prim state

Example:

>>> prim.set_local_pose(translation=np.array([1.0, 0.5, 0.0]), orientation=np.array([1., 0., 0., 0.]))
set_local_scale(scale: Optional[Sequence[float]]) None

Set prim’s scale with respect to the local frame (the prim’s parent frame).

Parameters

scale (Optional[Sequence[float]]) – scale to be applied to the prim’s dimensions. shape is (3, ). Defaults to None, which means left unchanged.

Example:

>>> # scale prim 10 times smaller
>>> prim.set_local_scale(np.array([0.1, 0.1, 0.1]))
set_min_torsional_patch_radius(radius: float) None

Set the minimum radius of the contact patch used to apply torsional friction

Search for “Torsional Patch Radius” in PhysX docs for more details

Parameters

radius (float) – minimum radius of the contact patch used to apply torsional friction. Allowed range [0, max_float].

Example:

>>> prim.set_min_torsional_patch_radius(0.05)
set_radius(radius: float) None

Set the base radius

Parameters

radius (float) – base radius

Example:

>>> prim.set_radius(1.0)
set_rest_offset(offset: float) None

Set the rest offset

Two shapes will come to rest at a distance equal to the sum of their rest offset values. If the rest offset is 0, they should converge to touching exactly

Search for Advanced Collision Detection in PhysX docs for more details

Warning

The contact offset must be positive and greater than the rest offset

Parameters

offset (float) – Rest offset of a collision shape. Allowed range [-max_float, contact_offset. Default value is -inf, means default is picked by simulation. For rigid bodies its zero.

Example:

>>> prim.set_rest_offset(0.01)
set_torsional_patch_radius(radius: float) None

Set the radius of the contact patch used to apply torsional friction

Search for “Torsional Patch Radius” in PhysX docs for more details

Parameters

radius (float) – radius of the contact patch used to apply torsional friction. Allowed range [0, max_float].

Example:

>>> prim.set_torsional_patch_radius(0.1)
set_visibility(visible: bool) None

Set the visibility of the prim in stage

Parameters

visible (bool) – flag to set the visibility of the usd prim in stage.

Example:

>>> # make prim not visible in the stage
>>> prim.set_visibility(visible=False)
set_world_pose(position: Optional[Sequence[float]] = None, orientation: Optional[Sequence[float]] = None) None

Ses prim’s pose with respect to the world’s frame

Warning

This method will change (teleport) the prim pose immediately to the indicated value

Parameters
  • position (Optional[Sequence[float]], optional) – position in the world frame of the prim. shape is (3, ). Defaults to None, which means left unchanged.

  • orientation (Optional[Sequence[float]], optional) – quaternion orientation in the world frame of the prim. quaternion is scalar-first (w, x, y, z). shape is (4, ). Defaults to None, which means left unchanged.

Hint

This method belongs to the methods used to set the prim state

Example:

>>> prim.set_world_pose(position=np.array([1.0, 0.5, 0.0]), orientation=np.array([1., 0., 0., 0.]))

Visual Sphere

class VisualSphere(prim_path: str, name: str = 'visual_sphere', position: Optional[Sequence[float]] = None, translation: Optional[Sequence[float]] = None, orientation: Optional[Sequence[float]] = None, scale: Optional[Sequence[float]] = None, visible: Optional[bool] = True, color: Optional[numpy.ndarray] = None, radius: Optional[float] = None, visual_material: Optional[omni.isaac.core.materials.visual_material.VisualMaterial] = None)

High level wrapper to create/encapsulate a visual sphere

Note

Visual spheres (Sphere shape) have no collisions (Collider API) or rigid body dynamics (Rigid Body API)

Parameters
  • prim_path (str) – prim path of the Prim to encapsulate or create

  • name (str, optional) – shortname to be used as a key by Scene class. Note: needs to be unique if the object is added to the Scene. Defaults to “visual_sphere”.

  • position (Optional[Sequence[float]], optional) – position in the world frame of the prim. shape is (3, ). Defaults to None, which means left unchanged.

  • translation (Optional[Sequence[float]], optional) – translation in the local frame of the prim (with respect to its parent prim). shape is (3, ). Defaults to None, which means left unchanged.

  • orientation (Optional[Sequence[float]], optional) – quaternion orientation in the world/ local frame of the prim (depends if translation or position is specified). quaternion is scalar-first (w, x, y, z). shape is (4, ). Defaults to None, which means left unchanged.

  • scale (Optional[Sequence[float]], optional) – local scale to be applied to the prim’s dimensions. shape is (3, ). Defaults to None, which means left unchanged.

  • visible (bool, optional) – set to false for an invisible prim in the stage while rendering. Defaults to True.

  • color (Optional[np.ndarray], optional) – color of the visual shape. Defaults to None, which means 50% gray

  • radius (Optional[float], optional) – sphere radius. Defaults to None.

  • visual_material (Optional[VisualMaterial], optional) – visual material to be applied to the held prim. Defaults to None. If not specified, a default visual material will be added.

Example:

>>> from omni.isaac.core.objects import VisualSphere
>>> import numpy as np
>>>
>>> # create a red visual sphere at the given path
>>> prim = VisualSphere(prim_path="/World/Xform/Sphere", color=np.array([1.0, 0.0, 0.0]))
>>> prim
<omni.isaac.core.objects.sphere.VisualSphere object at 0x7f4e3eb3ea70>
apply_physics_material(physics_material: omni.isaac.core.materials.physics_material.PhysicsMaterial, weaker_than_descendants: bool = False)

Used to apply physics material to the held prim and optionally its descendants.

Parameters
  • physics_material (PhysicsMaterial) – physics material to be applied to the held prim. This where you want to define friction, restitution..etc. Note: if a physics material is not defined, the defaults will be used from PhysX.

  • weaker_than_descendants (bool, optional) – True if the material shouldn’t override the descendants materials, otherwise False. Defaults to False.

Example:

>>> from omni.isaac.core.materials import PhysicsMaterial
>>>
>>> # create a rigid body physical material
>>> material = PhysicsMaterial(
...     prim_path="/World/physics_material/aluminum",  # path to the material prim to create
...     dynamic_friction=0.4,
...     static_friction=1.1,
...     restitution=0.1
... )
>>> prim.apply_physics_material(material)
apply_visual_material(visual_material: omni.isaac.core.materials.visual_material.VisualMaterial, weaker_than_descendants: bool = False) None

Apply visual material to the held prim and optionally its descendants.

Parameters
  • visual_material (VisualMaterial) – visual material to be applied to the held prim. Currently supports PreviewSurface, OmniPBR and OmniGlass.

  • weaker_than_descendants (bool, optional) – True if the material shouldn’t override the descendants materials, otherwise False. Defaults to False.

Example:

>>> from omni.isaac.core.materials import OmniGlass
>>>
>>> # create a dark-red glass visual material
>>> material = OmniGlass(
...     prim_path="/World/material/glass",  # path to the material prim to create
...     ior=1.25,
...     depth=0.001,
...     thin_walled=False,
...     color=np.array([0.5, 0.0, 0.0])
... )
>>> prim.apply_visual_material(material)
property geom: pxr.UsdGeom.Gprim

Returns: UsdGeom.Gprim: USD geometry object encapsulated.

get_applied_physics_material() omni.isaac.core.materials.physics_material.PhysicsMaterial

Return the current applied physics material in case it was applied using apply_physics_material or not.

Returns

the current applied physics material.

Return type

PhysicsMaterial

Example:

>>> # given a physics material applied
>>> prim.get_applied_physics_material()
<omni.isaac.core.materials.physics_material.PhysicsMaterial object at 0x7fb66c30cd30>
get_applied_visual_material() omni.isaac.core.materials.visual_material.VisualMaterial

Return the current applied visual material in case it was applied using apply_visual_material or it’s one of the following materials that was already applied before: PreviewSurface, OmniPBR and OmniGlass.

Returns

the current applied visual material if its type is currently supported.

Return type

VisualMaterial

Example:

>>> # given a visual material applied
>>> prim.get_applied_visual_material()
<omni.isaac.core.materials.omni_glass.OmniGlass object at 0x7f36263106a0>
get_collision_approximation() str

Get the collision approximation

Approximation

Full name

Description

"none"

Triangle Mesh

The mesh geometry is used directly as a collider without any approximation

"convexDecomposition"

Convex Decomposition

A convex mesh decomposition is performed. This results in a set of convex mesh colliders

"convexHull"

Convex Hull

A convex hull of the mesh is generated and used as the collider

"boundingSphere"

Bounding Sphere

A bounding sphere is computed around the mesh and used as a collider

"boundingCube"

Bounding Cube

An optimally fitting box collider is computed around the mesh

"meshSimplification"

Mesh Simplification

A mesh simplification step is performed, resulting in a simplified triangle mesh collider

"sdf"

SDF Mesh

SDF (Signed-Distance-Field) use high-detail triangle meshes as collision shape

"sphereFill"

Sphere Approximation

A sphere mesh decomposition is performed. This results in a set of sphere colliders

Returns

approximation used for collision

Return type

str

Example:

>>> prim.get_collision_approximation()
none
get_collision_enabled() bool

Check if the Collision API is enabled

Returns

True if the Collision API is enabled. Otherwise False

Return type

bool

Example:

>>> prim.get_collision_enabled()
True
get_contact_force_matrix(dt: float = 1.0) Union[numpy.ndarray, torch.Tensor]

If the object is initialized with filter_paths_expr list, this method returns the contact forces between the prims in the view and the filter prims. i.e., a matrix of dimension (self._contact_view.num_filters, 3) where num_filters is the determined according to the filter_paths_expr parameter.

Parameters

dt (float) – time step multiplier to convert the underlying impulses to forces. If the default value is used then the forces are in fact contact impulses

Returns

Net contact forces of the prims with shape (self._geometry_prim_view._contact_view.num_filters, 3).

Return type

Union[np.ndarray, torch.Tensor]

get_contact_offset() float

Get the contact offset

Shapes whose distance is less than the sum of their contact offset values will generate contacts

Search for Advanced Collision Detection in PhysX docs for more details

Returns

contact offset of the collision shape. Default value is -inf, means default is picked by simulation.

Return type

float

Example:

>>> prim.get_contact_offset()
-inf
get_default_state() omni.isaac.core.utils.types.XFormPrimState

Get the default prim states (spatial position and orientation).

Returns

an object that contains the default state of the prim (position and orientation)

Return type

XFormPrimState

Example:

>>> state = prim.get_default_state()
>>> state
<omni.isaac.core.utils.types.XFormPrimState object at 0x7f33addda650>
>>>
>>> state.position
[-4.5299529e-08 -1.8347054e-09 -2.8610229e-08]
>>> state.orientation
[1. 0. 0. 0.]
get_local_pose() Tuple[numpy.ndarray, numpy.ndarray]

Get prim’s pose with respect to the local frame (the prim’s parent frame)

Returns

first index is the position in the local frame (with shape (3, )). Second index is quaternion orientation (with shape (4, )) in the local frame

Return type

Tuple[np.ndarray, np.ndarray]

Example:

>>> # if the prim is in position (1.0, 0.5, 0.0) with respect to the world frame
>>> position, orientation = prim.get_local_pose()
>>> position
[0. 0. 0.]
>>> orientation
[0. 0. 0.]
get_local_scale() numpy.ndarray

Get prim’s scale with respect to the local frame (the parent’s frame)

Returns

scale applied to the prim’s dimensions in the local frame. shape is (3, ).

Return type

np.ndarray

Example:

>>> prim.get_local_scale()
[1. 1. 1.]
get_min_torsional_patch_radius() float

Get the minimum radius of the contact patch used to apply torsional friction

Search for “Torsional Patch Radius” in PhysX docs for more details

Returns

minimum radius of the contact patch used to apply torsional friction. Allowed range [0, max_float].

Return type

float

Example:

>>> prim.get_min_torsional_patch_radius()
0.0
get_net_contact_forces(dt: float = 1.0) Union[numpy.ndarray, torch.Tensor]

If contact forces of the prims in the view are tracked, this method returns the net contact forces on prims. i.e., a matrix of dimension (1, 3)

Parameters

dt (float) – time step multiplier to convert the underlying impulses to forces. If the default value is used then the forces are in fact contact impulses

Returns

Net contact forces of the prims with shape (3).

Return type

Union[np.ndarray, torch.Tensor]

get_radius() float

Get the sphere radius

Returns

sphere radius

Return type

float

Example:

>>> prim.get_radius()
1.0
get_rest_offset() float

Get the rest offset

Two shapes will come to rest at a distance equal to the sum of their rest offset values. If the rest offset is 0, they should converge to touching exactly

Search for Advanced Collision Detection in PhysX docs for more details

Returns

rest offset of the collision shape.

Return type

float

Example:

>>> prim.get_rest_offset()
-inf
get_torsional_patch_radius() float

Get the radius of the contact patch used to apply torsional friction

Search for “Torsional Patch Radius” in PhysX docs for more details

Returns

radius of the contact patch used to apply torsional friction. Allowed range [0, max_float].

Return type

float

Example:

>>> prim.get_torsional_patch_radius()
0.0
get_visibility() bool
Returns

true if the prim is visible in stage. false otherwise.

Return type

bool

Example:

>>> # get the visible state of an visible prim on the stage
>>> prim.get_visibility()
True
get_world_pose() Tuple[numpy.ndarray, numpy.ndarray]

Get prim’s pose with respect to the world’s frame

Returns

first index is the position in the world frame (with shape (3, )). Second index is quaternion orientation (with shape (4, )) in the world frame

Return type

Tuple[np.ndarray, np.ndarray]

Example:

>>> # if the prim is in position (1.0, 0.5, 0.0) with respect to the world frame
>>> position, orientation = prim.get_world_pose()
>>> position
[1.  0.5 0. ]
>>> orientation
[1. 0. 0. 0.]
get_world_scale() numpy.ndarray

Get prim’s scale with respect to the world’s frame

Returns

scale applied to the prim’s dimensions in the world frame. shape is (3, ).

Return type

np.ndarray

Example:

>>> prim.get_world_scale()
[1. 1. 1.]
initialize(physics_sim_view=None) None

Create a physics simulation view if not passed and using PhysX tensor API

Note

If the prim has been added to the world scene (e.g., world.scene.add(prim)), it will be automatically initialized when the world is reset (e.g., world.reset()).

Parameters

physics_sim_view (omni.physics.tensors.SimulationView, optional) – current physics simulation view. Defaults to None.

Example:

>>> prim.initialize()
is_valid() bool

Check if the prim path has a valid USD Prim at it

Returns

True is the current prim path corresponds to a valid prim in stage. False otherwise.

Return type

bool

Example:

>>> # given an existing and valid prim
>>> prims.is_valid()
True
is_visual_material_applied() bool

Check if there is a visual material applied

Returns

True if there is a visual material applied. False otherwise.

Return type

bool

Example:

>>> # given a visual material applied
>>> prim.is_visual_material_applied()
True
property name: Optional[str]

Returns: str: name given to the prim when instantiating it. Otherwise None.

Used to query if the prim is a non root articulation link

Returns

True if the prim itself is a non root link

Return type

bool

Example:

>>> # for a wrapped articulation (where the root prim has the Physics Articulation Root property applied)
>>> prim.non_root_articulation_link
False
post_reset() None

Reset the prim to its default state (position and orientation).

Note

For an articulation, in addition to configuring the root prim’s default position and spatial orientation (defined via the set_default_state method), the joint’s positions, velocities, and efforts (defined via the set_joints_default_state method) are imposed

Example:

>>> prim.post_reset()
property prim: pxr.Usd.Prim

Returns: Usd.Prim: USD Prim object that this object holds.

property prim_path: str

Returns: str: prim path in the stage

set_collision_approximation(approximation_type: str) None

Set the collision approximation

Approximation

Full name

Description

"none"

Triangle Mesh

The mesh geometry is used directly as a collider without any approximation

"convexDecomposition"

Convex Decomposition

A convex mesh decomposition is performed. This results in a set of convex mesh colliders

"convexHull"

Convex Hull

A convex hull of the mesh is generated and used as the collider

"boundingSphere"

Bounding Sphere

A bounding sphere is computed around the mesh and used as a collider

"boundingCube"

Bounding Cube

An optimally fitting box collider is computed around the mesh

"meshSimplification"

Mesh Simplification

A mesh simplification step is performed, resulting in a simplified triangle mesh collider

"sdf"

SDF Mesh

SDF (Signed-Distance-Field) use high-detail triangle meshes as collision shape

"sphereFill"

Sphere Approximation

A sphere mesh decomposition is performed. This results in a set of sphere colliders

Note

Use Convex Decomposition or SDF (Signed-Distance-Field) tri-meshes to capture details better

Warning

Switching to Convex Decomposition or SDF (Signed-Distance-Field) will have a simulation performance impact due to higher computational cost

Parameters

approximation_type (str) – approximation used for collision

Example:

>>> prim.set_collision_approximation("convexDecomposition")
set_collision_enabled(enabled: bool) None

Enable/disable the Collision API

Parameters

enabled (bool) – Whether to enable or disable the Collision API

Example:

>>> # disable collisions
>>> prim.set_collision_enabled(False)
set_contact_offset(offset: float) None

Set the contact offset

Shapes whose distance is less than the sum of their contact offset values will generate contacts

Search for Advanced Collision Detection in PhysX docs for more details

Warning

The contact offset must be positive and greater than the rest offset

Parameters

offset (float) – Contact offset of a collision shape. Allowed range [maximum(0, rest_offset), 0]. Default value is -inf, means default is picked by simulation based on the shape extent.

Example:

>>> prim.set_contact_offset(0.02)
set_default_state(position: Optional[Sequence[float]] = None, orientation: Optional[Sequence[float]] = None) None

Set the default state of the prim (position and orientation), that will be used after each reset.

Parameters
  • position (Optional[Sequence[float]], optional) – position in the world frame of the prim. shape is (3, ). Defaults to None, which means left unchanged.

  • orientation (Optional[Sequence[float]], optional) – quaternion orientation in the world frame of the prim. quaternion is scalar-first (w, x, y, z). shape is (4, ). Defaults to None, which means left unchanged.

Example:

>>> # configure default state
>>> prim.set_default_state(position=np.array([1.0, 0.5, 0.0]), orientation=np.array([1, 0, 0, 0]))
>>>
>>> # set default states during post-reset
>>> prim.post_reset()
set_local_pose(translation: Optional[Sequence[float]] = None, orientation: Optional[Sequence[float]] = None) None

Set prim’s pose with respect to the local frame (the prim’s parent frame).

Warning

This method will change (teleport) the prim pose immediately to the indicated value

Parameters
  • translation (Optional[Sequence[float]], optional) – translation in the local frame of the prim (with respect to its parent prim). shape is (3, ). Defaults to None, which means left unchanged.

  • orientation (Optional[Sequence[float]], optional) – quaternion orientation in the local frame of the prim. quaternion is scalar-first (w, x, y, z). shape is (4, ). Defaults to None, which means left unchanged.

Hint

This method belongs to the methods used to set the prim state

Example:

>>> prim.set_local_pose(translation=np.array([1.0, 0.5, 0.0]), orientation=np.array([1., 0., 0., 0.]))
set_local_scale(scale: Optional[Sequence[float]]) None

Set prim’s scale with respect to the local frame (the prim’s parent frame).

Parameters

scale (Optional[Sequence[float]]) – scale to be applied to the prim’s dimensions. shape is (3, ). Defaults to None, which means left unchanged.

Example:

>>> # scale prim 10 times smaller
>>> prim.set_local_scale(np.array([0.1, 0.1, 0.1]))
set_min_torsional_patch_radius(radius: float) None

Set the minimum radius of the contact patch used to apply torsional friction

Search for “Torsional Patch Radius” in PhysX docs for more details

Parameters

radius (float) – minimum radius of the contact patch used to apply torsional friction. Allowed range [0, max_float].

Example:

>>> prim.set_min_torsional_patch_radius(0.05)
set_radius(radius: float) None

Set the sphere radius

Parameters

radius (float) – sphere radius

Example:

>>> prim.set_radius(2.0)
set_rest_offset(offset: float) None

Set the rest offset

Two shapes will come to rest at a distance equal to the sum of their rest offset values. If the rest offset is 0, they should converge to touching exactly

Search for Advanced Collision Detection in PhysX docs for more details

Warning

The contact offset must be positive and greater than the rest offset

Parameters

offset (float) – Rest offset of a collision shape. Allowed range [-max_float, contact_offset. Default value is -inf, means default is picked by simulation. For rigid bodies its zero.

Example:

>>> prim.set_rest_offset(0.01)
set_torsional_patch_radius(radius: float) None

Set the radius of the contact patch used to apply torsional friction

Search for “Torsional Patch Radius” in PhysX docs for more details

Parameters

radius (float) – radius of the contact patch used to apply torsional friction. Allowed range [0, max_float].

Example:

>>> prim.set_torsional_patch_radius(0.1)
set_visibility(visible: bool) None

Set the visibility of the prim in stage

Parameters

visible (bool) – flag to set the visibility of the usd prim in stage.

Example:

>>> # make prim not visible in the stage
>>> prim.set_visibility(visible=False)
set_world_pose(position: Optional[Sequence[float]] = None, orientation: Optional[Sequence[float]] = None) None

Ses prim’s pose with respect to the world’s frame

Warning

This method will change (teleport) the prim pose immediately to the indicated value

Parameters
  • position (Optional[Sequence[float]], optional) – position in the world frame of the prim. shape is (3, ). Defaults to None, which means left unchanged.

  • orientation (Optional[Sequence[float]], optional) – quaternion orientation in the world frame of the prim. quaternion is scalar-first (w, x, y, z). shape is (4, ). Defaults to None, which means left unchanged.

Hint

This method belongs to the methods used to set the prim state

Example:

>>> prim.set_world_pose(position=np.array([1.0, 0.5, 0.0]), orientation=np.array([1., 0., 0., 0.]))

Fixed Capsule

class FixedCapsule(prim_path: str, name: str = 'fixed_capsule', position: Optional[numpy.ndarray] = None, translation: Optional[numpy.ndarray] = None, orientation: Optional[numpy.ndarray] = None, scale: Optional[numpy.ndarray] = None, visible: Optional[bool] = None, color: Optional[numpy.ndarray] = None, radius: Optional[numpy.ndarray] = None, height: Optional[float] = None, visual_material: Optional[omni.isaac.core.materials.visual_material.VisualMaterial] = None, physics_material: Optional[omni.isaac.core.materials.physics_material.PhysicsMaterial] = None)

High level wrapper to create/encapsulate a fixed capsule

Note

Fixed capsules (Capsule shape) have collisions (Collider API) but no rigid body dynamics (Rigid Body API)

Parameters
  • prim_path (str) – prim path of the Prim to encapsulate or create

  • name (str, optional) – shortname to be used as a key by Scene class. Note: needs to be unique if the object is added to the Scene. Defaults to “fixed_capsule”.

  • position (Optional[Sequence[float]], optional) – position in the world frame of the prim. shape is (3, ). Defaults to None, which means left unchanged.

  • translation (Optional[Sequence[float]], optional) – translation in the local frame of the prim (with respect to its parent prim). shape is (3, ). Defaults to None, which means left unchanged.

  • orientation (Optional[Sequence[float]], optional) – quaternion orientation in the world/ local frame of the prim (depends if translation or position is specified). quaternion is scalar-first (w, x, y, z). shape is (4, ). Defaults to None, which means left unchanged.

  • scale (Optional[Sequence[float]], optional) – local scale to be applied to the prim’s dimensions. shape is (3, ). Defaults to None, which means left unchanged.

  • visible (bool, optional) – set to false for an invisible prim in the stage while rendering. Defaults to True.

  • color (Optional[np.ndarray], optional) – color of the visual shape. Defaults to None, which means 50% gray

  • radius (Optional[float], optional) – capsule radius. Defaults to None.

  • height (Optional[float], optional) – capsule height. Defaults to None.

  • visual_material (Optional[VisualMaterial], optional) – visual material to be applied to the held prim. Defaults to None. If not specified, a default visual material will be added.

  • physics_material (Optional[PhysicsMaterial], optional) – physics material to be applied to the held prim. Defaults to None. If not specified, a default physics material will be added.

Example:

>>> from omni.isaac.core.objects import FixedCapsule
>>> import numpy as np
>>>
>>> # create a red fixed capsule at the given path
>>> prim = FixedCapsule(
...     prim_path="/World/Xform/Capsule",
...     radius=0.5,
...     height=1.0,
...     color=np.array([1.0, 0.0, 0.0])
... )
>>> print(prim)
<omni.isaac.core.objects.capsule.FixedCapsule object at 0x7f520c0d4790>
apply_physics_material(physics_material: omni.isaac.core.materials.physics_material.PhysicsMaterial, weaker_than_descendants: bool = False)

Used to apply physics material to the held prim and optionally its descendants.

Parameters
  • physics_material (PhysicsMaterial) – physics material to be applied to the held prim. This where you want to define friction, restitution..etc. Note: if a physics material is not defined, the defaults will be used from PhysX.

  • weaker_than_descendants (bool, optional) – True if the material shouldn’t override the descendants materials, otherwise False. Defaults to False.

Example:

>>> from omni.isaac.core.materials import PhysicsMaterial
>>>
>>> # create a rigid body physical material
>>> material = PhysicsMaterial(
...     prim_path="/World/physics_material/aluminum",  # path to the material prim to create
...     dynamic_friction=0.4,
...     static_friction=1.1,
...     restitution=0.1
... )
>>> prim.apply_physics_material(material)
apply_visual_material(visual_material: omni.isaac.core.materials.visual_material.VisualMaterial, weaker_than_descendants: bool = False) None

Apply visual material to the held prim and optionally its descendants.

Parameters
  • visual_material (VisualMaterial) – visual material to be applied to the held prim. Currently supports PreviewSurface, OmniPBR and OmniGlass.

  • weaker_than_descendants (bool, optional) – True if the material shouldn’t override the descendants materials, otherwise False. Defaults to False.

Example:

>>> from omni.isaac.core.materials import OmniGlass
>>>
>>> # create a dark-red glass visual material
>>> material = OmniGlass(
...     prim_path="/World/material/glass",  # path to the material prim to create
...     ior=1.25,
...     depth=0.001,
...     thin_walled=False,
...     color=np.array([0.5, 0.0, 0.0])
... )
>>> prim.apply_visual_material(material)
property geom: pxr.UsdGeom.Gprim

Returns: UsdGeom.Gprim: USD geometry object encapsulated.

get_applied_physics_material() omni.isaac.core.materials.physics_material.PhysicsMaterial

Return the current applied physics material in case it was applied using apply_physics_material or not.

Returns

the current applied physics material.

Return type

PhysicsMaterial

Example:

>>> # given a physics material applied
>>> prim.get_applied_physics_material()
<omni.isaac.core.materials.physics_material.PhysicsMaterial object at 0x7fb66c30cd30>
get_applied_visual_material() omni.isaac.core.materials.visual_material.VisualMaterial

Return the current applied visual material in case it was applied using apply_visual_material or it’s one of the following materials that was already applied before: PreviewSurface, OmniPBR and OmniGlass.

Returns

the current applied visual material if its type is currently supported.

Return type

VisualMaterial

Example:

>>> # given a visual material applied
>>> prim.get_applied_visual_material()
<omni.isaac.core.materials.omni_glass.OmniGlass object at 0x7f36263106a0>
get_collision_approximation() str

Get the collision approximation

Approximation

Full name

Description

"none"

Triangle Mesh

The mesh geometry is used directly as a collider without any approximation

"convexDecomposition"

Convex Decomposition

A convex mesh decomposition is performed. This results in a set of convex mesh colliders

"convexHull"

Convex Hull

A convex hull of the mesh is generated and used as the collider

"boundingSphere"

Bounding Sphere

A bounding sphere is computed around the mesh and used as a collider

"boundingCube"

Bounding Cube

An optimally fitting box collider is computed around the mesh

"meshSimplification"

Mesh Simplification

A mesh simplification step is performed, resulting in a simplified triangle mesh collider

"sdf"

SDF Mesh

SDF (Signed-Distance-Field) use high-detail triangle meshes as collision shape

"sphereFill"

Sphere Approximation

A sphere mesh decomposition is performed. This results in a set of sphere colliders

Returns

approximation used for collision

Return type

str

Example:

>>> prim.get_collision_approximation()
none
get_collision_enabled() bool

Check if the Collision API is enabled

Returns

True if the Collision API is enabled. Otherwise False

Return type

bool

Example:

>>> prim.get_collision_enabled()
True
get_contact_force_matrix(dt: float = 1.0) Union[numpy.ndarray, torch.Tensor]

If the object is initialized with filter_paths_expr list, this method returns the contact forces between the prims in the view and the filter prims. i.e., a matrix of dimension (self._contact_view.num_filters, 3) where num_filters is the determined according to the filter_paths_expr parameter.

Parameters

dt (float) – time step multiplier to convert the underlying impulses to forces. If the default value is used then the forces are in fact contact impulses

Returns

Net contact forces of the prims with shape (self._geometry_prim_view._contact_view.num_filters, 3).

Return type

Union[np.ndarray, torch.Tensor]

get_contact_offset() float

Get the contact offset

Shapes whose distance is less than the sum of their contact offset values will generate contacts

Search for Advanced Collision Detection in PhysX docs for more details

Returns

contact offset of the collision shape. Default value is -inf, means default is picked by simulation.

Return type

float

Example:

>>> prim.get_contact_offset()
-inf
get_default_state() omni.isaac.core.utils.types.XFormPrimState

Get the default prim states (spatial position and orientation).

Returns

an object that contains the default state of the prim (position and orientation)

Return type

XFormPrimState

Example:

>>> state = prim.get_default_state()
>>> state
<omni.isaac.core.utils.types.XFormPrimState object at 0x7f33addda650>
>>>
>>> state.position
[-4.5299529e-08 -1.8347054e-09 -2.8610229e-08]
>>> state.orientation
[1. 0. 0. 0.]
get_height() float

Get the capsule height

Returns

capsule height

Return type

float

Example:

>>> prim.get_height()
1.0
get_local_pose() Tuple[numpy.ndarray, numpy.ndarray]

Get prim’s pose with respect to the local frame (the prim’s parent frame)

Returns

first index is the position in the local frame (with shape (3, )). Second index is quaternion orientation (with shape (4, )) in the local frame

Return type

Tuple[np.ndarray, np.ndarray]

Example:

>>> # if the prim is in position (1.0, 0.5, 0.0) with respect to the world frame
>>> position, orientation = prim.get_local_pose()
>>> position
[0. 0. 0.]
>>> orientation
[0. 0. 0.]
get_local_scale() numpy.ndarray

Get prim’s scale with respect to the local frame (the parent’s frame)

Returns

scale applied to the prim’s dimensions in the local frame. shape is (3, ).

Return type

np.ndarray

Example:

>>> prim.get_local_scale()
[1. 1. 1.]
get_min_torsional_patch_radius() float

Get the minimum radius of the contact patch used to apply torsional friction

Search for “Torsional Patch Radius” in PhysX docs for more details

Returns

minimum radius of the contact patch used to apply torsional friction. Allowed range [0, max_float].

Return type

float

Example:

>>> prim.get_min_torsional_patch_radius()
0.0
get_net_contact_forces(dt: float = 1.0) Union[numpy.ndarray, torch.Tensor]

If contact forces of the prims in the view are tracked, this method returns the net contact forces on prims. i.e., a matrix of dimension (1, 3)

Parameters

dt (float) – time step multiplier to convert the underlying impulses to forces. If the default value is used then the forces are in fact contact impulses

Returns

Net contact forces of the prims with shape (3).

Return type

Union[np.ndarray, torch.Tensor]

get_radius() float

Get the capsule radius

Returns

capsule radius

Return type

float

Example:

>>> prim.get_radius()
0.5
get_rest_offset() float

Get the rest offset

Two shapes will come to rest at a distance equal to the sum of their rest offset values. If the rest offset is 0, they should converge to touching exactly

Search for Advanced Collision Detection in PhysX docs for more details

Returns

rest offset of the collision shape.

Return type

float

Example:

>>> prim.get_rest_offset()
-inf
get_torsional_patch_radius() float

Get the radius of the contact patch used to apply torsional friction

Search for “Torsional Patch Radius” in PhysX docs for more details

Returns

radius of the contact patch used to apply torsional friction. Allowed range [0, max_float].

Return type

float

Example:

>>> prim.get_torsional_patch_radius()
0.0
get_visibility() bool
Returns

true if the prim is visible in stage. false otherwise.

Return type

bool

Example:

>>> # get the visible state of an visible prim on the stage
>>> prim.get_visibility()
True
get_world_pose() Tuple[numpy.ndarray, numpy.ndarray]

Get prim’s pose with respect to the world’s frame

Returns

first index is the position in the world frame (with shape (3, )). Second index is quaternion orientation (with shape (4, )) in the world frame

Return type

Tuple[np.ndarray, np.ndarray]

Example:

>>> # if the prim is in position (1.0, 0.5, 0.0) with respect to the world frame
>>> position, orientation = prim.get_world_pose()
>>> position
[1.  0.5 0. ]
>>> orientation
[1. 0. 0. 0.]
get_world_scale() numpy.ndarray

Get prim’s scale with respect to the world’s frame

Returns

scale applied to the prim’s dimensions in the world frame. shape is (3, ).

Return type

np.ndarray

Example:

>>> prim.get_world_scale()
[1. 1. 1.]
initialize(physics_sim_view=None) None

Create a physics simulation view if not passed and using PhysX tensor API

Note

If the prim has been added to the world scene (e.g., world.scene.add(prim)), it will be automatically initialized when the world is reset (e.g., world.reset()).

Parameters

physics_sim_view (omni.physics.tensors.SimulationView, optional) – current physics simulation view. Defaults to None.

Example:

>>> prim.initialize()
is_valid() bool

Check if the prim path has a valid USD Prim at it

Returns

True is the current prim path corresponds to a valid prim in stage. False otherwise.

Return type

bool

Example:

>>> # given an existing and valid prim
>>> prims.is_valid()
True
is_visual_material_applied() bool

Check if there is a visual material applied

Returns

True if there is a visual material applied. False otherwise.

Return type

bool

Example:

>>> # given a visual material applied
>>> prim.is_visual_material_applied()
True
property name: Optional[str]

Returns: str: name given to the prim when instantiating it. Otherwise None.

Used to query if the prim is a non root articulation link

Returns

True if the prim itself is a non root link

Return type

bool

Example:

>>> # for a wrapped articulation (where the root prim has the Physics Articulation Root property applied)
>>> prim.non_root_articulation_link
False
post_reset() None

Reset the prim to its default state (position and orientation).

Note

For an articulation, in addition to configuring the root prim’s default position and spatial orientation (defined via the set_default_state method), the joint’s positions, velocities, and efforts (defined via the set_joints_default_state method) are imposed

Example:

>>> prim.post_reset()
property prim: pxr.Usd.Prim

Returns: Usd.Prim: USD Prim object that this object holds.

property prim_path: str

Returns: str: prim path in the stage

set_collision_approximation(approximation_type: str) None

Set the collision approximation

Approximation

Full name

Description

"none"

Triangle Mesh

The mesh geometry is used directly as a collider without any approximation

"convexDecomposition"

Convex Decomposition

A convex mesh decomposition is performed. This results in a set of convex mesh colliders

"convexHull"

Convex Hull

A convex hull of the mesh is generated and used as the collider

"boundingSphere"

Bounding Sphere

A bounding sphere is computed around the mesh and used as a collider

"boundingCube"

Bounding Cube

An optimally fitting box collider is computed around the mesh

"meshSimplification"

Mesh Simplification

A mesh simplification step is performed, resulting in a simplified triangle mesh collider

"sdf"

SDF Mesh

SDF (Signed-Distance-Field) use high-detail triangle meshes as collision shape

"sphereFill"

Sphere Approximation

A sphere mesh decomposition is performed. This results in a set of sphere colliders

Note

Use Convex Decomposition or SDF (Signed-Distance-Field) tri-meshes to capture details better

Warning

Switching to Convex Decomposition or SDF (Signed-Distance-Field) will have a simulation performance impact due to higher computational cost

Parameters

approximation_type (str) – approximation used for collision

Example:

>>> prim.set_collision_approximation("convexDecomposition")
set_collision_enabled(enabled: bool) None

Enable/disable the Collision API

Parameters

enabled (bool) – Whether to enable or disable the Collision API

Example:

>>> # disable collisions
>>> prim.set_collision_enabled(False)
set_contact_offset(offset: float) None

Set the contact offset

Shapes whose distance is less than the sum of their contact offset values will generate contacts

Search for Advanced Collision Detection in PhysX docs for more details

Warning

The contact offset must be positive and greater than the rest offset

Parameters

offset (float) – Contact offset of a collision shape. Allowed range [maximum(0, rest_offset), 0]. Default value is -inf, means default is picked by simulation based on the shape extent.

Example:

>>> prim.set_contact_offset(0.02)
set_default_state(position: Optional[Sequence[float]] = None, orientation: Optional[Sequence[float]] = None) None

Set the default state of the prim (position and orientation), that will be used after each reset.

Parameters
  • position (Optional[Sequence[float]], optional) – position in the world frame of the prim. shape is (3, ). Defaults to None, which means left unchanged.

  • orientation (Optional[Sequence[float]], optional) – quaternion orientation in the world frame of the prim. quaternion is scalar-first (w, x, y, z). shape is (4, ). Defaults to None, which means left unchanged.

Example:

>>> # configure default state
>>> prim.set_default_state(position=np.array([1.0, 0.5, 0.0]), orientation=np.array([1, 0, 0, 0]))
>>>
>>> # set default states during post-reset
>>> prim.post_reset()
set_height(height: float) None

Set the capsule height

Parameters

height (float) – capsule height

Example:

>>> prim.set_height(2.0)
set_local_pose(translation: Optional[Sequence[float]] = None, orientation: Optional[Sequence[float]] = None) None

Set prim’s pose with respect to the local frame (the prim’s parent frame).

Warning

This method will change (teleport) the prim pose immediately to the indicated value

Parameters
  • translation (Optional[Sequence[float]], optional) – translation in the local frame of the prim (with respect to its parent prim). shape is (3, ). Defaults to None, which means left unchanged.

  • orientation (Optional[Sequence[float]], optional) – quaternion orientation in the local frame of the prim. quaternion is scalar-first (w, x, y, z). shape is (4, ). Defaults to None, which means left unchanged.

Hint

This method belongs to the methods used to set the prim state

Example:

>>> prim.set_local_pose(translation=np.array([1.0, 0.5, 0.0]), orientation=np.array([1., 0., 0., 0.]))
set_local_scale(scale: Optional[Sequence[float]]) None

Set prim’s scale with respect to the local frame (the prim’s parent frame).

Parameters

scale (Optional[Sequence[float]]) – scale to be applied to the prim’s dimensions. shape is (3, ). Defaults to None, which means left unchanged.

Example:

>>> # scale prim 10 times smaller
>>> prim.set_local_scale(np.array([0.1, 0.1, 0.1]))
set_min_torsional_patch_radius(radius: float) None

Set the minimum radius of the contact patch used to apply torsional friction

Search for “Torsional Patch Radius” in PhysX docs for more details

Parameters

radius (float) – minimum radius of the contact patch used to apply torsional friction. Allowed range [0, max_float].

Example:

>>> prim.set_min_torsional_patch_radius(0.05)
set_radius(radius: float) None

Set the capsule radius

Parameters

radius (float) – capsule radius

Example:

>>> prim.set_radius(1.0)
set_rest_offset(offset: float) None

Set the rest offset

Two shapes will come to rest at a distance equal to the sum of their rest offset values. If the rest offset is 0, they should converge to touching exactly

Search for Advanced Collision Detection in PhysX docs for more details

Warning

The contact offset must be positive and greater than the rest offset

Parameters

offset (float) – Rest offset of a collision shape. Allowed range [-max_float, contact_offset. Default value is -inf, means default is picked by simulation. For rigid bodies its zero.

Example:

>>> prim.set_rest_offset(0.01)
set_torsional_patch_radius(radius: float) None

Set the radius of the contact patch used to apply torsional friction

Search for “Torsional Patch Radius” in PhysX docs for more details

Parameters

radius (float) – radius of the contact patch used to apply torsional friction. Allowed range [0, max_float].

Example:

>>> prim.set_torsional_patch_radius(0.1)
set_visibility(visible: bool) None

Set the visibility of the prim in stage

Parameters

visible (bool) – flag to set the visibility of the usd prim in stage.

Example:

>>> # make prim not visible in the stage
>>> prim.set_visibility(visible=False)
set_world_pose(position: Optional[Sequence[float]] = None, orientation: Optional[Sequence[float]] = None) None

Ses prim’s pose with respect to the world’s frame

Warning

This method will change (teleport) the prim pose immediately to the indicated value

Parameters
  • position (Optional[Sequence[float]], optional) – position in the world frame of the prim. shape is (3, ). Defaults to None, which means left unchanged.

  • orientation (Optional[Sequence[float]], optional) – quaternion orientation in the world frame of the prim. quaternion is scalar-first (w, x, y, z). shape is (4, ). Defaults to None, which means left unchanged.

Hint

This method belongs to the methods used to set the prim state

Example:

>>> prim.set_world_pose(position=np.array([1.0, 0.5, 0.0]), orientation=np.array([1., 0., 0., 0.]))

Fixed Cone

class FixedCone(prim_path: str, name: str = 'fixed_cone', position: Optional[numpy.ndarray] = None, translation: Optional[numpy.ndarray] = None, orientation: Optional[numpy.ndarray] = None, scale: Optional[numpy.ndarray] = None, visible: Optional[bool] = None, color: Optional[numpy.ndarray] = None, radius: Optional[numpy.ndarray] = None, height: Optional[float] = None, visual_material: Optional[omni.isaac.core.materials.visual_material.VisualMaterial] = None, physics_material: Optional[omni.isaac.core.materials.physics_material.PhysicsMaterial] = None)

High level wrapper to create/encapsulate a fixed cone

Note

Fixed cones (Cone shape) have collisions (Collider API) but no rigid body dynamics (Rigid Body API)

Parameters
  • prim_path (str) – prim path of the Prim to encapsulate or create

  • name (str, optional) – shortname to be used as a key by Scene class. Note: needs to be unique if the object is added to the Scene. Defaults to “fixed_cone”.

  • position (Optional[Sequence[float]], optional) – position in the world frame of the prim. shape is (3, ). Defaults to None, which means left unchanged.

  • translation (Optional[Sequence[float]], optional) – translation in the local frame of the prim (with respect to its parent prim). shape is (3, ). Defaults to None, which means left unchanged.

  • orientation (Optional[Sequence[float]], optional) – quaternion orientation in the world/ local frame of the prim (depends if translation or position is specified). quaternion is scalar-first (w, x, y, z). shape is (4, ). Defaults to None, which means left unchanged.

  • scale (Optional[Sequence[float]], optional) – local scale to be applied to the prim’s dimensions. shape is (3, ). Defaults to None, which means left unchanged.

  • visible (bool, optional) – set to false for an invisible prim in the stage while rendering. Defaults to True.

  • color (Optional[np.ndarray], optional) – color of the visual shape. Defaults to None, which means 50% gray

  • radius (Optional[float], optional) – base radius. Defaults to None.

  • height (Optional[float], optional) – cone height. Defaults to None.

  • visual_material (Optional[VisualMaterial], optional) – visual material to be applied to the held prim. Defaults to None. If not specified, a default visual material will be added.

  • physics_material (Optional[PhysicsMaterial], optional) – physics material to be applied to the held prim. Defaults to None. If not specified, a default physics material will be added.

Example:

>>> from omni.isaac.core.objects import FixedCone
>>> import numpy as np
>>>
>>> # create a red fixed cone at the given path
>>> prim = FixedCone(
...     prim_path="/World/Xform/Cone",
...     radius=0.5,
...     height=1.0,
...     color=np.array([1.0, 0.0, 0.0])
... )
>>> prim
<omni.isaac.core.objects.cone.FixedCone object at 0x7f51489f09a0>
apply_physics_material(physics_material: omni.isaac.core.materials.physics_material.PhysicsMaterial, weaker_than_descendants: bool = False)

Used to apply physics material to the held prim and optionally its descendants.

Parameters
  • physics_material (PhysicsMaterial) – physics material to be applied to the held prim. This where you want to define friction, restitution..etc. Note: if a physics material is not defined, the defaults will be used from PhysX.

  • weaker_than_descendants (bool, optional) – True if the material shouldn’t override the descendants materials, otherwise False. Defaults to False.

Example:

>>> from omni.isaac.core.materials import PhysicsMaterial
>>>
>>> # create a rigid body physical material
>>> material = PhysicsMaterial(
...     prim_path="/World/physics_material/aluminum",  # path to the material prim to create
...     dynamic_friction=0.4,
...     static_friction=1.1,
...     restitution=0.1
... )
>>> prim.apply_physics_material(material)
apply_visual_material(visual_material: omni.isaac.core.materials.visual_material.VisualMaterial, weaker_than_descendants: bool = False) None

Apply visual material to the held prim and optionally its descendants.

Parameters
  • visual_material (VisualMaterial) – visual material to be applied to the held prim. Currently supports PreviewSurface, OmniPBR and OmniGlass.

  • weaker_than_descendants (bool, optional) – True if the material shouldn’t override the descendants materials, otherwise False. Defaults to False.

Example:

>>> from omni.isaac.core.materials import OmniGlass
>>>
>>> # create a dark-red glass visual material
>>> material = OmniGlass(
...     prim_path="/World/material/glass",  # path to the material prim to create
...     ior=1.25,
...     depth=0.001,
...     thin_walled=False,
...     color=np.array([0.5, 0.0, 0.0])
... )
>>> prim.apply_visual_material(material)
property geom: pxr.UsdGeom.Gprim

Returns: UsdGeom.Gprim: USD geometry object encapsulated.

get_applied_physics_material() omni.isaac.core.materials.physics_material.PhysicsMaterial

Return the current applied physics material in case it was applied using apply_physics_material or not.

Returns

the current applied physics material.

Return type

PhysicsMaterial

Example:

>>> # given a physics material applied
>>> prim.get_applied_physics_material()
<omni.isaac.core.materials.physics_material.PhysicsMaterial object at 0x7fb66c30cd30>
get_applied_visual_material() omni.isaac.core.materials.visual_material.VisualMaterial

Return the current applied visual material in case it was applied using apply_visual_material or it’s one of the following materials that was already applied before: PreviewSurface, OmniPBR and OmniGlass.

Returns

the current applied visual material if its type is currently supported.

Return type

VisualMaterial

Example:

>>> # given a visual material applied
>>> prim.get_applied_visual_material()
<omni.isaac.core.materials.omni_glass.OmniGlass object at 0x7f36263106a0>
get_collision_approximation() str

Get the collision approximation

Approximation

Full name

Description

"none"

Triangle Mesh

The mesh geometry is used directly as a collider without any approximation

"convexDecomposition"

Convex Decomposition

A convex mesh decomposition is performed. This results in a set of convex mesh colliders

"convexHull"

Convex Hull

A convex hull of the mesh is generated and used as the collider

"boundingSphere"

Bounding Sphere

A bounding sphere is computed around the mesh and used as a collider

"boundingCube"

Bounding Cube

An optimally fitting box collider is computed around the mesh

"meshSimplification"

Mesh Simplification

A mesh simplification step is performed, resulting in a simplified triangle mesh collider

"sdf"

SDF Mesh

SDF (Signed-Distance-Field) use high-detail triangle meshes as collision shape

"sphereFill"

Sphere Approximation

A sphere mesh decomposition is performed. This results in a set of sphere colliders

Returns

approximation used for collision

Return type

str

Example:

>>> prim.get_collision_approximation()
none
get_collision_enabled() bool

Check if the Collision API is enabled

Returns

True if the Collision API is enabled. Otherwise False

Return type

bool

Example:

>>> prim.get_collision_enabled()
True
get_contact_force_matrix(dt: float = 1.0) Union[numpy.ndarray, torch.Tensor]

If the object is initialized with filter_paths_expr list, this method returns the contact forces between the prims in the view and the filter prims. i.e., a matrix of dimension (self._contact_view.num_filters, 3) where num_filters is the determined according to the filter_paths_expr parameter.

Parameters

dt (float) – time step multiplier to convert the underlying impulses to forces. If the default value is used then the forces are in fact contact impulses

Returns

Net contact forces of the prims with shape (self._geometry_prim_view._contact_view.num_filters, 3).

Return type

Union[np.ndarray, torch.Tensor]

get_contact_offset() float

Get the contact offset

Shapes whose distance is less than the sum of their contact offset values will generate contacts

Search for Advanced Collision Detection in PhysX docs for more details

Returns

contact offset of the collision shape. Default value is -inf, means default is picked by simulation.

Return type

float

Example:

>>> prim.get_contact_offset()
-inf
get_default_state() omni.isaac.core.utils.types.XFormPrimState

Get the default prim states (spatial position and orientation).

Returns

an object that contains the default state of the prim (position and orientation)

Return type

XFormPrimState

Example:

>>> state = prim.get_default_state()
>>> state
<omni.isaac.core.utils.types.XFormPrimState object at 0x7f33addda650>
>>>
>>> state.position
[-4.5299529e-08 -1.8347054e-09 -2.8610229e-08]
>>> state.orientation
[1. 0. 0. 0.]
get_height() float

Get the cone height

Returns

cone height

Return type

float

Example:

>>> prim.get_height()
1.0
get_local_pose() Tuple[numpy.ndarray, numpy.ndarray]

Get prim’s pose with respect to the local frame (the prim’s parent frame)

Returns

first index is the position in the local frame (with shape (3, )). Second index is quaternion orientation (with shape (4, )) in the local frame

Return type

Tuple[np.ndarray, np.ndarray]

Example:

>>> # if the prim is in position (1.0, 0.5, 0.0) with respect to the world frame
>>> position, orientation = prim.get_local_pose()
>>> position
[0. 0. 0.]
>>> orientation
[0. 0. 0.]
get_local_scale() numpy.ndarray

Get prim’s scale with respect to the local frame (the parent’s frame)

Returns

scale applied to the prim’s dimensions in the local frame. shape is (3, ).

Return type

np.ndarray

Example:

>>> prim.get_local_scale()
[1. 1. 1.]
get_min_torsional_patch_radius() float

Get the minimum radius of the contact patch used to apply torsional friction

Search for “Torsional Patch Radius” in PhysX docs for more details

Returns

minimum radius of the contact patch used to apply torsional friction. Allowed range [0, max_float].

Return type

float

Example:

>>> prim.get_min_torsional_patch_radius()
0.0
get_net_contact_forces(dt: float = 1.0) Union[numpy.ndarray, torch.Tensor]

If contact forces of the prims in the view are tracked, this method returns the net contact forces on prims. i.e., a matrix of dimension (1, 3)

Parameters

dt (float) – time step multiplier to convert the underlying impulses to forces. If the default value is used then the forces are in fact contact impulses

Returns

Net contact forces of the prims with shape (3).

Return type

Union[np.ndarray, torch.Tensor]

get_radius() float

Get the base radius

Returns

base radius

Return type

float

Example:

>>> prim.get_radius()
0.5
get_rest_offset() float

Get the rest offset

Two shapes will come to rest at a distance equal to the sum of their rest offset values. If the rest offset is 0, they should converge to touching exactly

Search for Advanced Collision Detection in PhysX docs for more details

Returns

rest offset of the collision shape.

Return type

float

Example:

>>> prim.get_rest_offset()
-inf
get_torsional_patch_radius() float

Get the radius of the contact patch used to apply torsional friction

Search for “Torsional Patch Radius” in PhysX docs for more details

Returns

radius of the contact patch used to apply torsional friction. Allowed range [0, max_float].

Return type

float

Example:

>>> prim.get_torsional_patch_radius()
0.0
get_visibility() bool
Returns

true if the prim is visible in stage. false otherwise.

Return type

bool

Example:

>>> # get the visible state of an visible prim on the stage
>>> prim.get_visibility()
True
get_world_pose() Tuple[numpy.ndarray, numpy.ndarray]

Get prim’s pose with respect to the world’s frame

Returns

first index is the position in the world frame (with shape (3, )). Second index is quaternion orientation (with shape (4, )) in the world frame

Return type

Tuple[np.ndarray, np.ndarray]

Example:

>>> # if the prim is in position (1.0, 0.5, 0.0) with respect to the world frame
>>> position, orientation = prim.get_world_pose()
>>> position
[1.  0.5 0. ]
>>> orientation
[1. 0. 0. 0.]
get_world_scale() numpy.ndarray

Get prim’s scale with respect to the world’s frame

Returns

scale applied to the prim’s dimensions in the world frame. shape is (3, ).

Return type

np.ndarray

Example:

>>> prim.get_world_scale()
[1. 1. 1.]
initialize(physics_sim_view=None) None

Create a physics simulation view if not passed and using PhysX tensor API

Note

If the prim has been added to the world scene (e.g., world.scene.add(prim)), it will be automatically initialized when the world is reset (e.g., world.reset()).

Parameters

physics_sim_view (omni.physics.tensors.SimulationView, optional) – current physics simulation view. Defaults to None.

Example:

>>> prim.initialize()
is_valid() bool

Check if the prim path has a valid USD Prim at it

Returns

True is the current prim path corresponds to a valid prim in stage. False otherwise.

Return type

bool

Example:

>>> # given an existing and valid prim
>>> prims.is_valid()
True
is_visual_material_applied() bool

Check if there is a visual material applied

Returns

True if there is a visual material applied. False otherwise.

Return type

bool

Example:

>>> # given a visual material applied
>>> prim.is_visual_material_applied()
True
property name: Optional[str]

Returns: str: name given to the prim when instantiating it. Otherwise None.

Used to query if the prim is a non root articulation link

Returns

True if the prim itself is a non root link

Return type

bool

Example:

>>> # for a wrapped articulation (where the root prim has the Physics Articulation Root property applied)
>>> prim.non_root_articulation_link
False
post_reset() None

Reset the prim to its default state (position and orientation).

Note

For an articulation, in addition to configuring the root prim’s default position and spatial orientation (defined via the set_default_state method), the joint’s positions, velocities, and efforts (defined via the set_joints_default_state method) are imposed

Example:

>>> prim.post_reset()
property prim: pxr.Usd.Prim

Returns: Usd.Prim: USD Prim object that this object holds.

property prim_path: str

Returns: str: prim path in the stage

set_collision_approximation(approximation_type: str) None

Set the collision approximation

Approximation

Full name

Description

"none"

Triangle Mesh

The mesh geometry is used directly as a collider without any approximation

"convexDecomposition"

Convex Decomposition

A convex mesh decomposition is performed. This results in a set of convex mesh colliders

"convexHull"

Convex Hull

A convex hull of the mesh is generated and used as the collider

"boundingSphere"

Bounding Sphere

A bounding sphere is computed around the mesh and used as a collider

"boundingCube"

Bounding Cube

An optimally fitting box collider is computed around the mesh

"meshSimplification"

Mesh Simplification

A mesh simplification step is performed, resulting in a simplified triangle mesh collider

"sdf"

SDF Mesh

SDF (Signed-Distance-Field) use high-detail triangle meshes as collision shape

"sphereFill"

Sphere Approximation

A sphere mesh decomposition is performed. This results in a set of sphere colliders

Note

Use Convex Decomposition or SDF (Signed-Distance-Field) tri-meshes to capture details better

Warning

Switching to Convex Decomposition or SDF (Signed-Distance-Field) will have a simulation performance impact due to higher computational cost

Parameters

approximation_type (str) – approximation used for collision

Example:

>>> prim.set_collision_approximation("convexDecomposition")
set_collision_enabled(enabled: bool) None

Enable/disable the Collision API

Parameters

enabled (bool) – Whether to enable or disable the Collision API

Example:

>>> # disable collisions
>>> prim.set_collision_enabled(False)
set_contact_offset(offset: float) None

Set the contact offset

Shapes whose distance is less than the sum of their contact offset values will generate contacts

Search for Advanced Collision Detection in PhysX docs for more details

Warning

The contact offset must be positive and greater than the rest offset

Parameters

offset (float) – Contact offset of a collision shape. Allowed range [maximum(0, rest_offset), 0]. Default value is -inf, means default is picked by simulation based on the shape extent.

Example:

>>> prim.set_contact_offset(0.02)
set_default_state(position: Optional[Sequence[float]] = None, orientation: Optional[Sequence[float]] = None) None

Set the default state of the prim (position and orientation), that will be used after each reset.

Parameters
  • position (Optional[Sequence[float]], optional) – position in the world frame of the prim. shape is (3, ). Defaults to None, which means left unchanged.

  • orientation (Optional[Sequence[float]], optional) – quaternion orientation in the world frame of the prim. quaternion is scalar-first (w, x, y, z). shape is (4, ). Defaults to None, which means left unchanged.

Example:

>>> # configure default state
>>> prim.set_default_state(position=np.array([1.0, 0.5, 0.0]), orientation=np.array([1, 0, 0, 0]))
>>>
>>> # set default states during post-reset
>>> prim.post_reset()
set_height(height: float) None

Set the cone height

Parameters

height (float) – cone height

Example:

>>> prim.set_height(2.0)
set_local_pose(translation: Optional[Sequence[float]] = None, orientation: Optional[Sequence[float]] = None) None

Set prim’s pose with respect to the local frame (the prim’s parent frame).

Warning

This method will change (teleport) the prim pose immediately to the indicated value

Parameters
  • translation (Optional[Sequence[float]], optional) – translation in the local frame of the prim (with respect to its parent prim). shape is (3, ). Defaults to None, which means left unchanged.

  • orientation (Optional[Sequence[float]], optional) – quaternion orientation in the local frame of the prim. quaternion is scalar-first (w, x, y, z). shape is (4, ). Defaults to None, which means left unchanged.

Hint

This method belongs to the methods used to set the prim state

Example:

>>> prim.set_local_pose(translation=np.array([1.0, 0.5, 0.0]), orientation=np.array([1., 0., 0., 0.]))
set_local_scale(scale: Optional[Sequence[float]]) None

Set prim’s scale with respect to the local frame (the prim’s parent frame).

Parameters

scale (Optional[Sequence[float]]) – scale to be applied to the prim’s dimensions. shape is (3, ). Defaults to None, which means left unchanged.

Example:

>>> # scale prim 10 times smaller
>>> prim.set_local_scale(np.array([0.1, 0.1, 0.1]))
set_min_torsional_patch_radius(radius: float) None

Set the minimum radius of the contact patch used to apply torsional friction

Search for “Torsional Patch Radius” in PhysX docs for more details

Parameters

radius (float) – minimum radius of the contact patch used to apply torsional friction. Allowed range [0, max_float].

Example:

>>> prim.set_min_torsional_patch_radius(0.05)
set_radius(radius: float) None

Set the base radius

Parameters

radius (float) – base radius

Example:

>>> prim.set_radius(1.0)
set_rest_offset(offset: float) None

Set the rest offset

Two shapes will come to rest at a distance equal to the sum of their rest offset values. If the rest offset is 0, they should converge to touching exactly

Search for Advanced Collision Detection in PhysX docs for more details

Warning

The contact offset must be positive and greater than the rest offset

Parameters

offset (float) – Rest offset of a collision shape. Allowed range [-max_float, contact_offset. Default value is -inf, means default is picked by simulation. For rigid bodies its zero.

Example:

>>> prim.set_rest_offset(0.01)
set_torsional_patch_radius(radius: float) None

Set the radius of the contact patch used to apply torsional friction

Search for “Torsional Patch Radius” in PhysX docs for more details

Parameters

radius (float) – radius of the contact patch used to apply torsional friction. Allowed range [0, max_float].

Example:

>>> prim.set_torsional_patch_radius(0.1)
set_visibility(visible: bool) None

Set the visibility of the prim in stage

Parameters

visible (bool) – flag to set the visibility of the usd prim in stage.

Example:

>>> # make prim not visible in the stage
>>> prim.set_visibility(visible=False)
set_world_pose(position: Optional[Sequence[float]] = None, orientation: Optional[Sequence[float]] = None) None

Ses prim’s pose with respect to the world’s frame

Warning

This method will change (teleport) the prim pose immediately to the indicated value

Parameters
  • position (Optional[Sequence[float]], optional) – position in the world frame of the prim. shape is (3, ). Defaults to None, which means left unchanged.

  • orientation (Optional[Sequence[float]], optional) – quaternion orientation in the world frame of the prim. quaternion is scalar-first (w, x, y, z). shape is (4, ). Defaults to None, which means left unchanged.

Hint

This method belongs to the methods used to set the prim state

Example:

>>> prim.set_world_pose(position=np.array([1.0, 0.5, 0.0]), orientation=np.array([1., 0., 0., 0.]))

Fixed Cuboid

class FixedCuboid(prim_path: str, name: str = 'fixed_cube', position: Optional[numpy.ndarray] = None, translation: Optional[numpy.ndarray] = None, orientation: Optional[numpy.ndarray] = None, scale: Optional[numpy.ndarray] = None, visible: Optional[bool] = None, color: Optional[numpy.ndarray] = None, size: Optional[float] = None, visual_material: Optional[omni.isaac.core.materials.visual_material.VisualMaterial] = None, physics_material: Optional[omni.isaac.core.materials.physics_material.PhysicsMaterial] = None)

High level wrapper to create/encapsulate a fixed cuboid

Note

Fixed cuboids (Cube shape) have collisions (Collider API) but no rigid body dynamics (Rigid Body API)

Parameters
  • prim_path (str) – prim path of the Prim to encapsulate or create

  • name (str, optional) – shortname to be used as a key by Scene class. Note: needs to be unique if the object is added to the Scene. Defaults to “fixed_cube”.

  • position (Optional[Sequence[float]], optional) – position in the world frame of the prim. shape is (3, ). Defaults to None, which means left unchanged.

  • translation (Optional[Sequence[float]], optional) – translation in the local frame of the prim (with respect to its parent prim). shape is (3, ). Defaults to None, which means left unchanged.

  • orientation (Optional[Sequence[float]], optional) – quaternion orientation in the world/ local frame of the prim (depends if translation or position is specified). quaternion is scalar-first (w, x, y, z). shape is (4, ). Defaults to None, which means left unchanged.

  • scale (Optional[Sequence[float]], optional) – local scale to be applied to the prim’s dimensions. shape is (3, ). Defaults to None, which means left unchanged.

  • visible (bool, optional) – set to false for an invisible prim in the stage while rendering. Defaults to True.

  • color (Optional[np.ndarray], optional) – color of the visual shape. Defaults to None, which means 50% gray

  • size (Optional[float], optional) – length of each cube edge. Defaults to None.

  • visual_material (Optional[VisualMaterial], optional) – visual material to be applied to the held prim. Defaults to None. If not specified, a default visual material will be added.

  • physics_material (Optional[PhysicsMaterial], optional) – physics material to be applied to the held prim. Defaults to None. If not specified, a default physics material will be added.

Example:

>>> from omni.isaac.core.objects import FixedCuboid
>>> import numpy as np
>>>
>>> # create a red fixed cube at the given path
>>> prim = FixedCuboid(prim_path="/World/Xform/Cube", color=np.array([1.0, 0.0, 0.0]))
>>> prim
<omni.isaac.core.objects.cuboid.FixedCuboid object at 0x7f7b4d91da80>
apply_physics_material(physics_material: omni.isaac.core.materials.physics_material.PhysicsMaterial, weaker_than_descendants: bool = False)

Used to apply physics material to the held prim and optionally its descendants.

Parameters
  • physics_material (PhysicsMaterial) – physics material to be applied to the held prim. This where you want to define friction, restitution..etc. Note: if a physics material is not defined, the defaults will be used from PhysX.

  • weaker_than_descendants (bool, optional) – True if the material shouldn’t override the descendants materials, otherwise False. Defaults to False.

Example:

>>> from omni.isaac.core.materials import PhysicsMaterial
>>>
>>> # create a rigid body physical material
>>> material = PhysicsMaterial(
...     prim_path="/World/physics_material/aluminum",  # path to the material prim to create
...     dynamic_friction=0.4,
...     static_friction=1.1,
...     restitution=0.1
... )
>>> prim.apply_physics_material(material)
apply_visual_material(visual_material: omni.isaac.core.materials.visual_material.VisualMaterial, weaker_than_descendants: bool = False) None

Apply visual material to the held prim and optionally its descendants.

Parameters
  • visual_material (VisualMaterial) – visual material to be applied to the held prim. Currently supports PreviewSurface, OmniPBR and OmniGlass.

  • weaker_than_descendants (bool, optional) – True if the material shouldn’t override the descendants materials, otherwise False. Defaults to False.

Example:

>>> from omni.isaac.core.materials import OmniGlass
>>>
>>> # create a dark-red glass visual material
>>> material = OmniGlass(
...     prim_path="/World/material/glass",  # path to the material prim to create
...     ior=1.25,
...     depth=0.001,
...     thin_walled=False,
...     color=np.array([0.5, 0.0, 0.0])
... )
>>> prim.apply_visual_material(material)
property geom: pxr.UsdGeom.Gprim

Returns: UsdGeom.Gprim: USD geometry object encapsulated.

get_applied_physics_material() omni.isaac.core.materials.physics_material.PhysicsMaterial

Return the current applied physics material in case it was applied using apply_physics_material or not.

Returns

the current applied physics material.

Return type

PhysicsMaterial

Example:

>>> # given a physics material applied
>>> prim.get_applied_physics_material()
<omni.isaac.core.materials.physics_material.PhysicsMaterial object at 0x7fb66c30cd30>
get_applied_visual_material() omni.isaac.core.materials.visual_material.VisualMaterial

Return the current applied visual material in case it was applied using apply_visual_material or it’s one of the following materials that was already applied before: PreviewSurface, OmniPBR and OmniGlass.

Returns

the current applied visual material if its type is currently supported.

Return type

VisualMaterial

Example:

>>> # given a visual material applied
>>> prim.get_applied_visual_material()
<omni.isaac.core.materials.omni_glass.OmniGlass object at 0x7f36263106a0>
get_collision_approximation() str

Get the collision approximation

Approximation

Full name

Description

"none"

Triangle Mesh

The mesh geometry is used directly as a collider without any approximation

"convexDecomposition"

Convex Decomposition

A convex mesh decomposition is performed. This results in a set of convex mesh colliders

"convexHull"

Convex Hull

A convex hull of the mesh is generated and used as the collider

"boundingSphere"

Bounding Sphere

A bounding sphere is computed around the mesh and used as a collider

"boundingCube"

Bounding Cube

An optimally fitting box collider is computed around the mesh

"meshSimplification"

Mesh Simplification

A mesh simplification step is performed, resulting in a simplified triangle mesh collider

"sdf"

SDF Mesh

SDF (Signed-Distance-Field) use high-detail triangle meshes as collision shape

"sphereFill"

Sphere Approximation

A sphere mesh decomposition is performed. This results in a set of sphere colliders

Returns

approximation used for collision

Return type

str

Example:

>>> prim.get_collision_approximation()
none
get_collision_enabled() bool

Check if the Collision API is enabled

Returns

True if the Collision API is enabled. Otherwise False

Return type

bool

Example:

>>> prim.get_collision_enabled()
True
get_contact_force_matrix(dt: float = 1.0) Union[numpy.ndarray, torch.Tensor]

If the object is initialized with filter_paths_expr list, this method returns the contact forces between the prims in the view and the filter prims. i.e., a matrix of dimension (self._contact_view.num_filters, 3) where num_filters is the determined according to the filter_paths_expr parameter.

Parameters

dt (float) – time step multiplier to convert the underlying impulses to forces. If the default value is used then the forces are in fact contact impulses

Returns

Net contact forces of the prims with shape (self._geometry_prim_view._contact_view.num_filters, 3).

Return type

Union[np.ndarray, torch.Tensor]

get_contact_offset() float

Get the contact offset

Shapes whose distance is less than the sum of their contact offset values will generate contacts

Search for Advanced Collision Detection in PhysX docs for more details

Returns

contact offset of the collision shape. Default value is -inf, means default is picked by simulation.

Return type

float

Example:

>>> prim.get_contact_offset()
-inf
get_default_state() omni.isaac.core.utils.types.XFormPrimState

Get the default prim states (spatial position and orientation).

Returns

an object that contains the default state of the prim (position and orientation)

Return type

XFormPrimState

Example:

>>> state = prim.get_default_state()
>>> state
<omni.isaac.core.utils.types.XFormPrimState object at 0x7f33addda650>
>>>
>>> state.position
[-4.5299529e-08 -1.8347054e-09 -2.8610229e-08]
>>> state.orientation
[1. 0. 0. 0.]
get_local_pose() Tuple[numpy.ndarray, numpy.ndarray]

Get prim’s pose with respect to the local frame (the prim’s parent frame)

Returns

first index is the position in the local frame (with shape (3, )). Second index is quaternion orientation (with shape (4, )) in the local frame

Return type

Tuple[np.ndarray, np.ndarray]

Example:

>>> # if the prim is in position (1.0, 0.5, 0.0) with respect to the world frame
>>> position, orientation = prim.get_local_pose()
>>> position
[0. 0. 0.]
>>> orientation
[0. 0. 0.]
get_local_scale() numpy.ndarray

Get prim’s scale with respect to the local frame (the parent’s frame)

Returns

scale applied to the prim’s dimensions in the local frame. shape is (3, ).

Return type

np.ndarray

Example:

>>> prim.get_local_scale()
[1. 1. 1.]
get_min_torsional_patch_radius() float

Get the minimum radius of the contact patch used to apply torsional friction

Search for “Torsional Patch Radius” in PhysX docs for more details

Returns

minimum radius of the contact patch used to apply torsional friction. Allowed range [0, max_float].

Return type

float

Example:

>>> prim.get_min_torsional_patch_radius()
0.0
get_net_contact_forces(dt: float = 1.0) Union[numpy.ndarray, torch.Tensor]

If contact forces of the prims in the view are tracked, this method returns the net contact forces on prims. i.e., a matrix of dimension (1, 3)

Parameters

dt (float) – time step multiplier to convert the underlying impulses to forces. If the default value is used then the forces are in fact contact impulses

Returns

Net contact forces of the prims with shape (3).

Return type

Union[np.ndarray, torch.Tensor]

get_rest_offset() float

Get the rest offset

Two shapes will come to rest at a distance equal to the sum of their rest offset values. If the rest offset is 0, they should converge to touching exactly

Search for Advanced Collision Detection in PhysX docs for more details

Returns

rest offset of the collision shape.

Return type

float

Example:

>>> prim.get_rest_offset()
-inf
get_size() numpy.ndarray

Get the length of each cube edge

Returns

edge length

Return type

float

Example:

>>> prim.get_size()
1.0
get_torsional_patch_radius() float

Get the radius of the contact patch used to apply torsional friction

Search for “Torsional Patch Radius” in PhysX docs for more details

Returns

radius of the contact patch used to apply torsional friction. Allowed range [0, max_float].

Return type

float

Example:

>>> prim.get_torsional_patch_radius()
0.0
get_visibility() bool
Returns

true if the prim is visible in stage. false otherwise.

Return type

bool

Example:

>>> # get the visible state of an visible prim on the stage
>>> prim.get_visibility()
True
get_world_pose() Tuple[numpy.ndarray, numpy.ndarray]

Get prim’s pose with respect to the world’s frame

Returns

first index is the position in the world frame (with shape (3, )). Second index is quaternion orientation (with shape (4, )) in the world frame

Return type

Tuple[np.ndarray, np.ndarray]

Example:

>>> # if the prim is in position (1.0, 0.5, 0.0) with respect to the world frame
>>> position, orientation = prim.get_world_pose()
>>> position
[1.  0.5 0. ]
>>> orientation
[1. 0. 0. 0.]
get_world_scale() numpy.ndarray

Get prim’s scale with respect to the world’s frame

Returns

scale applied to the prim’s dimensions in the world frame. shape is (3, ).

Return type

np.ndarray

Example:

>>> prim.get_world_scale()
[1. 1. 1.]
initialize(physics_sim_view=None) None

Create a physics simulation view if not passed and using PhysX tensor API

Note

If the prim has been added to the world scene (e.g., world.scene.add(prim)), it will be automatically initialized when the world is reset (e.g., world.reset()).

Parameters

physics_sim_view (omni.physics.tensors.SimulationView, optional) – current physics simulation view. Defaults to None.

Example:

>>> prim.initialize()
is_valid() bool

Check if the prim path has a valid USD Prim at it

Returns

True is the current prim path corresponds to a valid prim in stage. False otherwise.

Return type

bool

Example:

>>> # given an existing and valid prim
>>> prims.is_valid()
True
is_visual_material_applied() bool

Check if there is a visual material applied

Returns

True if there is a visual material applied. False otherwise.

Return type

bool

Example:

>>> # given a visual material applied
>>> prim.is_visual_material_applied()
True
property name: Optional[str]

Returns: str: name given to the prim when instantiating it. Otherwise None.

Used to query if the prim is a non root articulation link

Returns

True if the prim itself is a non root link

Return type

bool

Example:

>>> # for a wrapped articulation (where the root prim has the Physics Articulation Root property applied)
>>> prim.non_root_articulation_link
False
post_reset() None

Reset the prim to its default state (position and orientation).

Note

For an articulation, in addition to configuring the root prim’s default position and spatial orientation (defined via the set_default_state method), the joint’s positions, velocities, and efforts (defined via the set_joints_default_state method) are imposed

Example:

>>> prim.post_reset()
property prim: pxr.Usd.Prim

Returns: Usd.Prim: USD Prim object that this object holds.

property prim_path: str

Returns: str: prim path in the stage

set_collision_approximation(approximation_type: str) None

Set the collision approximation

Approximation

Full name

Description

"none"

Triangle Mesh

The mesh geometry is used directly as a collider without any approximation

"convexDecomposition"

Convex Decomposition

A convex mesh decomposition is performed. This results in a set of convex mesh colliders

"convexHull"

Convex Hull

A convex hull of the mesh is generated and used as the collider

"boundingSphere"

Bounding Sphere

A bounding sphere is computed around the mesh and used as a collider

"boundingCube"

Bounding Cube

An optimally fitting box collider is computed around the mesh

"meshSimplification"

Mesh Simplification

A mesh simplification step is performed, resulting in a simplified triangle mesh collider

"sdf"

SDF Mesh

SDF (Signed-Distance-Field) use high-detail triangle meshes as collision shape

"sphereFill"

Sphere Approximation

A sphere mesh decomposition is performed. This results in a set of sphere colliders

Note

Use Convex Decomposition or SDF (Signed-Distance-Field) tri-meshes to capture details better

Warning

Switching to Convex Decomposition or SDF (Signed-Distance-Field) will have a simulation performance impact due to higher computational cost

Parameters

approximation_type (str) – approximation used for collision

Example:

>>> prim.set_collision_approximation("convexDecomposition")
set_collision_enabled(enabled: bool) None

Enable/disable the Collision API

Parameters

enabled (bool) – Whether to enable or disable the Collision API

Example:

>>> # disable collisions
>>> prim.set_collision_enabled(False)
set_contact_offset(offset: float) None

Set the contact offset

Shapes whose distance is less than the sum of their contact offset values will generate contacts

Search for Advanced Collision Detection in PhysX docs for more details

Warning

The contact offset must be positive and greater than the rest offset

Parameters

offset (float) – Contact offset of a collision shape. Allowed range [maximum(0, rest_offset), 0]. Default value is -inf, means default is picked by simulation based on the shape extent.

Example:

>>> prim.set_contact_offset(0.02)
set_default_state(position: Optional[Sequence[float]] = None, orientation: Optional[Sequence[float]] = None) None

Set the default state of the prim (position and orientation), that will be used after each reset.

Parameters
  • position (Optional[Sequence[float]], optional) – position in the world frame of the prim. shape is (3, ). Defaults to None, which means left unchanged.

  • orientation (Optional[Sequence[float]], optional) – quaternion orientation in the world frame of the prim. quaternion is scalar-first (w, x, y, z). shape is (4, ). Defaults to None, which means left unchanged.

Example:

>>> # configure default state
>>> prim.set_default_state(position=np.array([1.0, 0.5, 0.0]), orientation=np.array([1, 0, 0, 0]))
>>>
>>> # set default states during post-reset
>>> prim.post_reset()
set_local_pose(translation: Optional[Sequence[float]] = None, orientation: Optional[Sequence[float]] = None) None

Set prim’s pose with respect to the local frame (the prim’s parent frame).

Warning

This method will change (teleport) the prim pose immediately to the indicated value

Parameters
  • translation (Optional[Sequence[float]], optional) – translation in the local frame of the prim (with respect to its parent prim). shape is (3, ). Defaults to None, which means left unchanged.

  • orientation (Optional[Sequence[float]], optional) – quaternion orientation in the local frame of the prim. quaternion is scalar-first (w, x, y, z). shape is (4, ). Defaults to None, which means left unchanged.

Hint

This method belongs to the methods used to set the prim state

Example:

>>> prim.set_local_pose(translation=np.array([1.0, 0.5, 0.0]), orientation=np.array([1., 0., 0., 0.]))
set_local_scale(scale: Optional[Sequence[float]]) None

Set prim’s scale with respect to the local frame (the prim’s parent frame).

Parameters

scale (Optional[Sequence[float]]) – scale to be applied to the prim’s dimensions. shape is (3, ). Defaults to None, which means left unchanged.

Example:

>>> # scale prim 10 times smaller
>>> prim.set_local_scale(np.array([0.1, 0.1, 0.1]))
set_min_torsional_patch_radius(radius: float) None

Set the minimum radius of the contact patch used to apply torsional friction

Search for “Torsional Patch Radius” in PhysX docs for more details

Parameters

radius (float) – minimum radius of the contact patch used to apply torsional friction. Allowed range [0, max_float].

Example:

>>> prim.set_min_torsional_patch_radius(0.05)
set_rest_offset(offset: float) None

Set the rest offset

Two shapes will come to rest at a distance equal to the sum of their rest offset values. If the rest offset is 0, they should converge to touching exactly

Search for Advanced Collision Detection in PhysX docs for more details

Warning

The contact offset must be positive and greater than the rest offset

Parameters

offset (float) – Rest offset of a collision shape. Allowed range [-max_float, contact_offset. Default value is -inf, means default is picked by simulation. For rigid bodies its zero.

Example:

>>> prim.set_rest_offset(0.01)
set_size(size: float) None

Set the length of each cube edge

Parameters

size (float) – edge length

Example:

>>> prim.set_size(2.0)
set_torsional_patch_radius(radius: float) None

Set the radius of the contact patch used to apply torsional friction

Search for “Torsional Patch Radius” in PhysX docs for more details

Parameters

radius (float) – radius of the contact patch used to apply torsional friction. Allowed range [0, max_float].

Example:

>>> prim.set_torsional_patch_radius(0.1)
set_visibility(visible: bool) None

Set the visibility of the prim in stage

Parameters

visible (bool) – flag to set the visibility of the usd prim in stage.

Example:

>>> # make prim not visible in the stage
>>> prim.set_visibility(visible=False)
set_world_pose(position: Optional[Sequence[float]] = None, orientation: Optional[Sequence[float]] = None) None

Ses prim’s pose with respect to the world’s frame

Warning

This method will change (teleport) the prim pose immediately to the indicated value

Parameters
  • position (Optional[Sequence[float]], optional) – position in the world frame of the prim. shape is (3, ). Defaults to None, which means left unchanged.

  • orientation (Optional[Sequence[float]], optional) – quaternion orientation in the world frame of the prim. quaternion is scalar-first (w, x, y, z). shape is (4, ). Defaults to None, which means left unchanged.

Hint

This method belongs to the methods used to set the prim state

Example:

>>> prim.set_world_pose(position=np.array([1.0, 0.5, 0.0]), orientation=np.array([1., 0., 0., 0.]))

Fixed Cylinder

class FixedCylinder(prim_path: str, name: str = 'fixed_cylinder', position: Optional[numpy.ndarray] = None, translation: Optional[numpy.ndarray] = None, orientation: Optional[numpy.ndarray] = None, scale: Optional[numpy.ndarray] = None, visible: Optional[bool] = None, color: Optional[numpy.ndarray] = None, radius: Optional[numpy.ndarray] = None, height: Optional[float] = None, visual_material: Optional[omni.isaac.core.materials.visual_material.VisualMaterial] = None, physics_material: Optional[omni.isaac.core.materials.physics_material.PhysicsMaterial] = None)

High level wrapper to create/encapsulate a fixed cylinder

Note

Fixed cylinders (Cylinder shape) have collisions (Collider API) but no rigid body dynamics (Rigid Body API)

Parameters
  • prim_path (str) – prim path of the Prim to encapsulate or create

  • name (str, optional) – shortname to be used as a key by Scene class. Note: needs to be unique if the object is added to the Scene. Defaults to “fixed_cylinder”.

  • position (Optional[Sequence[float]], optional) – position in the world frame of the prim. shape is (3, ). Defaults to None, which means left unchanged.

  • translation (Optional[Sequence[float]], optional) – translation in the local frame of the prim (with respect to its parent prim). shape is (3, ). Defaults to None, which means left unchanged.

  • orientation (Optional[Sequence[float]], optional) – quaternion orientation in the world/ local frame of the prim (depends if translation or position is specified). quaternion is scalar-first (w, x, y, z). shape is (4, ). Defaults to None, which means left unchanged.

  • scale (Optional[Sequence[float]], optional) – local scale to be applied to the prim’s dimensions. shape is (3, ). Defaults to None, which means left unchanged.

  • visible (bool, optional) – set to false for an invisible prim in the stage while rendering. Defaults to True.

  • color (Optional[np.ndarray], optional) – color of the visual shape. Defaults to None, which means 50% gray

  • radius (Optional[float], optional) – base radius. Defaults to None.

  • height (Optional[float], optional) – cylinder height. Defaults to None.

  • visual_material (Optional[VisualMaterial], optional) – visual material to be applied to the held prim. Defaults to None. If not specified, a default visual material will be added.

  • physics_material (Optional[PhysicsMaterial], optional) – physics material to be applied to the held prim. Defaults to None. If not specified, a default physics material will be added.

Example:

>>> from omni.isaac.core.objects import FixedCylinder
>>> import numpy as np
>>>
>>> # create a red fixed cylinder at the given path
>>> prim = FixedCylinder(
...     prim_path="/World/Xform/Cylinder",
...     radius=0.5,
...     height=1.0,
...     color=np.array([1.0, 0.0, 0.0])
... )
>>> print(prim)
<omni.isaac.core.objects.cylinder.FixedCylinder object at 0x7f4f24144f40>
apply_physics_material(physics_material: omni.isaac.core.materials.physics_material.PhysicsMaterial, weaker_than_descendants: bool = False)

Used to apply physics material to the held prim and optionally its descendants.

Parameters
  • physics_material (PhysicsMaterial) – physics material to be applied to the held prim. This where you want to define friction, restitution..etc. Note: if a physics material is not defined, the defaults will be used from PhysX.

  • weaker_than_descendants (bool, optional) – True if the material shouldn’t override the descendants materials, otherwise False. Defaults to False.

Example:

>>> from omni.isaac.core.materials import PhysicsMaterial
>>>
>>> # create a rigid body physical material
>>> material = PhysicsMaterial(
...     prim_path="/World/physics_material/aluminum",  # path to the material prim to create
...     dynamic_friction=0.4,
...     static_friction=1.1,
...     restitution=0.1
... )
>>> prim.apply_physics_material(material)
apply_visual_material(visual_material: omni.isaac.core.materials.visual_material.VisualMaterial, weaker_than_descendants: bool = False) None

Apply visual material to the held prim and optionally its descendants.

Parameters
  • visual_material (VisualMaterial) – visual material to be applied to the held prim. Currently supports PreviewSurface, OmniPBR and OmniGlass.

  • weaker_than_descendants (bool, optional) – True if the material shouldn’t override the descendants materials, otherwise False. Defaults to False.

Example:

>>> from omni.isaac.core.materials import OmniGlass
>>>
>>> # create a dark-red glass visual material
>>> material = OmniGlass(
...     prim_path="/World/material/glass",  # path to the material prim to create
...     ior=1.25,
...     depth=0.001,
...     thin_walled=False,
...     color=np.array([0.5, 0.0, 0.0])
... )
>>> prim.apply_visual_material(material)
property geom: pxr.UsdGeom.Gprim

Returns: UsdGeom.Gprim: USD geometry object encapsulated.

get_applied_physics_material() omni.isaac.core.materials.physics_material.PhysicsMaterial

Return the current applied physics material in case it was applied using apply_physics_material or not.

Returns

the current applied physics material.

Return type

PhysicsMaterial

Example:

>>> # given a physics material applied
>>> prim.get_applied_physics_material()
<omni.isaac.core.materials.physics_material.PhysicsMaterial object at 0x7fb66c30cd30>
get_applied_visual_material() omni.isaac.core.materials.visual_material.VisualMaterial

Return the current applied visual material in case it was applied using apply_visual_material or it’s one of the following materials that was already applied before: PreviewSurface, OmniPBR and OmniGlass.

Returns

the current applied visual material if its type is currently supported.

Return type

VisualMaterial

Example:

>>> # given a visual material applied
>>> prim.get_applied_visual_material()
<omni.isaac.core.materials.omni_glass.OmniGlass object at 0x7f36263106a0>
get_collision_approximation() str

Get the collision approximation

Approximation

Full name

Description

"none"

Triangle Mesh

The mesh geometry is used directly as a collider without any approximation

"convexDecomposition"

Convex Decomposition

A convex mesh decomposition is performed. This results in a set of convex mesh colliders

"convexHull"

Convex Hull

A convex hull of the mesh is generated and used as the collider

"boundingSphere"

Bounding Sphere

A bounding sphere is computed around the mesh and used as a collider

"boundingCube"

Bounding Cube

An optimally fitting box collider is computed around the mesh

"meshSimplification"

Mesh Simplification

A mesh simplification step is performed, resulting in a simplified triangle mesh collider

"sdf"

SDF Mesh

SDF (Signed-Distance-Field) use high-detail triangle meshes as collision shape

"sphereFill"

Sphere Approximation

A sphere mesh decomposition is performed. This results in a set of sphere colliders

Returns

approximation used for collision

Return type

str

Example:

>>> prim.get_collision_approximation()
none
get_collision_enabled() bool

Check if the Collision API is enabled

Returns

True if the Collision API is enabled. Otherwise False

Return type

bool

Example:

>>> prim.get_collision_enabled()
True
get_contact_force_matrix(dt: float = 1.0) Union[numpy.ndarray, torch.Tensor]

If the object is initialized with filter_paths_expr list, this method returns the contact forces between the prims in the view and the filter prims. i.e., a matrix of dimension (self._contact_view.num_filters, 3) where num_filters is the determined according to the filter_paths_expr parameter.

Parameters

dt (float) – time step multiplier to convert the underlying impulses to forces. If the default value is used then the forces are in fact contact impulses

Returns

Net contact forces of the prims with shape (self._geometry_prim_view._contact_view.num_filters, 3).

Return type

Union[np.ndarray, torch.Tensor]

get_contact_offset() float

Get the contact offset

Shapes whose distance is less than the sum of their contact offset values will generate contacts

Search for Advanced Collision Detection in PhysX docs for more details

Returns

contact offset of the collision shape. Default value is -inf, means default is picked by simulation.

Return type

float

Example:

>>> prim.get_contact_offset()
-inf
get_default_state() omni.isaac.core.utils.types.XFormPrimState

Get the default prim states (spatial position and orientation).

Returns

an object that contains the default state of the prim (position and orientation)

Return type

XFormPrimState

Example:

>>> state = prim.get_default_state()
>>> state
<omni.isaac.core.utils.types.XFormPrimState object at 0x7f33addda650>
>>>
>>> state.position
[-4.5299529e-08 -1.8347054e-09 -2.8610229e-08]
>>> state.orientation
[1. 0. 0. 0.]
get_height() float

Get the cylinder height

Returns

cylinder height

Return type

float

Example:

>>> prim.get_height()
1.0
get_local_pose() Tuple[numpy.ndarray, numpy.ndarray]

Get prim’s pose with respect to the local frame (the prim’s parent frame)

Returns

first index is the position in the local frame (with shape (3, )). Second index is quaternion orientation (with shape (4, )) in the local frame

Return type

Tuple[np.ndarray, np.ndarray]

Example:

>>> # if the prim is in position (1.0, 0.5, 0.0) with respect to the world frame
>>> position, orientation = prim.get_local_pose()
>>> position
[0. 0. 0.]
>>> orientation
[0. 0. 0.]
get_local_scale() numpy.ndarray

Get prim’s scale with respect to the local frame (the parent’s frame)

Returns

scale applied to the prim’s dimensions in the local frame. shape is (3, ).

Return type

np.ndarray

Example:

>>> prim.get_local_scale()
[1. 1. 1.]
get_min_torsional_patch_radius() float

Get the minimum radius of the contact patch used to apply torsional friction

Search for “Torsional Patch Radius” in PhysX docs for more details

Returns

minimum radius of the contact patch used to apply torsional friction. Allowed range [0, max_float].

Return type

float

Example:

>>> prim.get_min_torsional_patch_radius()
0.0
get_net_contact_forces(dt: float = 1.0) Union[numpy.ndarray, torch.Tensor]

If contact forces of the prims in the view are tracked, this method returns the net contact forces on prims. i.e., a matrix of dimension (1, 3)

Parameters

dt (float) – time step multiplier to convert the underlying impulses to forces. If the default value is used then the forces are in fact contact impulses

Returns

Net contact forces of the prims with shape (3).

Return type

Union[np.ndarray, torch.Tensor]

get_radius() float

Get the base radius

Returns

base radius

Return type

float

Example:

>>> prim.get_radius()
0.5
get_rest_offset() float

Get the rest offset

Two shapes will come to rest at a distance equal to the sum of their rest offset values. If the rest offset is 0, they should converge to touching exactly

Search for Advanced Collision Detection in PhysX docs for more details

Returns

rest offset of the collision shape.

Return type

float

Example:

>>> prim.get_rest_offset()
-inf
get_torsional_patch_radius() float

Get the radius of the contact patch used to apply torsional friction

Search for “Torsional Patch Radius” in PhysX docs for more details

Returns

radius of the contact patch used to apply torsional friction. Allowed range [0, max_float].

Return type

float

Example:

>>> prim.get_torsional_patch_radius()
0.0
get_visibility() bool
Returns

true if the prim is visible in stage. false otherwise.

Return type

bool

Example:

>>> # get the visible state of an visible prim on the stage
>>> prim.get_visibility()
True
get_world_pose() Tuple[numpy.ndarray, numpy.ndarray]

Get prim’s pose with respect to the world’s frame

Returns

first index is the position in the world frame (with shape (3, )). Second index is quaternion orientation (with shape (4, )) in the world frame

Return type

Tuple[np.ndarray, np.ndarray]

Example:

>>> # if the prim is in position (1.0, 0.5, 0.0) with respect to the world frame
>>> position, orientation = prim.get_world_pose()
>>> position
[1.  0.5 0. ]
>>> orientation
[1. 0. 0. 0.]
get_world_scale() numpy.ndarray

Get prim’s scale with respect to the world’s frame

Returns

scale applied to the prim’s dimensions in the world frame. shape is (3, ).

Return type

np.ndarray

Example:

>>> prim.get_world_scale()
[1. 1. 1.]
initialize(physics_sim_view=None) None

Create a physics simulation view if not passed and using PhysX tensor API

Note

If the prim has been added to the world scene (e.g., world.scene.add(prim)), it will be automatically initialized when the world is reset (e.g., world.reset()).

Parameters

physics_sim_view (omni.physics.tensors.SimulationView, optional) – current physics simulation view. Defaults to None.

Example:

>>> prim.initialize()
is_valid() bool

Check if the prim path has a valid USD Prim at it

Returns

True is the current prim path corresponds to a valid prim in stage. False otherwise.

Return type

bool

Example:

>>> # given an existing and valid prim
>>> prims.is_valid()
True
is_visual_material_applied() bool

Check if there is a visual material applied

Returns

True if there is a visual material applied. False otherwise.

Return type

bool

Example:

>>> # given a visual material applied
>>> prim.is_visual_material_applied()
True
property name: Optional[str]

Returns: str: name given to the prim when instantiating it. Otherwise None.

Used to query if the prim is a non root articulation link

Returns

True if the prim itself is a non root link

Return type

bool

Example:

>>> # for a wrapped articulation (where the root prim has the Physics Articulation Root property applied)
>>> prim.non_root_articulation_link
False
post_reset() None

Reset the prim to its default state (position and orientation).

Note

For an articulation, in addition to configuring the root prim’s default position and spatial orientation (defined via the set_default_state method), the joint’s positions, velocities, and efforts (defined via the set_joints_default_state method) are imposed

Example:

>>> prim.post_reset()
property prim: pxr.Usd.Prim

Returns: Usd.Prim: USD Prim object that this object holds.

property prim_path: str

Returns: str: prim path in the stage

set_collision_approximation(approximation_type: str) None

Set the collision approximation

Approximation

Full name

Description

"none"

Triangle Mesh

The mesh geometry is used directly as a collider without any approximation

"convexDecomposition"

Convex Decomposition

A convex mesh decomposition is performed. This results in a set of convex mesh colliders

"convexHull"

Convex Hull

A convex hull of the mesh is generated and used as the collider

"boundingSphere"

Bounding Sphere

A bounding sphere is computed around the mesh and used as a collider

"boundingCube"

Bounding Cube

An optimally fitting box collider is computed around the mesh

"meshSimplification"

Mesh Simplification

A mesh simplification step is performed, resulting in a simplified triangle mesh collider

"sdf"

SDF Mesh

SDF (Signed-Distance-Field) use high-detail triangle meshes as collision shape

"sphereFill"

Sphere Approximation

A sphere mesh decomposition is performed. This results in a set of sphere colliders

Note

Use Convex Decomposition or SDF (Signed-Distance-Field) tri-meshes to capture details better

Warning

Switching to Convex Decomposition or SDF (Signed-Distance-Field) will have a simulation performance impact due to higher computational cost

Parameters

approximation_type (str) – approximation used for collision

Example:

>>> prim.set_collision_approximation("convexDecomposition")
set_collision_enabled(enabled: bool) None

Enable/disable the Collision API

Parameters

enabled (bool) – Whether to enable or disable the Collision API

Example:

>>> # disable collisions
>>> prim.set_collision_enabled(False)
set_contact_offset(offset: float) None

Set the contact offset

Shapes whose distance is less than the sum of their contact offset values will generate contacts

Search for Advanced Collision Detection in PhysX docs for more details

Warning

The contact offset must be positive and greater than the rest offset

Parameters

offset (float) – Contact offset of a collision shape. Allowed range [maximum(0, rest_offset), 0]. Default value is -inf, means default is picked by simulation based on the shape extent.

Example:

>>> prim.set_contact_offset(0.02)
set_default_state(position: Optional[Sequence[float]] = None, orientation: Optional[Sequence[float]] = None) None

Set the default state of the prim (position and orientation), that will be used after each reset.

Parameters
  • position (Optional[Sequence[float]], optional) – position in the world frame of the prim. shape is (3, ). Defaults to None, which means left unchanged.

  • orientation (Optional[Sequence[float]], optional) – quaternion orientation in the world frame of the prim. quaternion is scalar-first (w, x, y, z). shape is (4, ). Defaults to None, which means left unchanged.

Example:

>>> # configure default state
>>> prim.set_default_state(position=np.array([1.0, 0.5, 0.0]), orientation=np.array([1, 0, 0, 0]))
>>>
>>> # set default states during post-reset
>>> prim.post_reset()
set_height(height: float) None

Set the cylinder height

Parameters

height (float) – cylinder height

Example:

>>> prim.set_height(2.0)
set_local_pose(translation: Optional[Sequence[float]] = None, orientation: Optional[Sequence[float]] = None) None

Set prim’s pose with respect to the local frame (the prim’s parent frame).

Warning

This method will change (teleport) the prim pose immediately to the indicated value

Parameters
  • translation (Optional[Sequence[float]], optional) – translation in the local frame of the prim (with respect to its parent prim). shape is (3, ). Defaults to None, which means left unchanged.

  • orientation (Optional[Sequence[float]], optional) – quaternion orientation in the local frame of the prim. quaternion is scalar-first (w, x, y, z). shape is (4, ). Defaults to None, which means left unchanged.

Hint

This method belongs to the methods used to set the prim state

Example:

>>> prim.set_local_pose(translation=np.array([1.0, 0.5, 0.0]), orientation=np.array([1., 0., 0., 0.]))
set_local_scale(scale: Optional[Sequence[float]]) None

Set prim’s scale with respect to the local frame (the prim’s parent frame).

Parameters

scale (Optional[Sequence[float]]) – scale to be applied to the prim’s dimensions. shape is (3, ). Defaults to None, which means left unchanged.

Example:

>>> # scale prim 10 times smaller
>>> prim.set_local_scale(np.array([0.1, 0.1, 0.1]))
set_min_torsional_patch_radius(radius: float) None

Set the minimum radius of the contact patch used to apply torsional friction

Search for “Torsional Patch Radius” in PhysX docs for more details

Parameters

radius (float) – minimum radius of the contact patch used to apply torsional friction. Allowed range [0, max_float].

Example:

>>> prim.set_min_torsional_patch_radius(0.05)
set_radius(radius: float) None

Set the base radius

Parameters

radius (float) – base radius

Example:

>>> prim.set_radius(1.0)
set_rest_offset(offset: float) None

Set the rest offset

Two shapes will come to rest at a distance equal to the sum of their rest offset values. If the rest offset is 0, they should converge to touching exactly

Search for Advanced Collision Detection in PhysX docs for more details

Warning

The contact offset must be positive and greater than the rest offset

Parameters

offset (float) – Rest offset of a collision shape. Allowed range [-max_float, contact_offset. Default value is -inf, means default is picked by simulation. For rigid bodies its zero.

Example:

>>> prim.set_rest_offset(0.01)
set_torsional_patch_radius(radius: float) None

Set the radius of the contact patch used to apply torsional friction

Search for “Torsional Patch Radius” in PhysX docs for more details

Parameters

radius (float) – radius of the contact patch used to apply torsional friction. Allowed range [0, max_float].

Example:

>>> prim.set_torsional_patch_radius(0.1)
set_visibility(visible: bool) None

Set the visibility of the prim in stage

Parameters

visible (bool) – flag to set the visibility of the usd prim in stage.

Example:

>>> # make prim not visible in the stage
>>> prim.set_visibility(visible=False)
set_world_pose(position: Optional[Sequence[float]] = None, orientation: Optional[Sequence[float]] = None) None

Ses prim’s pose with respect to the world’s frame

Warning

This method will change (teleport) the prim pose immediately to the indicated value

Parameters
  • position (Optional[Sequence[float]], optional) – position in the world frame of the prim. shape is (3, ). Defaults to None, which means left unchanged.

  • orientation (Optional[Sequence[float]], optional) – quaternion orientation in the world frame of the prim. quaternion is scalar-first (w, x, y, z). shape is (4, ). Defaults to None, which means left unchanged.

Hint

This method belongs to the methods used to set the prim state

Example:

>>> prim.set_world_pose(position=np.array([1.0, 0.5, 0.0]), orientation=np.array([1., 0., 0., 0.]))

Fixed Sphere

class FixedSphere(prim_path: str, name: str = 'fixed_sphere', position: Optional[numpy.ndarray] = None, translation: Optional[numpy.ndarray] = None, orientation: Optional[numpy.ndarray] = None, scale: Optional[numpy.ndarray] = None, visible: Optional[bool] = None, color: Optional[numpy.ndarray] = None, radius: Optional[numpy.ndarray] = None, visual_material: Optional[omni.isaac.core.materials.visual_material.VisualMaterial] = None, physics_material: Optional[omni.isaac.core.materials.physics_material.PhysicsMaterial] = None)

High level wrapper to create/encapsulate a fixed sphere

Note

Fixed spheres (Sphere shape) have collisions (Collider API) but no rigid body dynamics (Rigid Body API)

Parameters
  • prim_path (str) – prim path of the Prim to encapsulate or create

  • name (str, optional) – shortname to be used as a key by Scene class. Note: needs to be unique if the object is added to the Scene. Defaults to “fixed_sphere”.

  • position (Optional[Sequence[float]], optional) – position in the world frame of the prim. shape is (3, ). Defaults to None, which means left unchanged.

  • translation (Optional[Sequence[float]], optional) – translation in the local frame of the prim (with respect to its parent prim). shape is (3, ). Defaults to None, which means left unchanged.

  • orientation (Optional[Sequence[float]], optional) – quaternion orientation in the world/ local frame of the prim (depends if translation or position is specified). quaternion is scalar-first (w, x, y, z). shape is (4, ). Defaults to None, which means left unchanged.

  • scale (Optional[Sequence[float]], optional) – local scale to be applied to the prim’s dimensions. shape is (3, ). Defaults to None, which means left unchanged.

  • visible (bool, optional) – set to false for an invisible prim in the stage while rendering. Defaults to True.

  • color (Optional[np.ndarray], optional) – color of the visual shape. Defaults to None, which means 50% gray

  • radius (Optional[float], optional) – sphere radius. Defaults to None.

  • visual_material (Optional[VisualMaterial], optional) – visual material to be applied to the held prim. Defaults to None. If not specified, a default visual material will be added.

  • physics_material (Optional[PhysicsMaterial], optional) – physics material to be applied to the held prim. Defaults to None. If not specified, a default physics material will be added.

Example:

>>> from omni.isaac.core.objects import FixedSphere
>>> import numpy as np
>>>
>>> # create a red fixed sphere at the given path
>>> prim = FixedSphere(prim_path="/World/Xform/Sphere", color=np.array([1.0, 0.0, 0.0]))
>>> prim
<omni.isaac.core.objects.sphere.FixedSphere object at 0x7f4e433f2140>
apply_physics_material(physics_material: omni.isaac.core.materials.physics_material.PhysicsMaterial, weaker_than_descendants: bool = False)

Used to apply physics material to the held prim and optionally its descendants.

Parameters
  • physics_material (PhysicsMaterial) – physics material to be applied to the held prim. This where you want to define friction, restitution..etc. Note: if a physics material is not defined, the defaults will be used from PhysX.

  • weaker_than_descendants (bool, optional) – True if the material shouldn’t override the descendants materials, otherwise False. Defaults to False.

Example:

>>> from omni.isaac.core.materials import PhysicsMaterial
>>>
>>> # create a rigid body physical material
>>> material = PhysicsMaterial(
...     prim_path="/World/physics_material/aluminum",  # path to the material prim to create
...     dynamic_friction=0.4,
...     static_friction=1.1,
...     restitution=0.1
... )
>>> prim.apply_physics_material(material)
apply_visual_material(visual_material: omni.isaac.core.materials.visual_material.VisualMaterial, weaker_than_descendants: bool = False) None

Apply visual material to the held prim and optionally its descendants.

Parameters
  • visual_material (VisualMaterial) – visual material to be applied to the held prim. Currently supports PreviewSurface, OmniPBR and OmniGlass.

  • weaker_than_descendants (bool, optional) – True if the material shouldn’t override the descendants materials, otherwise False. Defaults to False.

Example:

>>> from omni.isaac.core.materials import OmniGlass
>>>
>>> # create a dark-red glass visual material
>>> material = OmniGlass(
...     prim_path="/World/material/glass",  # path to the material prim to create
...     ior=1.25,
...     depth=0.001,
...     thin_walled=False,
...     color=np.array([0.5, 0.0, 0.0])
... )
>>> prim.apply_visual_material(material)
property geom: pxr.UsdGeom.Gprim

Returns: UsdGeom.Gprim: USD geometry object encapsulated.

get_applied_physics_material() omni.isaac.core.materials.physics_material.PhysicsMaterial

Return the current applied physics material in case it was applied using apply_physics_material or not.

Returns

the current applied physics material.

Return type

PhysicsMaterial

Example:

>>> # given a physics material applied
>>> prim.get_applied_physics_material()
<omni.isaac.core.materials.physics_material.PhysicsMaterial object at 0x7fb66c30cd30>
get_applied_visual_material() omni.isaac.core.materials.visual_material.VisualMaterial

Return the current applied visual material in case it was applied using apply_visual_material or it’s one of the following materials that was already applied before: PreviewSurface, OmniPBR and OmniGlass.

Returns

the current applied visual material if its type is currently supported.

Return type

VisualMaterial

Example:

>>> # given a visual material applied
>>> prim.get_applied_visual_material()
<omni.isaac.core.materials.omni_glass.OmniGlass object at 0x7f36263106a0>
get_collision_approximation() str

Get the collision approximation

Approximation

Full name

Description

"none"

Triangle Mesh

The mesh geometry is used directly as a collider without any approximation

"convexDecomposition"

Convex Decomposition

A convex mesh decomposition is performed. This results in a set of convex mesh colliders

"convexHull"

Convex Hull

A convex hull of the mesh is generated and used as the collider

"boundingSphere"

Bounding Sphere

A bounding sphere is computed around the mesh and used as a collider

"boundingCube"

Bounding Cube

An optimally fitting box collider is computed around the mesh

"meshSimplification"

Mesh Simplification

A mesh simplification step is performed, resulting in a simplified triangle mesh collider

"sdf"

SDF Mesh

SDF (Signed-Distance-Field) use high-detail triangle meshes as collision shape

"sphereFill"

Sphere Approximation

A sphere mesh decomposition is performed. This results in a set of sphere colliders

Returns

approximation used for collision

Return type

str

Example:

>>> prim.get_collision_approximation()
none
get_collision_enabled() bool

Check if the Collision API is enabled

Returns

True if the Collision API is enabled. Otherwise False

Return type

bool

Example:

>>> prim.get_collision_enabled()
True
get_contact_force_matrix(dt: float = 1.0) Union[numpy.ndarray, torch.Tensor]

If the object is initialized with filter_paths_expr list, this method returns the contact forces between the prims in the view and the filter prims. i.e., a matrix of dimension (self._contact_view.num_filters, 3) where num_filters is the determined according to the filter_paths_expr parameter.

Parameters

dt (float) – time step multiplier to convert the underlying impulses to forces. If the default value is used then the forces are in fact contact impulses

Returns

Net contact forces of the prims with shape (self._geometry_prim_view._contact_view.num_filters, 3).

Return type

Union[np.ndarray, torch.Tensor]

get_contact_offset() float

Get the contact offset

Shapes whose distance is less than the sum of their contact offset values will generate contacts

Search for Advanced Collision Detection in PhysX docs for more details

Returns

contact offset of the collision shape. Default value is -inf, means default is picked by simulation.

Return type

float

Example:

>>> prim.get_contact_offset()
-inf
get_default_state() omni.isaac.core.utils.types.XFormPrimState

Get the default prim states (spatial position and orientation).

Returns

an object that contains the default state of the prim (position and orientation)

Return type

XFormPrimState

Example:

>>> state = prim.get_default_state()
>>> state
<omni.isaac.core.utils.types.XFormPrimState object at 0x7f33addda650>
>>>
>>> state.position
[-4.5299529e-08 -1.8347054e-09 -2.8610229e-08]
>>> state.orientation
[1. 0. 0. 0.]
get_local_pose() Tuple[numpy.ndarray, numpy.ndarray]

Get prim’s pose with respect to the local frame (the prim’s parent frame)

Returns

first index is the position in the local frame (with shape (3, )). Second index is quaternion orientation (with shape (4, )) in the local frame

Return type

Tuple[np.ndarray, np.ndarray]

Example:

>>> # if the prim is in position (1.0, 0.5, 0.0) with respect to the world frame
>>> position, orientation = prim.get_local_pose()
>>> position
[0. 0. 0.]
>>> orientation
[0. 0. 0.]
get_local_scale() numpy.ndarray

Get prim’s scale with respect to the local frame (the parent’s frame)

Returns

scale applied to the prim’s dimensions in the local frame. shape is (3, ).

Return type

np.ndarray

Example:

>>> prim.get_local_scale()
[1. 1. 1.]
get_min_torsional_patch_radius() float

Get the minimum radius of the contact patch used to apply torsional friction

Search for “Torsional Patch Radius” in PhysX docs for more details

Returns

minimum radius of the contact patch used to apply torsional friction. Allowed range [0, max_float].

Return type

float

Example:

>>> prim.get_min_torsional_patch_radius()
0.0
get_net_contact_forces(dt: float = 1.0) Union[numpy.ndarray, torch.Tensor]

If contact forces of the prims in the view are tracked, this method returns the net contact forces on prims. i.e., a matrix of dimension (1, 3)

Parameters

dt (float) – time step multiplier to convert the underlying impulses to forces. If the default value is used then the forces are in fact contact impulses

Returns

Net contact forces of the prims with shape (3).

Return type

Union[np.ndarray, torch.Tensor]

get_radius() float

Get the sphere radius

Returns

sphere radius

Return type

float

Example:

>>> prim.get_radius()
1.0
get_rest_offset() float

Get the rest offset

Two shapes will come to rest at a distance equal to the sum of their rest offset values. If the rest offset is 0, they should converge to touching exactly

Search for Advanced Collision Detection in PhysX docs for more details

Returns

rest offset of the collision shape.

Return type

float

Example:

>>> prim.get_rest_offset()
-inf
get_torsional_patch_radius() float

Get the radius of the contact patch used to apply torsional friction

Search for “Torsional Patch Radius” in PhysX docs for more details

Returns

radius of the contact patch used to apply torsional friction. Allowed range [0, max_float].

Return type

float

Example:

>>> prim.get_torsional_patch_radius()
0.0
get_visibility() bool
Returns

true if the prim is visible in stage. false otherwise.

Return type

bool

Example:

>>> # get the visible state of an visible prim on the stage
>>> prim.get_visibility()
True
get_world_pose() Tuple[numpy.ndarray, numpy.ndarray]

Get prim’s pose with respect to the world’s frame

Returns

first index is the position in the world frame (with shape (3, )). Second index is quaternion orientation (with shape (4, )) in the world frame

Return type

Tuple[np.ndarray, np.ndarray]

Example:

>>> # if the prim is in position (1.0, 0.5, 0.0) with respect to the world frame
>>> position, orientation = prim.get_world_pose()
>>> position
[1.  0.5 0. ]
>>> orientation
[1. 0. 0. 0.]
get_world_scale() numpy.ndarray

Get prim’s scale with respect to the world’s frame

Returns

scale applied to the prim’s dimensions in the world frame. shape is (3, ).

Return type

np.ndarray

Example:

>>> prim.get_world_scale()
[1. 1. 1.]
initialize(physics_sim_view=None) None

Create a physics simulation view if not passed and using PhysX tensor API

Note

If the prim has been added to the world scene (e.g., world.scene.add(prim)), it will be automatically initialized when the world is reset (e.g., world.reset()).

Parameters

physics_sim_view (omni.physics.tensors.SimulationView, optional) – current physics simulation view. Defaults to None.

Example:

>>> prim.initialize()
is_valid() bool

Check if the prim path has a valid USD Prim at it

Returns

True is the current prim path corresponds to a valid prim in stage. False otherwise.

Return type

bool

Example:

>>> # given an existing and valid prim
>>> prims.is_valid()
True
is_visual_material_applied() bool

Check if there is a visual material applied

Returns

True if there is a visual material applied. False otherwise.

Return type

bool

Example:

>>> # given a visual material applied
>>> prim.is_visual_material_applied()
True
property name: Optional[str]

Returns: str: name given to the prim when instantiating it. Otherwise None.

Used to query if the prim is a non root articulation link

Returns

True if the prim itself is a non root link

Return type

bool

Example:

>>> # for a wrapped articulation (where the root prim has the Physics Articulation Root property applied)
>>> prim.non_root_articulation_link
False
post_reset() None

Reset the prim to its default state (position and orientation).

Note

For an articulation, in addition to configuring the root prim’s default position and spatial orientation (defined via the set_default_state method), the joint’s positions, velocities, and efforts (defined via the set_joints_default_state method) are imposed

Example:

>>> prim.post_reset()
property prim: pxr.Usd.Prim

Returns: Usd.Prim: USD Prim object that this object holds.

property prim_path: str

Returns: str: prim path in the stage

set_collision_approximation(approximation_type: str) None

Set the collision approximation

Approximation

Full name

Description

"none"

Triangle Mesh

The mesh geometry is used directly as a collider without any approximation

"convexDecomposition"

Convex Decomposition

A convex mesh decomposition is performed. This results in a set of convex mesh colliders

"convexHull"

Convex Hull

A convex hull of the mesh is generated and used as the collider

"boundingSphere"

Bounding Sphere

A bounding sphere is computed around the mesh and used as a collider

"boundingCube"

Bounding Cube

An optimally fitting box collider is computed around the mesh

"meshSimplification"

Mesh Simplification

A mesh simplification step is performed, resulting in a simplified triangle mesh collider

"sdf"

SDF Mesh

SDF (Signed-Distance-Field) use high-detail triangle meshes as collision shape

"sphereFill"

Sphere Approximation

A sphere mesh decomposition is performed. This results in a set of sphere colliders

Note

Use Convex Decomposition or SDF (Signed-Distance-Field) tri-meshes to capture details better

Warning

Switching to Convex Decomposition or SDF (Signed-Distance-Field) will have a simulation performance impact due to higher computational cost

Parameters

approximation_type (str) – approximation used for collision

Example:

>>> prim.set_collision_approximation("convexDecomposition")
set_collision_enabled(enabled: bool) None

Enable/disable the Collision API

Parameters

enabled (bool) – Whether to enable or disable the Collision API

Example:

>>> # disable collisions
>>> prim.set_collision_enabled(False)
set_contact_offset(offset: float) None

Set the contact offset

Shapes whose distance is less than the sum of their contact offset values will generate contacts

Search for Advanced Collision Detection in PhysX docs for more details

Warning

The contact offset must be positive and greater than the rest offset

Parameters

offset (float) – Contact offset of a collision shape. Allowed range [maximum(0, rest_offset), 0]. Default value is -inf, means default is picked by simulation based on the shape extent.

Example:

>>> prim.set_contact_offset(0.02)
set_default_state(position: Optional[Sequence[float]] = None, orientation: Optional[Sequence[float]] = None) None

Set the default state of the prim (position and orientation), that will be used after each reset.

Parameters
  • position (Optional[Sequence[float]], optional) – position in the world frame of the prim. shape is (3, ). Defaults to None, which means left unchanged.

  • orientation (Optional[Sequence[float]], optional) – quaternion orientation in the world frame of the prim. quaternion is scalar-first (w, x, y, z). shape is (4, ). Defaults to None, which means left unchanged.

Example:

>>> # configure default state
>>> prim.set_default_state(position=np.array([1.0, 0.5, 0.0]), orientation=np.array([1, 0, 0, 0]))
>>>
>>> # set default states during post-reset
>>> prim.post_reset()
set_local_pose(translation: Optional[Sequence[float]] = None, orientation: Optional[Sequence[float]] = None) None

Set prim’s pose with respect to the local frame (the prim’s parent frame).

Warning

This method will change (teleport) the prim pose immediately to the indicated value

Parameters
  • translation (Optional[Sequence[float]], optional) – translation in the local frame of the prim (with respect to its parent prim). shape is (3, ). Defaults to None, which means left unchanged.

  • orientation (Optional[Sequence[float]], optional) – quaternion orientation in the local frame of the prim. quaternion is scalar-first (w, x, y, z). shape is (4, ). Defaults to None, which means left unchanged.

Hint

This method belongs to the methods used to set the prim state

Example:

>>> prim.set_local_pose(translation=np.array([1.0, 0.5, 0.0]), orientation=np.array([1., 0., 0., 0.]))
set_local_scale(scale: Optional[Sequence[float]]) None

Set prim’s scale with respect to the local frame (the prim’s parent frame).

Parameters

scale (Optional[Sequence[float]]) – scale to be applied to the prim’s dimensions. shape is (3, ). Defaults to None, which means left unchanged.

Example:

>>> # scale prim 10 times smaller
>>> prim.set_local_scale(np.array([0.1, 0.1, 0.1]))
set_min_torsional_patch_radius(radius: float) None

Set the minimum radius of the contact patch used to apply torsional friction

Search for “Torsional Patch Radius” in PhysX docs for more details

Parameters

radius (float) – minimum radius of the contact patch used to apply torsional friction. Allowed range [0, max_float].

Example:

>>> prim.set_min_torsional_patch_radius(0.05)
set_radius(radius: float) None

Set the sphere radius

Parameters

radius (float) – sphere radius

Example:

>>> prim.set_radius(2.0)
set_rest_offset(offset: float) None

Set the rest offset

Two shapes will come to rest at a distance equal to the sum of their rest offset values. If the rest offset is 0, they should converge to touching exactly

Search for Advanced Collision Detection in PhysX docs for more details

Warning

The contact offset must be positive and greater than the rest offset

Parameters

offset (float) – Rest offset of a collision shape. Allowed range [-max_float, contact_offset. Default value is -inf, means default is picked by simulation. For rigid bodies its zero.

Example:

>>> prim.set_rest_offset(0.01)
set_torsional_patch_radius(radius: float) None

Set the radius of the contact patch used to apply torsional friction

Search for “Torsional Patch Radius” in PhysX docs for more details

Parameters

radius (float) – radius of the contact patch used to apply torsional friction. Allowed range [0, max_float].

Example:

>>> prim.set_torsional_patch_radius(0.1)
set_visibility(visible: bool) None

Set the visibility of the prim in stage

Parameters

visible (bool) – flag to set the visibility of the usd prim in stage.

Example:

>>> # make prim not visible in the stage
>>> prim.set_visibility(visible=False)
set_world_pose(position: Optional[Sequence[float]] = None, orientation: Optional[Sequence[float]] = None) None

Ses prim’s pose with respect to the world’s frame

Warning

This method will change (teleport) the prim pose immediately to the indicated value

Parameters
  • position (Optional[Sequence[float]], optional) – position in the world frame of the prim. shape is (3, ). Defaults to None, which means left unchanged.

  • orientation (Optional[Sequence[float]], optional) – quaternion orientation in the world frame of the prim. quaternion is scalar-first (w, x, y, z). shape is (4, ). Defaults to None, which means left unchanged.

Hint

This method belongs to the methods used to set the prim state

Example:

>>> prim.set_world_pose(position=np.array([1.0, 0.5, 0.0]), orientation=np.array([1., 0., 0., 0.]))

Dynamic Capsule

class DynamicCapsule(prim_path: str, name: str = 'dynamic_capsule', position: Optional[numpy.ndarray] = None, translation: Optional[numpy.ndarray] = None, orientation: Optional[numpy.ndarray] = None, scale: Optional[numpy.ndarray] = None, visible: Optional[bool] = None, color: Optional[numpy.ndarray] = None, radius: Optional[numpy.ndarray] = None, height: Optional[numpy.ndarray] = None, visual_material: Optional[omni.isaac.core.materials.visual_material.VisualMaterial] = None, physics_material: Optional[omni.isaac.core.materials.physics_material.PhysicsMaterial] = None, mass: Optional[float] = None, density: Optional[float] = None, linear_velocity: Optional[Sequence[float]] = None, angular_velocity: Optional[Sequence[float]] = None)

High level wrapper to create/encapsulate a dynamic capsule

Note

Dynamic capsules (Capsule shape) have collisions (Collider API) and rigid body dynamics (Rigid Body API)

Parameters
  • prim_path (str) – prim path of the Prim to encapsulate or create

  • name (str, optional) – shortname to be used as a key by Scene class. Note: needs to be unique if the object is added to the Scene. Defaults to “dynamic_capsule”.

  • position (Optional[Sequence[float]], optional) – position in the world frame of the prim. shape is (3, ). Defaults to None, which means left unchanged.

  • translation (Optional[Sequence[float]], optional) – translation in the local frame of the prim (with respect to its parent prim). shape is (3, ). Defaults to None, which means left unchanged.

  • orientation (Optional[Sequence[float]], optional) – quaternion orientation in the world/ local frame of the prim (depends if translation or position is specified). quaternion is scalar-first (w, x, y, z). shape is (4, ). Defaults to None, which means left unchanged.

  • scale (Optional[Sequence[float]], optional) – local scale to be applied to the prim’s dimensions. shape is (3, ). Defaults to None, which means left unchanged.

  • visible (bool, optional) – set to false for an invisible prim in the stage while rendering. Defaults to True.

  • color (Optional[np.ndarray], optional) – color of the visual shape. Defaults to None, which means 50% gray

  • radius (Optional[float], optional) – capsule radius. Defaults to None.

  • height (Optional[float], optional) – capsule height. Defaults to None.

  • visual_material (Optional[VisualMaterial], optional) – visual material to be applied to the held prim. Defaults to None. If not specified, a default visual material will be added.

  • physics_material (Optional[PhysicsMaterial], optional) – physics material to be applied to the held prim. Defaults to None. If not specified, a default physics material will be added.

  • mass (Optional[float], optional) – mass in kg. Defaults to None.

  • density (Optional[float], optional) – density. Defaults to None.

  • linear_velocity (Optional[np.ndarray], optional) – linear velocity in the world frame. Defaults to None.

  • angular_velocity (Optional[np.ndarray], optional) – angular velocity in the world frame. Defaults to None.

Example:

>>> from omni.isaac.core.objects import DynamicCapsule
>>> import numpy as np
>>>
>>> # create a red fixed capsule of mass 1kg at the given path
>>> prim = DynamicCapsule(
...     prim_path="/World/Xform/Capsule",
...     radius=0.5,
...     height=1.0,
...     color=np.array([1.0, 0.0, 0.0]),
...     mass=1.0
... )
>>> prim
<omni.isaac.core.objects.capsule.DynamicCapsule object at 0x7f4ff915f8e0>
apply_physics_material(physics_material: omni.isaac.core.materials.physics_material.PhysicsMaterial, weaker_than_descendants: bool = False)

Used to apply physics material to the held prim and optionally its descendants.

Parameters
  • physics_material (PhysicsMaterial) – physics material to be applied to the held prim. This where you want to define friction, restitution..etc. Note: if a physics material is not defined, the defaults will be used from PhysX.

  • weaker_than_descendants (bool, optional) – True if the material shouldn’t override the descendants materials, otherwise False. Defaults to False.

Example:

>>> from omni.isaac.core.materials import PhysicsMaterial
>>>
>>> # create a rigid body physical material
>>> material = PhysicsMaterial(
...     prim_path="/World/physics_material/aluminum",  # path to the material prim to create
...     dynamic_friction=0.4,
...     static_friction=1.1,
...     restitution=0.1
... )
>>> prim.apply_physics_material(material)
apply_visual_material(visual_material: omni.isaac.core.materials.visual_material.VisualMaterial, weaker_than_descendants: bool = False) None

Apply visual material to the held prim and optionally its descendants.

Parameters
  • visual_material (VisualMaterial) – visual material to be applied to the held prim. Currently supports PreviewSurface, OmniPBR and OmniGlass.

  • weaker_than_descendants (bool, optional) – True if the material shouldn’t override the descendants materials, otherwise False. Defaults to False.

Example:

>>> from omni.isaac.core.materials import OmniGlass
>>>
>>> # create a dark-red glass visual material
>>> material = OmniGlass(
...     prim_path="/World/material/glass",  # path to the material prim to create
...     ior=1.25,
...     depth=0.001,
...     thin_walled=False,
...     color=np.array([0.5, 0.0, 0.0])
... )
>>> prim.apply_visual_material(material)
disable_rigid_body_physics() None

Disable the rigid body physics

When disabled, the object will not be moved by external forces such as gravity and collisions

Example:

>>> prim.disable_rigid_body_physics()
enable_rigid_body_physics() None

Enable the rigid body physics

When enabled, the object will be moved by external forces such as gravity and collisions

Example:

>>> prim.enable_rigid_body_physics()
property geom: pxr.UsdGeom.Gprim

Returns: UsdGeom.Gprim: USD geometry object encapsulated.

get_angular_velocity()

Get the angular velocity of the rigid body

Returns

current angular velocity of the the rigid prim. Shape (3,).

Return type

np.ndarray

Example:

>>> prim.get_angular_velocity()]
[-0.01727393  0.00827609 -0.00040014]
get_applied_physics_material() omni.isaac.core.materials.physics_material.PhysicsMaterial

Return the current applied physics material in case it was applied using apply_physics_material or not.

Returns

the current applied physics material.

Return type

PhysicsMaterial

Example:

>>> # given a physics material applied
>>> prim.get_applied_physics_material()
<omni.isaac.core.materials.physics_material.PhysicsMaterial object at 0x7fb66c30cd30>
get_applied_visual_material() omni.isaac.core.materials.visual_material.VisualMaterial

Return the current applied visual material in case it was applied using apply_visual_material or it’s one of the following materials that was already applied before: PreviewSurface, OmniPBR and OmniGlass.

Returns

the current applied visual material if its type is currently supported.

Return type

VisualMaterial

Example:

>>> # given a visual material applied
>>> prim.get_applied_visual_material()
<omni.isaac.core.materials.omni_glass.OmniGlass object at 0x7f36263106a0>
get_collision_approximation() str

Get the collision approximation

Approximation

Full name

Description

"none"

Triangle Mesh

The mesh geometry is used directly as a collider without any approximation

"convexDecomposition"

Convex Decomposition

A convex mesh decomposition is performed. This results in a set of convex mesh colliders

"convexHull"

Convex Hull

A convex hull of the mesh is generated and used as the collider

"boundingSphere"

Bounding Sphere

A bounding sphere is computed around the mesh and used as a collider

"boundingCube"

Bounding Cube

An optimally fitting box collider is computed around the mesh

"meshSimplification"

Mesh Simplification

A mesh simplification step is performed, resulting in a simplified triangle mesh collider

"sdf"

SDF Mesh

SDF (Signed-Distance-Field) use high-detail triangle meshes as collision shape

"sphereFill"

Sphere Approximation

A sphere mesh decomposition is performed. This results in a set of sphere colliders

Returns

approximation used for collision

Return type

str

Example:

>>> prim.get_collision_approximation()
none
get_collision_enabled() bool

Check if the Collision API is enabled

Returns

True if the Collision API is enabled. Otherwise False

Return type

bool

Example:

>>> prim.get_collision_enabled()
True
get_contact_force_matrix(dt: float = 1.0) Union[numpy.ndarray, torch.Tensor]

If the object is initialized with filter_paths_expr list, this method returns the contact forces between the prims in the view and the filter prims. i.e., a matrix of dimension (self._contact_view.num_filters, 3) where num_filters is the determined according to the filter_paths_expr parameter.

Parameters

dt (float) – time step multiplier to convert the underlying impulses to forces. If the default value is used then the forces are in fact contact impulses

Returns

Net contact forces of the prims with shape (self._geometry_prim_view._contact_view.num_filters, 3).

Return type

Union[np.ndarray, torch.Tensor]

get_contact_offset() float

Get the contact offset

Shapes whose distance is less than the sum of their contact offset values will generate contacts

Search for Advanced Collision Detection in PhysX docs for more details

Returns

contact offset of the collision shape. Default value is -inf, means default is picked by simulation.

Return type

float

Example:

>>> prim.get_contact_offset()
-inf
get_current_dynamic_state() omni.isaac.core.utils.types.DynamicState

Get the current rigid body state (position, orientation and linear and angular velocities)

Returns

the dynamic state of the rigid body prim

Return type

DynamicState

Example:

>>> # for the example the rigid body is in free fall
>>> state = prim.get_current_dynamic_state()
>>> state
<omni.isaac.core.utils.types.DynamicState object at 0x7f740b36f670>
>>> state.position
[  0.99999857   2.0000017  -74.2862    ]
>>> state.orientation
[ 1.0000000e+00 -2.3961178e-07 -4.9891562e-09  4.9388258e-09]
>>> state.linear_velocity
[  0.        0.      -38.09554]
>>> state.angular_velocity
[0. 0. 0.]
get_default_state() omni.isaac.core.utils.types.DynamicState

Get the default rigid body state (position, orientation and linear and angular velocities)

Returns

returns the default state of the prim that is used after each reset

Return type

DynamicState

Example:

>>> state = prim.get_default_state()
>>> state
<omni.isaac.core.utils.types.DynamicState object at 0x7f7411fcbe20>
>>> state.position
[-7.8622378e-07  1.4450421e-06  1.6135601e-07]
>>> state.orientation
[ 9.9999994e-01 -2.7194994e-07  2.9607077e-07  2.7016510e-08]
>>> state.linear_velocity
[0. 0. 0.]
>>> state.angular_velocity
[0. 0. 0.]
get_density() float

Get the density of the rigid body

Returns

density of the rigid body.

Return type

float

Example:

>>> prim.get_density()
0
get_height() float

Get the capsule height

Returns

capsule height

Return type

float

Example:

>>> prim.get_height()
1.0
get_linear_velocity() numpy.ndarray

Get the linear velocity of the rigid body

Returns

current linear velocity of the the rigid prim. Shape (3,).

Return type

np.ndarray

Example:

>>> prim.get_linear_velocity()
[ 1.0812164e-04  6.1415871e-05 -2.1341663e-04]
get_local_pose() Tuple[numpy.ndarray, numpy.ndarray]

Get prim’s pose with respect to the local frame (the prim’s parent frame)

Returns

first index is the position in the local frame (with shape (3, )). Second index is quaternion orientation (with shape (4, )) in the local frame

Return type

Tuple[np.ndarray, np.ndarray]

Example:

>>> # if the prim is in position (1.0, 0.5, 0.0) with respect to the world frame
>>> position, orientation = prim.get_local_pose()
>>> position
[0. 0. 0.]
>>> orientation
[0. 0. 0.]
get_local_scale() numpy.ndarray

Get prim’s scale with respect to the local frame (the parent’s frame)

Returns

scale applied to the prim’s dimensions in the local frame. shape is (3, ).

Return type

np.ndarray

Example:

>>> prim.get_local_scale()
[1. 1. 1.]
get_mass() float

Get the mass of the rigid body

Returns

mass of the rigid body in kg.

Return type

float

Example:

>>> prim.get_mass()
0
get_min_torsional_patch_radius() float

Get the minimum radius of the contact patch used to apply torsional friction

Search for “Torsional Patch Radius” in PhysX docs for more details

Returns

minimum radius of the contact patch used to apply torsional friction. Allowed range [0, max_float].

Return type

float

Example:

>>> prim.get_min_torsional_patch_radius()
0.0
get_net_contact_forces(dt: float = 1.0) Union[numpy.ndarray, torch.Tensor]

If contact forces of the prims in the view are tracked, this method returns the net contact forces on prims. i.e., a matrix of dimension (1, 3)

Parameters

dt (float) – time step multiplier to convert the underlying impulses to forces. If the default value is used then the forces are in fact contact impulses

Returns

Net contact forces of the prims with shape (3).

Return type

Union[np.ndarray, torch.Tensor]

get_radius() float

Get the capsule radius

Returns

capsule radius

Return type

float

Example:

>>> prim.get_radius()
0.5
get_rest_offset() float

Get the rest offset

Two shapes will come to rest at a distance equal to the sum of their rest offset values. If the rest offset is 0, they should converge to touching exactly

Search for Advanced Collision Detection in PhysX docs for more details

Returns

rest offset of the collision shape.

Return type

float

Example:

>>> prim.get_rest_offset()
-inf
get_sleep_threshold() float

Get the threshold for the rigid body to enter a sleep state

Search for Rigid Body Dynamics > Sleeping in PhysX docs for more details

Returns

Mass-normalized kinetic energy threshold below which

an actor may go to sleep. Range: [0, inf) Defaults: 0.00005 * tolerancesSpeed* tolerancesSpeed Units: distance^2 / second^2.

Return type

float

Example:

>>> prim.get_sleep_threshold()
5e-05
get_torsional_patch_radius() float

Get the radius of the contact patch used to apply torsional friction

Search for “Torsional Patch Radius” in PhysX docs for more details

Returns

radius of the contact patch used to apply torsional friction. Allowed range [0, max_float].

Return type

float

Example:

>>> prim.get_torsional_patch_radius()
0.0
get_visibility() bool
Returns

true if the prim is visible in stage. false otherwise.

Return type

bool

Example:

>>> # get the visible state of an visible prim on the stage
>>> prim.get_visibility()
True
get_world_pose() Tuple[numpy.ndarray, numpy.ndarray]

Get prim’s pose with respect to the world’s frame

Returns

first index is the position in the world frame (with shape (3, )). Second index is quaternion orientation (with shape (4, )) in the world frame

Return type

Tuple[np.ndarray, np.ndarray]

Example:

>>> # if the prim is in position (1.0, 0.5, 0.0) with respect to the world frame
>>> position, orientation = prim.get_world_pose()
>>> position
[1.  0.5 0. ]
>>> orientation
[1. 0. 0. 0.]
get_world_scale() numpy.ndarray

Get prim’s scale with respect to the world’s frame

Returns

scale applied to the prim’s dimensions in the world frame. shape is (3, ).

Return type

np.ndarray

Example:

>>> prim.get_world_scale()
[1. 1. 1.]
initialize(physics_sim_view=None) None

Create a physics simulation view if not passed and using PhysX tensor API

Note

If the prim has been added to the world scene (e.g., world.scene.add(prim)), it will be automatically initialized when the world is reset (e.g., world.reset()).

Parameters

physics_sim_view (omni.physics.tensors.SimulationView, optional) – current physics simulation view. Defaults to None.

Example:

>>> prim.initialize()
is_valid() bool

Check if the prim path has a valid USD Prim at it

Returns

True is the current prim path corresponds to a valid prim in stage. False otherwise.

Return type

bool

Example:

>>> # given an existing and valid prim
>>> prims.is_valid()
True
is_visual_material_applied() bool

Check if there is a visual material applied

Returns

True if there is a visual material applied. False otherwise.

Return type

bool

Example:

>>> # given a visual material applied
>>> prim.is_visual_material_applied()
True
property name: Optional[str]

Returns: str: name given to the prim when instantiating it. Otherwise None.

Used to query if the prim is a non root articulation link

Returns

True if the prim itself is a non root link

Return type

bool

Example:

>>> # for a wrapped articulation (where the root prim has the Physics Articulation Root property applied)
>>> prim.non_root_articulation_link
False
post_reset() None

Reset the prim to its default state (position and orientation).

Note

For an articulation, in addition to configuring the root prim’s default position and spatial orientation (defined via the set_default_state method), the joint’s positions, velocities, and efforts (defined via the set_joints_default_state method) are imposed

Example:

>>> prim.post_reset()
property prim: pxr.Usd.Prim

Returns: Usd.Prim: USD Prim object that this object holds.

property prim_path: str

Returns: str: prim path in the stage

set_angular_velocity(velocity: numpy.ndarray) None

Set the angular velocity of the rigid body in stage

Warning

This method will immediately set the articulation state

Parameters

velocity (np.ndarray) – angular velocity to set the rigid prim to. Shape (3,).

Hint

This method belongs to the methods used to set the rigid prim kinematic state:

set_linear_velocity, set_angular_velocity

Example:

>>> prim.set_angular_velocity(np.array([0.0, 0.0, 10.0]))
set_collision_approximation(approximation_type: str) None

Set the collision approximation

Approximation

Full name

Description

"none"

Triangle Mesh

The mesh geometry is used directly as a collider without any approximation

"convexDecomposition"

Convex Decomposition

A convex mesh decomposition is performed. This results in a set of convex mesh colliders

"convexHull"

Convex Hull

A convex hull of the mesh is generated and used as the collider

"boundingSphere"

Bounding Sphere

A bounding sphere is computed around the mesh and used as a collider

"boundingCube"

Bounding Cube

An optimally fitting box collider is computed around the mesh

"meshSimplification"

Mesh Simplification

A mesh simplification step is performed, resulting in a simplified triangle mesh collider

"sdf"

SDF Mesh

SDF (Signed-Distance-Field) use high-detail triangle meshes as collision shape

"sphereFill"

Sphere Approximation

A sphere mesh decomposition is performed. This results in a set of sphere colliders

Note

Use Convex Decomposition or SDF (Signed-Distance-Field) tri-meshes to capture details better

Warning

Switching to Convex Decomposition or SDF (Signed-Distance-Field) will have a simulation performance impact due to higher computational cost

Parameters

approximation_type (str) – approximation used for collision

Example:

>>> prim.set_collision_approximation("convexDecomposition")
set_collision_enabled(enabled: bool) None

Enable/disable the Collision API

Parameters

enabled (bool) – Whether to enable or disable the Collision API

Example:

>>> # disable collisions
>>> prim.set_collision_enabled(False)
set_contact_offset(offset: float) None

Set the contact offset

Shapes whose distance is less than the sum of their contact offset values will generate contacts

Search for Advanced Collision Detection in PhysX docs for more details

Warning

The contact offset must be positive and greater than the rest offset

Parameters

offset (float) – Contact offset of a collision shape. Allowed range [maximum(0, rest_offset), 0]. Default value is -inf, means default is picked by simulation based on the shape extent.

Example:

>>> prim.set_contact_offset(0.02)
set_default_state(position: Optional[Sequence[float]] = None, orientation: Optional[Sequence[float]] = None, linear_velocity: Optional[numpy.ndarray] = None, angular_velocity: Optional[numpy.ndarray] = None) None

Set the default state of the prim (position, orientation and linear and angular velocities), that will be used after each reset

Note

The default states will be set during post-reset (e.g., calling .post_reset() or world.reset() methods)

Parameters
  • position (Optional[Sequence[float]], optional) – position in the world frame of the prim. shape is (3, ). Defaults to None, which means left unchanged.

  • orientation (Optional[Sequence[float]], optional) – quaternion orientation in the world frame of the prim. quaternion is scalar-first (w, x, y, z). shape is (4, ). Defaults to None, which means left unchanged.

  • linear_velocity (np.ndarray) – linear velocity to set the rigid prim to. Shape (3,).

  • angular_velocity (np.ndarray) – angular velocity to set the rigid prim to. Shape (3,).

Example:

>>> prim.set_default_state(
...     position=np.array([1.0, 2.0, 3.0]),
...     orientation=np.array([1.0, 0.0, 0.0, 0.0]),
...     linear_velocity=np.array([0.0, 0.0, 0.0]),
...     angular_velocity=np.array([0.0, 0.0, 0.0])
... )
>>>
>>> prim.post_reset()
set_density(density: float) None

Set the density of the rigid body

Parameters

mass (float) – density of the rigid body.

Example:

>>> prim.set_density(0.9)
set_height(height: float) None

Set the capsule height

Parameters

height (float) – capsule height

Example:

>>> prim.set_height(2.0)
set_linear_velocity(velocity: numpy.ndarray)

Set the linear velocity of the rigid body in stage

Warning

This method will immediately set the rigid prim state

Parameters

velocity (np.ndarray) – linear velocity to set the rigid prim to. Shape (3,).

Hint

This method belongs to the methods used to set the rigid prim kinematic state:

set_linear_velocity, set_angular_velocity

Example:

>>> prim.set_linear_velocity(np.array([5.0, 0.0, 0.0]))
set_local_pose(translation: Optional[Sequence[float]] = None, orientation: Optional[Sequence[float]] = None) None

Set prim’s pose with respect to the local frame (the prim’s parent frame).

Warning

This method will change (teleport) the prim pose immediately to the indicated value

Parameters
  • translation (Optional[Sequence[float]], optional) – translation in the local frame of the prim (with respect to its parent prim). shape is (3, ). Defaults to None, which means left unchanged.

  • orientation (Optional[Sequence[float]], optional) – quaternion orientation in the local frame of the prim. quaternion is scalar-first (w, x, y, z). shape is (4, ). Defaults to None, which means left unchanged.

Hint

This method belongs to the methods used to set the prim state

Example:

>>> prim.set_local_pose(translation=np.array([1.0, 0.5, 0.0]), orientation=np.array([1., 0., 0., 0.]))
set_local_scale(scale: Optional[Sequence[float]]) None

Set prim’s scale with respect to the local frame (the prim’s parent frame).

Parameters

scale (Optional[Sequence[float]]) – scale to be applied to the prim’s dimensions. shape is (3, ). Defaults to None, which means left unchanged.

Example:

>>> # scale prim 10 times smaller
>>> prim.set_local_scale(np.array([0.1, 0.1, 0.1]))
set_mass(mass: float) None

Set the mass of the rigid body

Parameters

mass (float) – mass of the rigid body in kg.

Example:

>>> prim.set_mass(1.0)
set_min_torsional_patch_radius(radius: float) None

Set the minimum radius of the contact patch used to apply torsional friction

Search for “Torsional Patch Radius” in PhysX docs for more details

Parameters

radius (float) – minimum radius of the contact patch used to apply torsional friction. Allowed range [0, max_float].

Example:

>>> prim.set_min_torsional_patch_radius(0.05)
set_radius(radius: float) None

Set the capsule radius

Parameters

radius (float) – capsule radius

Example:

>>> prim.set_radius(1.0)
set_rest_offset(offset: float) None

Set the rest offset

Two shapes will come to rest at a distance equal to the sum of their rest offset values. If the rest offset is 0, they should converge to touching exactly

Search for Advanced Collision Detection in PhysX docs for more details

Warning

The contact offset must be positive and greater than the rest offset

Parameters

offset (float) – Rest offset of a collision shape. Allowed range [-max_float, contact_offset. Default value is -inf, means default is picked by simulation. For rigid bodies its zero.

Example:

>>> prim.set_rest_offset(0.01)
set_sleep_threshold(threshold: float) None

Set the threshold for the rigid body to enter a sleep state

Search for Rigid Body Dynamics > Sleeping in PhysX docs for more details

Parameters

threshold (float) – Mass-normalized kinetic energy threshold below which an actor may go to sleep. Range: [0, inf) Defaults: 0.00005 * tolerancesSpeed* tolerancesSpeed Units: distance^2 / second^2.

Example:

>>> prim.set_sleep_threshold(1e-5)
set_torsional_patch_radius(radius: float) None

Set the radius of the contact patch used to apply torsional friction

Search for “Torsional Patch Radius” in PhysX docs for more details

Parameters

radius (float) – radius of the contact patch used to apply torsional friction. Allowed range [0, max_float].

Example:

>>> prim.set_torsional_patch_radius(0.1)
set_visibility(visible: bool) None

Set the visibility of the prim in stage

Parameters

visible (bool) – flag to set the visibility of the usd prim in stage.

Example:

>>> # make prim not visible in the stage
>>> prim.set_visibility(visible=False)
set_world_pose(position: Optional[Sequence[float]] = None, orientation: Optional[Sequence[float]] = None) None

Ses prim’s pose with respect to the world’s frame

Warning

This method will change (teleport) the prim pose immediately to the indicated value

Parameters
  • position (Optional[Sequence[float]], optional) – position in the world frame of the prim. shape is (3, ). Defaults to None, which means left unchanged.

  • orientation (Optional[Sequence[float]], optional) – quaternion orientation in the world frame of the prim. quaternion is scalar-first (w, x, y, z). shape is (4, ). Defaults to None, which means left unchanged.

Hint

This method belongs to the methods used to set the prim state

Example:

>>> prim.set_world_pose(position=np.array([1.0, 0.5, 0.0]), orientation=np.array([1., 0., 0., 0.]))

Dynamic Cone

class DynamicCone(prim_path: str, name: str = 'dynamic_cone', position: Optional[numpy.ndarray] = None, translation: Optional[numpy.ndarray] = None, orientation: Optional[numpy.ndarray] = None, scale: Optional[numpy.ndarray] = None, visible: Optional[bool] = None, color: Optional[numpy.ndarray] = None, radius: Optional[numpy.ndarray] = None, height: Optional[numpy.ndarray] = None, visual_material: Optional[omni.isaac.core.materials.visual_material.VisualMaterial] = None, physics_material: Optional[omni.isaac.core.materials.physics_material.PhysicsMaterial] = None, mass: Optional[float] = None, density: Optional[float] = None, linear_velocity: Optional[Sequence[float]] = None, angular_velocity: Optional[Sequence[float]] = None)

High level wrapper to create/encapsulate a dynamic cone

Note

Dynamic cones (Cone shape) have collisions (Collider API) and rigid body dynamics (Rigid Body API)

Parameters
  • prim_path (str) – prim path of the Prim to encapsulate or create

  • name (str, optional) – shortname to be used as a key by Scene class. Note: needs to be unique if the object is added to the Scene. Defaults to “dynamic_cone”.

  • position (Optional[Sequence[float]], optional) – position in the world frame of the prim. shape is (3, ). Defaults to None, which means left unchanged.

  • translation (Optional[Sequence[float]], optional) – translation in the local frame of the prim (with respect to its parent prim). shape is (3, ). Defaults to None, which means left unchanged.

  • orientation (Optional[Sequence[float]], optional) – quaternion orientation in the world/ local frame of the prim (depends if translation or position is specified). quaternion is scalar-first (w, x, y, z). shape is (4, ). Defaults to None, which means left unchanged.

  • scale (Optional[Sequence[float]], optional) – local scale to be applied to the prim’s dimensions. shape is (3, ). Defaults to None, which means left unchanged.

  • visible (bool, optional) – set to false for an invisible prim in the stage while rendering. Defaults to True.

  • color (Optional[np.ndarray], optional) – color of the visual shape. Defaults to None, which means 50% gray

  • radius (Optional[float], optional) – base radius. Defaults to None.

  • height (Optional[float], optional) – cone height. Defaults to None.

  • visual_material (Optional[VisualMaterial], optional) – visual material to be applied to the held prim. Defaults to None. If not specified, a default visual material will be added.

  • physics_material (Optional[PhysicsMaterial], optional) – physics material to be applied to the held prim. Defaults to None. If not specified, a default physics material will be added.

  • mass (Optional[float], optional) – mass in kg. Defaults to None.

  • density (Optional[float], optional) – density. Defaults to None.

  • linear_velocity (Optional[np.ndarray], optional) – linear velocity in the world frame. Defaults to None.

  • angular_velocity (Optional[np.ndarray], optional) – angular velocity in the world frame. Defaults to None.

Example:

>>> from omni.isaac.core.objects import DynamicCone
>>> import numpy as np
>>>
>>> # create a red dynamic cone of mass 1kg at the given path
>>> prim = DynamicCone(
...     prim_path="/World/Xform/Cone",
...     radius=0.5,
...     height=1.0,
...     color=np.array([1.0, 0.0, 0.0]),
...     mass=1.0
... )
>>> prim
<omni.isaac.core.objects.cone.DynamicCone object at 0x7f4f9f5d11b0>
apply_physics_material(physics_material: omni.isaac.core.materials.physics_material.PhysicsMaterial, weaker_than_descendants: bool = False)

Used to apply physics material to the held prim and optionally its descendants.

Parameters
  • physics_material (PhysicsMaterial) – physics material to be applied to the held prim. This where you want to define friction, restitution..etc. Note: if a physics material is not defined, the defaults will be used from PhysX.

  • weaker_than_descendants (bool, optional) – True if the material shouldn’t override the descendants materials, otherwise False. Defaults to False.

Example:

>>> from omni.isaac.core.materials import PhysicsMaterial
>>>
>>> # create a rigid body physical material
>>> material = PhysicsMaterial(
...     prim_path="/World/physics_material/aluminum",  # path to the material prim to create
...     dynamic_friction=0.4,
...     static_friction=1.1,
...     restitution=0.1
... )
>>> prim.apply_physics_material(material)
apply_visual_material(visual_material: omni.isaac.core.materials.visual_material.VisualMaterial, weaker_than_descendants: bool = False) None

Apply visual material to the held prim and optionally its descendants.

Parameters
  • visual_material (VisualMaterial) – visual material to be applied to the held prim. Currently supports PreviewSurface, OmniPBR and OmniGlass.

  • weaker_than_descendants (bool, optional) – True if the material shouldn’t override the descendants materials, otherwise False. Defaults to False.

Example:

>>> from omni.isaac.core.materials import OmniGlass
>>>
>>> # create a dark-red glass visual material
>>> material = OmniGlass(
...     prim_path="/World/material/glass",  # path to the material prim to create
...     ior=1.25,
...     depth=0.001,
...     thin_walled=False,
...     color=np.array([0.5, 0.0, 0.0])
... )
>>> prim.apply_visual_material(material)
disable_rigid_body_physics() None

Disable the rigid body physics

When disabled, the object will not be moved by external forces such as gravity and collisions

Example:

>>> prim.disable_rigid_body_physics()
enable_rigid_body_physics() None

Enable the rigid body physics

When enabled, the object will be moved by external forces such as gravity and collisions

Example:

>>> prim.enable_rigid_body_physics()
property geom: pxr.UsdGeom.Gprim

Returns: UsdGeom.Gprim: USD geometry object encapsulated.

get_angular_velocity()

Get the angular velocity of the rigid body

Returns

current angular velocity of the the rigid prim. Shape (3,).

Return type

np.ndarray

Example:

>>> prim.get_angular_velocity()]
[-0.01727393  0.00827609 -0.00040014]
get_applied_physics_material() omni.isaac.core.materials.physics_material.PhysicsMaterial

Return the current applied physics material in case it was applied using apply_physics_material or not.

Returns

the current applied physics material.

Return type

PhysicsMaterial

Example:

>>> # given a physics material applied
>>> prim.get_applied_physics_material()
<omni.isaac.core.materials.physics_material.PhysicsMaterial object at 0x7fb66c30cd30>
get_applied_visual_material() omni.isaac.core.materials.visual_material.VisualMaterial

Return the current applied visual material in case it was applied using apply_visual_material or it’s one of the following materials that was already applied before: PreviewSurface, OmniPBR and OmniGlass.

Returns

the current applied visual material if its type is currently supported.

Return type

VisualMaterial

Example:

>>> # given a visual material applied
>>> prim.get_applied_visual_material()
<omni.isaac.core.materials.omni_glass.OmniGlass object at 0x7f36263106a0>
get_collision_approximation() str

Get the collision approximation

Approximation

Full name

Description

"none"

Triangle Mesh

The mesh geometry is used directly as a collider without any approximation

"convexDecomposition"

Convex Decomposition

A convex mesh decomposition is performed. This results in a set of convex mesh colliders

"convexHull"

Convex Hull

A convex hull of the mesh is generated and used as the collider

"boundingSphere"

Bounding Sphere

A bounding sphere is computed around the mesh and used as a collider

"boundingCube"

Bounding Cube

An optimally fitting box collider is computed around the mesh

"meshSimplification"

Mesh Simplification

A mesh simplification step is performed, resulting in a simplified triangle mesh collider

"sdf"

SDF Mesh

SDF (Signed-Distance-Field) use high-detail triangle meshes as collision shape

"sphereFill"

Sphere Approximation

A sphere mesh decomposition is performed. This results in a set of sphere colliders

Returns

approximation used for collision

Return type

str

Example:

>>> prim.get_collision_approximation()
none
get_collision_enabled() bool

Check if the Collision API is enabled

Returns

True if the Collision API is enabled. Otherwise False

Return type

bool

Example:

>>> prim.get_collision_enabled()
True
get_contact_force_matrix(dt: float = 1.0) Union[numpy.ndarray, torch.Tensor]

If the object is initialized with filter_paths_expr list, this method returns the contact forces between the prims in the view and the filter prims. i.e., a matrix of dimension (self._contact_view.num_filters, 3) where num_filters is the determined according to the filter_paths_expr parameter.

Parameters

dt (float) – time step multiplier to convert the underlying impulses to forces. If the default value is used then the forces are in fact contact impulses

Returns

Net contact forces of the prims with shape (self._geometry_prim_view._contact_view.num_filters, 3).

Return type

Union[np.ndarray, torch.Tensor]

get_contact_offset() float

Get the contact offset

Shapes whose distance is less than the sum of their contact offset values will generate contacts

Search for Advanced Collision Detection in PhysX docs for more details

Returns

contact offset of the collision shape. Default value is -inf, means default is picked by simulation.

Return type

float

Example:

>>> prim.get_contact_offset()
-inf
get_current_dynamic_state() omni.isaac.core.utils.types.DynamicState

Get the current rigid body state (position, orientation and linear and angular velocities)

Returns

the dynamic state of the rigid body prim

Return type

DynamicState

Example:

>>> # for the example the rigid body is in free fall
>>> state = prim.get_current_dynamic_state()
>>> state
<omni.isaac.core.utils.types.DynamicState object at 0x7f740b36f670>
>>> state.position
[  0.99999857   2.0000017  -74.2862    ]
>>> state.orientation
[ 1.0000000e+00 -2.3961178e-07 -4.9891562e-09  4.9388258e-09]
>>> state.linear_velocity
[  0.        0.      -38.09554]
>>> state.angular_velocity
[0. 0. 0.]
get_default_state() omni.isaac.core.utils.types.DynamicState

Get the default rigid body state (position, orientation and linear and angular velocities)

Returns

returns the default state of the prim that is used after each reset

Return type

DynamicState

Example:

>>> state = prim.get_default_state()
>>> state
<omni.isaac.core.utils.types.DynamicState object at 0x7f7411fcbe20>
>>> state.position
[-7.8622378e-07  1.4450421e-06  1.6135601e-07]
>>> state.orientation
[ 9.9999994e-01 -2.7194994e-07  2.9607077e-07  2.7016510e-08]
>>> state.linear_velocity
[0. 0. 0.]
>>> state.angular_velocity
[0. 0. 0.]
get_density() float

Get the density of the rigid body

Returns

density of the rigid body.

Return type

float

Example:

>>> prim.get_density()
0
get_height() float

Get the cone height

Returns

cone height

Return type

float

Example:

>>> prim.get_height()
1.0
get_linear_velocity() numpy.ndarray

Get the linear velocity of the rigid body

Returns

current linear velocity of the the rigid prim. Shape (3,).

Return type

np.ndarray

Example:

>>> prim.get_linear_velocity()
[ 1.0812164e-04  6.1415871e-05 -2.1341663e-04]
get_local_pose() Tuple[numpy.ndarray, numpy.ndarray]

Get prim’s pose with respect to the local frame (the prim’s parent frame)

Returns

first index is the position in the local frame (with shape (3, )). Second index is quaternion orientation (with shape (4, )) in the local frame

Return type

Tuple[np.ndarray, np.ndarray]

Example:

>>> # if the prim is in position (1.0, 0.5, 0.0) with respect to the world frame
>>> position, orientation = prim.get_local_pose()
>>> position
[0. 0. 0.]
>>> orientation
[0. 0. 0.]
get_local_scale() numpy.ndarray

Get prim’s scale with respect to the local frame (the parent’s frame)

Returns

scale applied to the prim’s dimensions in the local frame. shape is (3, ).

Return type

np.ndarray

Example:

>>> prim.get_local_scale()
[1. 1. 1.]
get_mass() float

Get the mass of the rigid body

Returns

mass of the rigid body in kg.

Return type

float

Example:

>>> prim.get_mass()
0
get_min_torsional_patch_radius() float

Get the minimum radius of the contact patch used to apply torsional friction

Search for “Torsional Patch Radius” in PhysX docs for more details

Returns

minimum radius of the contact patch used to apply torsional friction. Allowed range [0, max_float].

Return type

float

Example:

>>> prim.get_min_torsional_patch_radius()
0.0
get_net_contact_forces(dt: float = 1.0) Union[numpy.ndarray, torch.Tensor]

If contact forces of the prims in the view are tracked, this method returns the net contact forces on prims. i.e., a matrix of dimension (1, 3)

Parameters

dt (float) – time step multiplier to convert the underlying impulses to forces. If the default value is used then the forces are in fact contact impulses

Returns

Net contact forces of the prims with shape (3).

Return type

Union[np.ndarray, torch.Tensor]

get_radius() float

Get the base radius

Returns

base radius

Return type

float

Example:

>>> prim.get_radius()
0.5
get_rest_offset() float

Get the rest offset

Two shapes will come to rest at a distance equal to the sum of their rest offset values. If the rest offset is 0, they should converge to touching exactly

Search for Advanced Collision Detection in PhysX docs for more details

Returns

rest offset of the collision shape.

Return type

float

Example:

>>> prim.get_rest_offset()
-inf
get_sleep_threshold() float

Get the threshold for the rigid body to enter a sleep state

Search for Rigid Body Dynamics > Sleeping in PhysX docs for more details

Returns

Mass-normalized kinetic energy threshold below which

an actor may go to sleep. Range: [0, inf) Defaults: 0.00005 * tolerancesSpeed* tolerancesSpeed Units: distance^2 / second^2.

Return type

float

Example:

>>> prim.get_sleep_threshold()
5e-05
get_torsional_patch_radius() float

Get the radius of the contact patch used to apply torsional friction

Search for “Torsional Patch Radius” in PhysX docs for more details

Returns

radius of the contact patch used to apply torsional friction. Allowed range [0, max_float].

Return type

float

Example:

>>> prim.get_torsional_patch_radius()
0.0
get_visibility() bool
Returns

true if the prim is visible in stage. false otherwise.

Return type

bool

Example:

>>> # get the visible state of an visible prim on the stage
>>> prim.get_visibility()
True
get_world_pose() Tuple[numpy.ndarray, numpy.ndarray]

Get prim’s pose with respect to the world’s frame

Returns

first index is the position in the world frame (with shape (3, )). Second index is quaternion orientation (with shape (4, )) in the world frame

Return type

Tuple[np.ndarray, np.ndarray]

Example:

>>> # if the prim is in position (1.0, 0.5, 0.0) with respect to the world frame
>>> position, orientation = prim.get_world_pose()
>>> position
[1.  0.5 0. ]
>>> orientation
[1. 0. 0. 0.]
get_world_scale() numpy.ndarray

Get prim’s scale with respect to the world’s frame

Returns

scale applied to the prim’s dimensions in the world frame. shape is (3, ).

Return type

np.ndarray

Example:

>>> prim.get_world_scale()
[1. 1. 1.]
initialize(physics_sim_view=None) None

Create a physics simulation view if not passed and using PhysX tensor API

Note

If the prim has been added to the world scene (e.g., world.scene.add(prim)), it will be automatically initialized when the world is reset (e.g., world.reset()).

Parameters

physics_sim_view (omni.physics.tensors.SimulationView, optional) – current physics simulation view. Defaults to None.

Example:

>>> prim.initialize()
is_valid() bool

Check if the prim path has a valid USD Prim at it

Returns

True is the current prim path corresponds to a valid prim in stage. False otherwise.

Return type

bool

Example:

>>> # given an existing and valid prim
>>> prims.is_valid()
True
is_visual_material_applied() bool

Check if there is a visual material applied

Returns

True if there is a visual material applied. False otherwise.

Return type

bool

Example:

>>> # given a visual material applied
>>> prim.is_visual_material_applied()
True
property name: Optional[str]

Returns: str: name given to the prim when instantiating it. Otherwise None.

Used to query if the prim is a non root articulation link

Returns

True if the prim itself is a non root link

Return type

bool

Example:

>>> # for a wrapped articulation (where the root prim has the Physics Articulation Root property applied)
>>> prim.non_root_articulation_link
False
post_reset() None

Reset the prim to its default state (position and orientation).

Note

For an articulation, in addition to configuring the root prim’s default position and spatial orientation (defined via the set_default_state method), the joint’s positions, velocities, and efforts (defined via the set_joints_default_state method) are imposed

Example:

>>> prim.post_reset()
property prim: pxr.Usd.Prim

Returns: Usd.Prim: USD Prim object that this object holds.

property prim_path: str

Returns: str: prim path in the stage

set_angular_velocity(velocity: numpy.ndarray) None

Set the angular velocity of the rigid body in stage

Warning

This method will immediately set the articulation state

Parameters

velocity (np.ndarray) – angular velocity to set the rigid prim to. Shape (3,).

Hint

This method belongs to the methods used to set the rigid prim kinematic state:

set_linear_velocity, set_angular_velocity

Example:

>>> prim.set_angular_velocity(np.array([0.0, 0.0, 10.0]))
set_collision_approximation(approximation_type: str) None

Set the collision approximation

Approximation

Full name

Description

"none"

Triangle Mesh

The mesh geometry is used directly as a collider without any approximation

"convexDecomposition"

Convex Decomposition

A convex mesh decomposition is performed. This results in a set of convex mesh colliders

"convexHull"

Convex Hull

A convex hull of the mesh is generated and used as the collider

"boundingSphere"

Bounding Sphere

A bounding sphere is computed around the mesh and used as a collider

"boundingCube"

Bounding Cube

An optimally fitting box collider is computed around the mesh

"meshSimplification"

Mesh Simplification

A mesh simplification step is performed, resulting in a simplified triangle mesh collider

"sdf"

SDF Mesh

SDF (Signed-Distance-Field) use high-detail triangle meshes as collision shape

"sphereFill"

Sphere Approximation

A sphere mesh decomposition is performed. This results in a set of sphere colliders

Note

Use Convex Decomposition or SDF (Signed-Distance-Field) tri-meshes to capture details better

Warning

Switching to Convex Decomposition or SDF (Signed-Distance-Field) will have a simulation performance impact due to higher computational cost

Parameters

approximation_type (str) – approximation used for collision

Example:

>>> prim.set_collision_approximation("convexDecomposition")
set_collision_enabled(enabled: bool) None

Enable/disable the Collision API

Parameters

enabled (bool) – Whether to enable or disable the Collision API

Example:

>>> # disable collisions
>>> prim.set_collision_enabled(False)
set_contact_offset(offset: float) None

Set the contact offset

Shapes whose distance is less than the sum of their contact offset values will generate contacts

Search for Advanced Collision Detection in PhysX docs for more details

Warning

The contact offset must be positive and greater than the rest offset

Parameters

offset (float) – Contact offset of a collision shape. Allowed range [maximum(0, rest_offset), 0]. Default value is -inf, means default is picked by simulation based on the shape extent.

Example:

>>> prim.set_contact_offset(0.02)
set_default_state(position: Optional[Sequence[float]] = None, orientation: Optional[Sequence[float]] = None, linear_velocity: Optional[numpy.ndarray] = None, angular_velocity: Optional[numpy.ndarray] = None) None

Set the default state of the prim (position, orientation and linear and angular velocities), that will be used after each reset

Note

The default states will be set during post-reset (e.g., calling .post_reset() or world.reset() methods)

Parameters
  • position (Optional[Sequence[float]], optional) – position in the world frame of the prim. shape is (3, ). Defaults to None, which means left unchanged.

  • orientation (Optional[Sequence[float]], optional) – quaternion orientation in the world frame of the prim. quaternion is scalar-first (w, x, y, z). shape is (4, ). Defaults to None, which means left unchanged.

  • linear_velocity (np.ndarray) – linear velocity to set the rigid prim to. Shape (3,).

  • angular_velocity (np.ndarray) – angular velocity to set the rigid prim to. Shape (3,).

Example:

>>> prim.set_default_state(
...     position=np.array([1.0, 2.0, 3.0]),
...     orientation=np.array([1.0, 0.0, 0.0, 0.0]),
...     linear_velocity=np.array([0.0, 0.0, 0.0]),
...     angular_velocity=np.array([0.0, 0.0, 0.0])
... )
>>>
>>> prim.post_reset()
set_density(density: float) None

Set the density of the rigid body

Parameters

mass (float) – density of the rigid body.

Example:

>>> prim.set_density(0.9)
set_height(height: float) None

Set the cone height

Parameters

height (float) – cone height

Example:

>>> prim.set_height(2.0)
set_linear_velocity(velocity: numpy.ndarray)

Set the linear velocity of the rigid body in stage

Warning

This method will immediately set the rigid prim state

Parameters

velocity (np.ndarray) – linear velocity to set the rigid prim to. Shape (3,).

Hint

This method belongs to the methods used to set the rigid prim kinematic state:

set_linear_velocity, set_angular_velocity

Example:

>>> prim.set_linear_velocity(np.array([5.0, 0.0, 0.0]))
set_local_pose(translation: Optional[Sequence[float]] = None, orientation: Optional[Sequence[float]] = None) None

Set prim’s pose with respect to the local frame (the prim’s parent frame).

Warning

This method will change (teleport) the prim pose immediately to the indicated value

Parameters
  • translation (Optional[Sequence[float]], optional) – translation in the local frame of the prim (with respect to its parent prim). shape is (3, ). Defaults to None, which means left unchanged.

  • orientation (Optional[Sequence[float]], optional) – quaternion orientation in the local frame of the prim. quaternion is scalar-first (w, x, y, z). shape is (4, ). Defaults to None, which means left unchanged.

Hint

This method belongs to the methods used to set the prim state

Example:

>>> prim.set_local_pose(translation=np.array([1.0, 0.5, 0.0]), orientation=np.array([1., 0., 0., 0.]))
set_local_scale(scale: Optional[Sequence[float]]) None

Set prim’s scale with respect to the local frame (the prim’s parent frame).

Parameters

scale (Optional[Sequence[float]]) – scale to be applied to the prim’s dimensions. shape is (3, ). Defaults to None, which means left unchanged.

Example:

>>> # scale prim 10 times smaller
>>> prim.set_local_scale(np.array([0.1, 0.1, 0.1]))
set_mass(mass: float) None

Set the mass of the rigid body

Parameters

mass (float) – mass of the rigid body in kg.

Example:

>>> prim.set_mass(1.0)
set_min_torsional_patch_radius(radius: float) None

Set the minimum radius of the contact patch used to apply torsional friction

Search for “Torsional Patch Radius” in PhysX docs for more details

Parameters

radius (float) – minimum radius of the contact patch used to apply torsional friction. Allowed range [0, max_float].

Example:

>>> prim.set_min_torsional_patch_radius(0.05)
set_radius(radius: float) None

Set the base radius

Parameters

radius (float) – base radius

Example:

>>> prim.set_radius(1.0)
set_rest_offset(offset: float) None

Set the rest offset

Two shapes will come to rest at a distance equal to the sum of their rest offset values. If the rest offset is 0, they should converge to touching exactly

Search for Advanced Collision Detection in PhysX docs for more details

Warning

The contact offset must be positive and greater than the rest offset

Parameters

offset (float) – Rest offset of a collision shape. Allowed range [-max_float, contact_offset. Default value is -inf, means default is picked by simulation. For rigid bodies its zero.

Example:

>>> prim.set_rest_offset(0.01)
set_sleep_threshold(threshold: float) None

Set the threshold for the rigid body to enter a sleep state

Search for Rigid Body Dynamics > Sleeping in PhysX docs for more details

Parameters

threshold (float) – Mass-normalized kinetic energy threshold below which an actor may go to sleep. Range: [0, inf) Defaults: 0.00005 * tolerancesSpeed* tolerancesSpeed Units: distance^2 / second^2.

Example:

>>> prim.set_sleep_threshold(1e-5)
set_torsional_patch_radius(radius: float) None

Set the radius of the contact patch used to apply torsional friction

Search for “Torsional Patch Radius” in PhysX docs for more details

Parameters

radius (float) – radius of the contact patch used to apply torsional friction. Allowed range [0, max_float].

Example:

>>> prim.set_torsional_patch_radius(0.1)
set_visibility(visible: bool) None

Set the visibility of the prim in stage

Parameters

visible (bool) – flag to set the visibility of the usd prim in stage.

Example:

>>> # make prim not visible in the stage
>>> prim.set_visibility(visible=False)
set_world_pose(position: Optional[Sequence[float]] = None, orientation: Optional[Sequence[float]] = None) None

Ses prim’s pose with respect to the world’s frame

Warning

This method will change (teleport) the prim pose immediately to the indicated value

Parameters
  • position (Optional[Sequence[float]], optional) – position in the world frame of the prim. shape is (3, ). Defaults to None, which means left unchanged.

  • orientation (Optional[Sequence[float]], optional) – quaternion orientation in the world frame of the prim. quaternion is scalar-first (w, x, y, z). shape is (4, ). Defaults to None, which means left unchanged.

Hint

This method belongs to the methods used to set the prim state

Example:

>>> prim.set_world_pose(position=np.array([1.0, 0.5, 0.0]), orientation=np.array([1., 0., 0., 0.]))

Dynamic Cuboid

class DynamicCuboid(prim_path: str, name: str = 'dynamic_cube', position: Optional[numpy.ndarray] = None, translation: Optional[numpy.ndarray] = None, orientation: Optional[numpy.ndarray] = None, scale: Optional[numpy.ndarray] = None, visible: Optional[bool] = None, color: Optional[numpy.ndarray] = None, size: Optional[float] = None, visual_material: Optional[omni.isaac.core.materials.visual_material.VisualMaterial] = None, physics_material: Optional[omni.isaac.core.materials.physics_material.PhysicsMaterial] = None, mass: Optional[float] = None, density: Optional[float] = None, linear_velocity: Optional[Sequence[float]] = None, angular_velocity: Optional[Sequence[float]] = None)

High level wrapper to create/encapsulate a dynamic cuboid

Note

Dynamic cuboids (Cube shape) have collisions (Collider API) and rigid body dynamics (Rigid Body API)

Parameters
  • prim_path (str) – prim path of the Prim to encapsulate or create

  • name (str, optional) – shortname to be used as a key by Scene class. Note: needs to be unique if the object is added to the Scene. Defaults to “fixed_cube”.

  • position (Optional[Sequence[float]], optional) – position in the world frame of the prim. shape is (3, ). Defaults to None, which means left unchanged.

  • translation (Optional[Sequence[float]], optional) – translation in the local frame of the prim (with respect to its parent prim). shape is (3, ). Defaults to None, which means left unchanged.

  • orientation (Optional[Sequence[float]], optional) – quaternion orientation in the world/ local frame of the prim (depends if translation or position is specified). quaternion is scalar-first (w, x, y, z). shape is (4, ). Defaults to None, which means left unchanged.

  • scale (Optional[Sequence[float]], optional) – local scale to be applied to the prim’s dimensions. shape is (3, ). Defaults to None, which means left unchanged.

  • visible (bool, optional) – set to false for an invisible prim in the stage while rendering. Defaults to True.

  • color (Optional[np.ndarray], optional) – color of the visual shape. Defaults to None, which means 50% gray

  • size (Optional[float], optional) – length of each cube edge. Defaults to None.

  • visual_material (Optional[VisualMaterial], optional) – visual material to be applied to the held prim. Defaults to None. If not specified, a default visual material will be added.

  • physics_material (Optional[PhysicsMaterial], optional) – physics material to be applied to the held prim. Defaults to None. If not specified, a default physics material will be added.

  • mass (Optional[float], optional) – mass in kg. Defaults to None.

  • density (Optional[float], optional) – density. Defaults to None.

  • linear_velocity (Optional[np.ndarray], optional) – linear velocity in the world frame. Defaults to None.

  • angular_velocity (Optional[np.ndarray], optional) – angular velocity in the world frame. Defaults to None.

Example:

>>> from omni.isaac.core.objects import DynamicCuboid
>>> import numpy as np
>>>
>>> # create a red dynamic cube of mass 1kg at the given path
>>> prim = DynamicCuboid(prim_path="/World/Xform/Cube", color=np.array([1.0, 0.0, 0.0]), mass=1.0)
>>> prim
<omni.isaac.core.objects.cuboid.DynamicCuboid object at 0x7ff14c04d990>
apply_physics_material(physics_material: omni.isaac.core.materials.physics_material.PhysicsMaterial, weaker_than_descendants: bool = False)

Used to apply physics material to the held prim and optionally its descendants.

Parameters
  • physics_material (PhysicsMaterial) – physics material to be applied to the held prim. This where you want to define friction, restitution..etc. Note: if a physics material is not defined, the defaults will be used from PhysX.

  • weaker_than_descendants (bool, optional) – True if the material shouldn’t override the descendants materials, otherwise False. Defaults to False.

Example:

>>> from omni.isaac.core.materials import PhysicsMaterial
>>>
>>> # create a rigid body physical material
>>> material = PhysicsMaterial(
...     prim_path="/World/physics_material/aluminum",  # path to the material prim to create
...     dynamic_friction=0.4,
...     static_friction=1.1,
...     restitution=0.1
... )
>>> prim.apply_physics_material(material)
apply_visual_material(visual_material: omni.isaac.core.materials.visual_material.VisualMaterial, weaker_than_descendants: bool = False) None

Apply visual material to the held prim and optionally its descendants.

Parameters
  • visual_material (VisualMaterial) – visual material to be applied to the held prim. Currently supports PreviewSurface, OmniPBR and OmniGlass.

  • weaker_than_descendants (bool, optional) – True if the material shouldn’t override the descendants materials, otherwise False. Defaults to False.

Example:

>>> from omni.isaac.core.materials import OmniGlass
>>>
>>> # create a dark-red glass visual material
>>> material = OmniGlass(
...     prim_path="/World/material/glass",  # path to the material prim to create
...     ior=1.25,
...     depth=0.001,
...     thin_walled=False,
...     color=np.array([0.5, 0.0, 0.0])
... )
>>> prim.apply_visual_material(material)
disable_rigid_body_physics() None

Disable the rigid body physics

When disabled, the object will not be moved by external forces such as gravity and collisions

Example:

>>> prim.disable_rigid_body_physics()
enable_rigid_body_physics() None

Enable the rigid body physics

When enabled, the object will be moved by external forces such as gravity and collisions

Example:

>>> prim.enable_rigid_body_physics()
property geom: pxr.UsdGeom.Gprim

Returns: UsdGeom.Gprim: USD geometry object encapsulated.

get_angular_velocity()

Get the angular velocity of the rigid body

Returns

current angular velocity of the the rigid prim. Shape (3,).

Return type

np.ndarray

Example:

>>> prim.get_angular_velocity()]
[-0.01727393  0.00827609 -0.00040014]
get_applied_physics_material() omni.isaac.core.materials.physics_material.PhysicsMaterial

Return the current applied physics material in case it was applied using apply_physics_material or not.

Returns

the current applied physics material.

Return type

PhysicsMaterial

Example:

>>> # given a physics material applied
>>> prim.get_applied_physics_material()
<omni.isaac.core.materials.physics_material.PhysicsMaterial object at 0x7fb66c30cd30>
get_applied_visual_material() omni.isaac.core.materials.visual_material.VisualMaterial

Return the current applied visual material in case it was applied using apply_visual_material or it’s one of the following materials that was already applied before: PreviewSurface, OmniPBR and OmniGlass.

Returns

the current applied visual material if its type is currently supported.

Return type

VisualMaterial

Example:

>>> # given a visual material applied
>>> prim.get_applied_visual_material()
<omni.isaac.core.materials.omni_glass.OmniGlass object at 0x7f36263106a0>
get_collision_approximation() str

Get the collision approximation

Approximation

Full name

Description

"none"

Triangle Mesh

The mesh geometry is used directly as a collider without any approximation

"convexDecomposition"

Convex Decomposition

A convex mesh decomposition is performed. This results in a set of convex mesh colliders

"convexHull"

Convex Hull

A convex hull of the mesh is generated and used as the collider

"boundingSphere"

Bounding Sphere

A bounding sphere is computed around the mesh and used as a collider

"boundingCube"

Bounding Cube

An optimally fitting box collider is computed around the mesh

"meshSimplification"

Mesh Simplification

A mesh simplification step is performed, resulting in a simplified triangle mesh collider

"sdf"

SDF Mesh

SDF (Signed-Distance-Field) use high-detail triangle meshes as collision shape

"sphereFill"

Sphere Approximation

A sphere mesh decomposition is performed. This results in a set of sphere colliders

Returns

approximation used for collision

Return type

str

Example:

>>> prim.get_collision_approximation()
none
get_collision_enabled() bool

Check if the Collision API is enabled

Returns

True if the Collision API is enabled. Otherwise False

Return type

bool

Example:

>>> prim.get_collision_enabled()
True
get_contact_force_matrix(dt: float = 1.0) Union[numpy.ndarray, torch.Tensor]

If the object is initialized with filter_paths_expr list, this method returns the contact forces between the prims in the view and the filter prims. i.e., a matrix of dimension (self._contact_view.num_filters, 3) where num_filters is the determined according to the filter_paths_expr parameter.

Parameters

dt (float) – time step multiplier to convert the underlying impulses to forces. If the default value is used then the forces are in fact contact impulses

Returns

Net contact forces of the prims with shape (self._geometry_prim_view._contact_view.num_filters, 3).

Return type

Union[np.ndarray, torch.Tensor]

get_contact_offset() float

Get the contact offset

Shapes whose distance is less than the sum of their contact offset values will generate contacts

Search for Advanced Collision Detection in PhysX docs for more details

Returns

contact offset of the collision shape. Default value is -inf, means default is picked by simulation.

Return type

float

Example:

>>> prim.get_contact_offset()
-inf
get_current_dynamic_state() omni.isaac.core.utils.types.DynamicState

Get the current rigid body state (position, orientation and linear and angular velocities)

Returns

the dynamic state of the rigid body prim

Return type

DynamicState

Example:

>>> # for the example the rigid body is in free fall
>>> state = prim.get_current_dynamic_state()
>>> state
<omni.isaac.core.utils.types.DynamicState object at 0x7f740b36f670>
>>> state.position
[  0.99999857   2.0000017  -74.2862    ]
>>> state.orientation
[ 1.0000000e+00 -2.3961178e-07 -4.9891562e-09  4.9388258e-09]
>>> state.linear_velocity
[  0.        0.      -38.09554]
>>> state.angular_velocity
[0. 0. 0.]
get_default_state() omni.isaac.core.utils.types.DynamicState

Get the default rigid body state (position, orientation and linear and angular velocities)

Returns

returns the default state of the prim that is used after each reset

Return type

DynamicState

Example:

>>> state = prim.get_default_state()
>>> state
<omni.isaac.core.utils.types.DynamicState object at 0x7f7411fcbe20>
>>> state.position
[-7.8622378e-07  1.4450421e-06  1.6135601e-07]
>>> state.orientation
[ 9.9999994e-01 -2.7194994e-07  2.9607077e-07  2.7016510e-08]
>>> state.linear_velocity
[0. 0. 0.]
>>> state.angular_velocity
[0. 0. 0.]
get_density() float

Get the density of the rigid body

Returns

density of the rigid body.

Return type

float

Example:

>>> prim.get_density()
0
get_linear_velocity() numpy.ndarray

Get the linear velocity of the rigid body

Returns

current linear velocity of the the rigid prim. Shape (3,).

Return type

np.ndarray

Example:

>>> prim.get_linear_velocity()
[ 1.0812164e-04  6.1415871e-05 -2.1341663e-04]
get_local_pose() Tuple[numpy.ndarray, numpy.ndarray]

Get prim’s pose with respect to the local frame (the prim’s parent frame)

Returns

first index is the position in the local frame (with shape (3, )). Second index is quaternion orientation (with shape (4, )) in the local frame

Return type

Tuple[np.ndarray, np.ndarray]

Example:

>>> # if the prim is in position (1.0, 0.5, 0.0) with respect to the world frame
>>> position, orientation = prim.get_local_pose()
>>> position
[0. 0. 0.]
>>> orientation
[0. 0. 0.]
get_local_scale() numpy.ndarray

Get prim’s scale with respect to the local frame (the parent’s frame)

Returns

scale applied to the prim’s dimensions in the local frame. shape is (3, ).

Return type

np.ndarray

Example:

>>> prim.get_local_scale()
[1. 1. 1.]
get_mass() float

Get the mass of the rigid body

Returns

mass of the rigid body in kg.

Return type

float

Example:

>>> prim.get_mass()
0
get_min_torsional_patch_radius() float

Get the minimum radius of the contact patch used to apply torsional friction

Search for “Torsional Patch Radius” in PhysX docs for more details

Returns

minimum radius of the contact patch used to apply torsional friction. Allowed range [0, max_float].

Return type

float

Example:

>>> prim.get_min_torsional_patch_radius()
0.0
get_net_contact_forces(dt: float = 1.0) Union[numpy.ndarray, torch.Tensor]

If contact forces of the prims in the view are tracked, this method returns the net contact forces on prims. i.e., a matrix of dimension (1, 3)

Parameters

dt (float) – time step multiplier to convert the underlying impulses to forces. If the default value is used then the forces are in fact contact impulses

Returns

Net contact forces of the prims with shape (3).

Return type

Union[np.ndarray, torch.Tensor]

get_rest_offset() float

Get the rest offset

Two shapes will come to rest at a distance equal to the sum of their rest offset values. If the rest offset is 0, they should converge to touching exactly

Search for Advanced Collision Detection in PhysX docs for more details

Returns

rest offset of the collision shape.

Return type

float

Example:

>>> prim.get_rest_offset()
-inf
get_size() numpy.ndarray

Get the length of each cube edge

Returns

edge length

Return type

float

Example:

>>> prim.get_size()
1.0
get_sleep_threshold() float

Get the threshold for the rigid body to enter a sleep state

Search for Rigid Body Dynamics > Sleeping in PhysX docs for more details

Returns

Mass-normalized kinetic energy threshold below which

an actor may go to sleep. Range: [0, inf) Defaults: 0.00005 * tolerancesSpeed* tolerancesSpeed Units: distance^2 / second^2.

Return type

float

Example:

>>> prim.get_sleep_threshold()
5e-05
get_torsional_patch_radius() float

Get the radius of the contact patch used to apply torsional friction

Search for “Torsional Patch Radius” in PhysX docs for more details

Returns

radius of the contact patch used to apply torsional friction. Allowed range [0, max_float].

Return type

float

Example:

>>> prim.get_torsional_patch_radius()
0.0
get_visibility() bool
Returns

true if the prim is visible in stage. false otherwise.

Return type

bool

Example:

>>> # get the visible state of an visible prim on the stage
>>> prim.get_visibility()
True
get_world_pose() Tuple[numpy.ndarray, numpy.ndarray]

Get prim’s pose with respect to the world’s frame

Returns

first index is the position in the world frame (with shape (3, )). Second index is quaternion orientation (with shape (4, )) in the world frame

Return type

Tuple[np.ndarray, np.ndarray]

Example:

>>> # if the prim is in position (1.0, 0.5, 0.0) with respect to the world frame
>>> position, orientation = prim.get_world_pose()
>>> position
[1.  0.5 0. ]
>>> orientation
[1. 0. 0. 0.]
get_world_scale() numpy.ndarray

Get prim’s scale with respect to the world’s frame

Returns

scale applied to the prim’s dimensions in the world frame. shape is (3, ).

Return type

np.ndarray

Example:

>>> prim.get_world_scale()
[1. 1. 1.]
initialize(physics_sim_view=None) None

Create a physics simulation view if not passed and using PhysX tensor API

Note

If the prim has been added to the world scene (e.g., world.scene.add(prim)), it will be automatically initialized when the world is reset (e.g., world.reset()).

Parameters

physics_sim_view (omni.physics.tensors.SimulationView, optional) – current physics simulation view. Defaults to None.

Example:

>>> prim.initialize()
is_valid() bool

Check if the prim path has a valid USD Prim at it

Returns

True is the current prim path corresponds to a valid prim in stage. False otherwise.

Return type

bool

Example:

>>> # given an existing and valid prim
>>> prims.is_valid()
True
is_visual_material_applied() bool

Check if there is a visual material applied

Returns

True if there is a visual material applied. False otherwise.

Return type

bool

Example:

>>> # given a visual material applied
>>> prim.is_visual_material_applied()
True
property name: Optional[str]

Returns: str: name given to the prim when instantiating it. Otherwise None.

Used to query if the prim is a non root articulation link

Returns

True if the prim itself is a non root link

Return type

bool

Example:

>>> # for a wrapped articulation (where the root prim has the Physics Articulation Root property applied)
>>> prim.non_root_articulation_link
False
post_reset() None

Reset the prim to its default state (position and orientation).

Note

For an articulation, in addition to configuring the root prim’s default position and spatial orientation (defined via the set_default_state method), the joint’s positions, velocities, and efforts (defined via the set_joints_default_state method) are imposed

Example:

>>> prim.post_reset()
property prim: pxr.Usd.Prim

Returns: Usd.Prim: USD Prim object that this object holds.

property prim_path: str

Returns: str: prim path in the stage

set_angular_velocity(velocity: numpy.ndarray) None

Set the angular velocity of the rigid body in stage

Warning

This method will immediately set the articulation state

Parameters

velocity (np.ndarray) – angular velocity to set the rigid prim to. Shape (3,).

Hint

This method belongs to the methods used to set the rigid prim kinematic state:

set_linear_velocity, set_angular_velocity

Example:

>>> prim.set_angular_velocity(np.array([0.0, 0.0, 10.0]))
set_collision_approximation(approximation_type: str) None

Set the collision approximation

Approximation

Full name

Description

"none"

Triangle Mesh

The mesh geometry is used directly as a collider without any approximation

"convexDecomposition"

Convex Decomposition

A convex mesh decomposition is performed. This results in a set of convex mesh colliders

"convexHull"

Convex Hull

A convex hull of the mesh is generated and used as the collider

"boundingSphere"

Bounding Sphere

A bounding sphere is computed around the mesh and used as a collider

"boundingCube"

Bounding Cube

An optimally fitting box collider is computed around the mesh

"meshSimplification"

Mesh Simplification

A mesh simplification step is performed, resulting in a simplified triangle mesh collider

"sdf"

SDF Mesh

SDF (Signed-Distance-Field) use high-detail triangle meshes as collision shape

"sphereFill"

Sphere Approximation

A sphere mesh decomposition is performed. This results in a set of sphere colliders

Note

Use Convex Decomposition or SDF (Signed-Distance-Field) tri-meshes to capture details better

Warning

Switching to Convex Decomposition or SDF (Signed-Distance-Field) will have a simulation performance impact due to higher computational cost

Parameters

approximation_type (str) – approximation used for collision

Example:

>>> prim.set_collision_approximation("convexDecomposition")
set_collision_enabled(enabled: bool) None

Enable/disable the Collision API

Parameters

enabled (bool) – Whether to enable or disable the Collision API

Example:

>>> # disable collisions
>>> prim.set_collision_enabled(False)
set_contact_offset(offset: float) None

Set the contact offset

Shapes whose distance is less than the sum of their contact offset values will generate contacts

Search for Advanced Collision Detection in PhysX docs for more details

Warning

The contact offset must be positive and greater than the rest offset

Parameters

offset (float) – Contact offset of a collision shape. Allowed range [maximum(0, rest_offset), 0]. Default value is -inf, means default is picked by simulation based on the shape extent.

Example:

>>> prim.set_contact_offset(0.02)
set_default_state(position: Optional[Sequence[float]] = None, orientation: Optional[Sequence[float]] = None, linear_velocity: Optional[numpy.ndarray] = None, angular_velocity: Optional[numpy.ndarray] = None) None

Set the default state of the prim (position, orientation and linear and angular velocities), that will be used after each reset

Note

The default states will be set during post-reset (e.g., calling .post_reset() or world.reset() methods)

Parameters
  • position (Optional[Sequence[float]], optional) – position in the world frame of the prim. shape is (3, ). Defaults to None, which means left unchanged.

  • orientation (Optional[Sequence[float]], optional) – quaternion orientation in the world frame of the prim. quaternion is scalar-first (w, x, y, z). shape is (4, ). Defaults to None, which means left unchanged.

  • linear_velocity (np.ndarray) – linear velocity to set the rigid prim to. Shape (3,).

  • angular_velocity (np.ndarray) – angular velocity to set the rigid prim to. Shape (3,).

Example:

>>> prim.set_default_state(
...     position=np.array([1.0, 2.0, 3.0]),
...     orientation=np.array([1.0, 0.0, 0.0, 0.0]),
...     linear_velocity=np.array([0.0, 0.0, 0.0]),
...     angular_velocity=np.array([0.0, 0.0, 0.0])
... )
>>>
>>> prim.post_reset()
set_density(density: float) None

Set the density of the rigid body

Parameters

mass (float) – density of the rigid body.

Example:

>>> prim.set_density(0.9)
set_linear_velocity(velocity: numpy.ndarray)

Set the linear velocity of the rigid body in stage

Warning

This method will immediately set the rigid prim state

Parameters

velocity (np.ndarray) – linear velocity to set the rigid prim to. Shape (3,).

Hint

This method belongs to the methods used to set the rigid prim kinematic state:

set_linear_velocity, set_angular_velocity

Example:

>>> prim.set_linear_velocity(np.array([5.0, 0.0, 0.0]))
set_local_pose(translation: Optional[Sequence[float]] = None, orientation: Optional[Sequence[float]] = None) None

Set prim’s pose with respect to the local frame (the prim’s parent frame).

Warning

This method will change (teleport) the prim pose immediately to the indicated value

Parameters
  • translation (Optional[Sequence[float]], optional) – translation in the local frame of the prim (with respect to its parent prim). shape is (3, ). Defaults to None, which means left unchanged.

  • orientation (Optional[Sequence[float]], optional) – quaternion orientation in the local frame of the prim. quaternion is scalar-first (w, x, y, z). shape is (4, ). Defaults to None, which means left unchanged.

Hint

This method belongs to the methods used to set the prim state

Example:

>>> prim.set_local_pose(translation=np.array([1.0, 0.5, 0.0]), orientation=np.array([1., 0., 0., 0.]))
set_local_scale(scale: Optional[Sequence[float]]) None

Set prim’s scale with respect to the local frame (the prim’s parent frame).

Parameters

scale (Optional[Sequence[float]]) – scale to be applied to the prim’s dimensions. shape is (3, ). Defaults to None, which means left unchanged.

Example:

>>> # scale prim 10 times smaller
>>> prim.set_local_scale(np.array([0.1, 0.1, 0.1]))
set_mass(mass: float) None

Set the mass of the rigid body

Parameters

mass (float) – mass of the rigid body in kg.

Example:

>>> prim.set_mass(1.0)
set_min_torsional_patch_radius(radius: float) None

Set the minimum radius of the contact patch used to apply torsional friction

Search for “Torsional Patch Radius” in PhysX docs for more details

Parameters

radius (float) – minimum radius of the contact patch used to apply torsional friction. Allowed range [0, max_float].

Example:

>>> prim.set_min_torsional_patch_radius(0.05)
set_rest_offset(offset: float) None

Set the rest offset

Two shapes will come to rest at a distance equal to the sum of their rest offset values. If the rest offset is 0, they should converge to touching exactly

Search for Advanced Collision Detection in PhysX docs for more details

Warning

The contact offset must be positive and greater than the rest offset

Parameters

offset (float) – Rest offset of a collision shape. Allowed range [-max_float, contact_offset. Default value is -inf, means default is picked by simulation. For rigid bodies its zero.

Example:

>>> prim.set_rest_offset(0.01)
set_size(size: float) None

Set the length of each cube edge

Parameters

size (float) – edge length

Example:

>>> prim.set_size(2.0)
set_sleep_threshold(threshold: float) None

Set the threshold for the rigid body to enter a sleep state

Search for Rigid Body Dynamics > Sleeping in PhysX docs for more details

Parameters

threshold (float) – Mass-normalized kinetic energy threshold below which an actor may go to sleep. Range: [0, inf) Defaults: 0.00005 * tolerancesSpeed* tolerancesSpeed Units: distance^2 / second^2.

Example:

>>> prim.set_sleep_threshold(1e-5)
set_torsional_patch_radius(radius: float) None

Set the radius of the contact patch used to apply torsional friction

Search for “Torsional Patch Radius” in PhysX docs for more details

Parameters

radius (float) – radius of the contact patch used to apply torsional friction. Allowed range [0, max_float].

Example:

>>> prim.set_torsional_patch_radius(0.1)
set_visibility(visible: bool) None

Set the visibility of the prim in stage

Parameters

visible (bool) – flag to set the visibility of the usd prim in stage.

Example:

>>> # make prim not visible in the stage
>>> prim.set_visibility(visible=False)
set_world_pose(position: Optional[Sequence[float]] = None, orientation: Optional[Sequence[float]] = None) None

Ses prim’s pose with respect to the world’s frame

Warning

This method will change (teleport) the prim pose immediately to the indicated value

Parameters
  • position (Optional[Sequence[float]], optional) – position in the world frame of the prim. shape is (3, ). Defaults to None, which means left unchanged.

  • orientation (Optional[Sequence[float]], optional) – quaternion orientation in the world frame of the prim. quaternion is scalar-first (w, x, y, z). shape is (4, ). Defaults to None, which means left unchanged.

Hint

This method belongs to the methods used to set the prim state

Example:

>>> prim.set_world_pose(position=np.array([1.0, 0.5, 0.0]), orientation=np.array([1., 0., 0., 0.]))

Dynamic Cylinder

class DynamicCylinder(prim_path: str, name: str = 'dynamic_cylinder', position: Optional[numpy.ndarray] = None, translation: Optional[numpy.ndarray] = None, orientation: Optional[numpy.ndarray] = None, scale: Optional[numpy.ndarray] = None, visible: Optional[bool] = None, color: Optional[numpy.ndarray] = None, radius: Optional[numpy.ndarray] = None, height: Optional[numpy.ndarray] = None, visual_material: Optional[omni.isaac.core.materials.visual_material.VisualMaterial] = None, physics_material: Optional[omni.isaac.core.materials.physics_material.PhysicsMaterial] = None, mass: Optional[float] = None, density: Optional[float] = None, linear_velocity: Optional[Sequence[float]] = None, angular_velocity: Optional[Sequence[float]] = None)

High level wrapper to create/encapsulate a dynamic cylinder

Note

Dynamic cylinders (Cylinder shape) have collisions (Collider API) and rigid body dynamics (Rigid Body API)

Parameters
  • prim_path (str) – prim path of the Prim to encapsulate or create

  • name (str, optional) – shortname to be used as a key by Scene class. Note: needs to be unique if the object is added to the Scene. Defaults to “dynamic_cylinder”.

  • position (Optional[Sequence[float]], optional) – position in the world frame of the prim. shape is (3, ). Defaults to None, which means left unchanged.

  • translation (Optional[Sequence[float]], optional) – translation in the local frame of the prim (with respect to its parent prim). shape is (3, ). Defaults to None, which means left unchanged.

  • orientation (Optional[Sequence[float]], optional) – quaternion orientation in the world/ local frame of the prim (depends if translation or position is specified). quaternion is scalar-first (w, x, y, z). shape is (4, ). Defaults to None, which means left unchanged.

  • scale (Optional[Sequence[float]], optional) – local scale to be applied to the prim’s dimensions. shape is (3, ). Defaults to None, which means left unchanged.

  • visible (bool, optional) – set to false for an invisible prim in the stage while rendering. Defaults to True.

  • color (Optional[np.ndarray], optional) – color of the visual shape. Defaults to None, which means 50% gray

  • radius (Optional[float], optional) – base radius. Defaults to None.

  • height (Optional[float], optional) – cylinder height. Defaults to None.

  • visual_material (Optional[VisualMaterial], optional) – visual material to be applied to the held prim. Defaults to None. If not specified, a default visual material will be added.

  • physics_material (Optional[PhysicsMaterial], optional) – physics material to be applied to the held prim. Defaults to None. If not specified, a default physics material will be added.

  • mass (Optional[float], optional) – mass in kg. Defaults to None.

  • density (Optional[float], optional) – density. Defaults to None.

  • linear_velocity (Optional[np.ndarray], optional) – linear velocity in the world frame. Defaults to None.

  • angular_velocity (Optional[np.ndarray], optional) – angular velocity in the world frame. Defaults to None.

Example:

>>> from omni.isaac.core.objects import DynamicCylinder
>>> import numpy as np
>>>
>>> # create a red fixed cylinder of mass 1kg at the given path
>>> prim = DynamicCylinder(
...     prim_path="/World/Xform/Cylinder",
...     radius=0.5,
...     height=1.0,
...     color=np.array([1.0, 0.0, 0.0]),
...     mass=1.0
... )
>>> prim
<omni.isaac.core.objects.cylinder.DynamicCylinder object at 0x7f4e8f5c4a60>
apply_physics_material(physics_material: omni.isaac.core.materials.physics_material.PhysicsMaterial, weaker_than_descendants: bool = False)

Used to apply physics material to the held prim and optionally its descendants.

Parameters
  • physics_material (PhysicsMaterial) – physics material to be applied to the held prim. This where you want to define friction, restitution..etc. Note: if a physics material is not defined, the defaults will be used from PhysX.

  • weaker_than_descendants (bool, optional) – True if the material shouldn’t override the descendants materials, otherwise False. Defaults to False.

Example:

>>> from omni.isaac.core.materials import PhysicsMaterial
>>>
>>> # create a rigid body physical material
>>> material = PhysicsMaterial(
...     prim_path="/World/physics_material/aluminum",  # path to the material prim to create
...     dynamic_friction=0.4,
...     static_friction=1.1,
...     restitution=0.1
... )
>>> prim.apply_physics_material(material)
apply_visual_material(visual_material: omni.isaac.core.materials.visual_material.VisualMaterial, weaker_than_descendants: bool = False) None

Apply visual material to the held prim and optionally its descendants.

Parameters
  • visual_material (VisualMaterial) – visual material to be applied to the held prim. Currently supports PreviewSurface, OmniPBR and OmniGlass.

  • weaker_than_descendants (bool, optional) – True if the material shouldn’t override the descendants materials, otherwise False. Defaults to False.

Example:

>>> from omni.isaac.core.materials import OmniGlass
>>>
>>> # create a dark-red glass visual material
>>> material = OmniGlass(
...     prim_path="/World/material/glass",  # path to the material prim to create
...     ior=1.25,
...     depth=0.001,
...     thin_walled=False,
...     color=np.array([0.5, 0.0, 0.0])
... )
>>> prim.apply_visual_material(material)
disable_rigid_body_physics() None

Disable the rigid body physics

When disabled, the object will not be moved by external forces such as gravity and collisions

Example:

>>> prim.disable_rigid_body_physics()
enable_rigid_body_physics() None

Enable the rigid body physics

When enabled, the object will be moved by external forces such as gravity and collisions

Example:

>>> prim.enable_rigid_body_physics()
property geom: pxr.UsdGeom.Gprim

Returns: UsdGeom.Gprim: USD geometry object encapsulated.

get_angular_velocity()

Get the angular velocity of the rigid body

Returns

current angular velocity of the the rigid prim. Shape (3,).

Return type

np.ndarray

Example:

>>> prim.get_angular_velocity()]
[-0.01727393  0.00827609 -0.00040014]
get_applied_physics_material() omni.isaac.core.materials.physics_material.PhysicsMaterial

Return the current applied physics material in case it was applied using apply_physics_material or not.

Returns

the current applied physics material.

Return type

PhysicsMaterial

Example:

>>> # given a physics material applied
>>> prim.get_applied_physics_material()
<omni.isaac.core.materials.physics_material.PhysicsMaterial object at 0x7fb66c30cd30>
get_applied_visual_material() omni.isaac.core.materials.visual_material.VisualMaterial

Return the current applied visual material in case it was applied using apply_visual_material or it’s one of the following materials that was already applied before: PreviewSurface, OmniPBR and OmniGlass.

Returns

the current applied visual material if its type is currently supported.

Return type

VisualMaterial

Example:

>>> # given a visual material applied
>>> prim.get_applied_visual_material()
<omni.isaac.core.materials.omni_glass.OmniGlass object at 0x7f36263106a0>
get_collision_approximation() str

Get the collision approximation

Approximation

Full name

Description

"none"

Triangle Mesh

The mesh geometry is used directly as a collider without any approximation

"convexDecomposition"

Convex Decomposition

A convex mesh decomposition is performed. This results in a set of convex mesh colliders

"convexHull"

Convex Hull

A convex hull of the mesh is generated and used as the collider

"boundingSphere"

Bounding Sphere

A bounding sphere is computed around the mesh and used as a collider

"boundingCube"

Bounding Cube

An optimally fitting box collider is computed around the mesh

"meshSimplification"

Mesh Simplification

A mesh simplification step is performed, resulting in a simplified triangle mesh collider

"sdf"

SDF Mesh

SDF (Signed-Distance-Field) use high-detail triangle meshes as collision shape

"sphereFill"

Sphere Approximation

A sphere mesh decomposition is performed. This results in a set of sphere colliders

Returns

approximation used for collision

Return type

str

Example:

>>> prim.get_collision_approximation()
none
get_collision_enabled() bool

Check if the Collision API is enabled

Returns

True if the Collision API is enabled. Otherwise False

Return type

bool

Example:

>>> prim.get_collision_enabled()
True
get_contact_force_matrix(dt: float = 1.0) Union[numpy.ndarray, torch.Tensor]

If the object is initialized with filter_paths_expr list, this method returns the contact forces between the prims in the view and the filter prims. i.e., a matrix of dimension (self._contact_view.num_filters, 3) where num_filters is the determined according to the filter_paths_expr parameter.

Parameters

dt (float) – time step multiplier to convert the underlying impulses to forces. If the default value is used then the forces are in fact contact impulses

Returns

Net contact forces of the prims with shape (self._geometry_prim_view._contact_view.num_filters, 3).

Return type

Union[np.ndarray, torch.Tensor]

get_contact_offset() float

Get the contact offset

Shapes whose distance is less than the sum of their contact offset values will generate contacts

Search for Advanced Collision Detection in PhysX docs for more details

Returns

contact offset of the collision shape. Default value is -inf, means default is picked by simulation.

Return type

float

Example:

>>> prim.get_contact_offset()
-inf
get_current_dynamic_state() omni.isaac.core.utils.types.DynamicState

Get the current rigid body state (position, orientation and linear and angular velocities)

Returns

the dynamic state of the rigid body prim

Return type

DynamicState

Example:

>>> # for the example the rigid body is in free fall
>>> state = prim.get_current_dynamic_state()
>>> state
<omni.isaac.core.utils.types.DynamicState object at 0x7f740b36f670>
>>> state.position
[  0.99999857   2.0000017  -74.2862    ]
>>> state.orientation
[ 1.0000000e+00 -2.3961178e-07 -4.9891562e-09  4.9388258e-09]
>>> state.linear_velocity
[  0.        0.      -38.09554]
>>> state.angular_velocity
[0. 0. 0.]
get_default_state() omni.isaac.core.utils.types.DynamicState

Get the default rigid body state (position, orientation and linear and angular velocities)

Returns

returns the default state of the prim that is used after each reset

Return type

DynamicState

Example:

>>> state = prim.get_default_state()
>>> state
<omni.isaac.core.utils.types.DynamicState object at 0x7f7411fcbe20>
>>> state.position
[-7.8622378e-07  1.4450421e-06  1.6135601e-07]
>>> state.orientation
[ 9.9999994e-01 -2.7194994e-07  2.9607077e-07  2.7016510e-08]
>>> state.linear_velocity
[0. 0. 0.]
>>> state.angular_velocity
[0. 0. 0.]
get_density() float

Get the density of the rigid body

Returns

density of the rigid body.

Return type

float

Example:

>>> prim.get_density()
0
get_height() float

Get the cylinder height

Returns

cylinder height

Return type

float

Example:

>>> prim.get_height()
1.0
get_linear_velocity() numpy.ndarray

Get the linear velocity of the rigid body

Returns

current linear velocity of the the rigid prim. Shape (3,).

Return type

np.ndarray

Example:

>>> prim.get_linear_velocity()
[ 1.0812164e-04  6.1415871e-05 -2.1341663e-04]
get_local_pose() Tuple[numpy.ndarray, numpy.ndarray]

Get prim’s pose with respect to the local frame (the prim’s parent frame)

Returns

first index is the position in the local frame (with shape (3, )). Second index is quaternion orientation (with shape (4, )) in the local frame

Return type

Tuple[np.ndarray, np.ndarray]

Example:

>>> # if the prim is in position (1.0, 0.5, 0.0) with respect to the world frame
>>> position, orientation = prim.get_local_pose()
>>> position
[0. 0. 0.]
>>> orientation
[0. 0. 0.]
get_local_scale() numpy.ndarray

Get prim’s scale with respect to the local frame (the parent’s frame)

Returns

scale applied to the prim’s dimensions in the local frame. shape is (3, ).

Return type

np.ndarray

Example:

>>> prim.get_local_scale()
[1. 1. 1.]
get_mass() float

Get the mass of the rigid body

Returns

mass of the rigid body in kg.

Return type

float

Example:

>>> prim.get_mass()
0
get_min_torsional_patch_radius() float

Get the minimum radius of the contact patch used to apply torsional friction

Search for “Torsional Patch Radius” in PhysX docs for more details

Returns

minimum radius of the contact patch used to apply torsional friction. Allowed range [0, max_float].

Return type

float

Example:

>>> prim.get_min_torsional_patch_radius()
0.0
get_net_contact_forces(dt: float = 1.0) Union[numpy.ndarray, torch.Tensor]

If contact forces of the prims in the view are tracked, this method returns the net contact forces on prims. i.e., a matrix of dimension (1, 3)

Parameters

dt (float) – time step multiplier to convert the underlying impulses to forces. If the default value is used then the forces are in fact contact impulses

Returns

Net contact forces of the prims with shape (3).

Return type

Union[np.ndarray, torch.Tensor]

get_radius() float

Get the base radius

Returns

base radius

Return type

float

Example:

>>> prim.get_radius()
0.5
get_rest_offset() float

Get the rest offset

Two shapes will come to rest at a distance equal to the sum of their rest offset values. If the rest offset is 0, they should converge to touching exactly

Search for Advanced Collision Detection in PhysX docs for more details

Returns

rest offset of the collision shape.

Return type

float

Example:

>>> prim.get_rest_offset()
-inf
get_sleep_threshold() float

Get the threshold for the rigid body to enter a sleep state

Search for Rigid Body Dynamics > Sleeping in PhysX docs for more details

Returns

Mass-normalized kinetic energy threshold below which

an actor may go to sleep. Range: [0, inf) Defaults: 0.00005 * tolerancesSpeed* tolerancesSpeed Units: distance^2 / second^2.

Return type

float

Example:

>>> prim.get_sleep_threshold()
5e-05
get_torsional_patch_radius() float

Get the radius of the contact patch used to apply torsional friction

Search for “Torsional Patch Radius” in PhysX docs for more details

Returns

radius of the contact patch used to apply torsional friction. Allowed range [0, max_float].

Return type

float

Example:

>>> prim.get_torsional_patch_radius()
0.0
get_visibility() bool
Returns

true if the prim is visible in stage. false otherwise.

Return type

bool

Example:

>>> # get the visible state of an visible prim on the stage
>>> prim.get_visibility()
True
get_world_pose() Tuple[numpy.ndarray, numpy.ndarray]

Get prim’s pose with respect to the world’s frame

Returns

first index is the position in the world frame (with shape (3, )). Second index is quaternion orientation (with shape (4, )) in the world frame

Return type

Tuple[np.ndarray, np.ndarray]

Example:

>>> # if the prim is in position (1.0, 0.5, 0.0) with respect to the world frame
>>> position, orientation = prim.get_world_pose()
>>> position
[1.  0.5 0. ]
>>> orientation
[1. 0. 0. 0.]
get_world_scale() numpy.ndarray

Get prim’s scale with respect to the world’s frame

Returns

scale applied to the prim’s dimensions in the world frame. shape is (3, ).

Return type

np.ndarray

Example:

>>> prim.get_world_scale()
[1. 1. 1.]
initialize(physics_sim_view=None) None

Create a physics simulation view if not passed and using PhysX tensor API

Note

If the prim has been added to the world scene (e.g., world.scene.add(prim)), it will be automatically initialized when the world is reset (e.g., world.reset()).

Parameters

physics_sim_view (omni.physics.tensors.SimulationView, optional) – current physics simulation view. Defaults to None.

Example:

>>> prim.initialize()
is_valid() bool

Check if the prim path has a valid USD Prim at it

Returns

True is the current prim path corresponds to a valid prim in stage. False otherwise.

Return type

bool

Example:

>>> # given an existing and valid prim
>>> prims.is_valid()
True
is_visual_material_applied() bool

Check if there is a visual material applied

Returns

True if there is a visual material applied. False otherwise.

Return type

bool

Example:

>>> # given a visual material applied
>>> prim.is_visual_material_applied()
True
property name: Optional[str]

Returns: str: name given to the prim when instantiating it. Otherwise None.

Used to query if the prim is a non root articulation link

Returns

True if the prim itself is a non root link

Return type

bool

Example:

>>> # for a wrapped articulation (where the root prim has the Physics Articulation Root property applied)
>>> prim.non_root_articulation_link
False
post_reset() None

Reset the prim to its default state (position and orientation).

Note

For an articulation, in addition to configuring the root prim’s default position and spatial orientation (defined via the set_default_state method), the joint’s positions, velocities, and efforts (defined via the set_joints_default_state method) are imposed

Example:

>>> prim.post_reset()
property prim: pxr.Usd.Prim

Returns: Usd.Prim: USD Prim object that this object holds.

property prim_path: str

Returns: str: prim path in the stage

set_angular_velocity(velocity: numpy.ndarray) None

Set the angular velocity of the rigid body in stage

Warning

This method will immediately set the articulation state

Parameters

velocity (np.ndarray) – angular velocity to set the rigid prim to. Shape (3,).

Hint

This method belongs to the methods used to set the rigid prim kinematic state:

set_linear_velocity, set_angular_velocity

Example:

>>> prim.set_angular_velocity(np.array([0.0, 0.0, 10.0]))
set_collision_approximation(approximation_type: str) None

Set the collision approximation

Approximation

Full name

Description

"none"

Triangle Mesh

The mesh geometry is used directly as a collider without any approximation

"convexDecomposition"

Convex Decomposition

A convex mesh decomposition is performed. This results in a set of convex mesh colliders

"convexHull"

Convex Hull

A convex hull of the mesh is generated and used as the collider

"boundingSphere"

Bounding Sphere

A bounding sphere is computed around the mesh and used as a collider

"boundingCube"

Bounding Cube

An optimally fitting box collider is computed around the mesh

"meshSimplification"

Mesh Simplification

A mesh simplification step is performed, resulting in a simplified triangle mesh collider

"sdf"

SDF Mesh

SDF (Signed-Distance-Field) use high-detail triangle meshes as collision shape

"sphereFill"

Sphere Approximation

A sphere mesh decomposition is performed. This results in a set of sphere colliders

Note

Use Convex Decomposition or SDF (Signed-Distance-Field) tri-meshes to capture details better

Warning

Switching to Convex Decomposition or SDF (Signed-Distance-Field) will have a simulation performance impact due to higher computational cost

Parameters

approximation_type (str) – approximation used for collision

Example:

>>> prim.set_collision_approximation("convexDecomposition")
set_collision_enabled(enabled: bool) None

Enable/disable the Collision API

Parameters

enabled (bool) – Whether to enable or disable the Collision API

Example:

>>> # disable collisions
>>> prim.set_collision_enabled(False)
set_contact_offset(offset: float) None

Set the contact offset

Shapes whose distance is less than the sum of their contact offset values will generate contacts

Search for Advanced Collision Detection in PhysX docs for more details

Warning

The contact offset must be positive and greater than the rest offset

Parameters

offset (float) – Contact offset of a collision shape. Allowed range [maximum(0, rest_offset), 0]. Default value is -inf, means default is picked by simulation based on the shape extent.

Example:

>>> prim.set_contact_offset(0.02)
set_default_state(position: Optional[Sequence[float]] = None, orientation: Optional[Sequence[float]] = None, linear_velocity: Optional[numpy.ndarray] = None, angular_velocity: Optional[numpy.ndarray] = None) None

Set the default state of the prim (position, orientation and linear and angular velocities), that will be used after each reset

Note

The default states will be set during post-reset (e.g., calling .post_reset() or world.reset() methods)

Parameters
  • position (Optional[Sequence[float]], optional) – position in the world frame of the prim. shape is (3, ). Defaults to None, which means left unchanged.

  • orientation (Optional[Sequence[float]], optional) – quaternion orientation in the world frame of the prim. quaternion is scalar-first (w, x, y, z). shape is (4, ). Defaults to None, which means left unchanged.

  • linear_velocity (np.ndarray) – linear velocity to set the rigid prim to. Shape (3,).

  • angular_velocity (np.ndarray) – angular velocity to set the rigid prim to. Shape (3,).

Example:

>>> prim.set_default_state(
...     position=np.array([1.0, 2.0, 3.0]),
...     orientation=np.array([1.0, 0.0, 0.0, 0.0]),
...     linear_velocity=np.array([0.0, 0.0, 0.0]),
...     angular_velocity=np.array([0.0, 0.0, 0.0])
... )
>>>
>>> prim.post_reset()
set_density(density: float) None

Set the density of the rigid body

Parameters

mass (float) – density of the rigid body.

Example:

>>> prim.set_density(0.9)
set_height(height: float) None

Set the cylinder height

Parameters

height (float) – cylinder height

Example:

>>> prim.set_height(2.0)
set_linear_velocity(velocity: numpy.ndarray)

Set the linear velocity of the rigid body in stage

Warning

This method will immediately set the rigid prim state

Parameters

velocity (np.ndarray) – linear velocity to set the rigid prim to. Shape (3,).

Hint

This method belongs to the methods used to set the rigid prim kinematic state:

set_linear_velocity, set_angular_velocity

Example:

>>> prim.set_linear_velocity(np.array([5.0, 0.0, 0.0]))
set_local_pose(translation: Optional[Sequence[float]] = None, orientation: Optional[Sequence[float]] = None) None

Set prim’s pose with respect to the local frame (the prim’s parent frame).

Warning

This method will change (teleport) the prim pose immediately to the indicated value

Parameters
  • translation (Optional[Sequence[float]], optional) – translation in the local frame of the prim (with respect to its parent prim). shape is (3, ). Defaults to None, which means left unchanged.

  • orientation (Optional[Sequence[float]], optional) – quaternion orientation in the local frame of the prim. quaternion is scalar-first (w, x, y, z). shape is (4, ). Defaults to None, which means left unchanged.

Hint

This method belongs to the methods used to set the prim state

Example:

>>> prim.set_local_pose(translation=np.array([1.0, 0.5, 0.0]), orientation=np.array([1., 0., 0., 0.]))
set_local_scale(scale: Optional[Sequence[float]]) None

Set prim’s scale with respect to the local frame (the prim’s parent frame).

Parameters

scale (Optional[Sequence[float]]) – scale to be applied to the prim’s dimensions. shape is (3, ). Defaults to None, which means left unchanged.

Example:

>>> # scale prim 10 times smaller
>>> prim.set_local_scale(np.array([0.1, 0.1, 0.1]))
set_mass(mass: float) None

Set the mass of the rigid body

Parameters

mass (float) – mass of the rigid body in kg.

Example:

>>> prim.set_mass(1.0)
set_min_torsional_patch_radius(radius: float) None

Set the minimum radius of the contact patch used to apply torsional friction

Search for “Torsional Patch Radius” in PhysX docs for more details

Parameters

radius (float) – minimum radius of the contact patch used to apply torsional friction. Allowed range [0, max_float].

Example:

>>> prim.set_min_torsional_patch_radius(0.05)
set_radius(radius: float) None

Set the base radius

Parameters

radius (float) – base radius

Example:

>>> prim.set_radius(1.0)
set_rest_offset(offset: float) None

Set the rest offset

Two shapes will come to rest at a distance equal to the sum of their rest offset values. If the rest offset is 0, they should converge to touching exactly

Search for Advanced Collision Detection in PhysX docs for more details

Warning

The contact offset must be positive and greater than the rest offset

Parameters

offset (float) – Rest offset of a collision shape. Allowed range [-max_float, contact_offset. Default value is -inf, means default is picked by simulation. For rigid bodies its zero.

Example:

>>> prim.set_rest_offset(0.01)
set_sleep_threshold(threshold: float) None

Set the threshold for the rigid body to enter a sleep state

Search for Rigid Body Dynamics > Sleeping in PhysX docs for more details

Parameters

threshold (float) – Mass-normalized kinetic energy threshold below which an actor may go to sleep. Range: [0, inf) Defaults: 0.00005 * tolerancesSpeed* tolerancesSpeed Units: distance^2 / second^2.

Example:

>>> prim.set_sleep_threshold(1e-5)
set_torsional_patch_radius(radius: float) None

Set the radius of the contact patch used to apply torsional friction

Search for “Torsional Patch Radius” in PhysX docs for more details

Parameters

radius (float) – radius of the contact patch used to apply torsional friction. Allowed range [0, max_float].

Example:

>>> prim.set_torsional_patch_radius(0.1)
set_visibility(visible: bool) None

Set the visibility of the prim in stage

Parameters

visible (bool) – flag to set the visibility of the usd prim in stage.

Example:

>>> # make prim not visible in the stage
>>> prim.set_visibility(visible=False)
set_world_pose(position: Optional[Sequence[float]] = None, orientation: Optional[Sequence[float]] = None) None

Ses prim’s pose with respect to the world’s frame

Warning

This method will change (teleport) the prim pose immediately to the indicated value

Parameters
  • position (Optional[Sequence[float]], optional) – position in the world frame of the prim. shape is (3, ). Defaults to None, which means left unchanged.

  • orientation (Optional[Sequence[float]], optional) – quaternion orientation in the world frame of the prim. quaternion is scalar-first (w, x, y, z). shape is (4, ). Defaults to None, which means left unchanged.

Hint

This method belongs to the methods used to set the prim state

Example:

>>> prim.set_world_pose(position=np.array([1.0, 0.5, 0.0]), orientation=np.array([1., 0., 0., 0.]))

Dynamic Sphere

class DynamicSphere(prim_path: str, name: str = 'dynamic_sphere', position: Optional[numpy.ndarray] = None, translation: Optional[numpy.ndarray] = None, orientation: Optional[numpy.ndarray] = None, scale: Optional[numpy.ndarray] = None, visible: Optional[bool] = None, color: Optional[numpy.ndarray] = None, radius: Optional[numpy.ndarray] = None, visual_material: Optional[omni.isaac.core.materials.visual_material.VisualMaterial] = None, physics_material: Optional[omni.isaac.core.materials.physics_material.PhysicsMaterial] = None, mass: Optional[float] = None, density: Optional[float] = None, linear_velocity: Optional[Sequence[float]] = None, angular_velocity: Optional[Sequence[float]] = None)

High level wrapper to create/encapsulate a dynamic sphere

Note

Dynamic spheres (Sphere shape) have collisions (Collider API) and rigid body dynamics (Rigid Body API)

Parameters
  • prim_path (str) – prim path of the Prim to encapsulate or create

  • name (str, optional) – shortname to be used as a key by Scene class. Note: needs to be unique if the object is added to the Scene. Defaults to “dynamic_sphere”.

  • position (Optional[Sequence[float]], optional) – position in the world frame of the prim. shape is (3, ). Defaults to None, which means left unchanged.

  • translation (Optional[Sequence[float]], optional) – translation in the local frame of the prim (with respect to its parent prim). shape is (3, ). Defaults to None, which means left unchanged.

  • orientation (Optional[Sequence[float]], optional) – quaternion orientation in the world/ local frame of the prim (depends if translation or position is specified). quaternion is scalar-first (w, x, y, z). shape is (4, ). Defaults to None, which means left unchanged.

  • scale (Optional[Sequence[float]], optional) – local scale to be applied to the prim’s dimensions. shape is (3, ). Defaults to None, which means left unchanged.

  • visible (bool, optional) – set to false for an invisible prim in the stage while rendering. Defaults to True.

  • color (Optional[np.ndarray], optional) – color of the visual shape. Defaults to None, which means 50% gray

  • radius (Optional[float], optional) – sphere radius. Defaults to None.

  • visual_material (Optional[VisualMaterial], optional) – visual material to be applied to the held prim. Defaults to None. If not specified, a default visual material will be added.

  • physics_material (Optional[PhysicsMaterial], optional) – physics material to be applied to the held prim. Defaults to None. If not specified, a default physics material will be added.

  • mass (Optional[float], optional) – mass in kg. Defaults to None.

  • density (Optional[float], optional) – density. Defaults to None.

  • linear_velocity (Optional[np.ndarray], optional) – linear velocity in the world frame. Defaults to None.

  • angular_velocity (Optional[np.ndarray], optional) – angular velocity in the world frame. Defaults to None.

Example:

>>> from omni.isaac.core.objects import DynamicSphere
>>> import numpy as np
>>>
>>> # create a red dynamic sphere of mass 1kg at the given path
>>> prim = DynamicSphere(prim_path="/World/Xform/Sphere", color=np.array([1.0, 0.0, 0.0]), mass=1.0)
>>> prim
<omni.isaac.core.objects.sphere.DynamicSphere object at 0x7f4deaf8f010>
apply_physics_material(physics_material: omni.isaac.core.materials.physics_material.PhysicsMaterial, weaker_than_descendants: bool = False)

Used to apply physics material to the held prim and optionally its descendants.

Parameters
  • physics_material (PhysicsMaterial) – physics material to be applied to the held prim. This where you want to define friction, restitution..etc. Note: if a physics material is not defined, the defaults will be used from PhysX.

  • weaker_than_descendants (bool, optional) – True if the material shouldn’t override the descendants materials, otherwise False. Defaults to False.

Example:

>>> from omni.isaac.core.materials import PhysicsMaterial
>>>
>>> # create a rigid body physical material
>>> material = PhysicsMaterial(
...     prim_path="/World/physics_material/aluminum",  # path to the material prim to create
...     dynamic_friction=0.4,
...     static_friction=1.1,
...     restitution=0.1
... )
>>> prim.apply_physics_material(material)
apply_visual_material(visual_material: omni.isaac.core.materials.visual_material.VisualMaterial, weaker_than_descendants: bool = False) None

Apply visual material to the held prim and optionally its descendants.

Parameters
  • visual_material (VisualMaterial) – visual material to be applied to the held prim. Currently supports PreviewSurface, OmniPBR and OmniGlass.

  • weaker_than_descendants (bool, optional) – True if the material shouldn’t override the descendants materials, otherwise False. Defaults to False.

Example:

>>> from omni.isaac.core.materials import OmniGlass
>>>
>>> # create a dark-red glass visual material
>>> material = OmniGlass(
...     prim_path="/World/material/glass",  # path to the material prim to create
...     ior=1.25,
...     depth=0.001,
...     thin_walled=False,
...     color=np.array([0.5, 0.0, 0.0])
... )
>>> prim.apply_visual_material(material)
disable_rigid_body_physics() None

Disable the rigid body physics

When disabled, the object will not be moved by external forces such as gravity and collisions

Example:

>>> prim.disable_rigid_body_physics()
enable_rigid_body_physics() None

Enable the rigid body physics

When enabled, the object will be moved by external forces such as gravity and collisions

Example:

>>> prim.enable_rigid_body_physics()
property geom: pxr.UsdGeom.Gprim

Returns: UsdGeom.Gprim: USD geometry object encapsulated.

get_angular_velocity()

Get the angular velocity of the rigid body

Returns

current angular velocity of the the rigid prim. Shape (3,).

Return type

np.ndarray

Example:

>>> prim.get_angular_velocity()]
[-0.01727393  0.00827609 -0.00040014]
get_applied_physics_material() omni.isaac.core.materials.physics_material.PhysicsMaterial

Return the current applied physics material in case it was applied using apply_physics_material or not.

Returns

the current applied physics material.

Return type

PhysicsMaterial

Example:

>>> # given a physics material applied
>>> prim.get_applied_physics_material()
<omni.isaac.core.materials.physics_material.PhysicsMaterial object at 0x7fb66c30cd30>
get_applied_visual_material() omni.isaac.core.materials.visual_material.VisualMaterial

Return the current applied visual material in case it was applied using apply_visual_material or it’s one of the following materials that was already applied before: PreviewSurface, OmniPBR and OmniGlass.

Returns

the current applied visual material if its type is currently supported.

Return type

VisualMaterial

Example:

>>> # given a visual material applied
>>> prim.get_applied_visual_material()
<omni.isaac.core.materials.omni_glass.OmniGlass object at 0x7f36263106a0>
get_collision_approximation() str

Get the collision approximation

Approximation

Full name

Description

"none"

Triangle Mesh

The mesh geometry is used directly as a collider without any approximation

"convexDecomposition"

Convex Decomposition

A convex mesh decomposition is performed. This results in a set of convex mesh colliders

"convexHull"

Convex Hull

A convex hull of the mesh is generated and used as the collider

"boundingSphere"

Bounding Sphere

A bounding sphere is computed around the mesh and used as a collider

"boundingCube"

Bounding Cube

An optimally fitting box collider is computed around the mesh

"meshSimplification"

Mesh Simplification

A mesh simplification step is performed, resulting in a simplified triangle mesh collider

"sdf"

SDF Mesh

SDF (Signed-Distance-Field) use high-detail triangle meshes as collision shape

"sphereFill"

Sphere Approximation

A sphere mesh decomposition is performed. This results in a set of sphere colliders

Returns

approximation used for collision

Return type

str

Example:

>>> prim.get_collision_approximation()
none
get_collision_enabled() bool

Check if the Collision API is enabled

Returns

True if the Collision API is enabled. Otherwise False

Return type

bool

Example:

>>> prim.get_collision_enabled()
True
get_contact_force_matrix(dt: float = 1.0) Union[numpy.ndarray, torch.Tensor]

If the object is initialized with filter_paths_expr list, this method returns the contact forces between the prims in the view and the filter prims. i.e., a matrix of dimension (self._contact_view.num_filters, 3) where num_filters is the determined according to the filter_paths_expr parameter.

Parameters

dt (float) – time step multiplier to convert the underlying impulses to forces. If the default value is used then the forces are in fact contact impulses

Returns

Net contact forces of the prims with shape (self._geometry_prim_view._contact_view.num_filters, 3).

Return type

Union[np.ndarray, torch.Tensor]

get_contact_offset() float

Get the contact offset

Shapes whose distance is less than the sum of their contact offset values will generate contacts

Search for Advanced Collision Detection in PhysX docs for more details

Returns

contact offset of the collision shape. Default value is -inf, means default is picked by simulation.

Return type

float

Example:

>>> prim.get_contact_offset()
-inf
get_current_dynamic_state() omni.isaac.core.utils.types.DynamicState

Get the current rigid body state (position, orientation and linear and angular velocities)

Returns

the dynamic state of the rigid body prim

Return type

DynamicState

Example:

>>> # for the example the rigid body is in free fall
>>> state = prim.get_current_dynamic_state()
>>> state
<omni.isaac.core.utils.types.DynamicState object at 0x7f740b36f670>
>>> state.position
[  0.99999857   2.0000017  -74.2862    ]
>>> state.orientation
[ 1.0000000e+00 -2.3961178e-07 -4.9891562e-09  4.9388258e-09]
>>> state.linear_velocity
[  0.        0.      -38.09554]
>>> state.angular_velocity
[0. 0. 0.]
get_default_state() omni.isaac.core.utils.types.DynamicState

Get the default rigid body state (position, orientation and linear and angular velocities)

Returns

returns the default state of the prim that is used after each reset

Return type

DynamicState

Example:

>>> state = prim.get_default_state()
>>> state
<omni.isaac.core.utils.types.DynamicState object at 0x7f7411fcbe20>
>>> state.position
[-7.8622378e-07  1.4450421e-06  1.6135601e-07]
>>> state.orientation
[ 9.9999994e-01 -2.7194994e-07  2.9607077e-07  2.7016510e-08]
>>> state.linear_velocity
[0. 0. 0.]
>>> state.angular_velocity
[0. 0. 0.]
get_density() float

Get the density of the rigid body

Returns

density of the rigid body.

Return type

float

Example:

>>> prim.get_density()
0
get_linear_velocity() numpy.ndarray

Get the linear velocity of the rigid body

Returns

current linear velocity of the the rigid prim. Shape (3,).

Return type

np.ndarray

Example:

>>> prim.get_linear_velocity()
[ 1.0812164e-04  6.1415871e-05 -2.1341663e-04]
get_local_pose() Tuple[numpy.ndarray, numpy.ndarray]

Get prim’s pose with respect to the local frame (the prim’s parent frame)

Returns

first index is the position in the local frame (with shape (3, )). Second index is quaternion orientation (with shape (4, )) in the local frame

Return type

Tuple[np.ndarray, np.ndarray]

Example:

>>> # if the prim is in position (1.0, 0.5, 0.0) with respect to the world frame
>>> position, orientation = prim.get_local_pose()
>>> position
[0. 0. 0.]
>>> orientation
[0. 0. 0.]
get_local_scale() numpy.ndarray

Get prim’s scale with respect to the local frame (the parent’s frame)

Returns

scale applied to the prim’s dimensions in the local frame. shape is (3, ).

Return type

np.ndarray

Example:

>>> prim.get_local_scale()
[1. 1. 1.]
get_mass() float

Get the mass of the rigid body

Returns

mass of the rigid body in kg.

Return type

float

Example:

>>> prim.get_mass()
0
get_min_torsional_patch_radius() float

Get the minimum radius of the contact patch used to apply torsional friction

Search for “Torsional Patch Radius” in PhysX docs for more details

Returns

minimum radius of the contact patch used to apply torsional friction. Allowed range [0, max_float].

Return type

float

Example:

>>> prim.get_min_torsional_patch_radius()
0.0
get_net_contact_forces(dt: float = 1.0) Union[numpy.ndarray, torch.Tensor]

If contact forces of the prims in the view are tracked, this method returns the net contact forces on prims. i.e., a matrix of dimension (1, 3)

Parameters

dt (float) – time step multiplier to convert the underlying impulses to forces. If the default value is used then the forces are in fact contact impulses

Returns

Net contact forces of the prims with shape (3).

Return type

Union[np.ndarray, torch.Tensor]

get_radius() float

Get the sphere radius

Returns

sphere radius

Return type

float

Example:

>>> prim.get_radius()
1.0
get_rest_offset() float

Get the rest offset

Two shapes will come to rest at a distance equal to the sum of their rest offset values. If the rest offset is 0, they should converge to touching exactly

Search for Advanced Collision Detection in PhysX docs for more details

Returns

rest offset of the collision shape.

Return type

float

Example:

>>> prim.get_rest_offset()
-inf
get_sleep_threshold() float

Get the threshold for the rigid body to enter a sleep state

Search for Rigid Body Dynamics > Sleeping in PhysX docs for more details

Returns

Mass-normalized kinetic energy threshold below which

an actor may go to sleep. Range: [0, inf) Defaults: 0.00005 * tolerancesSpeed* tolerancesSpeed Units: distance^2 / second^2.

Return type

float

Example:

>>> prim.get_sleep_threshold()
5e-05
get_torsional_patch_radius() float

Get the radius of the contact patch used to apply torsional friction

Search for “Torsional Patch Radius” in PhysX docs for more details

Returns

radius of the contact patch used to apply torsional friction. Allowed range [0, max_float].

Return type

float

Example:

>>> prim.get_torsional_patch_radius()
0.0
get_visibility() bool
Returns

true if the prim is visible in stage. false otherwise.

Return type

bool

Example:

>>> # get the visible state of an visible prim on the stage
>>> prim.get_visibility()
True
get_world_pose() Tuple[numpy.ndarray, numpy.ndarray]

Get prim’s pose with respect to the world’s frame

Returns

first index is the position in the world frame (with shape (3, )). Second index is quaternion orientation (with shape (4, )) in the world frame

Return type

Tuple[np.ndarray, np.ndarray]

Example:

>>> # if the prim is in position (1.0, 0.5, 0.0) with respect to the world frame
>>> position, orientation = prim.get_world_pose()
>>> position
[1.  0.5 0. ]
>>> orientation
[1. 0. 0. 0.]
get_world_scale() numpy.ndarray

Get prim’s scale with respect to the world’s frame

Returns

scale applied to the prim’s dimensions in the world frame. shape is (3, ).

Return type

np.ndarray

Example:

>>> prim.get_world_scale()
[1. 1. 1.]
initialize(physics_sim_view=None) None

Create a physics simulation view if not passed and using PhysX tensor API

Note

If the prim has been added to the world scene (e.g., world.scene.add(prim)), it will be automatically initialized when the world is reset (e.g., world.reset()).

Parameters

physics_sim_view (omni.physics.tensors.SimulationView, optional) – current physics simulation view. Defaults to None.

Example:

>>> prim.initialize()
is_valid() bool

Check if the prim path has a valid USD Prim at it

Returns

True is the current prim path corresponds to a valid prim in stage. False otherwise.

Return type

bool

Example:

>>> # given an existing and valid prim
>>> prims.is_valid()
True
is_visual_material_applied() bool

Check if there is a visual material applied

Returns

True if there is a visual material applied. False otherwise.

Return type

bool

Example:

>>> # given a visual material applied
>>> prim.is_visual_material_applied()
True
property name: Optional[str]

Returns: str: name given to the prim when instantiating it. Otherwise None.

Used to query if the prim is a non root articulation link

Returns

True if the prim itself is a non root link

Return type

bool

Example:

>>> # for a wrapped articulation (where the root prim has the Physics Articulation Root property applied)
>>> prim.non_root_articulation_link
False
post_reset() None

Reset the prim to its default state (position and orientation).

Note

For an articulation, in addition to configuring the root prim’s default position and spatial orientation (defined via the set_default_state method), the joint’s positions, velocities, and efforts (defined via the set_joints_default_state method) are imposed

Example:

>>> prim.post_reset()
property prim: pxr.Usd.Prim

Returns: Usd.Prim: USD Prim object that this object holds.

property prim_path: str

Returns: str: prim path in the stage

set_angular_velocity(velocity: numpy.ndarray) None

Set the angular velocity of the rigid body in stage

Warning

This method will immediately set the articulation state

Parameters

velocity (np.ndarray) – angular velocity to set the rigid prim to. Shape (3,).

Hint

This method belongs to the methods used to set the rigid prim kinematic state:

set_linear_velocity, set_angular_velocity

Example:

>>> prim.set_angular_velocity(np.array([0.0, 0.0, 10.0]))
set_collision_approximation(approximation_type: str) None

Set the collision approximation

Approximation

Full name

Description

"none"

Triangle Mesh

The mesh geometry is used directly as a collider without any approximation

"convexDecomposition"

Convex Decomposition

A convex mesh decomposition is performed. This results in a set of convex mesh colliders

"convexHull"

Convex Hull

A convex hull of the mesh is generated and used as the collider

"boundingSphere"

Bounding Sphere

A bounding sphere is computed around the mesh and used as a collider

"boundingCube"

Bounding Cube

An optimally fitting box collider is computed around the mesh

"meshSimplification"

Mesh Simplification

A mesh simplification step is performed, resulting in a simplified triangle mesh collider

"sdf"

SDF Mesh

SDF (Signed-Distance-Field) use high-detail triangle meshes as collision shape

"sphereFill"

Sphere Approximation

A sphere mesh decomposition is performed. This results in a set of sphere colliders

Note

Use Convex Decomposition or SDF (Signed-Distance-Field) tri-meshes to capture details better

Warning

Switching to Convex Decomposition or SDF (Signed-Distance-Field) will have a simulation performance impact due to higher computational cost

Parameters

approximation_type (str) – approximation used for collision

Example:

>>> prim.set_collision_approximation("convexDecomposition")
set_collision_enabled(enabled: bool) None

Enable/disable the Collision API

Parameters

enabled (bool) – Whether to enable or disable the Collision API

Example:

>>> # disable collisions
>>> prim.set_collision_enabled(False)
set_contact_offset(offset: float) None

Set the contact offset

Shapes whose distance is less than the sum of their contact offset values will generate contacts

Search for Advanced Collision Detection in PhysX docs for more details

Warning

The contact offset must be positive and greater than the rest offset

Parameters

offset (float) – Contact offset of a collision shape. Allowed range [maximum(0, rest_offset), 0]. Default value is -inf, means default is picked by simulation based on the shape extent.

Example:

>>> prim.set_contact_offset(0.02)
set_default_state(position: Optional[Sequence[float]] = None, orientation: Optional[Sequence[float]] = None, linear_velocity: Optional[numpy.ndarray] = None, angular_velocity: Optional[numpy.ndarray] = None) None

Set the default state of the prim (position, orientation and linear and angular velocities), that will be used after each reset

Note

The default states will be set during post-reset (e.g., calling .post_reset() or world.reset() methods)

Parameters
  • position (Optional[Sequence[float]], optional) – position in the world frame of the prim. shape is (3, ). Defaults to None, which means left unchanged.

  • orientation (Optional[Sequence[float]], optional) – quaternion orientation in the world frame of the prim. quaternion is scalar-first (w, x, y, z). shape is (4, ). Defaults to None, which means left unchanged.

  • linear_velocity (np.ndarray) – linear velocity to set the rigid prim to. Shape (3,).

  • angular_velocity (np.ndarray) – angular velocity to set the rigid prim to. Shape (3,).

Example:

>>> prim.set_default_state(
...     position=np.array([1.0, 2.0, 3.0]),
...     orientation=np.array([1.0, 0.0, 0.0, 0.0]),
...     linear_velocity=np.array([0.0, 0.0, 0.0]),
...     angular_velocity=np.array([0.0, 0.0, 0.0])
... )
>>>
>>> prim.post_reset()
set_density(density: float) None

Set the density of the rigid body

Parameters

mass (float) – density of the rigid body.

Example:

>>> prim.set_density(0.9)
set_linear_velocity(velocity: numpy.ndarray)

Set the linear velocity of the rigid body in stage

Warning

This method will immediately set the rigid prim state

Parameters

velocity (np.ndarray) – linear velocity to set the rigid prim to. Shape (3,).

Hint

This method belongs to the methods used to set the rigid prim kinematic state:

set_linear_velocity, set_angular_velocity

Example:

>>> prim.set_linear_velocity(np.array([5.0, 0.0, 0.0]))
set_local_pose(translation: Optional[Sequence[float]] = None, orientation: Optional[Sequence[float]] = None) None

Set prim’s pose with respect to the local frame (the prim’s parent frame).

Warning

This method will change (teleport) the prim pose immediately to the indicated value

Parameters
  • translation (Optional[Sequence[float]], optional) – translation in the local frame of the prim (with respect to its parent prim). shape is (3, ). Defaults to None, which means left unchanged.

  • orientation (Optional[Sequence[float]], optional) – quaternion orientation in the local frame of the prim. quaternion is scalar-first (w, x, y, z). shape is (4, ). Defaults to None, which means left unchanged.

Hint

This method belongs to the methods used to set the prim state

Example:

>>> prim.set_local_pose(translation=np.array([1.0, 0.5, 0.0]), orientation=np.array([1., 0., 0., 0.]))
set_local_scale(scale: Optional[Sequence[float]]) None

Set prim’s scale with respect to the local frame (the prim’s parent frame).

Parameters

scale (Optional[Sequence[float]]) – scale to be applied to the prim’s dimensions. shape is (3, ). Defaults to None, which means left unchanged.

Example:

>>> # scale prim 10 times smaller
>>> prim.set_local_scale(np.array([0.1, 0.1, 0.1]))
set_mass(mass: float) None

Set the mass of the rigid body

Parameters

mass (float) – mass of the rigid body in kg.

Example:

>>> prim.set_mass(1.0)
set_min_torsional_patch_radius(radius: float) None

Set the minimum radius of the contact patch used to apply torsional friction

Search for “Torsional Patch Radius” in PhysX docs for more details

Parameters

radius (float) – minimum radius of the contact patch used to apply torsional friction. Allowed range [0, max_float].

Example:

>>> prim.set_min_torsional_patch_radius(0.05)
set_radius(radius: float) None

Set the sphere radius

Parameters

radius (float) – sphere radius

Example:

>>> prim.set_radius(2.0)
set_rest_offset(offset: float) None

Set the rest offset

Two shapes will come to rest at a distance equal to the sum of their rest offset values. If the rest offset is 0, they should converge to touching exactly

Search for Advanced Collision Detection in PhysX docs for more details

Warning

The contact offset must be positive and greater than the rest offset

Parameters

offset (float) – Rest offset of a collision shape. Allowed range [-max_float, contact_offset. Default value is -inf, means default is picked by simulation. For rigid bodies its zero.

Example:

>>> prim.set_rest_offset(0.01)
set_sleep_threshold(threshold: float) None

Set the threshold for the rigid body to enter a sleep state

Search for Rigid Body Dynamics > Sleeping in PhysX docs for more details

Parameters

threshold (float) – Mass-normalized kinetic energy threshold below which an actor may go to sleep. Range: [0, inf) Defaults: 0.00005 * tolerancesSpeed* tolerancesSpeed Units: distance^2 / second^2.

Example:

>>> prim.set_sleep_threshold(1e-5)
set_torsional_patch_radius(radius: float) None

Set the radius of the contact patch used to apply torsional friction

Search for “Torsional Patch Radius” in PhysX docs for more details

Parameters

radius (float) – radius of the contact patch used to apply torsional friction. Allowed range [0, max_float].

Example:

>>> prim.set_torsional_patch_radius(0.1)
set_visibility(visible: bool) None

Set the visibility of the prim in stage

Parameters

visible (bool) – flag to set the visibility of the usd prim in stage.

Example:

>>> # make prim not visible in the stage
>>> prim.set_visibility(visible=False)
set_world_pose(position: Optional[Sequence[float]] = None, orientation: Optional[Sequence[float]] = None) None

Ses prim’s pose with respect to the world’s frame

Warning

This method will change (teleport) the prim pose immediately to the indicated value

Parameters
  • position (Optional[Sequence[float]], optional) – position in the world frame of the prim. shape is (3, ). Defaults to None, which means left unchanged.

  • orientation (Optional[Sequence[float]], optional) – quaternion orientation in the world frame of the prim. quaternion is scalar-first (w, x, y, z). shape is (4, ). Defaults to None, which means left unchanged.

Hint

This method belongs to the methods used to set the prim state

Example:

>>> prim.set_world_pose(position=np.array([1.0, 0.5, 0.0]), orientation=np.array([1., 0., 0., 0.]))

Physics Context

class PhysicsContext(physics_dt: Optional[float] = None, prim_path: str = '/physicsScene', sim_params: Optional[dict] = None, set_defaults: bool = True, backend: str = 'numpy', device: Optional[str] = None)
Provides high level functions to deal with a physics scene and its settings. This will create a

a PhysicsScene prim at the specified prim path in case there is no PhysicsScene present in the current stage. If there is a PhysicsScene present, it will discard the prim_path specified and sets the default settings on the current PhysicsScene found.

Parameters
  • physics_dt (float, optional) – specifies the physics_dt of the simulation. Defaults to 1.0 / 60.0.

  • prim_path (Optional[str], optional) – specifies the prim path to create a PhysicsScene at, only in the case where no PhysicsScene already defined. Defaults to “/physicsScene”.

  • set_defaults (bool, optional) – set to True to use the defaults physics parameters [physics_dt = 1.0/ 60.0, gravity = -9.81 m / s ccd_enabled, stabilization_enabled, gpu dynamics turned off, broadcast type is MBP, solver type is TGS]. Defaults to True.

  • backend (str, optional) – specifies the backend to be used (numpy or torch). Defaults to numpy.

  • device (Optional[str], optional) – specifies the device to be used if running on the gpu with torch backend.

Raises
  • Exception – If prim_path is not absolute.

  • Exception – if prim_path already exists and its type is not a PhysicsScene.

property device: str
enable_ccd(flag: bool) None
Enables a second broad phase after integration that makes it possible to prevent objects from tunneling

through each other.

Parameters

flag (bool) – enables or disables ccd on the PhysicsScene

Raises

Exception – If the prim path registered in context doesn’t correspond to a valid prim path currently.

enable_fabric(enable)
enable_gpu_dynamics(flag: bool) None

Enables gpu dynamics pipeline, required for deformables for instance.

Parameters

flag (bool) – enables or disables gpu dynamics on the PhysicsScene

Raises

Exception – If the prim path registered in context doesn’t correspond to a valid prim path currently.

enable_stablization(flag: bool) None

Enables additional stabilization pass in the solver.

Parameters

flag (bool) – enables or disables stabilization on the PhysicsScene

Raises

Exception – If the prim path registered in context doesn’t correspond to a valid prim path currently.

get_bounce_threshold() float

[summary]

Raises

Exception – [description]

Returns

[description]

Return type

float

get_broadphase_type() str

Gets current broadcast phase algorithm type.

Raises

Exception – If the prim path registered in context doesn’t correspond to a valid prim path currently.

Returns

Broadcast phase algorithm used.

Return type

str

get_current_physics_scene_prim() Optional[pxr.Usd.Prim]

Used to return the PhysicsScene prim in stage by traversing the stage.

Returns

returns a PhysicsScene prim if found in current stage. Otherwise, None.

Return type

Optional[Usd.Prim]

get_enable_scene_query_support() bool

Retrieves the Enable Scene Query Support attribute in Physx Scene

Raises

Exception – [description]

Returns

enable scene query support attribute

Return type

bool

get_friction_correlation_distance() float

[summary]

Raises

Exception – [description]

Returns

[description]

Return type

float

get_friction_offset_threshold() float

[summary]

Raises

Exception – [description]

Returns

[description]

Return type

float

get_gpu_collision_stack_size() int

[summary]

Raises

Exception – [description]

Returns

[description]

Return type

int

get_gpu_found_lost_aggregate_pairs_capacity() int

[summary]

Raises

Exception – [description]

Returns

[description]

Return type

int

get_gpu_found_lost_pairs_capacity() int

[summary]

Raises

Exception – [description]

Returns

[description]

Return type

int

get_gpu_heap_capacity() int

[summary]

Raises

Exception – [description]

Returns

[description]

Return type

int

get_gpu_max_num_partitions() int

[summary]

Raises

Exception – [description]

Returns

[description]

Return type

int

get_gpu_max_particle_contacts() int

[summary]

Raises

Exception – [description]

Returns

[description]

Return type

int

get_gpu_max_rigid_contact_count() int

[summary]

Raises

Exception – [description]

Returns

[description]

Return type

int

get_gpu_max_rigid_patch_count() int

[summary]

Raises

Exception – [description]

Returns

[description]

Return type

int

get_gpu_max_soft_body_contacts() int

[summary]

Raises

Exception – [description]

Returns

[description]

Return type

int

get_gpu_temp_buffer_capacity() int

[summary]

Raises

Exception – [description]

Returns

[description]

Return type

int

get_gpu_total_aggregate_pairs_capacity() int

[summary]

Raises

Exception – [description]

Returns

[description]

Return type

int

get_gravity() Tuple[List, float]

Gets current gravity.

Raises

Exception – If the prim path registered in context doesn’t correspond to a valid prim path currently.

Returns

returns a tuple, first element corresponds to the gravity direction vector and second element is the magnitude.

Return type

Tuple[list, float]

get_invert_collision_group_filter() int

[summary]

Raises

Exception – [description]

Returns

[description]

Return type

int

get_physics_dt() float

Returns the current physics dt.

Raises

Exception – If the prim path registered in context doesn’t correspond to a valid prim path currently.

Returns

physics dt.

Return type

float

get_physx_update_transformations_settings() Tuple[bool, bool, bool, bool]

Gets how physx syncs with the usd when transformations are updated.

Returns

[update_to_fast_cache, update_to_usd, update_velocities_to_usd, output_velocities_local_space]

Return type

Tuple[bool, bool, bool, bool]

get_solver_type() str

Gets current solver type.

Raises

Exception – If the prim path registered in context doesn’t correspond to a valid prim path currently.

Returns

solver used for simulation.

Return type

str

is_ccd_enabled() bool

Checks if ccd is enabled.

Raises

Exception – If the prim path registered in context doesn’t correspond to a valid prim path currently.

Returns

True if ccd is enabled, otherwise False.

Return type

bool

is_gpu_dynamics_enabled() bool

Checks if Gpu Dynamics is enabled.

Raises

Exception – If the prim path registered in context doesn’t correspond to a valid prim path currently.

Returns

True if Gpu Dynamics is enabled, otherwise False.

Return type

bool

is_stablization_enabled() bool

Checks if stabilization is enabled.

Raises

Exception – If the prim path registered in context doesn’t correspond to a valid prim path currently.

Returns

True if stabilization is enabled, otherwise False.

Return type

bool

property prim_path
set_bounce_threshold(value: float) None

[summary]

Parameters

value (float) – [description]

Raises

Exception – [description]

set_broadphase_type(broadcast_type: str) None

Broadcast phase algorithm used in simulation.

Parameters

broadcast_type (str) – type of broadcasting to be used, can be “MBP”

Raises

Exception – If the prim path registered in context doesn’t correspond to a valid prim path currently.

set_enable_scene_query_support(enable_scene_query_support: bool) None

Sets the Enable Scene Query Support attribute in Physx Scene

Parameters

enable_scene_query_support (bool) – Whether to enable scene query support

Raises

Exception – [description]

set_friction_correlation_distance(value: float) None

[summary]

Parameters

value (float) – [description]

Raises

Exception – [description]

set_friction_offset_threshold(value: float) None

[summary]

Parameters

value (float) – [description]

Raises

Exception – [description]

set_gpu_collision_stack_size(value: int) None

[summary]

Parameters

value (int) – [description]

Raises

Exception – [description]

set_gpu_found_lost_aggregate_pairs_capacity(value: int) None

[summary]

Parameters

value (int) – [description]

Raises

Exception – [description]

set_gpu_found_lost_pairs_capacity(value: int) None

[summary]

Parameters

value (int) – [description]

Raises

Exception – [description]

set_gpu_heap_capacity(value: int) None

[summary]

Parameters

value (int) – [description]

Raises

Exception – [description]

set_gpu_max_num_partitions(value: int) None

[summary]

Parameters

value (int) – [description]

Raises

Exception – [description]

set_gpu_max_particle_contacts(value: int) None

[summary]

Parameters

value (int) – [description]

Raises

Exception – [description]

set_gpu_max_rigid_contact_count(value: int) None

[summary]

Parameters

value (int) – [description]

Raises

Exception – [description]

set_gpu_max_rigid_patch_count(value: int) None

[summary]

Parameters

value (int) – [description]

Raises

Exception – [description]

set_gpu_max_soft_body_contacts(value: int) None

[summary]

Parameters

value (int) – [description]

Raises

Exception – [description]

set_gpu_temp_buffer_capacity(value: int) None

[summary]

Parameters

value (int) – [description]

Raises

Exception – [description]

set_gpu_total_aggregate_pairs_capacity(value: int) None

[summary]

Parameters

value (int) – [description]

Raises

Exception – [description]

set_gravity(value: float) None

sets the gravity direction and magnitude.

Parameters

value (float) – gravity value to be used in simulation.

Raises

Exception – If the prim path registered in context doesn’t correspond to a valid prim path currently.

set_invert_collision_group_filter(invert_collision_group_filter: bool) None

[summary]

Parameters

invert_collision_group_filter (bool) – [description]

Raises

Exception – [description]

set_physics_dt(dt: float = 0.016666666666666666, substeps: int = 1) None

Sets the physics dt on the PhysicsScene

Parameters
  • dt (float, optional) – physics dt. Defaults to 1.0/60.0.

  • substeps (int, optional) – number of physics steps to run for before rendering a frame. Defaults to 1.

Raises
  • Exception – If the prim path registered in context doesn’t correspond to a valid prim path currently.

  • ValueError – Physics dt must be a >= 0.

  • ValueError – Physics dt must be a <= 1.0.

set_physx_update_transformations_settings(update_to_fast_cache: Optional[bool] = None, update_to_usd: Optional[bool] = None, update_velocities_to_usd: Optional[bool] = None, output_velocities_local_space: Optional[bool] = None) None

Sets how physx syncs with the usd when transformations are updated.

Parameters
  • update_to_fast_cache (bool, optional) – Uses Fast cache if set to True. Defaults to True.

  • update_to_usd (bool, optional) – Updates to USD the transformations. Defaults to True.

  • update_velocities_to_usd (bool, optional) – Updates Velocities to USD. Defaults to True.

  • output_velocities_local_space (bool, optional) – Output the velocities in the local frame and not the world frame. Defaults to False.

set_solver_type(solver_type: str) None

solver used for simulation.

Parameters

solver_type (str) – can be “TGS” or “PGS”. for references look at..

Raises

Exception – If the prim path registered in context doesn’t correspond to a valid prim path currently.

property use_fabric
property use_gpu_pipeline
property use_gpu_sim
warm_start()

Prims

Base Sensor

class BaseSensor(prim_path: str, name: str = 'base_sensor', position: Optional[Sequence[float]] = None, translation: Optional[Sequence[float]] = None, orientation: Optional[Sequence[float]] = None, scale: Optional[Sequence[float]] = None, visible: Optional[bool] = None)

Provides a common properties and methods to deal with prims as a sensor

Note

This class, which inherits from XFormPrim, does not currently add any new property/method to it. Its definition is oriented to future implementations.

Parameters
  • prim_path (str) – prim path of the Prim to encapsulate or create.

  • name (str, optional) – shortname to be used as a key by Scene class. Note: needs to be unique if the object is added to the Scene. Defaults to “base_sensor”.

  • position (Optional[Sequence[float]], optional) – position in the world frame of the prim. shape is (3, ). Defaults to None, which means left unchanged.

  • translation (Optional[Sequence[float]], optional) – translation in the local frame of the prim (with respect to its parent prim). shape is (3, ). Defaults to None, which means left unchanged.

  • orientation (Optional[Sequence[float]], optional) – quaternion orientation in the world/ local frame of the prim (depends if translation or position is specified). quaternion is scalar-first (w, x, y, z). shape is (4, ). Defaults to None, which means left unchanged.

  • scale (Optional[Sequence[float]], optional) – local scale to be applied to the prim’s dimensions. shape is (3, ). Defaults to None, which means left unchanged.

  • visible (bool, optional) – set to false for an invisible prim in the stage while rendering. Defaults to True.

Raises

Exception – if translation and position defined at the same time

apply_visual_material(visual_material: omni.isaac.core.materials.visual_material.VisualMaterial, weaker_than_descendants: bool = False) None

Apply visual material to the held prim and optionally its descendants.

Parameters
  • visual_material (VisualMaterial) – visual material to be applied to the held prim. Currently supports PreviewSurface, OmniPBR and OmniGlass.

  • weaker_than_descendants (bool, optional) – True if the material shouldn’t override the descendants materials, otherwise False. Defaults to False.

Example:

>>> from omni.isaac.core.materials import OmniGlass
>>>
>>> # create a dark-red glass visual material
>>> material = OmniGlass(
...     prim_path="/World/material/glass",  # path to the material prim to create
...     ior=1.25,
...     depth=0.001,
...     thin_walled=False,
...     color=np.array([0.5, 0.0, 0.0])
... )
>>> prim.apply_visual_material(material)
get_applied_visual_material() omni.isaac.core.materials.visual_material.VisualMaterial

Return the current applied visual material in case it was applied using apply_visual_material or it’s one of the following materials that was already applied before: PreviewSurface, OmniPBR and OmniGlass.

Returns

the current applied visual material if its type is currently supported.

Return type

VisualMaterial

Example:

>>> # given a visual material applied
>>> prim.get_applied_visual_material()
<omni.isaac.core.materials.omni_glass.OmniGlass object at 0x7f36263106a0>
get_default_state() omni.isaac.core.utils.types.XFormPrimState

Get the default prim states (spatial position and orientation).

Returns

an object that contains the default state of the prim (position and orientation)

Return type

XFormPrimState

Example:

>>> state = prim.get_default_state()
>>> state
<omni.isaac.core.utils.types.XFormPrimState object at 0x7f33addda650>
>>>
>>> state.position
[-4.5299529e-08 -1.8347054e-09 -2.8610229e-08]
>>> state.orientation
[1. 0. 0. 0.]
get_local_pose() Tuple[numpy.ndarray, numpy.ndarray]

Get prim’s pose with respect to the local frame (the prim’s parent frame)

Returns

first index is the position in the local frame (with shape (3, )). Second index is quaternion orientation (with shape (4, )) in the local frame

Return type

Tuple[np.ndarray, np.ndarray]

Example:

>>> # if the prim is in position (1.0, 0.5, 0.0) with respect to the world frame
>>> position, orientation = prim.get_local_pose()
>>> position
[0. 0. 0.]
>>> orientation
[0. 0. 0.]
get_local_scale() numpy.ndarray

Get prim’s scale with respect to the local frame (the parent’s frame)

Returns

scale applied to the prim’s dimensions in the local frame. shape is (3, ).

Return type

np.ndarray

Example:

>>> prim.get_local_scale()
[1. 1. 1.]
get_visibility() bool
Returns

true if the prim is visible in stage. false otherwise.

Return type

bool

Example:

>>> # get the visible state of an visible prim on the stage
>>> prim.get_visibility()
True
get_world_pose() Tuple[numpy.ndarray, numpy.ndarray]

Get prim’s pose with respect to the world’s frame

Returns

first index is the position in the world frame (with shape (3, )). Second index is quaternion orientation (with shape (4, )) in the world frame

Return type

Tuple[np.ndarray, np.ndarray]

Example:

>>> # if the prim is in position (1.0, 0.5, 0.0) with respect to the world frame
>>> position, orientation = prim.get_world_pose()
>>> position
[1.  0.5 0. ]
>>> orientation
[1. 0. 0. 0.]
get_world_scale() numpy.ndarray

Get prim’s scale with respect to the world’s frame

Returns

scale applied to the prim’s dimensions in the world frame. shape is (3, ).

Return type

np.ndarray

Example:

>>> prim.get_world_scale()
[1. 1. 1.]
initialize(physics_sim_view=None) None

Create a physics simulation view if not passed and using PhysX tensor API

Note

If the prim has been added to the world scene (e.g., world.scene.add(prim)), it will be automatically initialized when the world is reset (e.g., world.reset()).

Parameters

physics_sim_view (omni.physics.tensors.SimulationView, optional) – current physics simulation view. Defaults to None.

Example:

>>> prim.initialize()
is_valid() bool

Check if the prim path has a valid USD Prim at it

Returns

True is the current prim path corresponds to a valid prim in stage. False otherwise.

Return type

bool

Example:

>>> # given an existing and valid prim
>>> prims.is_valid()
True
is_visual_material_applied() bool

Check if there is a visual material applied

Returns

True if there is a visual material applied. False otherwise.

Return type

bool

Example:

>>> # given a visual material applied
>>> prim.is_visual_material_applied()
True
property name: Optional[str]

Returns: str: name given to the prim when instantiating it. Otherwise None.

Used to query if the prim is a non root articulation link

Returns

True if the prim itself is a non root link

Return type

bool

Example:

>>> # for a wrapped articulation (where the root prim has the Physics Articulation Root property applied)
>>> prim.non_root_articulation_link
False
post_reset() None

Reset the prim to its default state (position and orientation).

Note

For an articulation, in addition to configuring the root prim’s default position and spatial orientation (defined via the set_default_state method), the joint’s positions, velocities, and efforts (defined via the set_joints_default_state method) are imposed

Example:

>>> prim.post_reset()
property prim: pxr.Usd.Prim

Returns: Usd.Prim: USD Prim object that this object holds.

property prim_path: str

Returns: str: prim path in the stage

set_default_state(position: Optional[Sequence[float]] = None, orientation: Optional[Sequence[float]] = None) None

Set the default state of the prim (position and orientation), that will be used after each reset.

Parameters
  • position (Optional[Sequence[float]], optional) – position in the world frame of the prim. shape is (3, ). Defaults to None, which means left unchanged.

  • orientation (Optional[Sequence[float]], optional) – quaternion orientation in the world frame of the prim. quaternion is scalar-first (w, x, y, z). shape is (4, ). Defaults to None, which means left unchanged.

Example:

>>> # configure default state
>>> prim.set_default_state(position=np.array([1.0, 0.5, 0.0]), orientation=np.array([1, 0, 0, 0]))
>>>
>>> # set default states during post-reset
>>> prim.post_reset()
set_local_pose(translation: Optional[Sequence[float]] = None, orientation: Optional[Sequence[float]] = None) None

Set prim’s pose with respect to the local frame (the prim’s parent frame).

Warning

This method will change (teleport) the prim pose immediately to the indicated value

Parameters
  • translation (Optional[Sequence[float]], optional) – translation in the local frame of the prim (with respect to its parent prim). shape is (3, ). Defaults to None, which means left unchanged.

  • orientation (Optional[Sequence[float]], optional) – quaternion orientation in the local frame of the prim. quaternion is scalar-first (w, x, y, z). shape is (4, ). Defaults to None, which means left unchanged.

Hint

This method belongs to the methods used to set the prim state

Example:

>>> prim.set_local_pose(translation=np.array([1.0, 0.5, 0.0]), orientation=np.array([1., 0., 0., 0.]))
set_local_scale(scale: Optional[Sequence[float]]) None

Set prim’s scale with respect to the local frame (the prim’s parent frame).

Parameters

scale (Optional[Sequence[float]]) – scale to be applied to the prim’s dimensions. shape is (3, ). Defaults to None, which means left unchanged.

Example:

>>> # scale prim 10 times smaller
>>> prim.set_local_scale(np.array([0.1, 0.1, 0.1]))
set_visibility(visible: bool) None

Set the visibility of the prim in stage

Parameters

visible (bool) – flag to set the visibility of the usd prim in stage.

Example:

>>> # make prim not visible in the stage
>>> prim.set_visibility(visible=False)
set_world_pose(position: Optional[Sequence[float]] = None, orientation: Optional[Sequence[float]] = None) None

Ses prim’s pose with respect to the world’s frame

Warning

This method will change (teleport) the prim pose immediately to the indicated value

Parameters
  • position (Optional[Sequence[float]], optional) – position in the world frame of the prim. shape is (3, ). Defaults to None, which means left unchanged.

  • orientation (Optional[Sequence[float]], optional) – quaternion orientation in the world frame of the prim. quaternion is scalar-first (w, x, y, z). shape is (4, ). Defaults to None, which means left unchanged.

Hint

This method belongs to the methods used to set the prim state

Example:

>>> prim.set_world_pose(position=np.array([1.0, 0.5, 0.0]), orientation=np.array([1., 0., 0., 0.]))

XForm Prim

class XFormPrim(prim_path: str, name: str = 'xform_prim', position: Optional[Sequence[float]] = None, translation: Optional[Sequence[float]] = None, orientation: Optional[Sequence[float]] = None, scale: Optional[Sequence[float]] = None, visible: Optional[bool] = None)

Provides high level functions to deal with an Xform prim (only one Xform prim) and its attributes/properties

If there is an Xform prim present at the path, it will use it. Otherwise, a new XForm prim at the specified prim path will be created

Note

The prim will have xformOp:orient, xformOp:translate and xformOp:scale only post-init, unless it is a non-root articulation link.

Parameters
  • prim_path (str) – prim path of the Prim to encapsulate or create.

  • name (str, optional) – shortname to be used as a key by Scene class. Note: needs to be unique if the object is added to the Scene. Defaults to “xform_prim”.

  • position (Optional[Sequence[float]], optional) – position in the world frame of the prim. shape is (3, ). Defaults to None, which means left unchanged.

  • translation (Optional[Sequence[float]], optional) – translation in the local frame of the prim (with respect to its parent prim). shape is (3, ). Defaults to None, which means left unchanged.

  • orientation (Optional[Sequence[float]], optional) – quaternion orientation in the world/ local frame of the prim (depends if translation or position is specified). quaternion is scalar-first (w, x, y, z). shape is (4, ). Defaults to None, which means left unchanged.

  • scale (Optional[Sequence[float]], optional) – local scale to be applied to the prim’s dimensions. shape is (3, ). Defaults to None, which means left unchanged.

  • visible (bool, optional) – set to false for an invisible prim in the stage while rendering. Defaults to True.

Raises

Exception – if translation and position defined at the same time

Example:

>>> from omni.isaac.core.prims import XFormPrim
>>>
>>> # given the stage: /World. Get the Xform prim at /World
>>> prim = XFormPrim("/World")
>>> prim
<omni.isaac.core.prims.xform_prim.XFormPrim object at 0x7f52381547c0>
>>>
>>> # create a new Xform prim at path: /World/Objects
>>> prim = XFormPrim("/World/Objects", name="objects")
>>> prim
<omni.isaac.core.prims.xform_prim.XFormPrim object at 0x7f525c11d420>
apply_visual_material(visual_material: omni.isaac.core.materials.visual_material.VisualMaterial, weaker_than_descendants: bool = False) None

Apply visual material to the held prim and optionally its descendants.

Parameters
  • visual_material (VisualMaterial) – visual material to be applied to the held prim. Currently supports PreviewSurface, OmniPBR and OmniGlass.

  • weaker_than_descendants (bool, optional) – True if the material shouldn’t override the descendants materials, otherwise False. Defaults to False.

Example:

>>> from omni.isaac.core.materials import OmniGlass
>>>
>>> # create a dark-red glass visual material
>>> material = OmniGlass(
...     prim_path="/World/material/glass",  # path to the material prim to create
...     ior=1.25,
...     depth=0.001,
...     thin_walled=False,
...     color=np.array([0.5, 0.0, 0.0])
... )
>>> prim.apply_visual_material(material)
get_applied_visual_material() omni.isaac.core.materials.visual_material.VisualMaterial

Return the current applied visual material in case it was applied using apply_visual_material or it’s one of the following materials that was already applied before: PreviewSurface, OmniPBR and OmniGlass.

Returns

the current applied visual material if its type is currently supported.

Return type

VisualMaterial

Example:

>>> # given a visual material applied
>>> prim.get_applied_visual_material()
<omni.isaac.core.materials.omni_glass.OmniGlass object at 0x7f36263106a0>
get_default_state() omni.isaac.core.utils.types.XFormPrimState

Get the default prim states (spatial position and orientation).

Returns

an object that contains the default state of the prim (position and orientation)

Return type

XFormPrimState

Example:

>>> state = prim.get_default_state()
>>> state
<omni.isaac.core.utils.types.XFormPrimState object at 0x7f33addda650>
>>>
>>> state.position
[-4.5299529e-08 -1.8347054e-09 -2.8610229e-08]
>>> state.orientation
[1. 0. 0. 0.]
get_local_pose() Tuple[numpy.ndarray, numpy.ndarray]

Get prim’s pose with respect to the local frame (the prim’s parent frame)

Returns

first index is the position in the local frame (with shape (3, )). Second index is quaternion orientation (with shape (4, )) in the local frame

Return type

Tuple[np.ndarray, np.ndarray]

Example:

>>> # if the prim is in position (1.0, 0.5, 0.0) with respect to the world frame
>>> position, orientation = prim.get_local_pose()
>>> position
[0. 0. 0.]
>>> orientation
[0. 0. 0.]
get_local_scale() numpy.ndarray

Get prim’s scale with respect to the local frame (the parent’s frame)

Returns

scale applied to the prim’s dimensions in the local frame. shape is (3, ).

Return type

np.ndarray

Example:

>>> prim.get_local_scale()
[1. 1. 1.]
get_visibility() bool
Returns

true if the prim is visible in stage. false otherwise.

Return type

bool

Example:

>>> # get the visible state of an visible prim on the stage
>>> prim.get_visibility()
True
get_world_pose() Tuple[numpy.ndarray, numpy.ndarray]

Get prim’s pose with respect to the world’s frame

Returns

first index is the position in the world frame (with shape (3, )). Second index is quaternion orientation (with shape (4, )) in the world frame

Return type

Tuple[np.ndarray, np.ndarray]

Example:

>>> # if the prim is in position (1.0, 0.5, 0.0) with respect to the world frame
>>> position, orientation = prim.get_world_pose()
>>> position
[1.  0.5 0. ]
>>> orientation
[1. 0. 0. 0.]
get_world_scale() numpy.ndarray

Get prim’s scale with respect to the world’s frame

Returns

scale applied to the prim’s dimensions in the world frame. shape is (3, ).

Return type

np.ndarray

Example:

>>> prim.get_world_scale()
[1. 1. 1.]
initialize(physics_sim_view=None) None

Create a physics simulation view if not passed and using PhysX tensor API

Note

If the prim has been added to the world scene (e.g., world.scene.add(prim)), it will be automatically initialized when the world is reset (e.g., world.reset()).

Parameters

physics_sim_view (omni.physics.tensors.SimulationView, optional) – current physics simulation view. Defaults to None.

Example:

>>> prim.initialize()
is_valid() bool

Check if the prim path has a valid USD Prim at it

Returns

True is the current prim path corresponds to a valid prim in stage. False otherwise.

Return type

bool

Example:

>>> # given an existing and valid prim
>>> prims.is_valid()
True
is_visual_material_applied() bool

Check if there is a visual material applied

Returns

True if there is a visual material applied. False otherwise.

Return type

bool

Example:

>>> # given a visual material applied
>>> prim.is_visual_material_applied()
True
property name: Optional[str]

Returns: str: name given to the prim when instantiating it. Otherwise None.

Used to query if the prim is a non root articulation link

Returns

True if the prim itself is a non root link

Return type

bool

Example:

>>> # for a wrapped articulation (where the root prim has the Physics Articulation Root property applied)
>>> prim.non_root_articulation_link
False
post_reset() None

Reset the prim to its default state (position and orientation).

Note

For an articulation, in addition to configuring the root prim’s default position and spatial orientation (defined via the set_default_state method), the joint’s positions, velocities, and efforts (defined via the set_joints_default_state method) are imposed

Example:

>>> prim.post_reset()
property prim: pxr.Usd.Prim

Returns: Usd.Prim: USD Prim object that this object holds.

property prim_path: str

Returns: str: prim path in the stage

set_default_state(position: Optional[Sequence[float]] = None, orientation: Optional[Sequence[float]] = None) None

Set the default state of the prim (position and orientation), that will be used after each reset.

Parameters
  • position (Optional[Sequence[float]], optional) – position in the world frame of the prim. shape is (3, ). Defaults to None, which means left unchanged.

  • orientation (Optional[Sequence[float]], optional) – quaternion orientation in the world frame of the prim. quaternion is scalar-first (w, x, y, z). shape is (4, ). Defaults to None, which means left unchanged.

Example:

>>> # configure default state
>>> prim.set_default_state(position=np.array([1.0, 0.5, 0.0]), orientation=np.array([1, 0, 0, 0]))
>>>
>>> # set default states during post-reset
>>> prim.post_reset()
set_local_pose(translation: Optional[Sequence[float]] = None, orientation: Optional[Sequence[float]] = None) None

Set prim’s pose with respect to the local frame (the prim’s parent frame).

Warning

This method will change (teleport) the prim pose immediately to the indicated value

Parameters
  • translation (Optional[Sequence[float]], optional) – translation in the local frame of the prim (with respect to its parent prim). shape is (3, ). Defaults to None, which means left unchanged.

  • orientation (Optional[Sequence[float]], optional) – quaternion orientation in the local frame of the prim. quaternion is scalar-first (w, x, y, z). shape is (4, ). Defaults to None, which means left unchanged.

Hint

This method belongs to the methods used to set the prim state

Example:

>>> prim.set_local_pose(translation=np.array([1.0, 0.5, 0.0]), orientation=np.array([1., 0., 0., 0.]))
set_local_scale(scale: Optional[Sequence[float]]) None

Set prim’s scale with respect to the local frame (the prim’s parent frame).

Parameters

scale (Optional[Sequence[float]]) – scale to be applied to the prim’s dimensions. shape is (3, ). Defaults to None, which means left unchanged.

Example:

>>> # scale prim 10 times smaller
>>> prim.set_local_scale(np.array([0.1, 0.1, 0.1]))
set_visibility(visible: bool) None

Set the visibility of the prim in stage

Parameters

visible (bool) – flag to set the visibility of the usd prim in stage.

Example:

>>> # make prim not visible in the stage
>>> prim.set_visibility(visible=False)
set_world_pose(position: Optional[Sequence[float]] = None, orientation: Optional[Sequence[float]] = None) None

Ses prim’s pose with respect to the world’s frame

Warning

This method will change (teleport) the prim pose immediately to the indicated value

Parameters
  • position (Optional[Sequence[float]], optional) – position in the world frame of the prim. shape is (3, ). Defaults to None, which means left unchanged.

  • orientation (Optional[Sequence[float]], optional) – quaternion orientation in the world frame of the prim. quaternion is scalar-first (w, x, y, z). shape is (4, ). Defaults to None, which means left unchanged.

Hint

This method belongs to the methods used to set the prim state

Example:

>>> prim.set_world_pose(position=np.array([1.0, 0.5, 0.0]), orientation=np.array([1., 0., 0., 0.]))

XForm Prim View

class XFormPrimView(prim_paths_expr: str, name: str = 'xform_prim_view', positions: Optional[Union[numpy.ndarray, torch.Tensor]] = None, translations: Optional[Union[numpy.ndarray, torch.Tensor]] = None, orientations: Optional[Union[numpy.ndarray, torch.Tensor]] = None, scales: Optional[Union[numpy.ndarray, torch.Tensor]] = None, visibilities: Optional[Union[numpy.ndarray, torch.Tensor]] = None, reset_xform_properties: bool = True)

Provides high level functions to deal with a Xform prim view (one or many) and its descendants as well as its attributes/properties.

This class wraps all matching Xforms found at the regex provided at the prim_paths_expr argument

Note

Each prim will have xformOp:orient, xformOp:translate and xformOp:scale only post-init, unless it is a non-root articulation link.

Parameters
  • prim_paths_expr (str) – prim paths regex to encapsulate all prims that match it. example: “/World/Env[1-5]/Franka” will match /World/Env1/Franka, /World/Env2/Franka..etc. (a non regex prim path can also be used to encapsulate one Xform).

  • name (str, optional) – shortname to be used as a key by Scene class. Note: needs to be unique if the object is added to the Scene. Defaults to “xform_prim_view”.

  • positions (Optional[Union[np.ndarray, torch.Tensor]], optional) – default positions in the world frame of the prim. shape is (N, 3). Defaults to None, which means left unchanged.

  • translations (Optional[Union[np.ndarray, torch.Tensor]], optional) – default translations in the local frame of the prims (with respect to its parent prims). shape is (N, 3). Defaults to None, which means left unchanged.

  • orientations (Optional[Union[np.ndarray, torch.Tensor]], optional) – default quaternion orientations in the world/ local frame of the prim (depends if translation or position is specified). quaternion is scalar-first (w, x, y, z). shape is (N, 4). Defaults to None, which means left unchanged.

  • scales (Optional[Union[np.ndarray, torch.Tensor]], optional) – local scales to be applied to the prim’s dimensions. shape is (N, 3). Defaults to None, which means left unchanged.

  • visibilities (Optional[Union[np.ndarray, torch.Tensor]], optional) – set to false for an invisible prim in the stage while rendering. shape is (N,). Defaults to None.

  • reset_xform_properties (bool, optional) – True if the prims don’t have the right set of xform properties (i.e: translate, orient and scale) ONLY and in that order. Set this parameter to False if the object were cloned using using the cloner api in omni.isaac.cloner. Defaults to True.

Raises
  • Exception – if translations and positions defined at the same time.

  • Exception – No prim was matched using the prim_paths_expr provided.

Example:

>>> import omni.isaac.core.utils.stage as stage_utils
>>> from omni.isaac.cloner import GridCloner
>>> from omni.isaac.core.prims import XFormPrimView
>>> from pxr import UsdGeom
>>>
>>> env_zero_path = "/World/envs/env_0"
>>> num_envs = 5
>>>
>>> # load the Franka Panda robot USD file
>>> stage_utils.add_reference_to_stage(usd_path, prim_path=f"{env_zero_path}/panda")  # /World/envs/env_0/panda
>>>
>>> # clone the environment (num_envs)
>>> cloner = GridCloner(spacing=1.5)
>>> cloner.define_base_env(env_zero_path)
>>> UsdGeom.Xform.Define(stage_utils.get_current_stage(), env_zero_path)
>>> env_pos = cloner.clone(
...     source_prim_path=env_zero_path,
...     prim_paths=cloner.generate_paths("/World/envs/env", num_envs),
...     copy_from_source=True
... )
>>>
>>> # wrap all Xforms
>>> prims = XFormPrimView(prim_paths_expr="/World/envs/env.*", name="xform_view")
>>> prims
<omni.isaac.core.prims.xform_prim_view.XFormPrimView object at 0x7f8ffd22ebc0>
apply_visual_materials(visual_materials: Union[omni.isaac.core.materials.visual_material.VisualMaterial, List[omni.isaac.core.materials.visual_material.VisualMaterial]], weaker_than_descendants: Optional[Union[bool, List[bool]]] = None, indices: Optional[Union[numpy.ndarray, list, torch.Tensor, warp.types.array]] = None) None

Apply visual material to the prims and optionally their prim descendants.

Parameters
  • visual_materials (Union[VisualMaterial, List[VisualMaterial]]) – visual materials to be applied to the prims. Currently supports PreviewSurface, OmniPBR and OmniGlass. If a list is provided then its size has to be equal the view’s size or indices size. If one material is provided it will be applied to all prims in the view.

  • weaker_than_descendants (Optional[Union[bool, List[bool]]], optional) – True if the material shouldn’t override the descendants materials, otherwise False. Defaults to False. If a list of visual materials is provided then a list has to be provided with the same size for this arg as well.

  • indices (Optional[Union[np.ndarray, list, torch.Tensor, wp.array]], optional) – indices to specify which prims to manipulate. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

Raises
  • Exception – length of visual materials != length of prims indexed

  • Exception – length of visual materials != length of weaker descendants bools arg

Example:

>>> from omni.isaac.core.materials import OmniGlass
>>>
>>> # create a dark-red glass visual material
>>> material = OmniGlass(
...     prim_path="/World/material/glass",  # path to the material prim to create
...     ior=1.25,
...     depth=0.001,
...     thin_walled=False,
...     color=np.array([0.5, 0.0, 0.0])
... )
>>> prims.apply_visual_materials(material)
property count: int
Returns

Number of prims encapsulated in this view.

Return type

int

Example:

>>> prims.count
5
get_applied_visual_materials(indices: Optional[Union[numpy.ndarray, list, torch.Tensor, warp.types.array]] = None) List[omni.isaac.core.materials.visual_material.VisualMaterial]

Get the current applied visual materials

Parameters

indices (Optional[Union[np.ndarray, list, torch.Tensor, wp.array]], optional) – indices to specify which prims to query. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

Returns

a list of the current applied visual materials to the prims if its type is currently supported.

Return type

List[VisualMaterial]

Example:

>>> # get all applied visual materials. Returned size is 5 for the example: 5 envs
>>> prims.get_applied_visual_materials()
[<omni.isaac.core.materials.omni_glass.OmniGlass object at 0x7f829c165de0>,
 <omni.isaac.core.materials.omni_glass.OmniGlass object at 0x7f829c165de0>,
 <omni.isaac.core.materials.omni_glass.OmniGlass object at 0x7f829c165de0>,
 <omni.isaac.core.materials.omni_glass.OmniGlass object at 0x7f829c165de0>,
 <omni.isaac.core.materials.omni_glass.OmniGlass object at 0x7f829c165de0>]
>>>
>>> # get the applied visual materials for the first, middle and last of the 5 envs. Returned size is 3
>>> prims.get_applied_visual_materials(indices=np.array([0, 2, 4]))
[<omni.isaac.core.materials.omni_glass.OmniGlass object at 0x7f829c165de0>,
 <omni.isaac.core.materials.omni_glass.OmniGlass object at 0x7f829c165de0>,
 <omni.isaac.core.materials.omni_glass.OmniGlass object at 0x7f829c165de0>]
get_default_state() omni.isaac.core.utils.types.XFormPrimViewState

Get the default states (positions and orientations) defined with the set_default_state method

Returns

returns the default state of the prims that is used after each reset.

Return type

XFormPrimViewState

Example:

>>> state = prims.get_default_state()
>>> state
<omni.isaac.core.utils.types.XFormPrimViewState object at 0x7f82f73e3070>
>>> state.positions
[[ 1.5  -0.75  0.  ]
 [ 1.5   0.75  0.  ]
 [ 0.   -0.75  0.  ]
 [ 0.    0.75  0.  ]
 [-1.5  -0.75  0.  ]]
>>> state.orientations
[[1. 0. 0. 0.]
 [1. 0. 0. 0.]
 [1. 0. 0. 0.]
 [1. 0. 0. 0.]
 [1. 0. 0. 0.]]
get_local_poses(indices: Optional[Union[numpy.ndarray, list, torch.Tensor, warp.types.array]] = None) Union[Tuple[numpy.ndarray, numpy.ndarray], Tuple[torch.Tensor, torch.Tensor], Tuple[warp.types.indexedarray, warp.types.indexedarray]]

Get prim poses in the view with respect to the local frame (the prim’s parent frame)

Parameters

indices (Optional[Union[np.ndarray, list, torch.Tensor, wp.array]], optional) – indices to specify which prims to query. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

Returns

first index is translations in the local frame of the prims. shape is (M, 3).

second index is quaternion orientations in the local frame of the prims. quaternion is scalar-first (w, x, y, z). shape is (M, 4).

Return type

Union[Tuple[np.ndarray, np.ndarray], Tuple[torch.Tensor, torch.Tensor], Tuple[wp.indexedarray, wp.indexedarray]]

Example:

>>> # get all prims poses with respect to the local frame.
>>> # Returned shape is position (5, 3) and orientation (5, 4) for the example: 5 envs
>>> positions, orientations = prims.get_local_poses()
>>> positions
[[ 1.5  -0.75  0.  ]
 [ 1.5   0.75  0.  ]
 [ 0.   -0.75  0.  ]
 [ 0.    0.75  0.  ]
 [-1.5  -0.75  0.  ]]
>>> orientations
[[1. 0. 0. 0.]
 [1. 0. 0. 0.]
 [1. 0. 0. 0.]
 [1. 0. 0. 0.]
 [1. 0. 0. 0.]]
>>>
>>> # get only the prims poses with respect to the local frame for the first, middle and last of the 5 envs.
>>> # Returned shape is position (3, 3) and orientation (3, 4) for the example: 3 envs selected
>>> positions, orientations = prims.get_local_poses(indices=np.array([0, 2, 4]))
>>> positions
[[ 1.5  -0.75  0.  ]
 [ 0.   -0.75  0.  ]
 [-1.5  -0.75  0.  ]]
>>> orientations
[[1. 0. 0. 0.]
 [1. 0. 0. 0.]
 [1. 0. 0. 0.]]
get_local_scales(indices: Optional[Union[numpy.ndarray, list, torch.Tensor, warp.types.array]] = None) Union[numpy.ndarray, torch.Tensor, warp.types.indexedarray]

Get prim scales in the view with respect to the local frame (the parent’s frame).

Parameters

indices (Optional[Union[np.ndarray, list, torch.Tensor, wp.array]], optional) – indices to specify which prims to query. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

Returns

scales applied to the prim’s dimensions in the local frame. shape is (M, 3).

Return type

Union[np.ndarray, torch.Tensor, wp.indexedarray]

Example:

>>> # get all prims scales with respect to the local frame.
>>> # Returned shape is (5, 3) for the example: 5 envs
>>> prims.get_local_scales()
[[1. 1. 1.]
 [1. 1. 1.]
 [1. 1. 1.]
 [1. 1. 1.]
 [1. 1. 1.]]
>>>
>>> # get only the prims scales with respect to the local frame for the first, middle and last of the 5 envs.
>>> # Returned shape is (3, 3) for the example: 3 envs selected
>>> prims.get_local_scales(indices=np.array([0, 2, 4]))
[[1. 1. 1.]
 [1. 1. 1.]
 [1. 1. 1.]]
get_visibilities(indices: Optional[Union[numpy.ndarray, list, torch.Tensor, warp.types.array]] = None) Union[numpy.ndarray, torch.Tensor, warp.types.indexedarray]

Returns the current visibilities of the prims in stage.

Parameters

indices (Optional[Union[np.ndarray, list, torch.Tensor, wp.array]], optional) – indices to specify which prims to query. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

Returns

Shape (M,) with type bool, where each item holds True

if the prim is visible in stage. False otherwise.

Return type

Union[np.ndarray, torch.Tensor, wp.indexedarray]

Example:

>>> # get all visibilities. Returned shape is (5,) for the example: 5 envs
>>> prims.get_visibilities()
[ True  True  True  True  True]
>>>
>>> # get the visibilities for the first, middle and last of the 5 envs. Returned shape is (3,)
>>> prims.get_visibilities(indices=np.array([0, 2, 4]))
[ True  True  True]
get_world_poses(indices: Optional[Union[numpy.ndarray, list, torch.Tensor, warp.types.array]] = None) Union[Tuple[numpy.ndarray, numpy.ndarray], Tuple[torch.Tensor, torch.Tensor], Tuple[warp.types.indexedarray, warp.types.indexedarray]]

Get the poses of the prims in the view with respect to the world’s frame

Parameters

indices (Optional[Union[np.ndarray, list, torch.Tensor, wp.array]], optional) – indices to specify which prims to query. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

Returns

first index is positions in the world frame of the prims. shape is (M, 3).

second index is quaternion orientations in the world frame of the prims. quaternion is scalar-first (w, x, y, z). shape is (M, 4).

Return type

Union[Tuple[np.ndarray, np.ndarray], Tuple[torch.Tensor, torch.Tensor], Tuple[wp.indexedarray, wp.indexedarray]]

Example:

>>> # get all prims poses with respect to the world's frame.
>>> # Returned shape is position (5, 3) and orientation (5, 4) for the example: 5 envs
>>> positions, orientations = prims.get_world_poses()
>>> positions
[[ 1.5  -0.75  0.  ]
 [ 1.5   0.75  0.  ]
 [ 0.   -0.75  0.  ]
 [ 0.    0.75  0.  ]
 [-1.5  -0.75  0.  ]]
>>> orientations
[[1. 0. 0. 0.]
 [1. 0. 0. 0.]
 [1. 0. 0. 0.]
 [1. 0. 0. 0.]
 [1. 0. 0. 0.]]
>>>
>>> # get only the prims poses with respect to the world's frame for the first, middle and last of the 5 envs.
>>> # Returned shape is position (3, 3) and orientation (3, 4) for the example: 3 envs selected
>>> positions, orientations = prims.get_world_poses(indices=np.array([0, 2, 4]))
>>> positions
[[ 1.5  -0.75  0.  ]
 [ 0.   -0.75  0.  ]
 [-1.5  -0.75  0.  ]]
>>> orientations
[[1. 0. 0. 0.]
 [1. 0. 0. 0.]
 [1. 0. 0. 0.]]
get_world_scales(indices: Optional[Union[numpy.ndarray, list, torch.Tensor, warp.types.array]] = None) Union[numpy.ndarray, torch.Tensor, warp.types.indexedarray]

Get prim scales in the view with respect to the world’s frame

Parameters

indices (Optional[Union[np.ndarray, list, torch.Tensor, wp.array]], optional) – indices to specify which prims to query. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

Returns

scales applied to the prim’s dimensions in the world frame. shape is (M, 3).

Return type

Union[np.ndarray, torch.Tensor, wp.indexedarray]

Example:

>>> # get all prims scales with respect to the world's frame.
>>> # Returned shape is (5, 3) for the example: 5 envs
>>> prims.get_world_scales()
[[1. 1. 1.]
 [1. 1. 1.]
 [1. 1. 1.]
 [1. 1. 1.]
 [1. 1. 1.]]
>>>
>>> # get only the prims scales with respect to the world's frame for the first, middle and last of the 5 envs.
>>> # Returned shape is (3, 3) for the example: 3 envs selected
>>> prims.get_world_scales(indices=np.array([0, 2, 4]))
[[1. 1. 1.]
 [1. 1. 1.]
 [1. 1. 1.]]
initialize(physics_sim_view: Optional[omni.physics.tensors.bindings._physicsTensors.SimulationView] = None) None

Create a physics simulation view if not passed and set other properties using the PhysX tensor API

Note

For this particular class, calling this method will do nothing

Parameters

physics_sim_view (omni.physics.tensors.SimulationView, optional) – current physics simulation view. Defaults to None.

Example:

>>> prims.initialize()

Returns: bool: True if the prim corresponds to a non root link in an articulation. Otherwise False.

is_valid(indices: Optional[Union[numpy.ndarray, list, torch.Tensor, warp.types.array]] = None) bool

Check that all prims have a valid USD Prim

Parameters

indices (Optional[Union[np.ndarray, list, torch.Tensor, wp.array]], optional) – indices to specify which prims to query. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

Returns

True if all prim paths specified in the view correspond to a valid prim in stage. False otherwise.

Return type

bool

Example:

>>> prims.is_valid()
True
is_visual_material_applied(indices: Optional[Union[numpy.ndarray, list, torch.Tensor, warp.types.array]] = None) List[bool]

Check if there is a visual material applied

Parameters

indices (Optional[Union[np.ndarray, list, torch.Tensor, wp.array]], optional) – indices to specify which prims to query. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

Returns

True if there is a visual material applied is applied to the corresponding prim in the view. False otherwise.

Return type

List[bool]

Example:

>>> # given a visual material that is applied only to the first and the last environment
>>> prims.is_visual_material_applied()
[True, False, False, False, True]
>>>
>>> # check for the first, middle and last of the 5 envs
>>> prims.is_visual_material_applied(indices=np.array([0, 2, 4]))
[True, False, True]
property name: str

Returns: str: name given to the prims view when instantiating it.

post_reset() None

Reset the prims to its default state (positions and orientations)

Example:

>>> prims.post_reset()
property prim_paths: List[str]
Returns

list of prim paths in the stage encapsulated in this view.

Return type

List[str]

Example:

>>> prims.prim_paths
['/World/envs/env_0', '/World/envs/env_1', '/World/envs/env_2', '/World/envs/env_3', '/World/envs/env_4']
property prims: List[pxr.Usd.Prim]
Returns

List of USD Prim objects encapsulated in this view.

Return type

List[Usd.Prim]

Example:

>>> prims.prims
[Usd.Prim(</World/envs/env_0>), Usd.Prim(</World/envs/env_1>), Usd.Prim(</World/envs/env_2>),
 Usd.Prim(</World/envs/env_3>), Usd.Prim(</World/envs/env_4>)]
set_default_state(positions: Optional[Union[numpy.ndarray, torch.Tensor, warp.types.array]] = None, orientations: Optional[Union[numpy.ndarray, torch.Tensor, warp.types.array]] = None, indices: Optional[Union[numpy.ndarray, list, torch.Tensor, warp.types.array]] = None) None

Set the default state of the prims (positions and orientations), that will be used after each reset.

Note

The default states will be set during post-reset (e.g., calling .post_reset() or world.reset() methods)

Parameters
  • positions (Optional[Union[np.ndarray, torch.Tensor, wp.array]], optional) – positions in the world frame of the prim. shape is (M, 3). Defaults to None, which means left unchanged.

  • orientations (Optional[Union[np.ndarray, torch.Tensor, wp.array]], optional) – quaternion orientations in the world frame of the prim. quaternion is scalar-first (w, x, y, z). shape is (M, 4). Defaults to None, which means left unchanged.

  • indices (Optional[Union[np.ndarray, list, torch.Tensor, wp.array]], optional) – indices to specify which prims to manipulate. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

Example:

>>> # configure default states for all prims
>>> positions = np.zeros((num_envs, 3))
>>> positions[:, 0] = np.arange(num_envs)
>>> orientations = np.tile(np.array([1.0, 0.0, 0.0, 0.0]), (num_envs, 1))
>>> prims.set_default_state(positions=positions, orientations=orientations)
>>>
>>> # set default states during post-reset
>>> prims.post_reset()
set_local_poses(translations: Optional[Union[numpy.ndarray, torch.Tensor, warp.types.array]] = None, orientations: Optional[Union[numpy.ndarray, torch.Tensor, warp.types.array]] = None, indices: Optional[Union[numpy.ndarray, list, torch.Tensor, warp.types.array]] = None) None

Set prim poses in the view with respect to the local frame (the prim’s parent frame)

Warning

This method will change (teleport) the prim poses immediately to the indicated value

Parameters
  • translations (Optional[Union[np.ndarray, torch.Tensor, wp.array]], optional) – translations in the local frame of the prims (with respect to its parent prim). shape is (M, 3). Defaults to None, which means left unchanged.

  • orientations (Optional[Union[np.ndarray, torch.Tensor, wp.array]], optional) – quaternion orientations in the local frame of the prims. quaternion is scalar-first (w, x, y, z). shape is (M, 4). Defaults to None, which means left unchanged.

  • indices (Optional[Union[np.ndarray, list, torch.Tensor, wp.array]], optional) – indices to specify which prims to manipulate. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

Hint

This method belongs to the methods used to set the prim state

Example:

>>> # reposition all prims
>>> positions = np.zeros((num_envs, 3))
>>> positions[:,0] = np.arange(num_envs)
>>> orientations = np.tile(np.array([1.0, 0.0, 0.0, 0.0]), (num_envs, 1))
>>> prims.set_local_poses(positions, orientations)
>>>
>>> # reposition only the prims for the first, middle and last of the 5 envs
>>> positions = np.zeros((3, 3))
>>> positions[:,1] = np.arange(3)
>>> orientations = np.tile(np.array([1.0, 0.0, 0.0, 0.0]), (3, 1))
>>> prims.set_local_poses(positions, orientations, indices=np.array([0, 2, 4]))
set_local_scales(scales: Optional[Union[numpy.ndarray, torch.Tensor, warp.types.array]], indices: Optional[Union[numpy.ndarray, list, torch.Tensor, warp.types.array]] = None) None

Set prim scales in the view with respect to the local frame (the prim’s parent frame)

Parameters
  • scales (Optional[Union[np.ndarray, torch.Tensor, wp.array]]) – scales to be applied to the prim’s dimensions in the view. shape is (M, 3).

  • indices (Optional[Union[np.ndarray, list, torch.Tensor, wp.array]], optional) – indices to specify which prims to manipulate. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

Example:

>>> # set the scale for all prims. Since there are 5 envs, the scale is repeated 5 times
>>> scales = np.tile(np.array([1.0, 0.75, 0.5]), (num_envs, 1))
>>> prims.set_local_scales(scales)
>>>
>>> # set the scale for the first, middle and last of the 5 envs
>>> scales = np.tile(np.array([1.0, 0.75, 0.5]), (3, 1))
>>> prims.set_local_scales(scales, indices=np.array([0, 2, 4]))
set_visibilities(visibilities: Union[numpy.ndarray, torch.Tensor, warp.types.array], indices: Optional[Union[numpy.ndarray, list, torch.Tensor, warp.types.array]] = None) None

Set the visibilities of the prims in stage

Parameters
  • visibilities (Union[np.ndarray, torch.Tensor, wp.array]) – flag to set the visibilities of the usd prims in stage. Shape (M,). Where M <= size of the encapsulated prims in the view.

  • indices (Optional[Union[np.ndarray, list, torch.Tensor, wp.array]], optional) – indices to specify which prims to manipulate. Shape (M,). Defaults to None (i.e: all prims in the view).

Example:

>>> # make all prims not visible in the stage
>>> prims.set_visibilities(visibilities=[False] * num_envs)
set_world_poses(positions: Optional[Union[numpy.ndarray, torch.Tensor, warp.types.array]] = None, orientations: Optional[Union[numpy.ndarray, torch.Tensor, warp.types.array]] = None, indices: Optional[Union[numpy.ndarray, list, torch.Tensor, warp.types.array]] = None) None

Set prim poses in the view with respect to the world’s frame

Warning

This method will change (teleport) the prim poses immediately to the indicated value

Parameters
  • positions (Optional[Union[np.ndarray, torch.Tensor, wp.array]], optional) – positions in the world frame of the prims. shape is (M, 3). Defaults to None, which means left unchanged.

  • orientations (Optional[Union[np.ndarray, torch.Tensor, wp.array]], optional) – quaternion orientations in the world frame of the prims. quaternion is scalar-first (w, x, y, z). shape is (M, 4). Defaults to None, which means left unchanged.

  • indices (Optional[Union[np.ndarray, list, torch.Tensor, wp.array]], optional) – indices to specify which prims to query. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

Hint

This method belongs to the methods used to set the prim state

Example:

>>> # reposition all prims in row (x-axis)
>>> positions = np.zeros((num_envs, 3))
>>> positions[:,0] = np.arange(num_envs)
>>> orientations = np.tile(np.array([1.0, 0.0, 0.0, 0.0]), (num_envs, 1))
>>> prims.set_world_poses(positions, orientations)
>>>
>>> # reposition only the prims for the first, middle and last of the 5 envs in column (y-axis)
>>> positions = np.zeros((3, 3))
>>> positions[:,1] = np.arange(3)
>>> orientations = np.tile(np.array([1.0, 0.0, 0.0, 0.0]), (3, 1))
>>> prims.set_world_poses(positions, orientations, indices=np.array([0, 2, 4]))

Geometry Prim

class GeometryPrim(prim_path: str, name: str = 'geometry_prim', position: Optional[Sequence[float]] = None, translation: Optional[Sequence[float]] = None, orientation: Optional[Sequence[float]] = None, scale: Optional[Sequence[float]] = None, visible: Optional[bool] = None, collision: bool = False, track_contact_forces: bool = False, prepare_contact_sensor: bool = False, disable_stablization: bool = True, contact_filter_prim_paths_expr: Optional[List[str]] = [])

High level wrapper to deal with a Geom prim (only one geometry prim) and its attributes/properties.

The prim_path should correspond to type UsdGeom.Cube, UsdGeom.Capsule, UsdGeom.Cone, UsdGeom.Cylinder, UsdGeom.Sphere or UsdGeom.Mesh.

Warning

The geometry object must be initialized in order to be able to operate on it. See the initialize method for more details.

Warning

Some methods require the prim to have the Physx Collision API. Instantiate the class with the collision parameter to True to apply the collision API.

Parameters
  • prim_path (str) – prim path of the Prim to encapsulate or create.

  • name (str, optional) – shortname to be used as a key by Scene class. Note: needs to be unique if the object is added to the Scene. Defaults to “xform_prim”.

  • position (Optional[Sequence[float]], optional) – position in the world frame of the prim. shape is (3, ). Defaults to None, which means left unchanged.

  • translation (Optional[Sequence[float]], optional) – translation in the local frame of the prim (with respect to its parent prim). shape is (3, ). Defaults to None, which means left unchanged.

  • orientation (Optional[Sequence[float]], optional) – quaternion orientation in the world/ local frame of the prim (depends if translation or position is specified). quaternion is scalar-first (w, x, y, z). shape is (4, ). Defaults to None, which means left unchanged.

  • scale (Optional[Sequence[float]], optional) – local scale to be applied to the prim’s dimensions. shape is (3, ). Defaults to None, which means left unchanged.

  • visible (bool, optional) – set to false for an invisible prim in the stage while rendering. Defaults to True.

  • collision (bool, optional) – Set to True if the geometry should have a collider (i.e not only a visual geometry). Defaults to False.

  • track_contact_forces (bool, Optional) – if enabled, the view will track the net contact forces on each geometry prim in the view. Note that the collision flag should be set to True to report contact forces. Defaults to False.

  • prepare_contact_sensors (bool, Optional) – applies contact reporter API to the prim if it already does not have one. Defaults to False.

  • disable_stablization (bool, optional) – disables the contact stabilization parameter in the physics context. Defaults to True.

  • contact_filter_prim_paths_expr (Optional[List[str]], Optional) – a list of filter expressions which allows for tracking contact forces between the geometry prim and this subset through get_contact_force_matrix().

Example:

>>> import omni.isaac.core.utils.stage as stage_utils
>>> from omni.isaac.core.prims import GeometryPrim
>>>
>>> # create a Cube at the given path
>>> stage_utils.get_current_stage().DefinePrim("/World/Xform", "Xform")
>>> stage_utils.get_current_stage().DefinePrim("/World/Xform/Cube", "Cube")
>>>
>>> # wrap the prim as geometry prim
>>> prim = GeometryPrim("/World/Xform", collision=True)
>>> prim
<omni.isaac.core.prims.geometry_prim.GeometryPrim object at 0x7fe960247400>
apply_physics_material(physics_material: omni.isaac.core.materials.physics_material.PhysicsMaterial, weaker_than_descendants: bool = False)

Used to apply physics material to the held prim and optionally its descendants.

Parameters
  • physics_material (PhysicsMaterial) – physics material to be applied to the held prim. This where you want to define friction, restitution..etc. Note: if a physics material is not defined, the defaults will be used from PhysX.

  • weaker_than_descendants (bool, optional) – True if the material shouldn’t override the descendants materials, otherwise False. Defaults to False.

Example:

>>> from omni.isaac.core.materials import PhysicsMaterial
>>>
>>> # create a rigid body physical material
>>> material = PhysicsMaterial(
...     prim_path="/World/physics_material/aluminum",  # path to the material prim to create
...     dynamic_friction=0.4,
...     static_friction=1.1,
...     restitution=0.1
... )
>>> prim.apply_physics_material(material)
apply_visual_material(visual_material: omni.isaac.core.materials.visual_material.VisualMaterial, weaker_than_descendants: bool = False) None

Apply visual material to the held prim and optionally its descendants.

Parameters
  • visual_material (VisualMaterial) – visual material to be applied to the held prim. Currently supports PreviewSurface, OmniPBR and OmniGlass.

  • weaker_than_descendants (bool, optional) – True if the material shouldn’t override the descendants materials, otherwise False. Defaults to False.

Example:

>>> from omni.isaac.core.materials import OmniGlass
>>>
>>> # create a dark-red glass visual material
>>> material = OmniGlass(
...     prim_path="/World/material/glass",  # path to the material prim to create
...     ior=1.25,
...     depth=0.001,
...     thin_walled=False,
...     color=np.array([0.5, 0.0, 0.0])
... )
>>> prim.apply_visual_material(material)
property geom: pxr.UsdGeom.Gprim

Returns: UsdGeom.Gprim: USD geometry object encapsulated.

get_applied_physics_material() omni.isaac.core.materials.physics_material.PhysicsMaterial

Return the current applied physics material in case it was applied using apply_physics_material or not.

Returns

the current applied physics material.

Return type

PhysicsMaterial

Example:

>>> # given a physics material applied
>>> prim.get_applied_physics_material()
<omni.isaac.core.materials.physics_material.PhysicsMaterial object at 0x7fb66c30cd30>
get_applied_visual_material() omni.isaac.core.materials.visual_material.VisualMaterial

Return the current applied visual material in case it was applied using apply_visual_material or it’s one of the following materials that was already applied before: PreviewSurface, OmniPBR and OmniGlass.

Returns

the current applied visual material if its type is currently supported.

Return type

VisualMaterial

Example:

>>> # given a visual material applied
>>> prim.get_applied_visual_material()
<omni.isaac.core.materials.omni_glass.OmniGlass object at 0x7f36263106a0>
get_collision_approximation() str

Get the collision approximation

Approximation

Full name

Description

"none"

Triangle Mesh

The mesh geometry is used directly as a collider without any approximation

"convexDecomposition"

Convex Decomposition

A convex mesh decomposition is performed. This results in a set of convex mesh colliders

"convexHull"

Convex Hull

A convex hull of the mesh is generated and used as the collider

"boundingSphere"

Bounding Sphere

A bounding sphere is computed around the mesh and used as a collider

"boundingCube"

Bounding Cube

An optimally fitting box collider is computed around the mesh

"meshSimplification"

Mesh Simplification

A mesh simplification step is performed, resulting in a simplified triangle mesh collider

"sdf"

SDF Mesh

SDF (Signed-Distance-Field) use high-detail triangle meshes as collision shape

"sphereFill"

Sphere Approximation

A sphere mesh decomposition is performed. This results in a set of sphere colliders

Returns

approximation used for collision

Return type

str

Example:

>>> prim.get_collision_approximation()
none
get_collision_enabled() bool

Check if the Collision API is enabled

Returns

True if the Collision API is enabled. Otherwise False

Return type

bool

Example:

>>> prim.get_collision_enabled()
True
get_contact_force_matrix(dt: float = 1.0) Union[numpy.ndarray, torch.Tensor]

If the object is initialized with filter_paths_expr list, this method returns the contact forces between the prims in the view and the filter prims. i.e., a matrix of dimension (self._contact_view.num_filters, 3) where num_filters is the determined according to the filter_paths_expr parameter.

Parameters

dt (float) – time step multiplier to convert the underlying impulses to forces. If the default value is used then the forces are in fact contact impulses

Returns

Net contact forces of the prims with shape (self._geometry_prim_view._contact_view.num_filters, 3).

Return type

Union[np.ndarray, torch.Tensor]

get_contact_offset() float

Get the contact offset

Shapes whose distance is less than the sum of their contact offset values will generate contacts

Search for Advanced Collision Detection in PhysX docs for more details

Returns

contact offset of the collision shape. Default value is -inf, means default is picked by simulation.

Return type

float

Example:

>>> prim.get_contact_offset()
-inf
get_default_state() omni.isaac.core.utils.types.XFormPrimState

Get the default prim states (spatial position and orientation).

Returns

an object that contains the default state of the prim (position and orientation)

Return type

XFormPrimState

Example:

>>> state = prim.get_default_state()
>>> state
<omni.isaac.core.utils.types.XFormPrimState object at 0x7f33addda650>
>>>
>>> state.position
[-4.5299529e-08 -1.8347054e-09 -2.8610229e-08]
>>> state.orientation
[1. 0. 0. 0.]
get_local_pose() Tuple[numpy.ndarray, numpy.ndarray]

Get prim’s pose with respect to the local frame (the prim’s parent frame)

Returns

first index is the position in the local frame (with shape (3, )). Second index is quaternion orientation (with shape (4, )) in the local frame

Return type

Tuple[np.ndarray, np.ndarray]

Example:

>>> # if the prim is in position (1.0, 0.5, 0.0) with respect to the world frame
>>> position, orientation = prim.get_local_pose()
>>> position
[0. 0. 0.]
>>> orientation
[0. 0. 0.]
get_local_scale() numpy.ndarray

Get prim’s scale with respect to the local frame (the parent’s frame)

Returns

scale applied to the prim’s dimensions in the local frame. shape is (3, ).

Return type

np.ndarray

Example:

>>> prim.get_local_scale()
[1. 1. 1.]
get_min_torsional_patch_radius() float

Get the minimum radius of the contact patch used to apply torsional friction

Search for “Torsional Patch Radius” in PhysX docs for more details

Returns

minimum radius of the contact patch used to apply torsional friction. Allowed range [0, max_float].

Return type

float

Example:

>>> prim.get_min_torsional_patch_radius()
0.0
get_net_contact_forces(dt: float = 1.0) Union[numpy.ndarray, torch.Tensor]

If contact forces of the prims in the view are tracked, this method returns the net contact forces on prims. i.e., a matrix of dimension (1, 3)

Parameters

dt (float) – time step multiplier to convert the underlying impulses to forces. If the default value is used then the forces are in fact contact impulses

Returns

Net contact forces of the prims with shape (3).

Return type

Union[np.ndarray, torch.Tensor]

get_rest_offset() float

Get the rest offset

Two shapes will come to rest at a distance equal to the sum of their rest offset values. If the rest offset is 0, they should converge to touching exactly

Search for Advanced Collision Detection in PhysX docs for more details

Returns

rest offset of the collision shape.

Return type

float

Example:

>>> prim.get_rest_offset()
-inf
get_torsional_patch_radius() float

Get the radius of the contact patch used to apply torsional friction

Search for “Torsional Patch Radius” in PhysX docs for more details

Returns

radius of the contact patch used to apply torsional friction. Allowed range [0, max_float].

Return type

float

Example:

>>> prim.get_torsional_patch_radius()
0.0
get_visibility() bool
Returns

true if the prim is visible in stage. false otherwise.

Return type

bool

Example:

>>> # get the visible state of an visible prim on the stage
>>> prim.get_visibility()
True
get_world_pose() Tuple[numpy.ndarray, numpy.ndarray]

Get prim’s pose with respect to the world’s frame

Returns

first index is the position in the world frame (with shape (3, )). Second index is quaternion orientation (with shape (4, )) in the world frame

Return type

Tuple[np.ndarray, np.ndarray]

Example:

>>> # if the prim is in position (1.0, 0.5, 0.0) with respect to the world frame
>>> position, orientation = prim.get_world_pose()
>>> position
[1.  0.5 0. ]
>>> orientation
[1. 0. 0. 0.]
get_world_scale() numpy.ndarray

Get prim’s scale with respect to the world’s frame

Returns

scale applied to the prim’s dimensions in the world frame. shape is (3, ).

Return type

np.ndarray

Example:

>>> prim.get_world_scale()
[1. 1. 1.]
initialize(physics_sim_view=None) None

Create a physics simulation view if not passed and using PhysX tensor API

Note

If the prim has been added to the world scene (e.g., world.scene.add(prim)), it will be automatically initialized when the world is reset (e.g., world.reset()).

Parameters

physics_sim_view (omni.physics.tensors.SimulationView, optional) – current physics simulation view. Defaults to None.

Example:

>>> prim.initialize()
is_valid() bool

Check if the prim path has a valid USD Prim at it

Returns

True is the current prim path corresponds to a valid prim in stage. False otherwise.

Return type

bool

Example:

>>> # given an existing and valid prim
>>> prims.is_valid()
True
is_visual_material_applied() bool

Check if there is a visual material applied

Returns

True if there is a visual material applied. False otherwise.

Return type

bool

Example:

>>> # given a visual material applied
>>> prim.is_visual_material_applied()
True
property name: Optional[str]

Returns: str: name given to the prim when instantiating it. Otherwise None.

Used to query if the prim is a non root articulation link

Returns

True if the prim itself is a non root link

Return type

bool

Example:

>>> # for a wrapped articulation (where the root prim has the Physics Articulation Root property applied)
>>> prim.non_root_articulation_link
False
post_reset() None

Reset the prim to its default state (position and orientation).

Note

For an articulation, in addition to configuring the root prim’s default position and spatial orientation (defined via the set_default_state method), the joint’s positions, velocities, and efforts (defined via the set_joints_default_state method) are imposed

Example:

>>> prim.post_reset()
property prim: pxr.Usd.Prim

Returns: Usd.Prim: USD Prim object that this object holds.

property prim_path: str

Returns: str: prim path in the stage

set_collision_approximation(approximation_type: str) None

Set the collision approximation

Approximation

Full name

Description

"none"

Triangle Mesh

The mesh geometry is used directly as a collider without any approximation

"convexDecomposition"

Convex Decomposition

A convex mesh decomposition is performed. This results in a set of convex mesh colliders

"convexHull"

Convex Hull

A convex hull of the mesh is generated and used as the collider

"boundingSphere"

Bounding Sphere

A bounding sphere is computed around the mesh and used as a collider

"boundingCube"

Bounding Cube

An optimally fitting box collider is computed around the mesh

"meshSimplification"

Mesh Simplification

A mesh simplification step is performed, resulting in a simplified triangle mesh collider

"sdf"

SDF Mesh

SDF (Signed-Distance-Field) use high-detail triangle meshes as collision shape

"sphereFill"

Sphere Approximation

A sphere mesh decomposition is performed. This results in a set of sphere colliders

Note

Use Convex Decomposition or SDF (Signed-Distance-Field) tri-meshes to capture details better

Warning

Switching to Convex Decomposition or SDF (Signed-Distance-Field) will have a simulation performance impact due to higher computational cost

Parameters

approximation_type (str) – approximation used for collision

Example:

>>> prim.set_collision_approximation("convexDecomposition")
set_collision_enabled(enabled: bool) None

Enable/disable the Collision API

Parameters

enabled (bool) – Whether to enable or disable the Collision API

Example:

>>> # disable collisions
>>> prim.set_collision_enabled(False)
set_contact_offset(offset: float) None

Set the contact offset

Shapes whose distance is less than the sum of their contact offset values will generate contacts

Search for Advanced Collision Detection in PhysX docs for more details

Warning

The contact offset must be positive and greater than the rest offset

Parameters

offset (float) – Contact offset of a collision shape. Allowed range [maximum(0, rest_offset), 0]. Default value is -inf, means default is picked by simulation based on the shape extent.

Example:

>>> prim.set_contact_offset(0.02)
set_default_state(position: Optional[Sequence[float]] = None, orientation: Optional[Sequence[float]] = None) None

Set the default state of the prim (position and orientation), that will be used after each reset.

Parameters
  • position (Optional[Sequence[float]], optional) – position in the world frame of the prim. shape is (3, ). Defaults to None, which means left unchanged.

  • orientation (Optional[Sequence[float]], optional) – quaternion orientation in the world frame of the prim. quaternion is scalar-first (w, x, y, z). shape is (4, ). Defaults to None, which means left unchanged.

Example:

>>> # configure default state
>>> prim.set_default_state(position=np.array([1.0, 0.5, 0.0]), orientation=np.array([1, 0, 0, 0]))
>>>
>>> # set default states during post-reset
>>> prim.post_reset()
set_local_pose(translation: Optional[Sequence[float]] = None, orientation: Optional[Sequence[float]] = None) None

Set prim’s pose with respect to the local frame (the prim’s parent frame).

Warning

This method will change (teleport) the prim pose immediately to the indicated value

Parameters
  • translation (Optional[Sequence[float]], optional) – translation in the local frame of the prim (with respect to its parent prim). shape is (3, ). Defaults to None, which means left unchanged.

  • orientation (Optional[Sequence[float]], optional) – quaternion orientation in the local frame of the prim. quaternion is scalar-first (w, x, y, z). shape is (4, ). Defaults to None, which means left unchanged.

Hint

This method belongs to the methods used to set the prim state

Example:

>>> prim.set_local_pose(translation=np.array([1.0, 0.5, 0.0]), orientation=np.array([1., 0., 0., 0.]))
set_local_scale(scale: Optional[Sequence[float]]) None

Set prim’s scale with respect to the local frame (the prim’s parent frame).

Parameters

scale (Optional[Sequence[float]]) – scale to be applied to the prim’s dimensions. shape is (3, ). Defaults to None, which means left unchanged.

Example:

>>> # scale prim 10 times smaller
>>> prim.set_local_scale(np.array([0.1, 0.1, 0.1]))
set_min_torsional_patch_radius(radius: float) None

Set the minimum radius of the contact patch used to apply torsional friction

Search for “Torsional Patch Radius” in PhysX docs for more details

Parameters

radius (float) – minimum radius of the contact patch used to apply torsional friction. Allowed range [0, max_float].

Example:

>>> prim.set_min_torsional_patch_radius(0.05)
set_rest_offset(offset: float) None

Set the rest offset

Two shapes will come to rest at a distance equal to the sum of their rest offset values. If the rest offset is 0, they should converge to touching exactly

Search for Advanced Collision Detection in PhysX docs for more details

Warning

The contact offset must be positive and greater than the rest offset

Parameters

offset (float) – Rest offset of a collision shape. Allowed range [-max_float, contact_offset. Default value is -inf, means default is picked by simulation. For rigid bodies its zero.

Example:

>>> prim.set_rest_offset(0.01)
set_torsional_patch_radius(radius: float) None

Set the radius of the contact patch used to apply torsional friction

Search for “Torsional Patch Radius” in PhysX docs for more details

Parameters

radius (float) – radius of the contact patch used to apply torsional friction. Allowed range [0, max_float].

Example:

>>> prim.set_torsional_patch_radius(0.1)
set_visibility(visible: bool) None

Set the visibility of the prim in stage

Parameters

visible (bool) – flag to set the visibility of the usd prim in stage.

Example:

>>> # make prim not visible in the stage
>>> prim.set_visibility(visible=False)
set_world_pose(position: Optional[Sequence[float]] = None, orientation: Optional[Sequence[float]] = None) None

Ses prim’s pose with respect to the world’s frame

Warning

This method will change (teleport) the prim pose immediately to the indicated value

Parameters
  • position (Optional[Sequence[float]], optional) – position in the world frame of the prim. shape is (3, ). Defaults to None, which means left unchanged.

  • orientation (Optional[Sequence[float]], optional) – quaternion orientation in the world frame of the prim. quaternion is scalar-first (w, x, y, z). shape is (4, ). Defaults to None, which means left unchanged.

Hint

This method belongs to the methods used to set the prim state

Example:

>>> prim.set_world_pose(position=np.array([1.0, 0.5, 0.0]), orientation=np.array([1., 0., 0., 0.]))

Geometry Prim View

class GeometryPrimView(prim_paths_expr: str, name: str = 'geometry_prim_view', positions: Optional[Union[numpy.ndarray, torch.Tensor, warp.types.array]] = None, translations: Optional[Union[numpy.ndarray, torch.Tensor, warp.types.array]] = None, orientations: Optional[Union[numpy.ndarray, torch.Tensor, warp.types.array]] = None, scales: Optional[Union[numpy.ndarray, torch.Tensor, warp.types.array]] = None, visibilities: Optional[Union[numpy.ndarray, torch.Tensor, warp.types.array]] = None, reset_xform_properties: bool = True, collisions: Optional[Union[numpy.ndarray, torch.Tensor, warp.types.array]] = None, track_contact_forces: bool = False, prepare_contact_sensors: bool = False, disable_stablization: bool = True, contact_filter_prim_paths_expr: Optional[List[str]] = [], max_contact_count: int = 0)

High level wrapper to deal with geom prims (one or many) as well as their attributes/properties.

This class wraps all matching geom prims found at the regex provided at the prim_paths_expr argument

Note

Each prim will have xformOp:orient, xformOp:translate and xformOp:scale only post-init, unless it is a non-root articulation link.

Warning

The geometry prim view object must be initialized in order to be able to operate on it. See the initialize method for more details.

Warning

Some methods require the prims to have the Physx Collision API. Instantiate the class with the collision parameter to a list of True values to apply the collision API.

Parameters
  • prim_paths_expr (str) – prim paths regex to encapsulate all prims that match it. example: “/World/Env[1-5]/Microwave” will match /World/Env1/Microwave, /World/Env2/Microwave..etc. (a non regex prim path can also be used to encapsulate one XForm).

  • name (str, optional) – shortname to be used as a key by Scene class. Note: needs to be unique if the object is added to the Scene. Defaults to “geometry_prim_view”.

  • positions (Optional[Union[np.ndarray, torch.Tensor, wp.array]], optional) – default positions in the world frame of the prim. shape is (N, 3). Defaults to None, which means left unchanged.

  • translations (Optional[Union[np.ndarray, torch.Tensor, wp.array]], optional) – default translations in the local frame of the prims (with respect to its parent prims). shape is (N, 3). Defaults to None, which means left unchanged.

  • orientations (Optional[Union[np.ndarray, torch.Tensor, wp.array]], optional) – default quaternion orientations in the world/ local frame of the prim (depends if translation or position is specified). quaternion is scalar-first (w, x, y, z). shape is (N, 4). Defaults to None, which means left unchanged.

  • scales (Optional[Union[np.ndarray, torch.Tensor, wp.array]], optional) – local scales to be applied to the prim’s dimensions. shape is (N, 3). Defaults to None, which means left unchanged.

  • visibilities (Optional[Union[np.ndarray, torch.Tensor, wp.array], optional) – set to false for an invisible prim in the stage while rendering. shape is (N,). Defaults to None.

  • reset_xform_properties (bool, optional) – True if the prims don’t have the right set of xform properties (i.e: translate, orient and scale) ONLY and in that order. Set this parameter to False if the object were cloned using using the cloner api in omni.isaac.cloner. Defaults to True.

  • collisions (Optional[Union[np.ndarray, torch.Tensor, wp.array]], optional) – Set to True if the geometry already have/ should have a collider (i.e not only a visual geometry). shape is (N,). Defaults to None.

  • track_contact_forces (bool, Optional) – if enabled, the view will track the net contact forces on each geometry prim in the view. Note that the collision flag should be set to True to report contact forces. Defaults to False.

  • prepare_contact_sensors (bool, Optional) – applies contact reporter API to the prim if it already does not have one. Defaults to False.

  • disable_stablization (bool, optional) – disables the contact stabilization parameter in the physics context. Defaults to True.

  • contact_filter_prim_paths_expr (Optional[List[str]], Optional) – a list of filter expressions which allows for tracking contact forces between the geometry prim and this subset through get_contact_force_matrix().

  • max_contact_count (int, optional) – maximum number of contact data to report when detailed contact information is needed

Example:

>>> import omni.isaac.core.utils.stage as stage_utils
>>> from omni.isaac.cloner import GridCloner
>>> from omni.isaac.core.prims import GeometryPrimView
>>> from pxr import UsdGeom
>>>
>>> env_zero_path = "/World/envs/env_0"
>>> num_envs = 5
>>>
>>> # clone the environment (num_envs)
>>> cloner = GridCloner(spacing=1.5)
>>> cloner.define_base_env(env_zero_path)
>>> UsdGeom.Xform.Define(stage_utils.get_current_stage(), env_zero_path)
>>> stage_utils.get_current_stage().DefinePrim(f"{env_zero_path}/Xform", "Xform")
>>> stage_utils.get_current_stage().DefinePrim(f"{env_zero_path}/Xform/Cube", "Cube")
>>> env_pos = cloner.clone(
...     source_prim_path=env_zero_path,
...     prim_paths=cloner.generate_paths("/World/envs/env", num_envs),
...     copy_from_source=True
... )
>>>
>>> # wrap the prims
>>> prims = GeometryPrimView(
...     prim_paths_expr="/World/envs/env.*/Xform",
...     name="geometry_prim_view",
...     collisions=[True] * num_envs
... )
>>> prims
<omni.isaac.core.prims.geometry_prim_view.GeometryPrimView object at 0x7f372bb21630>
apply_collision_apis(indices: Optional[Union[numpy.ndarray, list, torch.Tensor, warp.types.array]] = None) None

Apply the collision API to prims in the view and update internal variables

Parameters

indices (Optional[Union[np.ndarray, list, torch.Tensor, wp.array]], optional) – indices to specify which prims to manipulate. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

Example:

>>> # apply the collision API for all prims
>>> prims.apply_collision_apis()
>>>
>>> # apply the collision API for the first, middle and last of the 5 envs
>>> prims.apply_collision_apis(indices=np.array([0, 2, 4]))
apply_physics_materials(physics_materials: Union[omni.isaac.core.materials.physics_material.PhysicsMaterial, List[omni.isaac.core.materials.physics_material.PhysicsMaterial]], weaker_than_descendants: Optional[Union[bool, List[bool]]] = None, indices: Optional[Union[numpy.ndarray, list, torch.Tensor, warp.types.array]] = None) None

Used to apply physics material to prims in the view and optionally its descendants.

Parameters
  • physics_materials (Union[PhysicsMaterial, List[PhysicsMaterial]]) – physics materials to be applied to prims in the view. Physics material can be used to define friction, restitution..etc. Note: if a physics material is not defined, the defaults will be used from PhysX. If a list is provided then its size has to be equal the view’s size or indices size. If one material is provided it will be applied to all prims in the view.

  • weaker_than_descendants (Optional[Union[bool, List[bool]]], optional) – True if the material shouldn’t override the descendants materials, otherwise False. Defaults to False. If a list of visual materials is provided then a list has to be provided with the same size for this arg as well.

  • indices (Optional[Union[np.ndarray, list, torch.Tensor, wp.array]], optional) – indices to specify which prims to manipulate. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

Raises
  • Exception – length of physics materials != length of prims indexed

  • Exception – length of physics materials != length of weaker descendants arg

Example:

>>> from omni.isaac.core.materials import PhysicsMaterial
>>>
>>> # create a rigid body physical material
>>> material = PhysicsMaterial(
...     prim_path="/World/physics_material/aluminum",  # path to the material prim to create
...     dynamic_friction=0.4,
...     static_friction=1.1,
...     restitution=0.1
... )
>>>
>>> # apply the material to all prims
>>> prims.apply_physics_materials(material)  # or [material] * num_envs
>>>
>>> # apply the collision API for the first, middle and last of the 5 envs
>>> prims.apply_physics_materials(material, indices=np.array([0, 2, 4]))
apply_visual_materials(visual_materials: Union[omni.isaac.core.materials.visual_material.VisualMaterial, List[omni.isaac.core.materials.visual_material.VisualMaterial]], weaker_than_descendants: Optional[Union[bool, List[bool]]] = None, indices: Optional[Union[numpy.ndarray, list, torch.Tensor, warp.types.array]] = None) None

Apply visual material to the prims and optionally their prim descendants.

Parameters
  • visual_materials (Union[VisualMaterial, List[VisualMaterial]]) – visual materials to be applied to the prims. Currently supports PreviewSurface, OmniPBR and OmniGlass. If a list is provided then its size has to be equal the view’s size or indices size. If one material is provided it will be applied to all prims in the view.

  • weaker_than_descendants (Optional[Union[bool, List[bool]]], optional) – True if the material shouldn’t override the descendants materials, otherwise False. Defaults to False. If a list of visual materials is provided then a list has to be provided with the same size for this arg as well.

  • indices (Optional[Union[np.ndarray, list, torch.Tensor, wp.array]], optional) – indices to specify which prims to manipulate. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

Raises
  • Exception – length of visual materials != length of prims indexed

  • Exception – length of visual materials != length of weaker descendants bools arg

Example:

>>> from omni.isaac.core.materials import OmniGlass
>>>
>>> # create a dark-red glass visual material
>>> material = OmniGlass(
...     prim_path="/World/material/glass",  # path to the material prim to create
...     ior=1.25,
...     depth=0.001,
...     thin_walled=False,
...     color=np.array([0.5, 0.0, 0.0])
... )
>>> prims.apply_visual_materials(material)
property count: int
Returns

Number of prims encapsulated in this view.

Return type

int

Example:

>>> prims.count
5
disable_collision(indices: Optional[Union[numpy.ndarray, list, torch.Tensor, warp.types.array]] = None) None

Disables collision on prims in the view.

Parameters

indices (Optional[Union[np.ndarray, list, torch.Tensor, wp.array]], optional) – indices to specify which prims to manipulate. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

Example:

>>> # disable the collision API for all prims
>>> prims.disable_collision()
>>>
>>> # disable the collision API for the prims for the first, middle and last of the 5 envs
>>> prims.disable_collision(indices=np.array([0, 2, 4]))
enable_collision(indices: Optional[Union[numpy.ndarray, list, torch.Tensor, warp.types.array]] = None) None

Enables collision on prims in the view.

Parameters

indices (Optional[Union[np.ndarray, list, torch.Tensor, wp.array]], optional) – indices to specify which prims to manipulate. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

Example:

>>> # enable the collision API for all prims
>>> prims.enable_collision()
>>>
>>> # enable the collision API for the prims for the first, middle and last of the 5 envs
>>> prims.enable_collision(indices=np.array([0, 2, 4]))
property geoms: List[pxr.UsdGeom.Gprim]
Returns

USD geom objects encapsulated.

Return type

List[UsdGeom.Gprim]

Example:

>>> prims.geoms
[UsdGeom.Gprim(Usd.Prim(</World/envs/env_0/Xform>)), UsdGeom.Gprim(Usd.Prim(</World/envs/env_1/Xform>)),
 UsdGeom.Gprim(Usd.Prim(</World/envs/env_2/Xform>)), UsdGeom.Gprim(Usd.Prim(</World/envs/env_3/Xform>)),
 UsdGeom.Gprim(Usd.Prim(</World/envs/env_4/Xform>))]
get_applied_physics_materials(indices: Optional[Union[numpy.ndarray, list, torch.Tensor, warp.types.array]] = None) List[omni.isaac.core.materials.physics_material.PhysicsMaterial]

Get the applied physics material to prims in the view.

Parameters

indices (Optional[Union[np.ndarray, list, torch.Tensor, wp.array]], optional) – indices to specify which prims to query. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

Returns

the current applied physics materials for prims in the view.

Return type

List[PhysicsMaterial]

Example:

>>> # get the applied material for all prims
>>> prims.get_applied_physics_materials()
[<omni.isaac.core.materials.physics_material.PhysicsMaterial object at 0x7f720859ece0>,
 <omni.isaac.core.materials.physics_material.PhysicsMaterial object at 0x7f720859ece0>,
 <omni.isaac.core.materials.physics_material.PhysicsMaterial object at 0x7f720859ece0>,
 <omni.isaac.core.materials.physics_material.PhysicsMaterial object at 0x7f720859ece0>,
 <omni.isaac.core.materials.physics_material.PhysicsMaterial object at 0x7f720859ece0>]
>>>
>>> # get the applied material for the first, middle and last of the 5 envs
>>> prims.get_applied_physics_materials(indices=np.array([0, 2, 4]))
[<omni.isaac.core.materials.physics_material.PhysicsMaterial object at 0x7f720859ece0>,
 <omni.isaac.core.materials.physics_material.PhysicsMaterial object at 0x7f720859ece0>,
 <omni.isaac.core.materials.physics_material.PhysicsMaterial object at 0x7f720859ece0>]
get_applied_visual_materials(indices: Optional[Union[numpy.ndarray, list, torch.Tensor, warp.types.array]] = None) List[omni.isaac.core.materials.visual_material.VisualMaterial]

Get the current applied visual materials

Parameters

indices (Optional[Union[np.ndarray, list, torch.Tensor, wp.array]], optional) – indices to specify which prims to query. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

Returns

a list of the current applied visual materials to the prims if its type is currently supported.

Return type

List[VisualMaterial]

Example:

>>> # get all applied visual materials. Returned size is 5 for the example: 5 envs
>>> prims.get_applied_visual_materials()
[<omni.isaac.core.materials.omni_glass.OmniGlass object at 0x7f829c165de0>,
 <omni.isaac.core.materials.omni_glass.OmniGlass object at 0x7f829c165de0>,
 <omni.isaac.core.materials.omni_glass.OmniGlass object at 0x7f829c165de0>,
 <omni.isaac.core.materials.omni_glass.OmniGlass object at 0x7f829c165de0>,
 <omni.isaac.core.materials.omni_glass.OmniGlass object at 0x7f829c165de0>]
>>>
>>> # get the applied visual materials for the first, middle and last of the 5 envs. Returned size is 3
>>> prims.get_applied_visual_materials(indices=np.array([0, 2, 4]))
[<omni.isaac.core.materials.omni_glass.OmniGlass object at 0x7f829c165de0>,
 <omni.isaac.core.materials.omni_glass.OmniGlass object at 0x7f829c165de0>,
 <omni.isaac.core.materials.omni_glass.OmniGlass object at 0x7f829c165de0>]
get_collision_approximations(indices: Optional[Union[numpy.ndarray, list, torch.Tensor, warp.types.array]] = None) List[str]

Get collision approximation types for prims in the view.

Approximation

Full name

Description

"none"

Triangle Mesh

The mesh geometry is used directly as a collider without any approximation

"convexDecomposition"

Convex Decomposition

A convex mesh decomposition is performed. This results in a set of convex mesh colliders

"convexHull"

Convex Hull

A convex hull of the mesh is generated and used as the collider

"boundingSphere"

Bounding Sphere

A bounding sphere is computed around the mesh and used as a collider

"boundingCube"

Bounding Cube

An optimally fitting box collider is computed around the mesh

"meshSimplification"

Mesh Simplification

A mesh simplification step is performed, resulting in a simplified triangle mesh collider

"sdf"

SDF Mesh

SDF (Signed-Distance-Field) use high-detail triangle meshes as collision shape

"sphereFill"

Sphere Approximation

A sphere mesh decomposition is performed. This results in a set of sphere colliders

Parameters

indices (Optional[Union[np.ndarray, list, torch.Tensor, wp.array]], optional) – indices to specify which prims to query. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

Returns

approximations used for collision. size == M or size of the view.

Return type

List[str]

Example:

>>> # get the collision approximation of all prims. Returned size is (5,).
>>> prims.get_collision_approximations()
['none', 'none', 'none', 'none', 'none']
>>>
>>> # get the collision approximation of the prims for the first, middle and last of the 5 envs
>>> prims.get_collision_approximations(indices=np.array([0, 2, 4]))
['none', 'none', 'none']
get_contact_force_data(indices: Optional[Union[numpy.ndarray, List, torch.Tensor, warp.types.array]] = None, clone: bool = True, dt: float = 1.0) Tuple[Union[numpy.ndarray, torch.Tensor, warp.types.indexedarray], Union[numpy.ndarray, torch.Tensor, warp.types.indexedarray], Union[numpy.ndarray, torch.Tensor, warp.types.indexedarray], Union[numpy.ndarray, torch.Tensor, warp.types.indexedarray], Union[numpy.ndarray, torch.Tensor, warp.types.indexedarray], Union[numpy.ndarray, torch.Tensor, warp.types.indexedarray]]

Get more detailed contact information between the prims in the view and the filter prims. Specifically, this method provides individual contact normals, contact points, contact separations as well as contact forces for each pair (the sum of which equals the forces that the get_contact_force_matrix method provides as the force aggregate of a pair) Given to the dynamic nature of collision between bodies, this method will provide buffers of contact data which are arranged sequentially for each pair. The starting index and the number of contact data points for each pair in this stream can be realized from pair_contacts_start_indices, and pair_contacts_count tensors. They both have a dimension of (self.num_shapes, self.num_filters) where filter_count is determined according to the filter_paths_expr parameter.

Parameters
  • indices (Optional[Union[np.ndarray, list, torch.Tensor, wp.array]], optional) – indices to specify which prims to query. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

  • clone (bool, optional) – True to return a clone of the internal buffer. Otherwise False. Defaults to True.

  • dt (float) – time step multiplier to convert the underlying impulses to forces. If the default value is used then the forces are in fact contact impulses

Returns

Tuple[Union[np.ndarray, torch.Tensor, wp.indexedarray], Union[np.ndarray, torch.Tensor, wp.indexedarray],

Union[np.ndarray, torch.Tensor, wp.indexedarray], Union[np.ndarray, torch.Tensor, wp.indexedarray], Union[np.ndarray, torch.Tensor, wp.indexedarray], Union[np.ndarray, torch.Tensor, wp.indexedarray]]: A set of buffers for normal forces with shape (max_contact_count, 1), points with shape (max_contact_count, 3), normals with shape (max_contact_count, 3), and distances with shape (max_contact_count, 1), as well as two tensors with shape (M, self.num_filters) to indicate the starting index and the number of contact data points per pair in the aforementioned buffers.

get_contact_force_matrix(indices: Optional[Union[numpy.ndarray, List, torch.Tensor, warp.types.array]] = None, clone: bool = True, dt: float = 1.0) Union[numpy.ndarray, torch.Tensor, warp.types.indexedarray]

If the object is initialized with filter_paths_expr list, this method returns the contact forces between the prims in the view and the filter prims. i.e., a matrix of dimension (self.count, self._contact_view.num_filters, 3) where num_filters is the determined according to the filter_paths_expr parameter.

Parameters
  • indices (Optional[Union[np.ndarray, list, torch.Tensor, wp.array]], optional) – indices to specify which prims to query. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

  • clone (bool, optional) – True to return a clone of the internal buffer. Otherwise False. Defaults to True.

  • dt (float) – time step multiplier to convert the underlying impulses to forces. If the default value is used then the forces are in fact contact impulses

Returns

Net contact forces of the prims with shape (M, self._contact_view.num_filters, 3).

Return type

Union[np.ndarray, torch.Tensor, wp.indexedarray]

get_contact_offsets(indices: Optional[Union[numpy.ndarray, list, torch.Tensor, warp.types.array]] = None) Union[numpy.ndarray, torch.Tensor, warp.types.indexedarray]

Get contact offsets for prims in the view.

Shapes whose distance is less than the sum of their contact offset values will generate contacts

Search for Advanced Collision Detection in PhysX docs for more details

Parameters

indices (Optional[Union[np.ndarray, list, torch.Tensor, wp.array]], optional) – indices to specify which prims to query. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

Returns

Contact offsets of the collision shapes. Shape is (M,).

Return type

Union[np.ndarray, torch.Tensor, wp.indexedarray]

Example:

>>> # get the contact offsets of all prims. Returned shape is (5,).
>>> prims.get_contact_offsets()
[-inf -inf -inf -inf -inf]
>>>
>>> # get the contact offsets of the prims for the first, middle and last of the 5 envs
>>> prims.get_contact_offsets(indices=np.array([0, 2, 4]))
[-inf -inf -inf]
get_default_state() omni.isaac.core.utils.types.XFormPrimViewState

Get the default states (positions and orientations) defined with the set_default_state method

Returns

returns the default state of the prims that is used after each reset.

Return type

XFormPrimViewState

Example:

>>> state = prims.get_default_state()
>>> state
<omni.isaac.core.utils.types.XFormPrimViewState object at 0x7f82f73e3070>
>>> state.positions
[[ 1.5  -0.75  0.  ]
 [ 1.5   0.75  0.  ]
 [ 0.   -0.75  0.  ]
 [ 0.    0.75  0.  ]
 [-1.5  -0.75  0.  ]]
>>> state.orientations
[[1. 0. 0. 0.]
 [1. 0. 0. 0.]
 [1. 0. 0. 0.]
 [1. 0. 0. 0.]
 [1. 0. 0. 0.]]
get_local_poses(indices: Optional[Union[numpy.ndarray, list, torch.Tensor, warp.types.array]] = None) Union[Tuple[numpy.ndarray, numpy.ndarray], Tuple[torch.Tensor, torch.Tensor], Tuple[warp.types.indexedarray, warp.types.indexedarray]]

Get prim poses in the view with respect to the local frame (the prim’s parent frame)

Parameters

indices (Optional[Union[np.ndarray, list, torch.Tensor, wp.array]], optional) – indices to specify which prims to query. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

Returns

first index is translations in the local frame of the prims. shape is (M, 3).

second index is quaternion orientations in the local frame of the prims. quaternion is scalar-first (w, x, y, z). shape is (M, 4).

Return type

Union[Tuple[np.ndarray, np.ndarray], Tuple[torch.Tensor, torch.Tensor], Tuple[wp.indexedarray, wp.indexedarray]]

Example:

>>> # get all prims poses with respect to the local frame.
>>> # Returned shape is position (5, 3) and orientation (5, 4) for the example: 5 envs
>>> positions, orientations = prims.get_local_poses()
>>> positions
[[ 1.5  -0.75  0.  ]
 [ 1.5   0.75  0.  ]
 [ 0.   -0.75  0.  ]
 [ 0.    0.75  0.  ]
 [-1.5  -0.75  0.  ]]
>>> orientations
[[1. 0. 0. 0.]
 [1. 0. 0. 0.]
 [1. 0. 0. 0.]
 [1. 0. 0. 0.]
 [1. 0. 0. 0.]]
>>>
>>> # get only the prims poses with respect to the local frame for the first, middle and last of the 5 envs.
>>> # Returned shape is position (3, 3) and orientation (3, 4) for the example: 3 envs selected
>>> positions, orientations = prims.get_local_poses(indices=np.array([0, 2, 4]))
>>> positions
[[ 1.5  -0.75  0.  ]
 [ 0.   -0.75  0.  ]
 [-1.5  -0.75  0.  ]]
>>> orientations
[[1. 0. 0. 0.]
 [1. 0. 0. 0.]
 [1. 0. 0. 0.]]
get_local_scales(indices: Optional[Union[numpy.ndarray, list, torch.Tensor, warp.types.array]] = None) Union[numpy.ndarray, torch.Tensor, warp.types.indexedarray]

Get prim scales in the view with respect to the local frame (the parent’s frame).

Parameters

indices (Optional[Union[np.ndarray, list, torch.Tensor, wp.array]], optional) – indices to specify which prims to query. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

Returns

scales applied to the prim’s dimensions in the local frame. shape is (M, 3).

Return type

Union[np.ndarray, torch.Tensor, wp.indexedarray]

Example:

>>> # get all prims scales with respect to the local frame.
>>> # Returned shape is (5, 3) for the example: 5 envs
>>> prims.get_local_scales()
[[1. 1. 1.]
 [1. 1. 1.]
 [1. 1. 1.]
 [1. 1. 1.]
 [1. 1. 1.]]
>>>
>>> # get only the prims scales with respect to the local frame for the first, middle and last of the 5 envs.
>>> # Returned shape is (3, 3) for the example: 3 envs selected
>>> prims.get_local_scales(indices=np.array([0, 2, 4]))
[[1. 1. 1.]
 [1. 1. 1.]
 [1. 1. 1.]]
get_min_torsional_patch_radii(indices: Optional[Union[numpy.ndarray, list, torch.Tensor]] = None) Union[numpy.ndarray, torch.Tensor]

Get minimum torsional patch radii for prims in the view.

Search for “Torsional Patch Radius” in PhysX docs for more details

Parameters

indices (Optional[Union[np.ndarray, list, torch.Tensor]], optional) – indices to specify which prims to query. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

Returns

minimum radius of the contact patch used to apply torsional friction. shape is (M,).

Return type

Union[np.ndarray, torch.Tensor]

Example:

>>> # get the minimum torsional patch radius of all prims. Returned shape is (5,).
>>> prims.get_min_torsional_patch_radii()
[0. 0. 0. 0. 0.]
>>>
>>> # get the minimum torsional patch radius of the prims for the first, middle and last of the 5 envs
>>> prims.get_min_torsional_patch_radii(indices=np.array([0, 2, 4]))
[0. 0. 0.]
get_net_contact_forces(indices: Optional[Union[numpy.ndarray, List, torch.Tensor, warp.types.array]] = None, clone: bool = True, dt: float = 1.0) Union[numpy.ndarray, torch.Tensor, warp.types.indexedarray]

If contact forces of the prims in the view are tracked, this method returns the net contact forces on prims. i.e., a matrix of dimension (self.count, 3)

Parameters
  • indices (Optional[Union[np.ndarray, list, torch.Tensor, wp.array]], optional) – indices to specify which prims to query. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

  • clone (bool, optional) – True to return a clone of the internal buffer. Otherwise False. Defaults to True.

  • dt (float) – time step multiplier to convert the underlying impulses to forces. If the default value is used then the forces are in fact contact impulses

Returns

Net contact forces of the prims with shape (M,3).

Return type

Union[np.ndarray, torch.Tensor, wp.indexedarray]

get_rest_offsets(indices: Optional[Union[numpy.ndarray, list, torch.Tensor, warp.types.array]] = None) Union[numpy.ndarray, torch.Tensor, warp.types.indexedarray]

Get rest offsets for prims in the view.

Two shapes will come to rest at a distance equal to the sum of their rest offset values. If the rest offset is 0, they should converge to touching exactly

Search for Advanced Collision Detection in PhysX docs for more details

Parameters

indices (Optional[Union[np.ndarray, list, torch.Tensor, wp.array]], optional) – indices to specify which prims to query. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

Returns

Rest offsets of the collision shapes. Shape is (M,).

Return type

Union[np.ndarray, torch.Tensor, wp.indexedarray]

Example:

>>> # get the rest offsets of all prims. Returned shape is (5,).
>>> prims.get_rest_offsets()
[-inf -inf -inf -inf -inf]
>>>
>>> # get the rest offsets of the prims for the first, middle and last of the 5 envs
>>> prims.get_rest_offsets(indices=np.array([0, 2, 4]))
[-inf -inf -inf]
get_torsional_patch_radii(indices: Optional[Union[numpy.ndarray, list, torch.Tensor, warp.types.array]] = None) Union[numpy.ndarray, torch.Tensor, warp.types.indexedarray]

Get torsional patch radii for prims in the view.

Search for “Torsional Patch Radius” in PhysX docs for more details

Parameters

indices (Optional[Union[np.ndarray, list, torch.Tensor, wp.array]], optional) – indices to specify which prims to query. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

Returns

radius of the contact patch used to apply torsional friction. shape is (M,).

Return type

Union[np.ndarray, torch.Tensor, wp.indexedarray]

Example:

>>> # get the torsional patch radius of all prims. Returned shape is (5,).
>>> prims.get_torsional_patch_radii()
[0. 0. 0. 0. 0.]
>>>
>>> # get the torsional patch radius of the prims for the first, middle and last of the 5 envs
>>> prims.get_torsional_patch_radii(indices=np.array([0, 2, 4]))
[0. 0. 0.]
get_visibilities(indices: Optional[Union[numpy.ndarray, list, torch.Tensor, warp.types.array]] = None) Union[numpy.ndarray, torch.Tensor, warp.types.indexedarray]

Returns the current visibilities of the prims in stage.

Parameters

indices (Optional[Union[np.ndarray, list, torch.Tensor, wp.array]], optional) – indices to specify which prims to query. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

Returns

Shape (M,) with type bool, where each item holds True

if the prim is visible in stage. False otherwise.

Return type

Union[np.ndarray, torch.Tensor, wp.indexedarray]

Example:

>>> # get all visibilities. Returned shape is (5,) for the example: 5 envs
>>> prims.get_visibilities()
[ True  True  True  True  True]
>>>
>>> # get the visibilities for the first, middle and last of the 5 envs. Returned shape is (3,)
>>> prims.get_visibilities(indices=np.array([0, 2, 4]))
[ True  True  True]
get_world_poses(indices: Optional[Union[numpy.ndarray, list, torch.Tensor, warp.types.array]] = None) Union[Tuple[numpy.ndarray, numpy.ndarray], Tuple[torch.Tensor, torch.Tensor], Tuple[warp.types.indexedarray, warp.types.indexedarray]]

Get the poses of the prims in the view with respect to the world’s frame

Parameters

indices (Optional[Union[np.ndarray, list, torch.Tensor, wp.array]], optional) – indices to specify which prims to query. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

Returns

first index is positions in the world frame of the prims. shape is (M, 3).

second index is quaternion orientations in the world frame of the prims. quaternion is scalar-first (w, x, y, z). shape is (M, 4).

Return type

Union[Tuple[np.ndarray, np.ndarray], Tuple[torch.Tensor, torch.Tensor], Tuple[wp.indexedarray, wp.indexedarray]]

Example:

>>> # get all prims poses with respect to the world's frame.
>>> # Returned shape is position (5, 3) and orientation (5, 4) for the example: 5 envs
>>> positions, orientations = prims.get_world_poses()
>>> positions
[[ 1.5  -0.75  0.  ]
 [ 1.5   0.75  0.  ]
 [ 0.   -0.75  0.  ]
 [ 0.    0.75  0.  ]
 [-1.5  -0.75  0.  ]]
>>> orientations
[[1. 0. 0. 0.]
 [1. 0. 0. 0.]
 [1. 0. 0. 0.]
 [1. 0. 0. 0.]
 [1. 0. 0. 0.]]
>>>
>>> # get only the prims poses with respect to the world's frame for the first, middle and last of the 5 envs.
>>> # Returned shape is position (3, 3) and orientation (3, 4) for the example: 3 envs selected
>>> positions, orientations = prims.get_world_poses(indices=np.array([0, 2, 4]))
>>> positions
[[ 1.5  -0.75  0.  ]
 [ 0.   -0.75  0.  ]
 [-1.5  -0.75  0.  ]]
>>> orientations
[[1. 0. 0. 0.]
 [1. 0. 0. 0.]
 [1. 0. 0. 0.]]
get_world_scales(indices: Optional[Union[numpy.ndarray, list, torch.Tensor, warp.types.array]] = None) Union[numpy.ndarray, torch.Tensor, warp.types.indexedarray]

Get prim scales in the view with respect to the world’s frame

Parameters

indices (Optional[Union[np.ndarray, list, torch.Tensor, wp.array]], optional) – indices to specify which prims to query. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

Returns

scales applied to the prim’s dimensions in the world frame. shape is (M, 3).

Return type

Union[np.ndarray, torch.Tensor, wp.indexedarray]

Example:

>>> # get all prims scales with respect to the world's frame.
>>> # Returned shape is (5, 3) for the example: 5 envs
>>> prims.get_world_scales()
[[1. 1. 1.]
 [1. 1. 1.]
 [1. 1. 1.]
 [1. 1. 1.]
 [1. 1. 1.]]
>>>
>>> # get only the prims scales with respect to the world's frame for the first, middle and last of the 5 envs.
>>> # Returned shape is (3, 3) for the example: 3 envs selected
>>> prims.get_world_scales(indices=np.array([0, 2, 4]))
[[1. 1. 1.]
 [1. 1. 1.]
 [1. 1. 1.]]
initialize(physics_sim_view: Optional[omni.physics.tensors.bindings._physicsTensors.SimulationView] = None) None

Create a physics simulation view if not passed and set other properties using the PhysX tensor API

Note

If the rigid prim view has been added to the world scene (e.g., world.scene.add(prims)), it will be automatically initialized when the world is reset (e.g., world.reset()).

Warning

This method needs to be called after each hard reset (e.g., Stop + Play on the timeline) before interacting with any other class method.

Parameters

physics_sim_view (omni.physics.tensors.SimulationView, optional) – current physics simulation view. Defaults to None.

Example:

>>> prims.initialize()
is_collision_enabled(indices: Optional[Union[numpy.ndarray, list, torch.Tensor, warp.types.array]] = None) Union[numpy.ndarray, torch.Tensor, warp.types.indexedarray]

Queries if collision is enabled on prims in the view.

Parameters

indices (Optional[Union[np.ndarray, list, torch.Tensor, wp.array]], optional) – indices to specify which prims to query. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

Returns

True if collision is enabled. Shape is (M,).

Return type

Union[np.ndarray, torch.Tensor, wp.indexedarray]

Example:

>>> # check if the collision is enabled for all prims. Returned size is (5,).
>>> prims.is_collision_enabled()
[ True  True  True  True  True]
>>>
>>> # check if the collision is enabled for the first, middle and last of the 5 envs
>>> prims.is_collision_enabled(indices=np.array([0, 2, 4]))
[ True  True  True]

Returns: bool: True if the prim corresponds to a non root link in an articulation. Otherwise False.

is_valid(indices: Optional[Union[numpy.ndarray, list, torch.Tensor, warp.types.array]] = None) bool

Check that all prims have a valid USD Prim

Parameters

indices (Optional[Union[np.ndarray, list, torch.Tensor, wp.array]], optional) – indices to specify which prims to query. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

Returns

True if all prim paths specified in the view correspond to a valid prim in stage. False otherwise.

Return type

bool

Example:

>>> prims.is_valid()
True
is_visual_material_applied(indices: Optional[Union[numpy.ndarray, list, torch.Tensor, warp.types.array]] = None) List[bool]

Check if there is a visual material applied

Parameters

indices (Optional[Union[np.ndarray, list, torch.Tensor, wp.array]], optional) – indices to specify which prims to query. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

Returns

True if there is a visual material applied is applied to the corresponding prim in the view. False otherwise.

Return type

List[bool]

Example:

>>> # given a visual material that is applied only to the first and the last environment
>>> prims.is_visual_material_applied()
[True, False, False, False, True]
>>>
>>> # check for the first, middle and last of the 5 envs
>>> prims.is_visual_material_applied(indices=np.array([0, 2, 4]))
[True, False, True]
property name: str

Returns: str: name given to the prims view when instantiating it.

post_reset() None

Reset the prims to its default state (positions and orientations)

Example:

>>> prims.post_reset()
property prim_paths: List[str]
Returns

list of prim paths in the stage encapsulated in this view.

Return type

List[str]

Example:

>>> prims.prim_paths
['/World/envs/env_0', '/World/envs/env_1', '/World/envs/env_2', '/World/envs/env_3', '/World/envs/env_4']
property prims: List[pxr.Usd.Prim]
Returns

List of USD Prim objects encapsulated in this view.

Return type

List[Usd.Prim]

Example:

>>> prims.prims
[Usd.Prim(</World/envs/env_0>), Usd.Prim(</World/envs/env_1>), Usd.Prim(</World/envs/env_2>),
 Usd.Prim(</World/envs/env_3>), Usd.Prim(</World/envs/env_4>)]
set_collision_approximations(approximation_types: List[str], indices: Optional[Union[numpy.ndarray, list, torch.Tensor, warp.types.array]] = None) None

Set collision approximation types for prims in the view.

Approximation

Full name

Description

"none"

Triangle Mesh

The mesh geometry is used directly as a collider without any approximation

"convexDecomposition"

Convex Decomposition

A convex mesh decomposition is performed. This results in a set of convex mesh colliders

"convexHull"

Convex Hull

A convex hull of the mesh is generated and used as the collider

"boundingSphere"

Bounding Sphere

A bounding sphere is computed around the mesh and used as a collider

"boundingCube"

Bounding Cube

An optimally fitting box collider is computed around the mesh

"meshSimplification"

Mesh Simplification

A mesh simplification step is performed, resulting in a simplified triangle mesh collider

"sdf"

SDF Mesh

SDF (Signed-Distance-Field) use high-detail triangle meshes as collision shape

"sphereFill"

Sphere Approximation

A sphere mesh decomposition is performed. This results in a set of sphere colliders

Parameters
  • approximation_types (List[str]) – approximations used for collision. List size == M or the size of the view.

  • indices (Optional[Union[np.ndarray, list, torch.Tensor, wp.array]], optional) – indices to specify which prims to manipulate. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

Example:

>>> # set the collision approximations for all the prims to the specified values.
>>> prims.set_collision_approximations(["convexDecomposition"] * num_envs)
>>>
>>> # set the collision approximations for the first, middle and last of the 5 envs
>>> types = ["convexDecomposition", "convexHull", "meshSimplification"]
>>> prims.set_collision_approximations(types, indices=np.array([0, 2, 4]))
set_contact_offsets(offsets: Union[numpy.ndarray, torch.Tensor, warp.types.array], indices: Optional[Union[numpy.ndarray, list, torch.Tensor, warp.types.array]] = None) None

Set contact offsets for prims in the view.

Shapes whose distance is less than the sum of their contact offset values will generate contacts

Search for Advanced Collision Detection in PhysX docs for more details

Parameters
  • offsets (Union[np.ndarray, torch.Tensor, wp.array]) – Contact offsets of the collision shapes. Allowed range [maximum(0, rest_offset), 0]. Default value is -inf, means default is picked by simulation based on the shape extent. Shape (M,).

  • indices (Optional[Union[np.ndarray, list, torch.Tensor, wp.array]], optional) – indices to specify which prims to manipulate. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

Example:

>>> # set the contact offset for all the prims to the specified values.
>>> prims.set_contact_offsets(np.full(num_envs, 0.02))
>>>
>>> # set the contact offset for the first, middle and last of the 5 envs
>>> prims.set_contact_offsets(np.full(3, 0.02), indices=np.array([0, 2, 4]))
set_default_state(positions: Optional[Union[numpy.ndarray, torch.Tensor, warp.types.array]] = None, orientations: Optional[Union[numpy.ndarray, torch.Tensor, warp.types.array]] = None, indices: Optional[Union[numpy.ndarray, list, torch.Tensor, warp.types.array]] = None) None

Set the default state of the prims (positions and orientations), that will be used after each reset.

Note

The default states will be set during post-reset (e.g., calling .post_reset() or world.reset() methods)

Parameters
  • positions (Optional[Union[np.ndarray, torch.Tensor, wp.array]], optional) – positions in the world frame of the prim. shape is (M, 3). Defaults to None, which means left unchanged.

  • orientations (Optional[Union[np.ndarray, torch.Tensor, wp.array]], optional) – quaternion orientations in the world frame of the prim. quaternion is scalar-first (w, x, y, z). shape is (M, 4). Defaults to None, which means left unchanged.

  • indices (Optional[Union[np.ndarray, list, torch.Tensor, wp.array]], optional) – indices to specify which prims to manipulate. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

Example:

>>> # configure default states for all prims
>>> positions = np.zeros((num_envs, 3))
>>> positions[:, 0] = np.arange(num_envs)
>>> orientations = np.tile(np.array([1.0, 0.0, 0.0, 0.0]), (num_envs, 1))
>>> prims.set_default_state(positions=positions, orientations=orientations)
>>>
>>> # set default states during post-reset
>>> prims.post_reset()
set_local_poses(translations: Optional[Union[numpy.ndarray, torch.Tensor, warp.types.array]] = None, orientations: Optional[Union[numpy.ndarray, torch.Tensor, warp.types.array]] = None, indices: Optional[Union[numpy.ndarray, list, torch.Tensor, warp.types.array]] = None) None

Set prim poses in the view with respect to the local frame (the prim’s parent frame)

Warning

This method will change (teleport) the prim poses immediately to the indicated value

Parameters
  • translations (Optional[Union[np.ndarray, torch.Tensor, wp.array]], optional) – translations in the local frame of the prims (with respect to its parent prim). shape is (M, 3). Defaults to None, which means left unchanged.

  • orientations (Optional[Union[np.ndarray, torch.Tensor, wp.array]], optional) – quaternion orientations in the local frame of the prims. quaternion is scalar-first (w, x, y, z). shape is (M, 4). Defaults to None, which means left unchanged.

  • indices (Optional[Union[np.ndarray, list, torch.Tensor, wp.array]], optional) – indices to specify which prims to manipulate. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

Hint

This method belongs to the methods used to set the prim state

Example:

>>> # reposition all prims
>>> positions = np.zeros((num_envs, 3))
>>> positions[:,0] = np.arange(num_envs)
>>> orientations = np.tile(np.array([1.0, 0.0, 0.0, 0.0]), (num_envs, 1))
>>> prims.set_local_poses(positions, orientations)
>>>
>>> # reposition only the prims for the first, middle and last of the 5 envs
>>> positions = np.zeros((3, 3))
>>> positions[:,1] = np.arange(3)
>>> orientations = np.tile(np.array([1.0, 0.0, 0.0, 0.0]), (3, 1))
>>> prims.set_local_poses(positions, orientations, indices=np.array([0, 2, 4]))
set_local_scales(scales: Optional[Union[numpy.ndarray, torch.Tensor, warp.types.array]], indices: Optional[Union[numpy.ndarray, list, torch.Tensor, warp.types.array]] = None) None

Set prim scales in the view with respect to the local frame (the prim’s parent frame)

Parameters
  • scales (Optional[Union[np.ndarray, torch.Tensor, wp.array]]) – scales to be applied to the prim’s dimensions in the view. shape is (M, 3).

  • indices (Optional[Union[np.ndarray, list, torch.Tensor, wp.array]], optional) – indices to specify which prims to manipulate. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

Example:

>>> # set the scale for all prims. Since there are 5 envs, the scale is repeated 5 times
>>> scales = np.tile(np.array([1.0, 0.75, 0.5]), (num_envs, 1))
>>> prims.set_local_scales(scales)
>>>
>>> # set the scale for the first, middle and last of the 5 envs
>>> scales = np.tile(np.array([1.0, 0.75, 0.5]), (3, 1))
>>> prims.set_local_scales(scales, indices=np.array([0, 2, 4]))
set_min_torsional_patch_radii(radii: Union[numpy.ndarray, torch.Tensor, warp.types.array], indices: Optional[Union[numpy.ndarray, list, torch.Tensor, warp.types.array]] = None) None

Set minimum torsional patch radii for prims in the view.

Search for “Torsional Patch Radius” in PhysX docs for more details

Parameters
  • radii (Union[np.ndarray, torch.Tensor, wp.array]) – minimum radius of the contact patch used to apply torsional friction. Allowed range [0, max_float]. shape is (M, ).

  • indices (Optional[Union[np.ndarray, list, torch.Tensor, wp.array]], optional) – indices to specify which prims to manipulate. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

Example:

>>> # set the minimum torsional patch radius for all the prims to the specified values.
>>> prims.set_min_torsional_patch_radii(np.full(num_envs, 0.05))
>>>
>>> # set the minimum torsional patch radius for the first, middle and last of the 5 envs
>>> prims.set_min_torsional_patch_radii(np.full(3, 0.05), indices=np.array([0, 2, 4]))
set_rest_offsets(offsets: Union[numpy.ndarray, torch.Tensor, warp.types.array], indices: Optional[Union[numpy.ndarray, list, torch.Tensor, warp.types.array]] = None) None

Set rest offsets for prims in the view.

Two shapes will come to rest at a distance equal to the sum of their rest offset values. If the rest offset is 0, they should converge to touching exactly

Search for Advanced Collision Detection in PhysX docs for more details

Warning

The contact offset must be positive and greater than the rest offset

Parameters
  • offsets (Union[np.ndarray, torch.Tensor, wp.array]) – Rest offset of a collision shape. Allowed range [-max_float, contact_offset]. Default value is -inf, means default is picked by simulation. For rigid bodies its zero. Shape (M,).

  • indices (Optional[Union[np.ndarray, list, torch.Tensor, wp.array]], optional) – indices to specify which prims to manipulate. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

Example:

>>> # set the rest offset for all the prims to the specified values.
>>> prims.set_rest_offsets(np.full(num_envs, 0.01))
>>>
>>> # set the rest offset for the first, middle and last of the 5 envs
>>> prims.set_rest_offsets(np.full(3, 0.01), indices=np.array([0, 2, 4]))
set_torsional_patch_radii(radii: Union[numpy.ndarray, torch.Tensor, warp.types.array], indices: Optional[Union[numpy.ndarray, list, torch.Tensor, warp.types.array]] = None) None

Set torsional patch radii for prims in the view.

Search for “Torsional Patch Radius” in PhysX docs for more details

Parameters
  • radii (Union[np.ndarray, torch.Tensor, wp.array]) – radius of the contact patch used to apply torsional friction. Allowed range [0, max_float]. shape is (M,).

  • indices (Optional[Union[np.ndarray, list, torch.Tensor, wp.array]], optional) – indices to specify which prims to manipulate. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

Example:

>>> # set the torsional patch radius for all the prims to the specified values.
>>> prims.set_torsional_patch_radii(np.full(num_envs, 0.1))
>>>
>>> # set the torsional patch radius for the first, middle and last of the 5 envs
>>> prims.set_torsional_patch_radii(np.full(3, 0.1), indices=np.array([0, 2, 4]))
set_visibilities(visibilities: Union[numpy.ndarray, torch.Tensor, warp.types.array], indices: Optional[Union[numpy.ndarray, list, torch.Tensor, warp.types.array]] = None) None

Set the visibilities of the prims in stage

Parameters
  • visibilities (Union[np.ndarray, torch.Tensor, wp.array]) – flag to set the visibilities of the usd prims in stage. Shape (M,). Where M <= size of the encapsulated prims in the view.

  • indices (Optional[Union[np.ndarray, list, torch.Tensor, wp.array]], optional) – indices to specify which prims to manipulate. Shape (M,). Defaults to None (i.e: all prims in the view).

Example:

>>> # make all prims not visible in the stage
>>> prims.set_visibilities(visibilities=[False] * num_envs)
set_world_poses(positions: Optional[Union[numpy.ndarray, torch.Tensor, warp.types.array]] = None, orientations: Optional[Union[numpy.ndarray, torch.Tensor, warp.types.array]] = None, indices: Optional[Union[numpy.ndarray, list, torch.Tensor, warp.types.array]] = None) None

Set prim poses in the view with respect to the world’s frame

Warning

This method will change (teleport) the prim poses immediately to the indicated value

Parameters
  • positions (Optional[Union[np.ndarray, torch.Tensor, wp.array]], optional) – positions in the world frame of the prims. shape is (M, 3). Defaults to None, which means left unchanged.

  • orientations (Optional[Union[np.ndarray, torch.Tensor, wp.array]], optional) – quaternion orientations in the world frame of the prims. quaternion is scalar-first (w, x, y, z). shape is (M, 4). Defaults to None, which means left unchanged.

  • indices (Optional[Union[np.ndarray, list, torch.Tensor, wp.array]], optional) – indices to specify which prims to query. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

Hint

This method belongs to the methods used to set the prim state

Example:

>>> # reposition all prims in row (x-axis)
>>> positions = np.zeros((num_envs, 3))
>>> positions[:,0] = np.arange(num_envs)
>>> orientations = np.tile(np.array([1.0, 0.0, 0.0, 0.0]), (num_envs, 1))
>>> prims.set_world_poses(positions, orientations)
>>>
>>> # reposition only the prims for the first, middle and last of the 5 envs in column (y-axis)
>>> positions = np.zeros((3, 3))
>>> positions[:,1] = np.arange(3)
>>> orientations = np.tile(np.array([1.0, 0.0, 0.0, 0.0]), (3, 1))
>>> prims.set_world_poses(positions, orientations, indices=np.array([0, 2, 4]))

Rigid Prim

class RigidPrim(prim_path: str, name: str = 'rigid_prim', position: Optional[Sequence[float]] = None, translation: Optional[Sequence[float]] = None, orientation: Optional[Sequence[float]] = None, scale: Optional[Sequence[float]] = None, visible: Optional[bool] = None, mass: Optional[float] = None, density: Optional[float] = None, linear_velocity: Optional[numpy.ndarray] = None, angular_velocity: Optional[numpy.ndarray] = None)

High level wrapper to deal with a rigid body prim (only one rigid body prim) and its attributes/properties.

Warning

The rigid body object must be initialized in order to be able to operate on it. See the initialize method for more details.

Note

If the prim does not already have the Rigid Body API applied to it before init, it will apply it.

Parameters
  • prim_path (str) – prim path of the Prim to encapsulate or create.

  • name (str, optional) – shortname to be used as a key by Scene class. Note: needs to be unique if the object is added to the Scene. Defaults to “rigid_prim”.

  • position (Optional[Sequence[float]], optional) – position in the world frame of the prim. shape is (3, ). Defaults to None, which means left unchanged.

  • translation (Optional[Sequence[float]], optional) – translation in the local frame of the prim (with respect to its parent prim). shape is (3, ). Defaults to None, which means left unchanged.

  • orientation (Optional[Sequence[float]], optional) – quaternion orientation in the world/ local frame of the prim (depends if translation or position is specified). quaternion is scalar-first (w, x, y, z). shape is (4, ). Defaults to None, which means left unchanged.

  • scale (Optional[Sequence[float]], optional) – local scale to be applied to the prim’s dimensions. shape is (3, ). Defaults to None, which means left unchanged.

  • visible (bool, optional) – set to false for an invisible prim in the stage while rendering. Defaults to True.

  • mass (Optional[float], optional) – mass in kg. Defaults to None.

  • density (Optional[float], optional) – density. Defaults to None.

  • linear_velocity (Optional[np.ndarray], optional) – linear velocity in the world frame. Defaults to None.

  • angular_velocity (Optional[np.ndarray], optional) – angular velocity in the world frame. Defaults to None.

Example:

>>> import omni.isaac.core.utils.stage as stage_utils
>>> from omni.isaac.core.prims import RigidPrim
>>>
>>> # create a Cube at the given path
>>> stage_utils.get_current_stage().DefinePrim("/World/Xform", "Xform")
>>> stage_utils.get_current_stage().DefinePrim("/World/Xform/Cube", "Cube")
>>>
>>> # wrap the prim as rigid prim
>>> prim = RigidPrim("/World/Xform")
>>> prim
<omni.isaac.core.prims.rigid_prim.RigidPrim object at 0x7fc4a7f56e90>
apply_visual_material(visual_material: omni.isaac.core.materials.visual_material.VisualMaterial, weaker_than_descendants: bool = False) None

Apply visual material to the held prim and optionally its descendants.

Parameters
  • visual_material (VisualMaterial) – visual material to be applied to the held prim. Currently supports PreviewSurface, OmniPBR and OmniGlass.

  • weaker_than_descendants (bool, optional) – True if the material shouldn’t override the descendants materials, otherwise False. Defaults to False.

Example:

>>> from omni.isaac.core.materials import OmniGlass
>>>
>>> # create a dark-red glass visual material
>>> material = OmniGlass(
...     prim_path="/World/material/glass",  # path to the material prim to create
...     ior=1.25,
...     depth=0.001,
...     thin_walled=False,
...     color=np.array([0.5, 0.0, 0.0])
... )
>>> prim.apply_visual_material(material)
disable_rigid_body_physics() None

Disable the rigid body physics

When disabled, the object will not be moved by external forces such as gravity and collisions

Example:

>>> prim.disable_rigid_body_physics()
enable_rigid_body_physics() None

Enable the rigid body physics

When enabled, the object will be moved by external forces such as gravity and collisions

Example:

>>> prim.enable_rigid_body_physics()
get_angular_velocity()

Get the angular velocity of the rigid body

Returns

current angular velocity of the the rigid prim. Shape (3,).

Return type

np.ndarray

Example:

>>> prim.get_angular_velocity()]
[-0.01727393  0.00827609 -0.00040014]
get_applied_visual_material() omni.isaac.core.materials.visual_material.VisualMaterial

Return the current applied visual material in case it was applied using apply_visual_material or it’s one of the following materials that was already applied before: PreviewSurface, OmniPBR and OmniGlass.

Returns

the current applied visual material if its type is currently supported.

Return type

VisualMaterial

Example:

>>> # given a visual material applied
>>> prim.get_applied_visual_material()
<omni.isaac.core.materials.omni_glass.OmniGlass object at 0x7f36263106a0>
get_current_dynamic_state() omni.isaac.core.utils.types.DynamicState

Get the current rigid body state (position, orientation and linear and angular velocities)

Returns

the dynamic state of the rigid body prim

Return type

DynamicState

Example:

>>> # for the example the rigid body is in free fall
>>> state = prim.get_current_dynamic_state()
>>> state
<omni.isaac.core.utils.types.DynamicState object at 0x7f740b36f670>
>>> state.position
[  0.99999857   2.0000017  -74.2862    ]
>>> state.orientation
[ 1.0000000e+00 -2.3961178e-07 -4.9891562e-09  4.9388258e-09]
>>> state.linear_velocity
[  0.        0.      -38.09554]
>>> state.angular_velocity
[0. 0. 0.]
get_default_state() omni.isaac.core.utils.types.DynamicState

Get the default rigid body state (position, orientation and linear and angular velocities)

Returns

returns the default state of the prim that is used after each reset

Return type

DynamicState

Example:

>>> state = prim.get_default_state()
>>> state
<omni.isaac.core.utils.types.DynamicState object at 0x7f7411fcbe20>
>>> state.position
[-7.8622378e-07  1.4450421e-06  1.6135601e-07]
>>> state.orientation
[ 9.9999994e-01 -2.7194994e-07  2.9607077e-07  2.7016510e-08]
>>> state.linear_velocity
[0. 0. 0.]
>>> state.angular_velocity
[0. 0. 0.]
get_density() float

Get the density of the rigid body

Returns

density of the rigid body.

Return type

float

Example:

>>> prim.get_density()
0
get_linear_velocity() numpy.ndarray

Get the linear velocity of the rigid body

Returns

current linear velocity of the the rigid prim. Shape (3,).

Return type

np.ndarray

Example:

>>> prim.get_linear_velocity()
[ 1.0812164e-04  6.1415871e-05 -2.1341663e-04]
get_local_pose() Tuple[numpy.ndarray, numpy.ndarray]

Get prim’s pose with respect to the local frame (the prim’s parent frame)

Returns

first index is the position in the local frame (with shape (3, )). Second index is quaternion orientation (with shape (4, )) in the local frame

Return type

Tuple[np.ndarray, np.ndarray]

Example:

>>> # if the prim is in position (1.0, 0.5, 0.0) with respect to the world frame
>>> position, orientation = prim.get_local_pose()
>>> position
[0. 0. 0.]
>>> orientation
[0. 0. 0.]
get_local_scale() numpy.ndarray

Get prim’s scale with respect to the local frame (the parent’s frame)

Returns

scale applied to the prim’s dimensions in the local frame. shape is (3, ).

Return type

np.ndarray

Example:

>>> prim.get_local_scale()
[1. 1. 1.]
get_mass() float

Get the mass of the rigid body

Returns

mass of the rigid body in kg.

Return type

float

Example:

>>> prim.get_mass()
0
get_sleep_threshold() float

Get the threshold for the rigid body to enter a sleep state

Search for Rigid Body Dynamics > Sleeping in PhysX docs for more details

Returns

Mass-normalized kinetic energy threshold below which

an actor may go to sleep. Range: [0, inf) Defaults: 0.00005 * tolerancesSpeed* tolerancesSpeed Units: distance^2 / second^2.

Return type

float

Example:

>>> prim.get_sleep_threshold()
5e-05
get_visibility() bool
Returns

true if the prim is visible in stage. false otherwise.

Return type

bool

Example:

>>> # get the visible state of an visible prim on the stage
>>> prim.get_visibility()
True
get_world_pose() Tuple[numpy.ndarray, numpy.ndarray]

Get prim’s pose with respect to the world’s frame

Returns

first index is the position in the world frame (with shape (3, )). Second index is quaternion orientation (with shape (4, )) in the world frame

Return type

Tuple[np.ndarray, np.ndarray]

Example:

>>> # if the prim is in position (1.0, 0.5, 0.0) with respect to the world frame
>>> position, orientation = prim.get_world_pose()
>>> position
[1.  0.5 0. ]
>>> orientation
[1. 0. 0. 0.]
get_world_scale() numpy.ndarray

Get prim’s scale with respect to the world’s frame

Returns

scale applied to the prim’s dimensions in the world frame. shape is (3, ).

Return type

np.ndarray

Example:

>>> prim.get_world_scale()
[1. 1. 1.]
initialize(physics_sim_view=None) None

Create a physics simulation view if not passed and using PhysX tensor API

Note

If the prim has been added to the world scene (e.g., world.scene.add(prim)), it will be automatically initialized when the world is reset (e.g., world.reset()).

Parameters

physics_sim_view (omni.physics.tensors.SimulationView, optional) – current physics simulation view. Defaults to None.

Example:

>>> prim.initialize()
is_valid() bool

Check if the prim path has a valid USD Prim at it

Returns

True is the current prim path corresponds to a valid prim in stage. False otherwise.

Return type

bool

Example:

>>> # given an existing and valid prim
>>> prims.is_valid()
True
is_visual_material_applied() bool

Check if there is a visual material applied

Returns

True if there is a visual material applied. False otherwise.

Return type

bool

Example:

>>> # given a visual material applied
>>> prim.is_visual_material_applied()
True
property name: Optional[str]

Returns: str: name given to the prim when instantiating it. Otherwise None.

Used to query if the prim is a non root articulation link

Returns

True if the prim itself is a non root link

Return type

bool

Example:

>>> # for a wrapped articulation (where the root prim has the Physics Articulation Root property applied)
>>> prim.non_root_articulation_link
False
post_reset() None

Reset the prim to its default state (position and orientation).

Note

For an articulation, in addition to configuring the root prim’s default position and spatial orientation (defined via the set_default_state method), the joint’s positions, velocities, and efforts (defined via the set_joints_default_state method) are imposed

Example:

>>> prim.post_reset()
property prim: pxr.Usd.Prim

Returns: Usd.Prim: USD Prim object that this object holds.

property prim_path: str

Returns: str: prim path in the stage

set_angular_velocity(velocity: numpy.ndarray) None

Set the angular velocity of the rigid body in stage

Warning

This method will immediately set the articulation state

Parameters

velocity (np.ndarray) – angular velocity to set the rigid prim to. Shape (3,).

Hint

This method belongs to the methods used to set the rigid prim kinematic state:

set_linear_velocity, set_angular_velocity

Example:

>>> prim.set_angular_velocity(np.array([0.0, 0.0, 10.0]))
set_default_state(position: Optional[Sequence[float]] = None, orientation: Optional[Sequence[float]] = None, linear_velocity: Optional[numpy.ndarray] = None, angular_velocity: Optional[numpy.ndarray] = None) None

Set the default state of the prim (position, orientation and linear and angular velocities), that will be used after each reset

Note

The default states will be set during post-reset (e.g., calling .post_reset() or world.reset() methods)

Parameters
  • position (Optional[Sequence[float]], optional) – position in the world frame of the prim. shape is (3, ). Defaults to None, which means left unchanged.

  • orientation (Optional[Sequence[float]], optional) – quaternion orientation in the world frame of the prim. quaternion is scalar-first (w, x, y, z). shape is (4, ). Defaults to None, which means left unchanged.

  • linear_velocity (np.ndarray) – linear velocity to set the rigid prim to. Shape (3,).

  • angular_velocity (np.ndarray) – angular velocity to set the rigid prim to. Shape (3,).

Example:

>>> prim.set_default_state(
...     position=np.array([1.0, 2.0, 3.0]),
...     orientation=np.array([1.0, 0.0, 0.0, 0.0]),
...     linear_velocity=np.array([0.0, 0.0, 0.0]),
...     angular_velocity=np.array([0.0, 0.0, 0.0])
... )
>>>
>>> prim.post_reset()
set_density(density: float) None

Set the density of the rigid body

Parameters

mass (float) – density of the rigid body.

Example:

>>> prim.set_density(0.9)
set_linear_velocity(velocity: numpy.ndarray)

Set the linear velocity of the rigid body in stage

Warning

This method will immediately set the rigid prim state

Parameters

velocity (np.ndarray) – linear velocity to set the rigid prim to. Shape (3,).

Hint

This method belongs to the methods used to set the rigid prim kinematic state:

set_linear_velocity, set_angular_velocity

Example:

>>> prim.set_linear_velocity(np.array([5.0, 0.0, 0.0]))
set_local_pose(translation: Optional[Sequence[float]] = None, orientation: Optional[Sequence[float]] = None) None

Set prim’s pose with respect to the local frame (the prim’s parent frame).

Warning

This method will change (teleport) the prim pose immediately to the indicated value

Parameters
  • translation (Optional[Sequence[float]], optional) – translation in the local frame of the prim (with respect to its parent prim). shape is (3, ). Defaults to None, which means left unchanged.

  • orientation (Optional[Sequence[float]], optional) – quaternion orientation in the local frame of the prim. quaternion is scalar-first (w, x, y, z). shape is (4, ). Defaults to None, which means left unchanged.

Hint

This method belongs to the methods used to set the prim state

Example:

>>> prim.set_local_pose(translation=np.array([1.0, 0.5, 0.0]), orientation=np.array([1., 0., 0., 0.]))
set_local_scale(scale: Optional[Sequence[float]]) None

Set prim’s scale with respect to the local frame (the prim’s parent frame).

Parameters

scale (Optional[Sequence[float]]) – scale to be applied to the prim’s dimensions. shape is (3, ). Defaults to None, which means left unchanged.

Example:

>>> # scale prim 10 times smaller
>>> prim.set_local_scale(np.array([0.1, 0.1, 0.1]))
set_mass(mass: float) None

Set the mass of the rigid body

Parameters

mass (float) – mass of the rigid body in kg.

Example:

>>> prim.set_mass(1.0)
set_sleep_threshold(threshold: float) None

Set the threshold for the rigid body to enter a sleep state

Search for Rigid Body Dynamics > Sleeping in PhysX docs for more details

Parameters

threshold (float) – Mass-normalized kinetic energy threshold below which an actor may go to sleep. Range: [0, inf) Defaults: 0.00005 * tolerancesSpeed* tolerancesSpeed Units: distance^2 / second^2.

Example:

>>> prim.set_sleep_threshold(1e-5)
set_visibility(visible: bool) None

Set the visibility of the prim in stage

Parameters

visible (bool) – flag to set the visibility of the usd prim in stage.

Example:

>>> # make prim not visible in the stage
>>> prim.set_visibility(visible=False)
set_world_pose(position: Optional[Sequence[float]] = None, orientation: Optional[Sequence[float]] = None) None

Ses prim’s pose with respect to the world’s frame

Warning

This method will change (teleport) the prim pose immediately to the indicated value

Parameters
  • position (Optional[Sequence[float]], optional) – position in the world frame of the prim. shape is (3, ). Defaults to None, which means left unchanged.

  • orientation (Optional[Sequence[float]], optional) – quaternion orientation in the world frame of the prim. quaternion is scalar-first (w, x, y, z). shape is (4, ). Defaults to None, which means left unchanged.

Hint

This method belongs to the methods used to set the prim state

Example:

>>> prim.set_world_pose(position=np.array([1.0, 0.5, 0.0]), orientation=np.array([1., 0., 0., 0.]))

Rigid Prim View

class RigidPrimView(prim_paths_expr: str, name: str = 'rigid_prim_view', positions: Optional[Union[numpy.ndarray, torch.Tensor, warp.types.array]] = None, translations: Optional[Union[numpy.ndarray, torch.Tensor, warp.types.array]] = None, orientations: Optional[Union[numpy.ndarray, torch.Tensor, warp.types.array]] = None, scales: Optional[Union[numpy.ndarray, torch.Tensor, warp.types.array]] = None, visibilities: Optional[Union[numpy.ndarray, torch.Tensor, warp.types.array]] = None, reset_xform_properties: bool = True, masses: Optional[Union[numpy.ndarray, torch.Tensor, warp.types.array]] = None, densities: Optional[Union[numpy.ndarray, torch.Tensor, warp.types.array]] = None, linear_velocities: Optional[Union[numpy.ndarray, torch.Tensor, warp.types.array]] = None, angular_velocities: Optional[Union[numpy.ndarray, torch.Tensor, warp.types.array]] = None, track_contact_forces: bool = False, prepare_contact_sensors: bool = True, disable_stablization: bool = True, contact_filter_prim_paths_expr: Optional[List[str]] = [], max_contact_count: int = 0)

Provides high level functions to deal with prims (one or many) that have Rigid Body API applied to them as well as their attributes/properties.

This class wraps all matching rigid prims found at the regex provided at the prim_paths_expr argument

Note

Each prim will have xformOp:orient, xformOp:translate and xformOp:scale only post-init, unless it is a non-root articulation link.

If the prims do not already have the Rigid Body API applied to them before init, it will apply it.

Warning

The rigid prim view object must be initialized in order to be able to operate on it. See the initialize method for more details.

Parameters
  • prim_paths_expr (str) – prim paths regex to encapsulate all prims that match it. example: “/World/Env[1-5]/Cube” will match /World/Env1/Cube, /World/Env2/Cube..etc. (a non regex prim path can also be used to encapsulate one rigid prim).

  • name (str, optional) – shortname to be used as a key by Scene class. Note: needs to be unique if the object is added to the Scene. Defaults to “rigid_prim_view”.

  • positions (Optional[Union[np.ndarray, torch.Tensor, wp.array]], optional) – default positions in the world frame of the prims. shape is (N, 3). Defaults to None, which means left unchanged.

  • translations (Optional[Union[np.ndarray, torch.Tensor, wp.array]], optional) – default translations in the local frame of the prims (with respect to its parent prims). shape is (N, 3). Defaults to None, which means left unchanged.

  • orientations (Optional[Union[np.ndarray, torch.Tensor, wp.array]], optional) – default quaternion orientations in the world/ local frame of the prims (depends if translation or position is specified). quaternion is scalar-first (w, x, y, z). shape is (N, 4). Defaults to None, which means left unchanged.

  • scales (Optional[Union[np.ndarray, torch.Tensor, wp.array]], optional) – local scales to be applied to the prim’s dimensions in the view. shape is (N, 3). Defaults to None, which means left unchanged.

  • visibilities (Optional[Union[np.ndarray, torch.Tensor, wp.array]], optional) – set to false for an invisible prim in the stage while rendering. shape is (N,). Defaults to None.

  • reset_xform_properties (bool, optional) – True if the prims don’t have the right set of xform properties (i.e: translate, orient and scale) ONLY and in that order. Set this parameter to False if the object were cloned using using the cloner api in omni.isaac.cloner. Defaults to True.

  • masses (Optional[Union[np.ndarray, torch.Tensor, wp.array]], optional) – mass in kg specified for each prim in the view. shape is (N,). Defaults to None.

  • densities (Optional[Union[np.ndarray, torch.Tensor, wp.array]], optional) – density in kg/m^3 specified for each prim in the view. shape is (N,). Defaults to None.

  • linear_velocities (Optional[Union[np.ndarray, torch.Tensor, wp.array]], optional) – default linear velocity of each prim in the view (to be applied in the first frame and on resets). Shape is (N, 3). Defaults to None.

  • angular_velocities (Optional[Union[np.ndarray, torch.Tensor, wp.array]], optional) – default angular velocity of each prim in the view (to be applied in the first frame and on resets). Shape is (N, 3). Defaults to None.

  • track_contact_forces (bool, Optional) – if enabled, the view will track the net contact forces on each rigid prim in the view

  • prepare_contact_sensors (bool, Optional) – if rigid prims in the view are not cloned from a prim in a prepared state, (although slow for large number of prims) this ensures that appropriate physics settings are applied on all the prim in the view.

  • disable_stablization (bool, optional) – disables the contact stabilization parameter in the physics context

  • contact_filter_prim_paths_expr (Optional[List[str]], Optional) – a list of filter expressions which allows for tracking contact forces between prims and this subset through get_contact_force_matrix().

  • max_contact_count (int, optional) – maximum number of contact data to report when detailed contact information is needed

Example:

>>> import omni.isaac.core.utils.stage as stage_utils
>>> from omni.isaac.cloner import GridCloner
>>> from omni.isaac.core.prims import RigidPrimView
>>> from pxr import UsdGeom
>>>
>>> env_zero_path = "/World/envs/env_0"
>>> num_envs = 5
>>>
>>> # clone the environment (num_envs)
>>> cloner = GridCloner(spacing=1.5)
>>> cloner.define_base_env(env_zero_path)
>>> UsdGeom.Xform.Define(stage_utils.get_current_stage(), env_zero_path)
>>> stage_utils.get_current_stage().DefinePrim(f"{env_zero_path}/Xform", "Xform")
>>> stage_utils.get_current_stage().DefinePrim(f"{env_zero_path}/Xform/Cube", "Cube")
>>> env_pos = cloner.clone(
...     source_prim_path=env_zero_path,
...     prim_paths=cloner.generate_paths("/World/envs/env", num_envs),
...     copy_from_source=True
... )
>>>
>>> # wrap the prims
>>> prims = RigidPrimView(prim_paths_expr="/World/envs/env.*/Xform", name="rigid_prim_view")
>>> prims
<omni.isaac.core.prims.rigid_prim_view.RigidPrimView object at 0x7f9a23b8bb80>
apply_forces(forces: Optional[Union[numpy.ndarray, torch.Tensor, warp.types.array]], indices: Optional[Union[numpy.ndarray, list, torch.Tensor, warp.types.array]] = None, is_global: bool = True) None

Applies forces to prims in the view.

Parameters
  • forces (Optional[Union[np.ndarray, torch.Tensor, wp.array]]) – forces to be applied to the prims.

  • indices (Optional[Union[np.ndarray, list, torch.Tensor, wp.array]], optional) – indices to specify which prims to manipulate. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

  • is_global (bool, optional) – True if forces are in the global frame. Otherwise False. Defaults to True.

Example:

>>> # apply an external force to all the rigid bodies to the indicated values.
>>> # Since there are 5 envs, the inertias are repeated 5 times
>>> forces = np.tile(np.array([2e5, 1e5, 0.0]), (num_envs, 1))
>>> prims.apply_forces(forces)
>>>
>>> # apply an external force to the rigid bodies for the first, middle and last of the 5 envs
>>> forces = np.tile(np.array([2e5, 1e5, 0.0]), (3, 1))
>>> prims.apply_forces(forces, indices=np.array([0, 2, 4]))
apply_forces_and_torques_at_pos(forces: Optional[Union[numpy.ndarray, torch.Tensor, warp.types.array]] = None, torques: Optional[Union[numpy.ndarray, torch.Tensor, warp.types.array]] = None, positions: Optional[Union[numpy.ndarray, torch.Tensor, warp.types.array]] = None, indices: Optional[Union[numpy.ndarray, list, torch.Tensor, warp.types.array]] = None, is_global: bool = True) None

Applies forces and torques to prims in the view. The forces and/or torques can be in local or global coordinates. The forces can applied at a location given by positions variable.

Parameters
  • forces (Optional[Union[np.ndarray, torch.Tensor, wp.array]]) – forces to be applied to the prims. If not specified, no force will be applied. Defaults to None (i.e: no forces will be applied).

  • torques (Optional[Union[np.ndarray, torch.Tensor, wp.array]]) – torques to be applied to the prims. If not specified, no torque will be applied. Defaults to None (i.e: no torques will be applied).

  • positions (Optional[Union[np.ndarray, torch.Tensor, wp.array]]) – position of the forces with respect to the body frame. If not specified, the forces are applied at the origin of the body frame. Defaults to None (i.e: applied forces will be at the origin of the body frame).

  • indices (Optional[Union[np.ndarray, list, torch.Tensor, wp.array]], optional) – indices to specify which prims to manipulate. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

  • is_global (bool, optional) – True if forces, torques, and positions are in the global frame. False if forces, torques, and positions are in the local frame. Defaults to True.

Example:

>>> # apply an external force and torque to all the rigid bodies to the indicated values.
>>> # Since there are 5 envs, the inertias are repeated 5 times
>>> forces = np.tile(np.array([2e5, 1e5, 0.0]), (num_envs, 1))
>>> torques = np.tile(np.array([2e5, 1e5, 0.0]), (num_envs, 1))
>>> prims.apply_forces_and_torques_at_pos(forces, torques)
>>>
>>> # apply an external force and torque to the rigid bodies for the first, middle and last of the 5 envs
>>> forces = np.tile(np.array([2e5, 1e5, 0.0]), (3, 1))
>>> torques = np.tile(np.array([2e5, 1e5, 0.0]), (3, 1))
>>> prims.apply_forces_and_torques_at_pos(forces, torques, indices=np.array([0, 2, 4]))
apply_visual_materials(visual_materials: Union[omni.isaac.core.materials.visual_material.VisualMaterial, List[omni.isaac.core.materials.visual_material.VisualMaterial]], weaker_than_descendants: Optional[Union[bool, List[bool]]] = None, indices: Optional[Union[numpy.ndarray, list, torch.Tensor, warp.types.array]] = None) None

Apply visual material to the prims and optionally their prim descendants.

Parameters
  • visual_materials (Union[VisualMaterial, List[VisualMaterial]]) – visual materials to be applied to the prims. Currently supports PreviewSurface, OmniPBR and OmniGlass. If a list is provided then its size has to be equal the view’s size or indices size. If one material is provided it will be applied to all prims in the view.

  • weaker_than_descendants (Optional[Union[bool, List[bool]]], optional) – True if the material shouldn’t override the descendants materials, otherwise False. Defaults to False. If a list of visual materials is provided then a list has to be provided with the same size for this arg as well.

  • indices (Optional[Union[np.ndarray, list, torch.Tensor, wp.array]], optional) – indices to specify which prims to manipulate. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

Raises
  • Exception – length of visual materials != length of prims indexed

  • Exception – length of visual materials != length of weaker descendants bools arg

Example:

>>> from omni.isaac.core.materials import OmniGlass
>>>
>>> # create a dark-red glass visual material
>>> material = OmniGlass(
...     prim_path="/World/material/glass",  # path to the material prim to create
...     ior=1.25,
...     depth=0.001,
...     thin_walled=False,
...     color=np.array([0.5, 0.0, 0.0])
... )
>>> prims.apply_visual_materials(material)
property count: int
Returns

Number of prims encapsulated in this view.

Return type

int

Example:

>>> prims.count
5
disable_gravities(indices: Optional[Union[numpy.ndarray, list, torch.Tensor, warp.types.array]] = None) None

Disable gravity on rigid bodies (enabled by default).

Parameters

indices (Optional[Union[np.ndarray, list, torch.Tensor, wp.array]], optional) – indices to specify which prims to manipulate. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

Example:

>>> # disable the gravity for all rigid bodies
>>> prims.disable_gravities()
>>>
>>> # disable the rigid body gravity for the first, middle and last of the 5 envs
>>> prims.disable_gravities(indices=np.array([0, 2, 4]))
disable_rigid_body_physics(indices: Optional[Union[numpy.ndarray, list, torch.Tensor, warp.types.array]] = None) None

Disable rigid body physics (enabled by default)

When disabled, the objects will not be moved by external forces such as gravity and collisions

Parameters

indices (Optional[Union[np.ndarray, list, torch.Tensor, wp.array]], optional) – indices to specify which prims to manipulate. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

Example:

>>> # enable the rigid body dynamics for all rigid bodies
>>> prims.disable_rigid_body_physics()
>>>
>>> # enable the rigid body dynamics for the first, middle and last of the 5 envs
>>> prims.disable_rigid_body_physics(indices=np.array([0, 2, 4]))
enable_gravities(indices: Optional[Union[numpy.ndarray, list, torch.Tensor, warp.types.array]] = None) None

Enable gravity on rigid bodies (enabled by default).

Parameters

indices (Optional[Union[np.ndarray, list, torch.Tensor, wp.array]], optional) – indices to specify which prims to manipulate. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

Example:

>>> # enable the gravity for all rigid bodies
>>> prims.enable_gravities()
>>>
>>> # enable the rigid body gravity for the first, middle and last of the 5 envs
>>> prims.enable_gravities(indices=np.array([0, 2, 4]))
enable_rigid_body_physics(indices: Optional[Union[numpy.ndarray, list, torch.Tensor, warp.types.array]] = None) None

Enable rigid body physics (enabled by default)

When enabled, the objects will be moved by external forces such as gravity and collisions

Parameters

indices (Optional[Union[np.ndarray, list, torch.Tensor, wp.array]], optional) – indices to specify which prims to manipulate. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

Example:

>>> # enable the rigid body dynamics for all rigid bodies
>>> prims.enable_rigid_body_physics()
>>>
>>> # enable the rigid body dynamics for the first, middle and last of the 5 envs
>>> prims.enable_rigid_body_physics(indices=np.array([0, 2, 4]))
get_angular_velocities(indices: Optional[Union[numpy.ndarray, list, torch.Tensor, warp.types.array]] = None, clone: bool = True) Union[numpy.ndarray, torch.Tensor, warp.types.indexedarray]

Get the angular velocities of prims in the view.

Parameters
  • indices (Optional[Union[np.ndarray, list, torch.Tensor, wp.array]], optional) – indices to specify which prims to query. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view)

  • clone (bool, optional) – True to return a clone of the internal buffer. Otherwise False. Defaults to True.

Returns

angular velocities of the prims in the view. shape is (M, 3).

Return type

Union[np.ndarray, torch.Tensor, wp.indexedarray]

Example:

>>> # get all rigid prim angular velocities. Returned shape is (5, 3) for the example: 5 envs, angular (3)
>>> prims.get_angular_velocities()
[[0. 0. 0.]
 [0. 0. 0.]
 [0. 0. 0.]
 [0. 0. 0.]
 [0. 0. 0.]]
>>>
>>> # get only the rigid prim angular velocities for the first, middle and last of the 5 envs
>>> # Returned shape is (5, 3) for the example: 3 envs selected, angular (3)
>>> prims.get_angular_velocities(indices=np.array([0, 2, 4]))
[[0. 0. 0.]
 [0. 0. 0.]
 [0. 0. 0.]]
get_applied_visual_materials(indices: Optional[Union[numpy.ndarray, list, torch.Tensor, warp.types.array]] = None) List[omni.isaac.core.materials.visual_material.VisualMaterial]

Get the current applied visual materials

Parameters

indices (Optional[Union[np.ndarray, list, torch.Tensor, wp.array]], optional) – indices to specify which prims to query. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

Returns

a list of the current applied visual materials to the prims if its type is currently supported.

Return type

List[VisualMaterial]

Example:

>>> # get all applied visual materials. Returned size is 5 for the example: 5 envs
>>> prims.get_applied_visual_materials()
[<omni.isaac.core.materials.omni_glass.OmniGlass object at 0x7f829c165de0>,
 <omni.isaac.core.materials.omni_glass.OmniGlass object at 0x7f829c165de0>,
 <omni.isaac.core.materials.omni_glass.OmniGlass object at 0x7f829c165de0>,
 <omni.isaac.core.materials.omni_glass.OmniGlass object at 0x7f829c165de0>,
 <omni.isaac.core.materials.omni_glass.OmniGlass object at 0x7f829c165de0>]
>>>
>>> # get the applied visual materials for the first, middle and last of the 5 envs. Returned size is 3
>>> prims.get_applied_visual_materials(indices=np.array([0, 2, 4]))
[<omni.isaac.core.materials.omni_glass.OmniGlass object at 0x7f829c165de0>,
 <omni.isaac.core.materials.omni_glass.OmniGlass object at 0x7f829c165de0>,
 <omni.isaac.core.materials.omni_glass.OmniGlass object at 0x7f829c165de0>]
get_coms(indices: Optional[Union[numpy.ndarray, List, torch.Tensor, warp.types.array]] = None, clone: bool = True) Union[numpy.ndarray, torch.Tensor, warp.types.indexedarray]

Get rigid body center of mass (COM) of bodies in the view.

Parameters
  • indices (Optional[Union[np.ndarray, List, torch.Tensor, wp.array]], optional) – indices to specify which prims to query. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

  • clone (bool, optional) – True to return a clone of the internal buffer. Otherwise False. Defaults to True.

Returns

rigid body center of mass positions and orientations of prims in the view. position shape is (M, 1, 3), orientation shape is (M, 1, 4).

Return type

Union[np.ndarray, torch.Tensor, wp.indexedarray]

Example:

>>> # get all rigid body center of mass.
>>> # Returned shape is (5, 1, 3) for positions and (5, 1, 4) for orientations for the example: 5 envs
>>> positions, orientations = prims.get_coms()
>>> positions
[[[0. 0. 0.]]
 [[0. 0. 0.]]
 [[0. 0. 0.]]
 [[0. 0. 0.]]
 [[0. 0. 0.]]]
>>> orientations
[[[1. 0. 0. 0.]]
 [[1. 0. 0. 0.]]
 [[1. 0. 0. 0.]]
 [[1. 0. 0. 0.]]
 [[1. 0. 0. 0.]]]
>>>
>>> # get rigid body center of mass for the first, middle and last of the 5 envs.
>>> # Returned shape is (3, 1, 3) for positions and (3, 1, 4) for orientations
>>> positions, orientations = prims.get_coms(indices=np.array([0, 2, 4]))
>>> positions
[[[0. 0. 0.]]
 [[0. 0. 0.]]
 [[0. 0. 0.]]]
>>> orientations
[[[1. 0. 0. 0.]]
 [[1. 0. 0. 0.]]
 [[1. 0. 0. 0.]]]
get_contact_force_data(indices: Optional[Union[numpy.ndarray, List, torch.Tensor, warp.types.array]] = None, clone: bool = True, dt: float = 1.0) Tuple[Union[numpy.ndarray, torch.Tensor, warp.types.indexedarray], Union[numpy.ndarray, torch.Tensor, warp.types.indexedarray], Union[numpy.ndarray, torch.Tensor, warp.types.indexedarray], Union[numpy.ndarray, torch.Tensor, warp.types.indexedarray], Union[numpy.ndarray, torch.Tensor, warp.types.indexedarray], Union[numpy.ndarray, torch.Tensor, warp.types.indexedarray]]

Get more detailed contact information between the prims in the view and the filter prims.

Specifically, this method provides individual contact normals, contact points, contact separations as well as contact forces for each pair (the sum of which equals the forces that the get_contact_force_matrix method provides as the force aggregate of a pair)

Given to the dynamic nature of collision between bodies, this method will provide buffers of contact data which are arranged sequentially for each pair. The starting index and the number of contact data points for each pair in this stream can be realized from pair_contacts_start_indices, and pair_contacts_count tensors. They both have a dimension of (num_shapes, _contact_view.num_filters) where _contact_view.num_filters is determined according to the contact_filter_prim_paths_expr parameter

Note

This method requires that the contact forces of the prims in the view be tracked by defining the contact_filter_prim_paths_expr argument to a list of the prim paths from which to generate the information and the max_contact_count argument be greater than 0 during view creation

Parameters
  • indices (Optional[Union[np.ndarray, list, torch.Tensor, wp.array]], optional) – indices to specify which prims to query. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

  • clone (bool, optional) – True to return a clone of the internal buffer. Otherwise False. Defaults to True.

  • dt (float) – time step multiplier to convert the underlying impulses to forces. If the default value is used then the forces are in fact contact impulses

Returns

Tuple[Union[np.ndarray, torch.Tensor, wp.indexedarray], Union[np.ndarray, torch.Tensor, wp.indexedarray], Union[np.ndarray, torch.Tensor, wp.indexedarray], Union[np.ndarray, torch.Tensor, wp.indexedarray], Union[np.ndarray, torch.Tensor, wp.indexedarray], Union[np.ndarray, torch.Tensor, wp.indexedarray]]: A set of buffers for normal forces with shape (max_contact_count, 1), points with shape (max_contact_count, 3), normals with shape (max_contact_count, 3), and distances with shape (max_contact_count, 1), as well as two tensors with shape (M, self.num_filters) to indicate the starting index and the number of contact data points per pair in the aforementioned buffers.

Example:

>>> # for the example, the cubes are on top of each other. The view was instantiated with the following
>>> # extra parameters: contact_filter_prim_paths_expr=["/World/envs/env_2/Xform"], max_contact_count=10
>>> # This indicates that only contacts with the middle cube will be reported
>>> data = prims.get_contact_force_data()
>>> data[0]  # normal forces
[[-156.449   ]
 [ -81.736336]
 [-169.73076 ]
 [ -82.397804]
 [ 110.11985 ]
 [  59.646057]
 [  98.660545]
 [  58.43006 ]
 [   0.      ]
 [   0.      ]]
>>> data[1]  # points
[[-0.50145745  0.49872556  0.7056795 ]
 [-0.50184476 -0.5010655   0.7057198 ]
 [ 0.49793154 -0.50147027  0.70576656]
 [ 0.4983363   0.49833822  0.70572615]
 [ 0.49818155 -0.5016888   1.7058725 ]
 [ 0.49856627  0.4913648   1.7058672 ]
 [-0.49732465  0.4915302   1.705814  ]
 [-0.49748957 -0.501303    1.7058194 ]
 [ 0.          0.          0.        ]
 [ 0.          0.          0.        ]]
>>> data[2]  # normals
[[ 1.6479074e-05 -1.6995813e-05  1.0000000e+00]
 [ 1.6479074e-05 -1.6995813e-05  1.0000000e+00]
 [ 1.6479074e-05 -1.6995813e-05  1.0000000e+00]
 [ 1.6479074e-05 -1.6995813e-05  1.0000000e+00]
 [ 1.6479074e-05 -1.6995813e-05  1.0000000e+00]
 [ 1.6479074e-05 -1.6995813e-05  1.0000000e+00]
 [ 1.6479074e-05 -1.6995813e-05  1.0000000e+00]
 [ 1.6479074e-05 -1.6995813e-05  1.0000000e+00]
 [ 0.0000000e+00  0.0000000e+00  0.0000000e+00]
 [ 0.0000000e+00  0.0000000e+00  0.0000000e+00]]
>>> data[3]  # distances
[[ 6.3175990e-05]
 [ 5.8271162e-06]
 [-5.7399273e-05]
 [-1.0989098e-08]
 [ 1.6338757e-04]
 [ 1.4112510e-04]
 [ 7.1585178e-05]
 [ 9.3835908e-05]
 [ 0.0000000e+00]
 [ 0.0000000e+00]]
>>> data[4]  # pair contacts count
[[0]
 [4]
 [0]
 [4]
 [0]]
>>> data[5]  # start indices of pair contacts
[[0]
 [0]
 [4]
 [4]
 [8]]
get_contact_force_matrix(indices: Optional[Union[numpy.ndarray, List, torch.Tensor, warp.types.array]] = None, clone: bool = True, dt: float = 1.0) Union[numpy.ndarray, torch.Tensor, warp.types.indexedarray]

Return the contact forces between the prims in the view and the filter prims

E.g., a matrix of dimension (self.count, _contact_view.num_filters, 3) where _contact_view.num_filters is determined according to the contact_filter_prim_paths_expr parameter

Note

This method requires that the contact forces of the prims in the view be tracked by defining the contact_filter_prim_paths_expr argument to a list of the prim paths from which to generate the information and the max_contact_count argument be greater than 0 during view creation

Parameters
  • indices (Optional[Union[np.ndarray, list, torch.Tensor, wp.array]], optional) – indices to specify which prims to query. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

  • clone (bool, optional) – True to return a clone of the internal buffer. Otherwise False. Defaults to True.

  • dt (float) – time step multiplier to convert the underlying impulses to forces. If the default value is used then the forces are in fact contact impulses

Returns

Net contact forces of the prims with shape (M, self._contact_view.num_filters, 3).

Return type

Union[np.ndarray, torch.Tensor, wp.indexedarray]

Example:

>>> # for the example, the cubes are on top of each other. The view was instantiated with the following
>>> # extra parameters: contact_filter_prim_paths_expr=["/World/envs/env_2/Xform"], max_contact_count=10
>>> # This indicates that only contacts with the middle cube will be reported
>>> prims.get_contact_force_matrix()
[[[ 0.0000000e+00  0.0000000e+00  0.0000000e+00]]
 [[-7.8665102e-03  8.3034458e-03 -4.9063504e+02]]
 [[ 0.0000000e+00  0.0000000e+00  0.0000000e+00]]
 [[ 5.2445102e-03 -5.5358098e-03  3.2710065e+02]]
 [[ 0.0000000e+00  0.0000000e+00  0.0000000e+00]]]
get_current_dynamic_state() omni.isaac.core.utils.types.DynamicsViewState

Get the current rigid body states (position, orientation and linear and angular velocities)

Returns

the dynamic state of the rigid bodies

Return type

DynamicState

Example:

>>> # for the example the rigid bodies are in free fall
>>> state = prims.get_default_state()
<omni.isaac.core.utils.types.DynamicsViewState object at 0x7f182bd72590>
>>> state
>>> state.positions
[[   1.5       -0.75    -207.76808]
 [   1.5        0.75    -207.76808]
 [   0.        -0.75    -207.76808]
 [   0.         0.75    -207.76808]
 [  -1.5       -0.75    -207.76808]]
>>> state.orientations
[[1. 0. 0. 0.]
 [1. 0. 0. 0.]
 [1. 0. 0. 0.]
 [1. 0. 0. 0.]
 [1. 0. 0. 0.]]
>>> state.linear_velocities
[[  0.         0.       -63.765312]
 [  0.         0.       -63.765312]
 [  0.         0.       -63.765312]
 [  0.         0.       -63.765312]
 [  0.         0.       -63.765312]]
>>> state.angular_velocities
[[0. 0. 0.]
 [0. 0. 0.]
 [0. 0. 0.]
 [0. 0. 0.]
 [0. 0. 0.]]
get_default_state() omni.isaac.core.utils.types.DynamicsViewState

Get the default state (position, orientation and linear and angular velocities) of prims in the view, that will be used after each reset.

Returns

returns the default state of the prims that is used after each reset.

Return type

DynamicsViewState

Example:

>>> state = prims.get_default_state()
<omni.isaac.core.utils.types.DynamicsViewState object at 0x7f184e555480>
>>> state
>>> state.positions
[[ 1.4999989e+00 -7.4999851e-01 -1.5118626e-07]
 [ 1.4999989e+00  7.5000149e-01 -2.5988294e-07]
 [-1.0017333e-06 -7.4999845e-01  7.6070329e-08]
 [-9.5906785e-07  7.5000149e-01  1.0593490e-07]
 [-1.5000011e+00 -7.4999851e-01  1.9655154e-07]]
>>> state.orientations
[[ 9.9999994e-01 -8.8168377e-07 -4.1946004e-07 -1.5067183e-08]
 [ 9.9999994e-01 -8.8691013e-07 -4.2665880e-07 -2.7188951e-09]
 [ 1.0000000e+00 -9.5171310e-07 -2.2615541e-07  5.5922797e-08]
 [ 1.0000000e+00 -8.9923367e-07 -1.4408238e-07  1.3476099e-08]
 [ 1.0000000e+00 -7.9806580e-07 -1.3064776e-07  5.3154917e-08]]
>>> state.linear_velocities
[[0. 0. 0.]
 [0. 0. 0.]
 [0. 0. 0.]
 [0. 0. 0.]
 [0. 0. 0.]]
>>> state.angular_velocities
[[0. 0. 0.]
 [0. 0. 0.]
 [0. 0. 0.]
 [0. 0. 0.]
 [0. 0. 0.]]
get_densities(indices: Optional[Union[numpy.ndarray, list, torch.Tensor, warp.types.array]] = None) Union[numpy.ndarray, torch.Tensor, warp.types.indexedarray]

Get densities of prims in the view.

Parameters

indices (Optional[Union[np.ndarray, list, torch.Tensor, wp.array]], optional) – indices to specify which prims to query. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view)

Returns

densities of prims in the view in kg/m^3. shape (M,).

Return type

Union[np.ndarray, torch.Tensor, wp.indexedarray]

Example:

>>> # get all rigid body densities. Returned shape is (5,) for the example: 5 envs
>>> prims.get_densities()
[0. 0. 0. 0. 0.]
>>>
>>> # get rigid body densities for the first, middle and last of the 5 envs. Returned shape is (3,)
>>> prims.get_densities(indices=np.array([0, 2, 4]))
[0. 0. 0.]
get_inertias(indices: Optional[Union[numpy.ndarray, List, torch.Tensor, warp.types.array]] = None, clone: bool = True) Union[numpy.ndarray, torch.Tensor, warp.types.indexedarray]

Get rigid body inertias of prims in the view.

Parameters
  • indices (Optional[Union[np.ndarray, List, torch.Tensor, wp.array]], optional) – indices to specify which prims to query. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

  • clone (bool, optional) – True to return a clone of the internal buffer. Otherwise False. Defaults to True.

Returns

rigid body inertias of prims in the view. Shape is (M, 9).

Return type

Union[np.ndarray, torch.Tensor, wp.indexedarray]

Example:

>>> # get all rigid body inertias. Returned shape is (5, 9) for the example: 5 envs
>>> prims.get_inertias()
[[166.66667  0.  0.  0.  166.66667  0.  0.  0.  166.66667]
 [166.66667  0.  0.  0.  166.66667  0.  0.  0.  166.66667]
 [166.66667  0.  0.  0.  166.66667  0.  0.  0.  166.66667]
 [166.66667  0.  0.  0.  166.66667  0.  0.  0.  166.66667]
 [166.66667  0.  0.  0.  166.66667  0.  0.  0.  166.66667]]
>>>
>>> # get rigid body inertias for the first, middle and last of the 5 envs. Returned shape is (3, 9)
>>> prims.get_inertias(indices=np.array([0, 2, 4]))
[[166.66667  0.  0.  0.  166.66667  0.  0.  0.  166.66667]
 [166.66667  0.  0.  0.  166.66667  0.  0.  0.  166.66667]
 [166.66667  0.  0.  0.  166.66667  0.  0.  0.  166.66667]]
get_inv_inertias(indices: Optional[Union[numpy.ndarray, List, torch.Tensor, warp.types.array]] = None, clone: bool = True) Union[numpy.ndarray, torch.Tensor, warp.types.indexedarray]

Get rigid body inverse inertias of prims in the view.

Parameters
  • indices (Optional[Union[np.ndarray, List, torch.Tensor, wp.array]], optional) – indices to specify which prims to query. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

  • clone (bool, optional) – True to return a clone of the internal buffer. Otherwise False. Defaults to True.

Returns

rigid body inverse inertias of prims in the view. Shape is (M, 9).

Return type

Union[np.ndarray, torch.Tensor, wp.indexedarray]

Example:

>>> # get all rigid body inverse inertias. Returned shape is (5, 9) for the example: 5 envs
>>> prims.get_inv_inertias()
[[0.006 0.    0.    0.    0.006 0.    0.    0.    0.006]
 [0.006 0.    0.    0.    0.006 0.    0.    0.    0.006]
 [0.006 0.    0.    0.    0.006 0.    0.    0.    0.006]
 [0.006 0.    0.    0.    0.006 0.    0.    0.    0.006]
 [0.006 0.    0.    0.    0.006 0.    0.    0.    0.006]]
>>>
>>> # get rigid body inverse inertias for the first, middle and last of the 5 envs. Returned shape is (3, 9)
>>> prims.get_inv_inertias(indices=np.array([0, 2, 4]))
[[0.006 0.    0.    0.    0.006 0.    0.    0.    0.006]
 [0.006 0.    0.    0.    0.006 0.    0.    0.    0.006]
 [0.006 0.    0.    0.    0.006 0.    0.    0.    0.006]]
get_inv_masses(indices: Optional[Union[numpy.ndarray, List, torch.Tensor, warp.types.array]] = None, clone: bool = True) Union[numpy.ndarray, torch.Tensor, warp.types.indexedarray]

Get rigid body inverse masses of prims in the view.

Parameters
  • indices (Optional[Union[np.ndarray, List, torch.Tensor, wp.array]], optional) – indices to specify which prims to query. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

  • clone (bool, optional) – True to return a clone of the internal buffer. Otherwise False. Defaults to True.

Returns

rigid body inverse masses of prims in the view. Shape is (M,).

Return type

Union[np.ndarray, torch.Tensor, wp.indexedarray]

Example:

>>> # get all rigid body inverse masses. Returned shape is (5, 1) for the example: 5 envs
>>> prims.get_inv_masses()
[[0.001]
 [0.001]
 [0.001]
 [0.001]
 [0.001]]
>>>
>>> # get rigid body inverse masses for the first, middle and last of the 5 envs. Returned shape is (3, 1)
>>> prims.get_inv_masses(indices=np.array([0, 2, 4]))
[[0.001]
 [0.001]
 [0.001]]
get_linear_velocities(indices: Optional[Union[numpy.ndarray, list, torch.Tensor, warp.types.array]] = None, clone: bool = True) Union[numpy.ndarray, torch.Tensor, warp.types.indexedarray]

Get the linear velocities of prims in the view.

Parameters
  • indices (Optional[Union[np.ndarray, list, torch.Tensor, wp.array]], optional) – indices to specify which prims to query. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view)

  • clone (bool, optional) – True to return a clone of the internal buffer. Otherwise False. Defaults to True.

Returns

linear velocities of the prims in the view. shape is (M, 3).

Return type

Union[np.ndarray, torch.Tensor, wp.indexedarray]

Example:

>>> # get all rigid prim linear velocities. Returned shape is (5, 3) for the example: 5 envs, linear (3)
>>> prims.get_linear_velocities()
[[0. 0. 0.]
 [0. 0. 0.]
 [0. 0. 0.]
 [0. 0. 0.]
 [0. 0. 0.]]
>>>
>>> # get only the rigid prim linear velocities for the first, middle and last of the 5 envs.
>>> # Returned shape is (3, 3) for the example: 3 envs selected, linear (3)
>>> prims.get_linear_velocities(indices=np.array([0, 2, 4]))
[[0. 0. 0.]
 [0. 0. 0.]
 [0. 0. 0.]]
get_local_poses(indices: Optional[Union[numpy.ndarray, list, torch.Tensor, warp.types.array]] = None) Union[Tuple[numpy.ndarray, numpy.ndarray], Tuple[torch.Tensor, torch.Tensor], Tuple[warp.types.indexedarray, warp.types.indexedarray]]

Get prim poses in the view with respect to the local frame (the prim’s parent frame).

Parameters

indices (Optional[Union[np.ndarray, list, torch.Tensor, wp.array]], optional) – indices to specify which prims to query. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view)

Returns

first index is positions in the local frame of the prims. shape is (M, 3). second index is quaternion orientations in the local frame of the prims. quaternion is scalar-first (w, x, y, z). shape is (M, 4).

Return type

Union[Tuple[np.ndarray, np.ndarray], Tuple[torch.Tensor, torch.Tensor], Tuple[wp.indexedarray, wp.indexedarray]]

Example:

>>> # get all rigid prim poses with respect to the local frame.
>>> # Returned shape is position (5, 3) and orientation (5, 4) for the example: 5 envs
>>> positions, orientations = prims.get_local_poses()
>>> positions
[[-1.0728836e-06  1.4901161e-06 -1.5118626e-07]
 [-1.0728836e-06  1.4901161e-06 -2.5988294e-07]
 [-1.0017333e-06  1.5497208e-06  7.6070329e-08]
 [-9.5906785e-07  1.4901161e-06  1.0593490e-07]
 [-1.0728836e-06  1.4901161e-06  1.9655154e-07]]
>>> orientations
[[ 1.0000000e+00 -8.8174920e-07 -4.1949116e-07 -1.5068302e-08]
 [ 1.0000000e+00 -8.8696777e-07 -4.2668654e-07 -2.7190719e-09]
 [ 1.0000000e+00 -9.5164734e-07 -2.2613979e-07  5.5918935e-08]
 [ 1.0000000e+00 -8.9923157e-07 -1.4408204e-07  1.3476067e-08]
 [ 1.0000000e+00 -7.9806864e-07 -1.3064822e-07  5.3155105e-08]]
>>>
>>> # get only the rigid prim poses with respect to the local frame for the first, middle and last of the 5 envs.
>>> # Returned shape is position (3, 3) and orientation (3, 4) for the example: 3 envs selected
>>> positions, orientations = prims.get_local_poses(indices=np.array([0, 2, 4]))
>>> positions
[[-1.0728836e-06  1.4901161e-06 -1.5118626e-07]
 [-1.0017333e-06  1.5497208e-06  7.6070329e-08]
 [-1.0728836e-06  1.4901161e-06  1.9655154e-07]]
>>> orientations
[[ 1.0000000e+00 -8.8174920e-07 -4.1949116e-07 -1.5068302e-08]
 [ 1.0000000e+00 -9.5164734e-07 -2.2613979e-07  5.5918935e-08]
 [ 1.0000000e+00 -7.9806864e-07 -1.3064822e-07  5.3155105e-08]]
get_local_scales(indices: Optional[Union[numpy.ndarray, list, torch.Tensor, warp.types.array]] = None) Union[numpy.ndarray, torch.Tensor, warp.types.indexedarray]

Get prim scales in the view with respect to the local frame (the parent’s frame).

Parameters

indices (Optional[Union[np.ndarray, list, torch.Tensor, wp.array]], optional) – indices to specify which prims to query. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

Returns

scales applied to the prim’s dimensions in the local frame. shape is (M, 3).

Return type

Union[np.ndarray, torch.Tensor, wp.indexedarray]

Example:

>>> # get all prims scales with respect to the local frame.
>>> # Returned shape is (5, 3) for the example: 5 envs
>>> prims.get_local_scales()
[[1. 1. 1.]
 [1. 1. 1.]
 [1. 1. 1.]
 [1. 1. 1.]
 [1. 1. 1.]]
>>>
>>> # get only the prims scales with respect to the local frame for the first, middle and last of the 5 envs.
>>> # Returned shape is (3, 3) for the example: 3 envs selected
>>> prims.get_local_scales(indices=np.array([0, 2, 4]))
[[1. 1. 1.]
 [1. 1. 1.]
 [1. 1. 1.]]
get_masses(indices: Optional[Union[numpy.ndarray, List, torch.Tensor, warp.types.array]] = None, clone: bool = True) Union[numpy.ndarray, torch.Tensor, warp.types.indexedarray]

Get rigid body masses of prims in the view.

Parameters
  • indices (Optional[Union[np.ndarray, List, torch.Tensor, wp.array]], optional) – indices to specify which prims to query. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

  • clone (bool, optional) – True to return a clone of the internal buffer. Otherwise False. Defaults to True.

Returns

masses of in kg of prims in the view. shape is (M,).

Return type

Union[np.ndarray, torch.Tensor, wp.indexedarray]

Example:

>>> # get all rigid body masses. Returned shape is (5,) for the example: 5 envs
>>> prims.get_masses()
[999.99994 999.99994 999.99994 999.99994 999.99994]
>>>
>>> # get rigid body masses for the first, middle and last of the 5 envs. Returned shape is (3,)
>>> prims.get_masses(indices=np.array([0, 2, 4]))
[999.99994 999.99994 999.99994]
get_net_contact_forces(indices: Optional[Union[numpy.ndarray, List, torch.Tensor, warp.types.array]] = None, clone: bool = True, dt: float = 1.0) Union[numpy.ndarray, torch.Tensor, warp.types.indexedarray]

Return the net contact forces on prims

Note

This method requires that the contact forces of the prims in the view be tracked by defining the track_contact_forces argument to True (default to False) during view creation

Parameters
  • indices (Optional[Union[np.ndarray, list, torch.Tensor, wp.array]], optional) – indices to specify which prims to query. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

  • clone (bool, optional) – True to return a clone of the internal buffer. Otherwise False. Defaults to True.

  • dt (float) – time step multiplier to convert the underlying impulses to forces. If the default value is used then the forces are in fact contact impulses

Returns

Net contact forces of the prims with shape (M,3).

Return type

Union[np.ndarray, torch.Tensor, wp.indexedarray]

Example:

>>> # get the net contact force on all rigid bodies. Returned shape is (5, 3).
>>> # For the example the view was instantiated with the extra parameter: track_contact_forces=True
>>> prims.get_net_contact_forces()
[[2.1967362e-05 0.0000000e+00 1.6349771e+02]
 [2.1967124e-05 0.0000000e+00 1.6349591e+02]
 [2.1967891e-05 0.0000000e+00 1.6350165e+02]
 [2.1967257e-05 0.0000000e+00 1.6349693e+02]
 [2.1966895e-05 0.0000000e+00 1.6349425e+02]]
>>>
>>> # get the net contact force on the rigid bodies for the first, middle and last of the 5 envs
>>> prims.get_net_contact_forces(indices=np.array([0, 2, 4]))
[[2.1967362e-05 0.0000000e+00 1.6349771e+02]
 [2.1967891e-05 0.0000000e+00 1.6350165e+02]
 [2.1966895e-05 0.0000000e+00 1.6349425e+02]]
get_sleep_thresholds(indices: Optional[Union[numpy.ndarray, list, torch.Tensor, warp.types.array]] = None) Union[numpy.ndarray, torch.Tensor, warp.types.indexedarray]

Get sleep thresholds of prims in the view.

Search for Rigid Body Dynamics > Sleeping in PhysX docs for more details

Parameters

indices (Optional[Union[np.ndarray, list, torch.Tensor, wp.array]], optional) – indices to specify which prims to query. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view)

Returns

Mass-normalized kinetic energy threshold below which an actor may go to sleep. Range: [0, inf). Defaults: 0.00005 * tolerancesSpeed* tolerancesSpeed Units: distance^2 / second^2. shape (M,).

Return type

Union[np.ndarray, torch.Tensor, wp.indexedarray]

Example:

>>> # get all sleep threshold. Returned shape is (5,) for the example: 5 envs
>>> prims.get_sleep_thresholds()
[5.e-05 5.e-05 5.e-05 5.e-05 5.e-05]
>>>
>>> # get sleep threshold for the first, middle and last of the 5 envs. Returned shape is (3,)
>>> prims.get_sleep_thresholds(indices=np.array([0, 2, 4]))
[5.e-05 5.e-05 5.e-05]
get_velocities(indices: Optional[Union[numpy.ndarray, list, torch.Tensor, warp.types.array]] = None, clone: bool = True) Union[numpy.ndarray, torch.Tensor, warp.types.indexedarray]

Get the linear and angular velocities of prims in the view.

Parameters
  • indices (Optional[Union[np.ndarray, list, torch.Tensor, wp.array]], optional) – indices to specify which prims to query. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view)

  • clone (bool, optional) – True to return a clone of the internal buffer. Otherwise False. Defaults to True.

Returns

linear and angular velocities of the prims in the view concatenated. shape is (M, 6).

Return type

Union[np.ndarray, torch.Tensor, wp.indexedarray]

Example:

>>> # get all rigid prim velocities. Returned shape is (5, 6) for the example: 5 envs, linear (3) and angular (3)
>>> prims.get_velocities()
[[0. 0. 0. 0. 0. 0.]
 [0. 0. 0. 0. 0. 0.]
 [0. 0. 0. 0. 0. 0.]
 [0. 0. 0. 0. 0. 0.]
 [0. 0. 0. 0. 0. 0.]]
>>>
>>> # get only the rigid prim velocities for the first, middle and last of the 5 envs.
>>> # Returned shape is (3, 6) for the example: 3 envs selected, linear (3) and angular (3)
>>> prims.get_velocities(indices=np.array([0, 2, 4]))
[[0. 0. 0. 0. 0. 0.]
 [0. 0. 0. 0. 0. 0.]
 [0. 0. 0. 0. 0. 0.]]
get_visibilities(indices: Optional[Union[numpy.ndarray, list, torch.Tensor, warp.types.array]] = None) Union[numpy.ndarray, torch.Tensor, warp.types.indexedarray]

Returns the current visibilities of the prims in stage.

Parameters

indices (Optional[Union[np.ndarray, list, torch.Tensor, wp.array]], optional) – indices to specify which prims to query. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

Returns

Shape (M,) with type bool, where each item holds True

if the prim is visible in stage. False otherwise.

Return type

Union[np.ndarray, torch.Tensor, wp.indexedarray]

Example:

>>> # get all visibilities. Returned shape is (5,) for the example: 5 envs
>>> prims.get_visibilities()
[ True  True  True  True  True]
>>>
>>> # get the visibilities for the first, middle and last of the 5 envs. Returned shape is (3,)
>>> prims.get_visibilities(indices=np.array([0, 2, 4]))
[ True  True  True]
get_world_poses(indices: Optional[Union[numpy.ndarray, list, torch.Tensor, warp.types.array]] = None, clone: bool = True) Union[Tuple[numpy.ndarray, numpy.ndarray], Tuple[torch.Tensor, torch.Tensor], Tuple[warp.types.indexedarray, warp.types.indexedarray]]

Get the poses of the prims in the view with respect to the world’s frame.

Parameters
  • indices (Optional[Union[np.ndarray, list, torch.Tensor, wp.array]], optional) – indices to specify which prims to query. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

  • clone (bool, optional) – True to return a clone of the internal buffer. Otherwise False. Defaults to True.

Returns

first index is positions in the world frame of the prims. shape is (M, 3). second index is quaternion orientations in the world frame of the prims. quaternion is scalar-first (w, x, y, z). shape is (M, 4).

Return type

Union[Tuple[np.ndarray, np.ndarray], Tuple[torch.Tensor, torch.Tensor], Tuple[wp.indexedarray, wp.indexedarray]]

Example:

>>> # get all rigid prim poses with respect to the world's frame.
>>> # Returned shape is position (5, 3) and orientation (5, 4) for the example: 5 envs
>>> positions, orientations = prims.get_world_poses()
>>> positions
[[ 1.4999989e+00 -7.4999851e-01 -1.5118626e-07]
 [ 1.4999989e+00  7.5000149e-01 -2.5988294e-07]
 [-1.0017333e-06 -7.4999845e-01  7.6070329e-08]
 [-9.5906785e-07  7.5000149e-01  1.0593490e-07]
 [-1.5000011e+00 -7.4999851e-01  1.9655154e-07]]
>>> orientations
[[ 9.9999994e-01 -8.8168377e-07 -4.1946004e-07 -1.5067183e-08]
 [ 9.9999994e-01 -8.8691013e-07 -4.2665880e-07 -2.7188951e-09]
 [ 1.0000000e+00 -9.5171310e-07 -2.2615541e-07  5.5922797e-08]
 [ 1.0000000e+00 -8.9923367e-07 -1.4408238e-07  1.3476099e-08]
 [ 1.0000000e+00 -7.9806580e-07 -1.3064776e-07  5.3154917e-08]]
>>>
>>> # get only the rigid prim poses with respect to the world's frame for the first, middle and last of the 5 envs.
>>> # Returned shape is position (3, 3) and orientation (3, 4) for the example: 3 envs selected
>>> positions, orientations = prims.get_world_poses(indices=np.array([0, 2, 4]))
>>> positions
[[ 1.4999989e+00 -7.4999851e-01 -1.5118626e-07]
 [-1.0017333e-06 -7.4999845e-01  7.6070329e-08]
 [-1.5000011e+00 -7.4999851e-01  1.9655154e-07]]
>>> orientations
[[ 9.9999994e-01 -8.8168377e-07 -4.1946004e-07 -1.5067183e-08]
 [ 1.0000000e+00 -9.5171310e-07 -2.2615541e-07  5.5922797e-08]
 [ 1.0000000e+00 -7.9806580e-07 -1.3064776e-07  5.3154917e-08]]
get_world_scales(indices: Optional[Union[numpy.ndarray, list, torch.Tensor, warp.types.array]] = None) Union[numpy.ndarray, torch.Tensor, warp.types.indexedarray]

Get prim scales in the view with respect to the world’s frame

Parameters

indices (Optional[Union[np.ndarray, list, torch.Tensor, wp.array]], optional) – indices to specify which prims to query. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

Returns

scales applied to the prim’s dimensions in the world frame. shape is (M, 3).

Return type

Union[np.ndarray, torch.Tensor, wp.indexedarray]

Example:

>>> # get all prims scales with respect to the world's frame.
>>> # Returned shape is (5, 3) for the example: 5 envs
>>> prims.get_world_scales()
[[1. 1. 1.]
 [1. 1. 1.]
 [1. 1. 1.]
 [1. 1. 1.]
 [1. 1. 1.]]
>>>
>>> # get only the prims scales with respect to the world's frame for the first, middle and last of the 5 envs.
>>> # Returned shape is (3, 3) for the example: 3 envs selected
>>> prims.get_world_scales(indices=np.array([0, 2, 4]))
[[1. 1. 1.]
 [1. 1. 1.]
 [1. 1. 1.]]
initialize(physics_sim_view: Optional[omni.physics.tensors.bindings._physicsTensors.SimulationView] = None) None

Create a physics simulation view if not passed and set other properties using the PhysX tensor API

Note

If the rigid prim view has been added to the world scene (e.g., world.scene.add(prims)), it will be automatically initialized when the world is reset (e.g., world.reset()).

Warning

This method needs to be called after each hard reset (e.g., Stop + Play on the timeline) before interacting with any other class method.

Parameters

physics_sim_view (omni.physics.tensors.SimulationView, optional) – current physics simulation view. Defaults to None.

Example:

>>> prims.initialize()

Returns: bool: True if the prim corresponds to a non root link in an articulation. Otherwise False.

is_physics_handle_valid() bool

Check if rigid prim view’s physics handler is initialized

Warning

If the physics handler is not valid many of the methods that requires PhysX will return None.

Returns

True if the physics handle of the view is valid (i.e physics is initialized for the view). Otherwise False.

Return type

bool

Example:

>>> prims.is_physics_handle_valid()
True
is_valid(indices: Optional[Union[numpy.ndarray, list, torch.Tensor, warp.types.array]] = None) bool

Check that all prims have a valid USD Prim

Parameters

indices (Optional[Union[np.ndarray, list, torch.Tensor, wp.array]], optional) – indices to specify which prims to query. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

Returns

True if all prim paths specified in the view correspond to a valid prim in stage. False otherwise.

Return type

bool

Example:

>>> prims.is_valid()
True
is_visual_material_applied(indices: Optional[Union[numpy.ndarray, list, torch.Tensor, warp.types.array]] = None) List[bool]

Check if there is a visual material applied

Parameters

indices (Optional[Union[np.ndarray, list, torch.Tensor, wp.array]], optional) – indices to specify which prims to query. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

Returns

True if there is a visual material applied is applied to the corresponding prim in the view. False otherwise.

Return type

List[bool]

Example:

>>> # given a visual material that is applied only to the first and the last environment
>>> prims.is_visual_material_applied()
[True, False, False, False, True]
>>>
>>> # check for the first, middle and last of the 5 envs
>>> prims.is_visual_material_applied(indices=np.array([0, 2, 4]))
[True, False, True]
property name: str

Returns: str: name given to the prims view when instantiating it.

property num_shapes: int
Returns

number of rigid shapes for the prims in the view.

Return type

int

Example:

>>> prims.num_shapes
1
post_reset() None

Reset the rigid prims to their default states (positions, orientations and linear and angular velocities)

Example:

>>> prims.post_reset()
property prim_paths: List[str]
Returns

list of prim paths in the stage encapsulated in this view.

Return type

List[str]

Example:

>>> prims.prim_paths
['/World/envs/env_0', '/World/envs/env_1', '/World/envs/env_2', '/World/envs/env_3', '/World/envs/env_4']
property prims: List[pxr.Usd.Prim]
Returns

List of USD Prim objects encapsulated in this view.

Return type

List[Usd.Prim]

Example:

>>> prims.prims
[Usd.Prim(</World/envs/env_0>), Usd.Prim(</World/envs/env_1>), Usd.Prim(</World/envs/env_2>),
 Usd.Prim(</World/envs/env_3>), Usd.Prim(</World/envs/env_4>)]
set_angular_velocities(velocities: Optional[Union[numpy.ndarray, torch.Tensor, warp.types.array]], indices: Optional[Union[numpy.ndarray, list, torch.Tensor, warp.types.array]] = None) None

Set the angular velocities of the prims in the view

The method does this through the physx API only. It has to be called after initialization. Note: This method is not supported for the gpu pipeline. set_velocities method should be used instead.

Warning

This method will immediately set the rigid prim state

Parameters
  • velocities (Optional[Union[np.ndarray, torch.Tensor, wp.array]]) – angular velocities to set the rigid prims to. shape is (M, 3).

  • indices (Optional[Union[np.ndarray, list, torch.Tensor, wp.array]], optional) – indices to specify which prims to manipulate. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

Hint

This method belongs to the methods used to set the rigid prim kinematic state:

set_velocities (set_linear_velocities, set_angular_velocities)

Example:

>>> # set each rigid prim linear velocity to (5.0, 5.0, 5.0)
>>> velocities = np.full((num_envs, 3), fill_value=5.0)
>>> prims.set_angular_velocities(velocities)
>>>
>>> # set only the rigid prim linear velocities for the first, middle and last of the 5 envs
>>> velocities = np.full((3, 3), fill_value=5.0)
>>> prims.set_angular_velocities(velocities, indices=np.array([0, 2, 4]))
set_coms(positions: Optional[Union[numpy.ndarray, torch.Tensor, warp.types.array]] = None, orientations: Optional[Union[numpy.ndarray, torch.Tensor, warp.types.array]] = None, indices: Optional[Union[numpy.ndarray, List, torch.Tensor, warp.types.array]] = None) None

Set body center of mass (COM) positions and orientations for bodies in the view.

Parameters
  • positions (Union[np.ndarray, torch.Tensor, wp.array]) – body center of mass positions for bodies in the view. shape (M, 1, 3).

  • orientations (Union[np.ndarray, torch.Tensor, wp.array]) – body center of mass orientations for bodies in the view. shape (M, 1, 4).

  • indices (Optional[Union[np.ndarray, List, torch.Tensor, wp.array]], optional) – indices to specify which prims to manipulate. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

Example:

>>> # set the center of mass for all the rigid bodies to the specified values.
>>> # Since there are 5 envs, the inertias are repeated 5 times
>>> positions = np.tile(np.array([0.01, 0.02, 0.03]), (num_envs, 1, 1))
>>> orientations = np.tile(np.array([1.0, 0.0, 0.0, 0.0]), (num_envs, 1, 1))
>>> prims.set_coms(positions, orientations)
>>>
>>> # set the rigid bodies center of mass for the first, middle and last of the 5 envs
>>> positions = np.tile(np.array([0.01, 0.02, 0.03]), (3, 1, 1))
>>> orientations = np.tile(np.array([1.0, 0.0, 0.0, 0.0]), (3, 1, 1))
>>> prims.set_coms(positions, orientations, indices=np.array([0, 2, 4]))
set_default_state(positions: Optional[Union[numpy.ndarray, torch.Tensor, warp.types.array]] = None, orientations: Optional[Union[numpy.ndarray, torch.Tensor, warp.types.array]] = None, linear_velocities: Optional[Union[numpy.ndarray, torch.Tensor, warp.types.array]] = None, angular_velocities: Optional[Union[numpy.ndarray, torch.Tensor, warp.types.array]] = None, indices: Optional[Union[numpy.ndarray, list, torch.Tensor, warp.types.array]] = None) None

Set the default state (position, orientation and linear and angular velocities) of prims in the view, that will be used after each reset.

Note

The default states will be set during post-reset (e.g., calling .post_reset() or world.reset() methods)

Parameters
  • positions (Optional[Union[np.ndarray, torch.Tensor, wp.array]], optional) – default positions in the world frame of the prim. shape is (M, 3).

  • orientations (Optional[Union[np.ndarray, torch.Tensor, wp.array]], optional) – default quaternion orientations in the world frame of the prims. quaternion is scalar-first (w, x, y, z). shape is (M, 4).

  • linear_velocities (Optional[Union[np.ndarray, torch.Tensor, wp.array]], optional) – default linear velocities of each prim in the view (to be applied in the first frame and on resets). Shape is (M, 3). Defaults to None.

  • angular_velocities (Optional[Union[np.ndarray, torch.Tensor, wp.array]], optional) – default angular velocities of each prim in the view (to be applied in the first frame and on resets). Shape is (M, 3). Defaults to None.

  • indices (Optional[Union[np.ndarray, list, torch.Tensor, wp.array]], optional) – indices to specify which prims to manipulate. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

Example:

>>> # configure default states for all prims
>>> positions = np.zeros((num_envs, 3))
>>> positions[:, 0] = np.arange(num_envs)
>>> orientations = np.tile(np.array([1.0, 0.0, 0.0, 0.0]), (num_envs, 1))
>>> linear_velocities = np.zeros((num_envs, 3))
>>> angular_velocities = np.zeros((num_envs, 3))
>>> prims.set_default_state(
...     positions=positions,
...     orientations=orientations,
...     linear_velocities=linear_velocities,
...     angular_velocities=angular_velocities
... )
>>>
>>> # set default states during post-reset
>>> prims.post_reset()
set_densities(densities: Optional[Union[numpy.ndarray, torch.Tensor, warp.types.array]], indices: Optional[Union[numpy.ndarray, list, torch.Tensor, warp.types.array]] = None) None

Set densities of prims in the view.

Parameters
  • densities (Optional[Union[np.ndarray, torch.Tensor, wp.array]]) – density in kg/m^3 specified for each prim in the view. shape is (M,). Defaults to None.

  • indices (Optional[Union[np.ndarray, list, torch.Tensor, wp.array]], optional) – indices to specify which prims to manipulate. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

Example:

>>> # set all rigid body densities to the specified values
>>> prims.set_densities(np.full(num_envs, 0.9))
>>>
>>> # set rigid body densities for the first, middle and last of the 5 envs
>>> prims.set_densities(np.full(3, 0.9), indices=np.array([0, 2, 4]))
set_inertias(values: Union[numpy.ndarray, torch.Tensor, warp.types.array], indices: Optional[Union[numpy.ndarray, List, torch.Tensor, warp.types.array]] = None) None

Set rigid body inertias for prims in the view.

Parameters
  • values (Union[np.ndarray, torch.Tensor, wp.array]) – body inertias for prims in the view. shape (M, 1, 9).

  • indices (Optional[Union[np.ndarray, List, torch.Tensor, wp.array]], optional) – indices to specify which prims to manipulate. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

Example:

>>> # set the rigid body inertias for all the rigid bodies to the specified values.
>>> # Since there are 5 envs, the inertias are repeated 5 times
>>> inertias = np.tile(np.array([0.1, 0.0, 0.0, 0.0, 0.1, 0.0, 0.0, 0.0, 0.1]), (num_envs, 1))
>>> prims.set_inertias(inertias)
>>>
>>> # set the rigid body inertias for the first, middle and last of the 5 envs
>>> inertias = np.tile(np.array([0.1, 0.0, 0.0, 0.0, 0.1, 0.0, 0.0, 0.0, 0.1]), (3, 1))
>>> prims.set_inertias(inertias, indices=np.array([0, 2, 4]))
set_linear_velocities(velocities: Optional[Union[numpy.ndarray, torch.Tensor, warp.types.array]], indices: Optional[Union[numpy.ndarray, list, torch.Tensor, warp.types.array]] = None)

Set the linear velocities of the prims in the view

The method does this through the PhysX API only. It has to be called after initialization. Note: This method is not supported for the gpu pipeline. set_velocities method should be used instead.

Warning

This method will immediately set the rigid prim state

Parameters
  • velocities (Optional[Union[np.ndarray, torch.Tensor, wp.array]]) – linear velocities to set the rigid prims to. shape is (M, 3).

  • indices (Optional[Union[np.ndarray, list, torch.Tensor, wp.array]], optional) – indices to specify which prims to manipulate. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

Hint

This method belongs to the methods used to set the rigid prim kinematic state:

set_velocities (set_linear_velocities, set_angular_velocities)

Example:

>>> # set each rigid prim linear velocity to (1.0, 1.0, 1.0)
>>> velocities = np.ones((num_envs, 3))
>>> prims.set_linear_velocities(velocities)
>>>
>>> # set only the rigid prim linear velocities for the first, middle and last of the 5 envs
>>> velocities = np.ones((3, 3))
>>> prims.set_linear_velocities(velocities, indices=np.array([0, 2, 4]))
set_local_poses(translations: Optional[Union[numpy.ndarray, torch.Tensor, warp.types.array]] = None, orientations: Optional[Union[numpy.ndarray, torch.Tensor, warp.types.array]] = None, indices: Optional[Union[numpy.ndarray, list, torch.Tensor, warp.types.array]] = None) None

Set prim poses in the view with respect to the local frame (the prim’s parent frame).

Parameters
  • translations (Optional[Union[np.ndarray, torch.Tensor, wp.array]], optional) – translations in the local frame of the prims (with respect to its parent prim). shape is (M, 3). Defaults to None, which means left unchanged.

  • orientations (Optional[Union[np.ndarray, torch.Tensor, wp.array]], optional) – quaternion orientations in the local frame of the prims. quaternion is scalar-first (w, x, y, z). shape is (M, 4). Defaults to None, which means left unchanged.

  • indices (Optional[Union[np.ndarray, list, torch.Tensor, wp.array]], optional) – indices to specify which prims to manipulate. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

Example:

>>> # reposition all rigid prims
>>> positions = np.zeros((num_envs, 3))
>>> positions[:,0] = np.arange(num_envs)
>>> orientations = np.tile(np.array([1.0, 0.0, 0.0, 0.0]), (num_envs, 1))
>>> prims.set_local_poses(positions, orientations)
>>>
>>> # reposition only the rigid prims for the first, middle and last of the 5 envs
>>> positions = np.zeros((3, 3))
>>> positions[:,1] = np.arange(3)
>>> orientations = np.tile(np.array([1.0, 0.0, 0.0, 0.0]), (3, 1))
>>> prims.set_local_poses(positions, orientations, indices=np.array([0, 2, 4]))
set_local_scales(scales: Optional[Union[numpy.ndarray, torch.Tensor, warp.types.array]], indices: Optional[Union[numpy.ndarray, list, torch.Tensor, warp.types.array]] = None) None

Set prim scales in the view with respect to the local frame (the prim’s parent frame)

Parameters
  • scales (Optional[Union[np.ndarray, torch.Tensor, wp.array]]) – scales to be applied to the prim’s dimensions in the view. shape is (M, 3).

  • indices (Optional[Union[np.ndarray, list, torch.Tensor, wp.array]], optional) – indices to specify which prims to manipulate. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

Example:

>>> # set the scale for all prims. Since there are 5 envs, the scale is repeated 5 times
>>> scales = np.tile(np.array([1.0, 0.75, 0.5]), (num_envs, 1))
>>> prims.set_local_scales(scales)
>>>
>>> # set the scale for the first, middle and last of the 5 envs
>>> scales = np.tile(np.array([1.0, 0.75, 0.5]), (3, 1))
>>> prims.set_local_scales(scales, indices=np.array([0, 2, 4]))
set_masses(masses: Union[numpy.ndarray, torch.Tensor, warp.types.array], indices: Optional[Union[numpy.ndarray, List, torch.Tensor, warp.types.array]] = None) None

Set body masses for prims in the view.

Parameters
  • masses (Union[np.ndarray, torch.Tensor, wp.array]) – body masses for prims in kg. shape (M,).

  • indices (Optional[Union[np.ndarray, List, torch.Tensor, wp.array]], optional) – indices to specify which prims to manipulate. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

Example:

>>> # set the rigid body masses for all the rigid bodies to the indicated values.
>>> prims.set_masses(np.full(num_envs, 10.0))
>>>
>>> # set the rigid body masses for the first, middle and last of the 5 envs
>>> prims.set_masses(np.full(3, 10.0), indices=np.array([0, 2, 4]))
set_sleep_thresholds(thresholds: Optional[Union[numpy.ndarray, torch.Tensor, warp.types.array]], indices: Optional[Union[numpy.ndarray, list, torch.Tensor, warp.types.array]] = None) None

Set sleep thresholds of prims in the view.

Search for Rigid Body Dynamics > Sleeping in PhysX docs for more details

Parameters
  • thresholds (Optional[Union[np.ndarray, torch.Tensor, wp.array]]) – Mass-normalized kinetic energy threshold below which an actor may go to sleep. Range: [0, inf) Defaults: 0.00005 * tolerancesSpeed* tolerancesSpeed Units: distance^2 / second^2. shape (M,).

  • indices (Optional[Union[np.ndarray, list, torch.Tensor, wp.array]], optional) – indices to specify which prims to manipulate. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

Example:

>>> # set all rigid body densities to the specified values
>>> prims.set_sleep_thresholds(np.full(num_envs, 1e-5))
>>>
>>> # set rigid body densities for the first, middle and last of the 5 envs
>>> prims.set_sleep_thresholds(np.full(3, 1e-5), indices=np.array([0, 2, 4]))
set_velocities(velocities: Union[numpy.ndarray, torch.Tensor, warp.types.array], indices: Optional[Union[numpy.ndarray, list, torch.Tensor, warp.types.array]] = None) None

Set the linear and angular velocities of the prims in the view at once.

The method does this through the PhysX API only. It has to be called after initialization

Warning

This method will immediately set the rigid prim state

Parameters
  • velocities (Optional[Union[np.ndarray, torch.Tensor, wp.array]]) – linear and angular velocities respectively to set the rigid prims to. shape is (M, 6).

  • indices (Optional[Union[np.ndarray, list, torch.Tensor, wp.array]], optional) – indices to specify which prims to manipulate. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

Hint

This method belongs to the methods used to set the rigid prim kinematic state:

set_velocities (set_linear_velocities, set_angular_velocities)

Example:

>>> # set each rigid prim linear velocity to (1., 1., 1.) and angular velocity to (5., 5., 5.)
>>> velocities = np.ones((num_envs, 6))
>>> velocities[:,3:] = 5.0
>>> prims.set_velocities(velocities)
>>>
>>> # set only the rigid prim velocities for the first, middle and last of the 5 envs
>>> velocities = np.ones((3, 6))
>>> velocities[:,3:] = 5.0
>>> prims.set_velocities(velocities, indices=np.array([0, 2, 4]))
set_visibilities(visibilities: Union[numpy.ndarray, torch.Tensor, warp.types.array], indices: Optional[Union[numpy.ndarray, list, torch.Tensor, warp.types.array]] = None) None

Set the visibilities of the prims in stage

Parameters
  • visibilities (Union[np.ndarray, torch.Tensor, wp.array]) – flag to set the visibilities of the usd prims in stage. Shape (M,). Where M <= size of the encapsulated prims in the view.

  • indices (Optional[Union[np.ndarray, list, torch.Tensor, wp.array]], optional) – indices to specify which prims to manipulate. Shape (M,). Defaults to None (i.e: all prims in the view).

Example:

>>> # make all prims not visible in the stage
>>> prims.set_visibilities(visibilities=[False] * num_envs)
set_world_poses(positions: Optional[Union[numpy.ndarray, torch.Tensor, warp.types.array]] = None, orientations: Optional[Union[numpy.ndarray, torch.Tensor, warp.types.array]] = None, indices: Optional[Union[numpy.ndarray, list, torch.Tensor, warp.types.array]] = None) None

Set poses of prims in the view with respect to the world’s frame.

Warning

This method will change (teleport) the prim poses immediately to the specified value

Parameters
  • positions (Optional[Union[np.ndarray, torch.Tensor, wp.array]], optional) – positions in the world frame of the prim. shape is (M, 3). Defaults to None, which means left unchanged.

  • orientations (Optional[Union[np.ndarray, torch.Tensor, wp.array]], optional) – quaternion orientations in the world frame of the prims. quaternion is scalar-first (w, x, y, z). shape is (M, 4). Defaults to None, which means left unchanged.

  • indices (Optional[Union[np.ndarray, list, torch.Tensor, wp.array]], optional) – indices to specify which prims to manipulate. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

Hint

This method belongs to the methods used to set the prim state

Example:

>>> # reposition all rigid prims in row (x-axis)
>>> positions = np.zeros((num_envs, 3))
>>> positions[:,0] = np.arange(num_envs)
>>> orientations = np.tile(np.array([1.0, 0.0, 0.0, 0.0]), (num_envs, 1))
>>> prims.set_world_poses(positions, orientations)
>>>
>>> # reposition only the rigid prims for the first, middle and last of the 5 envs in column (y-axis)
>>> positions = np.zeros((3, 3))
>>> positions[:,1] = np.arange(3)
>>> orientations = np.tile(np.array([1.0, 0.0, 0.0, 0.0]), (3, 1))
>>> prims.set_world_poses(positions, orientations, indices=np.array([0, 2, 4]))

Rigid Contact View

class RigidContactView(prim_paths_expr: str, filter_paths_expr: List[str], name: str = 'rigid_contact_view', prepare_contact_sensors: bool = True, disable_stablization: bool = True, max_contact_count: int = 0)

Provides high level functions to deal with rigid prims (one or many) that track their contacts through filters as well as their attributes/properties.

This class wraps all matching rigid prims found at the regex provided at the prim_paths_expr argument

Warning

The rigid prim view object must be initialized in order to be able to operate on it. See the initialize method for more details.

Parameters
  • prim_paths_expr (str) – prim paths regex to encapsulate all prims that match it. example: “/World/Env[1-5]/Cube” will match /World/Env1/Cube, /World/Env2/Cube..etc. (a non regex prim path can also be used to encapsulate one rigid prim).

  • name (str, optional) – shortname to be used as a key by Scene class. Note: needs to be unique if the object is added to the Scene. Defaults to “rigid_contact_view”.

  • prepare_contact_sensors (bool, Optional) – if rigid prims in the view are not cloned from a prim in a prepared state, (although slow for large number of prims) this ensures that appropriate physics settings are applied on all the prim in the view.

  • disable_stablization (bool, optional) – disables the contact stabilization parameter in the physics context

  • max_contact_count (int, optional) – maximum number of contact data to report when detailed contact information is needed

Example:

>>> import omni.isaac.core.utils.stage as stage_utils
>>> from omni.isaac.cloner import GridCloner
>>> from omni.isaac.core.prims import RigidContactView
>>> from pxr import UsdGeom
>>>
>>> env_zero_path = "/World/envs/env_0"
>>> num_envs = 5
>>>
>>> # clone the environment (num_envs)
>>> cloner = GridCloner(spacing=0)
>>> cloner.define_base_env(env_zero_path)
>>> UsdGeom.Xform.Define(stage_utils.get_current_stage(), env_zero_path)
>>> stage_utils.get_current_stage().DefinePrim(f"{env_zero_path}/Xform", "Xform")
>>> stage_utils.get_current_stage().DefinePrim(f"{env_zero_path}/Xform/Cube", "Cube")
>>> # position the cubes on top of each other
>>> position_offsets = np.zeros((num_envs, 3))
>>> position_offsets[:, 2] = np.arange(num_envs) * 1.1
>>> env_pos = cloner.clone(
...     source_prim_path=env_zero_path,
...     prim_paths=cloner.generate_paths("/World/envs/env", num_envs),
...     position_offsets=position_offsets
...     copy_from_source=True,
... )
>>>
>>> # wrap the prims
>>> prims = RigidContactView(
...     prim_paths_expr="/World/envs/env.*/Xform",
...     name="RigidContactView_view",
...     filter_paths_expr=["/World/envs/env_2/Xform"],
...     max_contact_count=10,
... )
>>> prims
<omni.isaac.core.prims.rigid_contact_view.RigidContactView object at 0x7f8d4eb1abf0>
get_contact_force_data(indices: Optional[Union[numpy.ndarray, list, torch.Tensor, warp.types.array]] = None, clone: bool = True, dt: float = 1.0) Tuple[Union[numpy.ndarray, torch.Tensor, warp.types.indexedarray], Union[numpy.ndarray, torch.Tensor, warp.types.indexedarray], Union[numpy.ndarray, torch.Tensor, warp.types.indexedarray], Union[numpy.ndarray, torch.Tensor, warp.types.indexedarray], Union[numpy.ndarray, torch.Tensor, warp.types.indexedarray], Union[numpy.ndarray, torch.Tensor, warp.types.indexedarray]]

Get more detailed contact information between the prims in the view and the filter prims.

Specifically, this method provides individual contact normals, contact points, contact separations as well as contact forces for each pair (the sum of which equals the forces that the get_contact_force_matrix method provides as the force aggregate of a pair)

Given to the dynamic nature of collision between bodies, this method will provide buffers of contact data which are arranged sequentially for each pair. The starting index and the number of contact data points for each pair in this stream can be realized from pair_contacts_start_indices, and pair_contacts_count tensors. They both have a dimension of (num_shapes, num_filters) where num_filters is determined according to the filter_paths_expr parameter

Parameters
  • indices (Optional[Union[np.ndarray, list, torch.Tensor, wp.array]], optional) – indices to specify which prims to query. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

  • clone (bool, optional) – True to return a clone of the internal buffer. Otherwise False. Defaults to True.

  • dt (float) – time step multiplier to convert the underlying impulses to forces. If the default value is used then the forces are in fact contact impulses

Returns

Tuple[Union[np.ndarray, torch.Tensor, wp.indexedarray], Union[np.ndarray, torch.Tensor, wp.indexedarray], Union[np.ndarray, torch.Tensor, wp.indexedarray], Union[np.ndarray, torch.Tensor, wp.indexedarray], Union[np.ndarray, torch.Tensor, wp.indexedarray], Union[np.ndarray, torch.Tensor, wp.indexedarray]]: A set of buffers for normal forces with shape (max_contact_count, 1), points with shape (max_contact_count, 3), normals with shape (max_contact_count, 3), and distances with shape (max_contact_count, 1), as well as two tensors with shape (M, self.num_filters) to indicate the starting index and the number of contact data points per pair in the aforementioned buffers.

Example:

>>> # get detailed contact force data between the prims and the filter prims (the cube in the middle)
>>> data = prims.get_contact_force_data()
>>> data[0]  # normal forces
[[-168.53815]
 [ -89.57392]
 [-156.10307]
 [ -75.17234]
 [  98.0681 ]
 [  52.56319]
 [ 108.26558]
 [  67.62025]
 [   0.     ]
 [   0.     ]]
>>> data[1]  # points
[[ 0.4948182  -0.49902824  1.5001888 ]
 [ 0.4950411   0.49933064  1.5001996 ]
 [-0.5024581   0.49930018  1.5001924 ]
 [-0.5024276  -0.49880558  1.5001817 ]
 [-0.5023767   0.497138    2.5001519 ]
 [-0.502735   -0.49877006  2.5001822 ]
 [ 0.4947694  -0.4989927   2.500226  ]
 [ 0.4949917   0.49677914  2.5001955 ]
 [ 0.          0.          0.        ]
 [ 0.          0.          0.        ]]
>>> data[2]  # normals
[[-4.3812128e-05  3.0501858e-05  1.0000000e+00]
 [-4.3812128e-05  3.0501858e-05  1.0000000e+00]
 [-4.3812128e-05  3.0501858e-05  1.0000000e+00]
 [-4.3812128e-05  3.0501858e-05  1.0000000e+00]
 [ 2.1408198e-06 -7.0731985e-05  1.0000000e+00]
 [ 2.1408198e-06 -7.0731985e-05  1.0000000e+00]
 [ 2.1408198e-06 -7.0731985e-05  1.0000000e+00]
 [ 2.1408198e-06 -7.0731985e-05  1.0000000e+00]
 [ 0.0000000e+00  0.0000000e+00  0.0000000e+00]
 [ 0.0000000e+00  0.0000000e+00  0.0000000e+00]]
>>> data[3]  # distances
[[ 3.7143487e-05]
 [-4.0254322e-06]
 [-4.0531158e-05]
 [ 6.0737699e-07]
 [ 1.9307560e-04]
 [ 9.2272363e-05]
 [ 4.6372414e-05]
 [ 1.4718286e-04]
 [ 0.0000000e+00]
 [ 0.0000000e+00]]
>>> data[4]  # pair contacts count
[[0]
 [4]
 [0]
 [4]
 [0]]
>>> data[5]  # start indices of pair contacts
[[0]
 [0]
 [4]
 [4]
 [8]]
get_contact_force_matrix(indices: Optional[Union[numpy.ndarray, list, torch.Tensor, warp.types.array]] = None, clone: bool = True, dt: float = 1.0) Union[numpy.ndarray, torch.Tensor, warp.types.indexedarray]

Get the contact forces between the prims in the view and the filter prims.

E.g., a matrix of dimension (num_shapes, num_filters, 3) where num_filters is determined according to the filter_paths_expr parameter

Parameters
  • indices (Optional[Union[np.ndarray, list, torch.Tensor, wp.array]], optional) – indices to specify which prims to query. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

  • clone (bool, optional) – True to return a clone of the internal buffer. Otherwise False. Defaults to True.

  • dt (float) – time step multiplier to convert the underlying impulses to forces. The function returns contact impulses if the default dt is used

Returns

Net contact forces between the view prim and the filter prims with shape (M, self.num_filters, 3).

Return type

Union[np.ndarray, torch.Tensor, wp.indexedarray]

Example:

>>> # get the contact forces between the prims and the filter prims (the cube in the middle)
>>> prims.get_contact_force_matrix()
[[[ 0.0000000e+00  0.0000000e+00  0.0000000e+00]]
 [[ 2.2649009e-02 -1.3710857e-02 -4.9047806e+02]]
 [[ 0.0000000e+00  0.0000000e+00  0.0000000e+00]]
 [[-3.3276828e-03 -2.3870371e-02  3.2733777e+02]]
 [[ 0.0000000e+00  0.0000000e+00  0.0000000e+00]]]
get_net_contact_forces(indices: Optional[Union[numpy.ndarray, torch.Tensor, warp.types.array]] = None, clone: bool = True, dt: float = 1.0) Union[numpy.ndarray, torch.Tensor, warp.types.indexedarray]

Get the overall net contact forces on the prims in the view with respect to the world’s frame.

Parameters
  • indices (Optional[Union[np.ndarray, list, torch.Tensor, wp.array]], optional) – indices to specify which prims to query. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

  • clone (bool, optional) – True to return a clone of the internal buffer. Otherwise False. Defaults to True.

  • dt (float) – time step multiplier to convert the underlying impulses to forces. The function returns contact impulses if the default dt is used

Returns

Net contact forces of the prims with shape (M,3).

Return type

Union[np.ndarray, torch.Tensor, wp.indexedarray]

Example:

>>> # get the net contact force on all rigid bodies. Returned shape is (5, 3).
>>> prims.get_net_contact_forces()
[[ 1.8731881e-03  5.4876995e-03  1.6408131e+02]
 [ 1.9060407e-02 -2.2513291e-02  1.6358723e+02]
 [-2.1011427e-02  3.5647806e-02  1.6371542e+02]
 [ 9.4006478e-05 -9.3258200e-03  1.6348369e+02]
 [ 9.3709816e-05 -9.2963902e-03  1.6296776e+02]]
>>>
>>> # get the net contact force on the rigid bodies for the first, middle and last of the 5 envs
>>> prims.get_net_contact_forces(indices=np.array([0, 2, 4]))
[[ 1.8731881e-03  5.4876995e-03  1.6408131e+02]
 [-2.1011427e-02  3.5647806e-02  1.6371542e+02]
 [ 9.3709816e-05 -9.2963902e-03  1.6296776e+02]]
initialize(physics_sim_view: Optional[omni.physics.tensors.bindings._physicsTensors.SimulationView] = None) None

Create a physics simulation view if not passed and set other properties using the PhysX tensor API

Note

If the rigid prim view has been added to the world scene (e.g., world.scene.add(prims)), it will be automatically initialized when the world is reset (e.g., world.reset()).

Warning

This method needs to be called after each hard reset (e.g., Stop + Play on the timeline) before interacting with any other class method.

Parameters

physics_sim_view (omni.physics.tensors.SimulationView, optional) – current physics simulation view. Defaults to None.

Example:

>>> prims.initialize()
is_physics_handle_valid() bool

Check if rigid prim view’s physics handler is initialized

Warning

If the physics handler is not valid many of the methods that requires PhysX will return None.

Returns

True if the physics handle of the view is valid (i.e physics is initialized for the view). Otherwise False.

Return type

bool

Example:

>>> prims.is_physics_handle_valid()
True
property num_filters: int
Returns

number of filters bodies that report their contact with the rigid prims.

Return type

int

Example:

>>> prims.num_filters
1
property num_shapes: int
Returns

number of rigid shapes for the prims in the view.

Return type

int

Example:

>>> prims.num_shapes
5

Cloth Prim

class ClothPrim(prim_path: str, particle_system: omni.isaac.core.prims.soft.particle_system.ParticleSystem, particle_material: Optional[omni.isaac.core.materials.particle_material.ParticleMaterial] = None, name: Optional[str] = 'cloth', position: Optional[Sequence[float]] = None, orientation: Optional[Sequence[float]] = None, scale: Optional[Sequence[float]] = None, visible: Optional[bool] = None, particle_mass: Optional[float] = 0.01, pressure: Optional[float] = None, particle_group: Optional[int] = 0, self_collision: Optional[bool] = True, self_collision_filter: Optional[bool] = True, stretch_stiffness: Optional[float] = None, bend_stiffness: Optional[float] = None, shear_stiffness: Optional[float] = None, spring_damping: Optional[float] = None)

Cloth primitive object provide functionalities to create and control cloth parameters

apply_visual_material(visual_material: omni.isaac.core.materials.visual_material.VisualMaterial, weaker_than_descendants: bool = False) None

Apply visual material to the held prim and optionally its descendants.

Parameters
  • visual_material (VisualMaterial) – visual material to be applied to the held prim. Currently supports PreviewSurface, OmniPBR and OmniGlass.

  • weaker_than_descendants (bool, optional) – True if the material shouldn’t override the descendants materials, otherwise False. Defaults to False.

Example:

>>> from omni.isaac.core.materials import OmniGlass
>>>
>>> # create a dark-red glass visual material
>>> material = OmniGlass(
...     prim_path="/World/material/glass",  # path to the material prim to create
...     ior=1.25,
...     depth=0.001,
...     thin_walled=False,
...     color=np.array([0.5, 0.0, 0.0])
... )
>>> prim.apply_visual_material(material)
get_applied_visual_material() omni.isaac.core.materials.visual_material.VisualMaterial

Return the current applied visual material in case it was applied using apply_visual_material or it’s one of the following materials that was already applied before: PreviewSurface, OmniPBR and OmniGlass.

Returns

the current applied visual material if its type is currently supported.

Return type

VisualMaterial

Example:

>>> # given a visual material applied
>>> prim.get_applied_visual_material()
<omni.isaac.core.materials.omni_glass.OmniGlass object at 0x7f36263106a0>
get_cloth_bend_stiffness() float

Reports a single value that would be used to generate the stiffnesses. This API does not report the actually created stiffnesses.

Returns

The bend stiffness.

Return type

float

get_cloth_damping() Union[numpy.ndarray, torch.Tensor]

Reports a single value that would be used to generate the dampings. This API does not report the actually created dampings.

Returns

The spring damping.

Return type

float

get_cloth_shear_stiffness() float

Reports a single value that would be used to generate the stiffnesses. This API does not report the actually created stiffnesses.

Returns

The shear stiffness.

Return type

float

get_cloth_stretch_stiffness() float

Reports a single value that would be used to generate the stiffnesses. This API does not report the actually created stiffnesses.

Returns

The stretch stiffness.

Return type

float

get_current_dynamic_state() omni.isaac.core.utils.types.DynamicState

Return the DynamicState that contains the position and orientation of the cloth prim

Returns

position (np.ndarray, optional):

position in the world frame of the prim. shape is (3, ). Defaults to None, which means left unchanged.

orientation (np.ndarray, optional):

quaternion orientation in the world frame of the prim. quaternion is scalar-first (w, x, y, z). shape is (4, ). Defaults to None, which means left unchanged.

Return type

DynamicState

get_default_state() omni.isaac.core.utils.types.XFormPrimState

Get the default prim states (spatial position and orientation).

Returns

an object that contains the default state of the prim (position and orientation)

Return type

XFormPrimState

Example:

>>> state = prim.get_default_state()
>>> state
<omni.isaac.core.utils.types.XFormPrimState object at 0x7f33addda650>
>>>
>>> state.position
[-4.5299529e-08 -1.8347054e-09 -2.8610229e-08]
>>> state.orientation
[1. 0. 0. 0.]
get_local_pose() Tuple[numpy.ndarray, numpy.ndarray]

Get prim’s pose with respect to the local frame (the prim’s parent frame)

Returns

first index is the position in the local frame (with shape (3, )). Second index is quaternion orientation (with shape (4, )) in the local frame

Return type

Tuple[np.ndarray, np.ndarray]

Example:

>>> # if the prim is in position (1.0, 0.5, 0.0) with respect to the world frame
>>> position, orientation = prim.get_local_pose()
>>> position
[0. 0. 0.]
>>> orientation
[0. 0. 0.]
get_local_scale() numpy.ndarray

Get prim’s scale with respect to the local frame (the parent’s frame)

Returns

scale applied to the prim’s dimensions in the local frame. shape is (3, ).

Return type

np.ndarray

Example:

>>> prim.get_local_scale()
[1. 1. 1.]
get_particle_group() int
Returns

self collision.

Return type

bool

get_pressure() float
Returns

pressure value.

Return type

float

get_self_collision() bool
Returns

self collision.

Return type

bool

get_self_collision_filter() bool
Returns

self collision filter.

Return type

bool

get_spring_damping() Union[numpy.ndarray, torch.Tensor]

Gets damping values of spring constraints

Returns

The spring damping.

Return type

Union[np.ndarray, torch.Tensor]

get_stretch_stiffness() Union[numpy.ndarray, torch.Tensor]

Gets stretch stiffness values of spring constraints

Returns

The stretch stiffness.

Return type

float

get_visibility() bool
Returns

true if the prim is visible in stage. false otherwise.

Return type

bool

Example:

>>> # get the visible state of an visible prim on the stage
>>> prim.get_visibility()
True
get_world_pose() Tuple[numpy.ndarray, numpy.ndarray]

Get prim’s pose with respect to the world’s frame

Returns

first index is the position in the world frame (with shape (3, )). Second index is quaternion orientation (with shape (4, )) in the world frame

Return type

Tuple[np.ndarray, np.ndarray]

Example:

>>> # if the prim is in position (1.0, 0.5, 0.0) with respect to the world frame
>>> position, orientation = prim.get_world_pose()
>>> position
[1.  0.5 0. ]
>>> orientation
[1. 0. 0. 0.]
get_world_scale() numpy.ndarray

Get prim’s scale with respect to the world’s frame

Returns

scale applied to the prim’s dimensions in the world frame. shape is (3, ).

Return type

np.ndarray

Example:

>>> prim.get_world_scale()
[1. 1. 1.]
initialize(physics_sim_view=None) None

Create a physics simulation view if not passed and using PhysX tensor API

Note

If the prim has been added to the world scene (e.g., world.scene.add(prim)), it will be automatically initialized when the world is reset (e.g., world.reset()).

Parameters

physics_sim_view (omni.physics.tensors.SimulationView, optional) – current physics simulation view. Defaults to None.

Example:

>>> prim.initialize()
is_valid() bool

Check if the prim path has a valid USD Prim at it

Returns

True is the current prim path corresponds to a valid prim in stage. False otherwise.

Return type

bool

Example:

>>> # given an existing and valid prim
>>> prims.is_valid()
True
is_visual_material_applied() bool

Check if there is a visual material applied

Returns

True if there is a visual material applied. False otherwise.

Return type

bool

Example:

>>> # given a visual material applied
>>> prim.is_visual_material_applied()
True
property mesh: pxr.UsdGeom.Mesh

Returns: Usd.Prim: USD Prim object that this object tracks.

property name: Optional[str]

Returns: str: name given to the prim when instantiating it. Otherwise None.

Used to query if the prim is a non root articulation link

Returns

True if the prim itself is a non root link

Return type

bool

Example:

>>> # for a wrapped articulation (where the root prim has the Physics Articulation Root property applied)
>>> prim.non_root_articulation_link
False
post_reset() None

Reset the prim to its default state (position and orientation).

Note

For an articulation, in addition to configuring the root prim’s default position and spatial orientation (defined via the set_default_state method), the joint’s positions, velocities, and efforts (defined via the set_joints_default_state method) are imposed

Example:

>>> prim.post_reset()
property prim: pxr.Usd.Prim

Returns: Usd.Prim: USD Prim object that this object holds.

property prim_path: str

Returns: str: prim path in the stage

set_cloth_bend_stiffness(stiffness: float) None

Sets a single bend stiffness value to all springs constraints in the cloth

Parameters

stiffness (float) – The cloth springs bend stiffness value. Range: [0 , inf), Units: force/distance = mass/second/second

set_cloth_damping(damping: float) None

Sets a single damping value to all springs constraints in the cloth

Parameters

damping (float) – The cloth springs damping value. Range: [0 , inf), Units: force/velocity = mass/second

set_cloth_shear_stiffness(stiffness: float) None

Sets a single shear stiffness value to all springs constraints in the cloth

Parameters

stiffness (float) – The cloth springs shear stiffness value. Range: [0 , inf), Units: force/distance = mass/second/second

set_cloth_stretch_stiffness(stiffness: Union[numpy.ndarray, torch.Tensor]) None

Sets a single stretch stiffness value to all springs constraints in the cloth

Parameters

stiffness (Union[np.ndarray, torch.Tensor]) – The cloth springs stretch stiffness value. Range: [0 , inf), Units: force/distance = mass/second/second

set_default_state(position: Optional[Sequence[float]] = None, orientation: Optional[Sequence[float]] = None) None

Set the default state of the prim (position and orientation), that will be used after each reset.

Parameters
  • position (Optional[Sequence[float]], optional) – position in the world frame of the prim. shape is (3, ). Defaults to None, which means left unchanged.

  • orientation (Optional[Sequence[float]], optional) – quaternion orientation in the world frame of the prim. quaternion is scalar-first (w, x, y, z). shape is (4, ). Defaults to None, which means left unchanged.

Example:

>>> # configure default state
>>> prim.set_default_state(position=np.array([1.0, 0.5, 0.0]), orientation=np.array([1, 0, 0, 0]))
>>>
>>> # set default states during post-reset
>>> prim.post_reset()
set_local_pose(translation: Optional[Sequence[float]] = None, orientation: Optional[Sequence[float]] = None) None

Set prim’s pose with respect to the local frame (the prim’s parent frame).

Warning

This method will change (teleport) the prim pose immediately to the indicated value

Parameters
  • translation (Optional[Sequence[float]], optional) – translation in the local frame of the prim (with respect to its parent prim). shape is (3, ). Defaults to None, which means left unchanged.

  • orientation (Optional[Sequence[float]], optional) – quaternion orientation in the local frame of the prim. quaternion is scalar-first (w, x, y, z). shape is (4, ). Defaults to None, which means left unchanged.

Hint

This method belongs to the methods used to set the prim state

Example:

>>> prim.set_local_pose(translation=np.array([1.0, 0.5, 0.0]), orientation=np.array([1., 0., 0., 0.]))
set_local_scale(scale: Optional[Sequence[float]]) None

Set prim’s scale with respect to the local frame (the prim’s parent frame).

Parameters

scale (Optional[Sequence[float]]) – scale to be applied to the prim’s dimensions. shape is (3, ). Defaults to None, which means left unchanged.

Example:

>>> # scale prim 10 times smaller
>>> prim.set_local_scale(np.array([0.1, 0.1, 0.1]))
set_particle_group(particle_group: int) None
Parameters

particle_group (int) – particle group.

set_pressure(pressure: float) None
Parameters

pressure (float) – pressure value.

set_self_collision(self_collision: bool) None
Parameters

self_collision (bool) – self collision.

set_self_collision_filter(self_collision_filter: bool) None
Parameters

self_collision_filter (bool) – self collision filter.

set_spring_damping(damping: Union[numpy.ndarray, torch.Tensor]) None

Sets damping values of spring constraints in the cloth

Parameters

damping (List[float]) – The damping values of springs. Range: [0 , inf), Units: force/distance = mass/second

set_stretch_stiffness(stiffness: Union[numpy.ndarray, torch.Tensor]) None

Sets stretch stiffness values of spring constraints in the cloth It represents a stiffness for linear springs placed between particles to counteract stretching.

Parameters

stiffness (Union[np.ndarray, torch.Tensor]) – The stretch stiffnesses. Range: [0 , inf), Units: force/distance = mass/second/second

set_visibility(visible: bool) None

Set the visibility of the prim in stage

Parameters

visible (bool) – flag to set the visibility of the usd prim in stage.

Example:

>>> # make prim not visible in the stage
>>> prim.set_visibility(visible=False)
set_world_pose(position: Optional[Sequence[float]] = None, orientation: Optional[Sequence[float]] = None) None

Ses prim’s pose with respect to the world’s frame

Warning

This method will change (teleport) the prim pose immediately to the indicated value

Parameters
  • position (Optional[Sequence[float]], optional) – position in the world frame of the prim. shape is (3, ). Defaults to None, which means left unchanged.

  • orientation (Optional[Sequence[float]], optional) – quaternion orientation in the world frame of the prim. quaternion is scalar-first (w, x, y, z). shape is (4, ). Defaults to None, which means left unchanged.

Hint

This method belongs to the methods used to set the prim state

Example:

>>> prim.set_world_pose(position=np.array([1.0, 0.5, 0.0]), orientation=np.array([1., 0., 0., 0.]))

Cloth Prim View

class ClothPrimView(prim_paths_expr: str, particle_systems: Optional[Union[numpy.ndarray, torch.Tensor]] = None, particle_materials: Optional[Union[numpy.ndarray, torch.Tensor]] = None, name: str = 'cloth_prim_view', reset_xform_properties: bool = True, positions: Optional[Union[numpy.ndarray, torch.Tensor]] = None, translations: Optional[Union[numpy.ndarray, torch.Tensor]] = None, orientations: Optional[Union[numpy.ndarray, torch.Tensor]] = None, scales: Optional[Union[numpy.ndarray, torch.Tensor]] = None, visibilities: Optional[Union[numpy.ndarray, torch.Tensor]] = None, particle_masses: Optional[Union[numpy.ndarray, torch.Tensor]] = None, pressures: Optional[Union[numpy.ndarray, torch.Tensor]] = None, particle_groups: Optional[Union[numpy.ndarray, torch.Tensor]] = None, self_collisions: Optional[Union[numpy.ndarray, torch.Tensor]] = None, self_collision_filters: Optional[Union[numpy.ndarray, torch.Tensor]] = None, stretch_stiffnesses: Optional[Union[numpy.ndarray, torch.Tensor]] = None, bend_stiffnesses: Optional[Union[numpy.ndarray, torch.Tensor]] = None, shear_stiffnesses: Optional[Union[numpy.ndarray, torch.Tensor]] = None, spring_dampings: Optional[Union[numpy.ndarray, torch.Tensor]] = None)

The view class for cloth prims.

apply_visual_materials(visual_materials: Union[omni.isaac.core.materials.visual_material.VisualMaterial, List[omni.isaac.core.materials.visual_material.VisualMaterial]], weaker_than_descendants: Optional[Union[bool, List[bool]]] = None, indices: Optional[Union[numpy.ndarray, list, torch.Tensor, warp.types.array]] = None) None

Apply visual material to the prims and optionally their prim descendants.

Parameters
  • visual_materials (Union[VisualMaterial, List[VisualMaterial]]) – visual materials to be applied to the prims. Currently supports PreviewSurface, OmniPBR and OmniGlass. If a list is provided then its size has to be equal the view’s size or indices size. If one material is provided it will be applied to all prims in the view.

  • weaker_than_descendants (Optional[Union[bool, List[bool]]], optional) – True if the material shouldn’t override the descendants materials, otherwise False. Defaults to False. If a list of visual materials is provided then a list has to be provided with the same size for this arg as well.

  • indices (Optional[Union[np.ndarray, list, torch.Tensor, wp.array]], optional) – indices to specify which prims to manipulate. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

Raises
  • Exception – length of visual materials != length of prims indexed

  • Exception – length of visual materials != length of weaker descendants bools arg

Example:

>>> from omni.isaac.core.materials import OmniGlass
>>>
>>> # create a dark-red glass visual material
>>> material = OmniGlass(
...     prim_path="/World/material/glass",  # path to the material prim to create
...     ior=1.25,
...     depth=0.001,
...     thin_walled=False,
...     color=np.array([0.5, 0.0, 0.0])
... )
>>> prims.apply_visual_materials(material)
property count: int

Returns: int: cloth counts.

get_applied_visual_materials(indices: Optional[Union[numpy.ndarray, list, torch.Tensor, warp.types.array]] = None) List[omni.isaac.core.materials.visual_material.VisualMaterial]

Get the current applied visual materials

Parameters

indices (Optional[Union[np.ndarray, list, torch.Tensor, wp.array]], optional) – indices to specify which prims to query. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

Returns

a list of the current applied visual materials to the prims if its type is currently supported.

Return type

List[VisualMaterial]

Example:

>>> # get all applied visual materials. Returned size is 5 for the example: 5 envs
>>> prims.get_applied_visual_materials()
[<omni.isaac.core.materials.omni_glass.OmniGlass object at 0x7f829c165de0>,
 <omni.isaac.core.materials.omni_glass.OmniGlass object at 0x7f829c165de0>,
 <omni.isaac.core.materials.omni_glass.OmniGlass object at 0x7f829c165de0>,
 <omni.isaac.core.materials.omni_glass.OmniGlass object at 0x7f829c165de0>,
 <omni.isaac.core.materials.omni_glass.OmniGlass object at 0x7f829c165de0>]
>>>
>>> # get the applied visual materials for the first, middle and last of the 5 envs. Returned size is 3
>>> prims.get_applied_visual_materials(indices=np.array([0, 2, 4]))
[<omni.isaac.core.materials.omni_glass.OmniGlass object at 0x7f829c165de0>,
 <omni.isaac.core.materials.omni_glass.OmniGlass object at 0x7f829c165de0>,
 <omni.isaac.core.materials.omni_glass.OmniGlass object at 0x7f829c165de0>]
get_cloths_bend_stiffnesses(indices: Optional[Union[numpy.ndarray, list, torch.Tensor]] = None, clone: bool = True) Union[numpy.ndarray, torch.Tensor]

Gets the value of bend stiffness set to all the springs within cloths indicated by the indices.

Parameters
  • indices (Optional[Union[np.ndarray, list, torch.Tensor]], optional) – indices to specify which cloth prims to query. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

  • clone (bool, optional) – True to return a clone of the internal buffer. Otherwise False. Defaults to True.

Returns

bend stiffness tensor with shape (M, )

Return type

Union[Tuple[np.ndarray, np.ndarray], Tuple[torch.Tensor, torch.Tensor]]

get_cloths_dampings(indices: Optional[Union[numpy.ndarray, list, torch.Tensor]] = None, clone: bool = True) Union[numpy.ndarray, torch.Tensor]

Gets the value of damping set for all the springs within cloths indicated by the indices.

Parameters
  • indices (Optional[Union[np.ndarray, list, torch.Tensor]], optional) – indices to specify which cloth prims to query. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

  • clone (bool, optional) – True to return a clone of the internal buffer. Otherwise False. Defaults to True.

Returns

damping tensor with shape (M, )

Return type

Union[Tuple[np.ndarray, np.ndarray], Tuple[torch.Tensor, torch.Tensor]]

get_cloths_shear_stiffnesses(indices: Optional[Union[numpy.ndarray, list, torch.Tensor]] = None, clone: bool = True) Union[numpy.ndarray, torch.Tensor]

Gets the value of shear stiffness set to all the springs within cloths indicated by the indices.

Parameters
  • indices (Optional[Union[np.ndarray, list, torch.Tensor]], optional) – indices to specify which cloth prims to query. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

  • clone (bool, optional) – True to return a clone of the internal buffer. Otherwise False. Defaults to True.

Returns

shear stiffness tensor with shape (M, )

Return type

Union[Tuple[np.ndarray, np.ndarray], Tuple[torch.Tensor, torch.Tensor]]

get_cloths_stretch_stiffnesses(indices: Optional[Union[numpy.ndarray, list, torch.Tensor]] = None, clone: bool = True) Union[numpy.ndarray, torch.Tensor]

Gets the value of stretch stiffness set to all the springs within cloths indicated by the indices.

Parameters
  • indices (Optional[Union[np.ndarray, list, torch.Tensor]], optional) – indices to specify which cloth prims to query. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

  • clone (bool, optional) – True to return a clone of the internal buffer. Otherwise False. Defaults to True.

Returns

stretch stiffness tensor with shape (M, )

Return type

Union[Tuple[np.ndarray, np.ndarray], Tuple[torch.Tensor, torch.Tensor]]

get_default_state() omni.isaac.core.utils.types.XFormPrimViewState

Get the default states (positions and orientations) defined with the set_default_state method

Returns

returns the default state of the prims that is used after each reset.

Return type

XFormPrimViewState

Example:

>>> state = prims.get_default_state()
>>> state
<omni.isaac.core.utils.types.XFormPrimViewState object at 0x7f82f73e3070>
>>> state.positions
[[ 1.5  -0.75  0.  ]
 [ 1.5   0.75  0.  ]
 [ 0.   -0.75  0.  ]
 [ 0.    0.75  0.  ]
 [-1.5  -0.75  0.  ]]
>>> state.orientations
[[1. 0. 0. 0.]
 [1. 0. 0. 0.]
 [1. 0. 0. 0.]
 [1. 0. 0. 0.]
 [1. 0. 0. 0.]]
get_local_poses(indices: Optional[Union[numpy.ndarray, list, torch.Tensor, warp.types.array]] = None) Union[Tuple[numpy.ndarray, numpy.ndarray], Tuple[torch.Tensor, torch.Tensor], Tuple[warp.types.indexedarray, warp.types.indexedarray]]

Get prim poses in the view with respect to the local frame (the prim’s parent frame)

Parameters

indices (Optional[Union[np.ndarray, list, torch.Tensor, wp.array]], optional) – indices to specify which prims to query. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

Returns

first index is translations in the local frame of the prims. shape is (M, 3).

second index is quaternion orientations in the local frame of the prims. quaternion is scalar-first (w, x, y, z). shape is (M, 4).

Return type

Union[Tuple[np.ndarray, np.ndarray], Tuple[torch.Tensor, torch.Tensor], Tuple[wp.indexedarray, wp.indexedarray]]

Example:

>>> # get all prims poses with respect to the local frame.
>>> # Returned shape is position (5, 3) and orientation (5, 4) for the example: 5 envs
>>> positions, orientations = prims.get_local_poses()
>>> positions
[[ 1.5  -0.75  0.  ]
 [ 1.5   0.75  0.  ]
 [ 0.   -0.75  0.  ]
 [ 0.    0.75  0.  ]
 [-1.5  -0.75  0.  ]]
>>> orientations
[[1. 0. 0. 0.]
 [1. 0. 0. 0.]
 [1. 0. 0. 0.]
 [1. 0. 0. 0.]
 [1. 0. 0. 0.]]
>>>
>>> # get only the prims poses with respect to the local frame for the first, middle and last of the 5 envs.
>>> # Returned shape is position (3, 3) and orientation (3, 4) for the example: 3 envs selected
>>> positions, orientations = prims.get_local_poses(indices=np.array([0, 2, 4]))
>>> positions
[[ 1.5  -0.75  0.  ]
 [ 0.   -0.75  0.  ]
 [-1.5  -0.75  0.  ]]
>>> orientations
[[1. 0. 0. 0.]
 [1. 0. 0. 0.]
 [1. 0. 0. 0.]]
get_local_scales(indices: Optional[Union[numpy.ndarray, list, torch.Tensor, warp.types.array]] = None) Union[numpy.ndarray, torch.Tensor, warp.types.indexedarray]

Get prim scales in the view with respect to the local frame (the parent’s frame).

Parameters

indices (Optional[Union[np.ndarray, list, torch.Tensor, wp.array]], optional) – indices to specify which prims to query. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

Returns

scales applied to the prim’s dimensions in the local frame. shape is (M, 3).

Return type

Union[np.ndarray, torch.Tensor, wp.indexedarray]

Example:

>>> # get all prims scales with respect to the local frame.
>>> # Returned shape is (5, 3) for the example: 5 envs
>>> prims.get_local_scales()
[[1. 1. 1.]
 [1. 1. 1.]
 [1. 1. 1.]
 [1. 1. 1.]
 [1. 1. 1.]]
>>>
>>> # get only the prims scales with respect to the local frame for the first, middle and last of the 5 envs.
>>> # Returned shape is (3, 3) for the example: 3 envs selected
>>> prims.get_local_scales(indices=np.array([0, 2, 4]))
[[1. 1. 1.]
 [1. 1. 1.]
 [1. 1. 1.]]
get_particle_groups(indices: Optional[Union[numpy.ndarray, list, torch.Tensor]] = None, clone: bool = True) Union[numpy.ndarray, torch.Tensor]

Gets the particle groups of the cloths indicated by the indices.

Parameters
  • indices (Optional[Union[np.ndarray, list, torch.Tensor]], optional) – indices to specify which cloth prims to query. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

  • clone (bool, optional) – True to return a clone of the internal buffer. Otherwise False. Defaults to True.

Returns

particle groups with shape (M, ).

Return type

Union[Tuple[np.ndarray, np.ndarray], Tuple[torch.Tensor, torch.Tensor]]

get_particle_masses(indices: Optional[Union[numpy.ndarray, list, torch.Tensor]] = None, clone: bool = True) Union[numpy.ndarray, torch.Tensor]

Gets the particle masses for the cloths indicated by the indices.

Parameters
  • indices (Optional[Union[np.ndarray, list, torch.Tensor]], optional) – indices to specify which cloth prims to query. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

  • clone (bool, optional) – True to return a clone of the internal buffer. Otherwise False. Defaults to True.

Returns

mass tensor with shape (M, max_particles_per_cloth)

Return type

Union[Tuple[np.ndarray, np.ndarray], Tuple[torch.Tensor, torch.Tensor]]

get_pressures(indices: Optional[Union[numpy.ndarray, list, torch.Tensor]] = None, clone: bool = True) Union[numpy.ndarray, torch.Tensor]

Gets the pressures of the cloths indicated by the indices.

Parameters
  • indices (Optional[Union[np.ndarray, list, torch.Tensor]], optional) – indices to specify which cloth prims to query. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

  • clone (bool, optional) – True to return a clone of the internal buffer. Otherwise False. Defaults to True.

Returns

cloths pressure with shape (M, ).

Return type

Union[Tuple[np.ndarray, np.ndarray], Tuple[torch.Tensor, torch.Tensor]]

get_self_collision_filters(indices: Optional[Union[numpy.ndarray, list, torch.Tensor]] = None, clone: bool = True) Union[numpy.ndarray, torch.Tensor]

Gets the self collision filters for the cloths indicated by the indices.

Parameters
  • indices (Optional[Union[np.ndarray, list, torch.Tensor]], optional) – indices to specify which cloth prims to query. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

  • clone (bool, optional) – True to return a clone of the internal buffer. Otherwise False. Defaults to True.

Returns

the self collision filters tensor with shape (M, )

Return type

Union[Tuple[np.ndarray, np.ndarray], Tuple[torch.Tensor, torch.Tensor]]

get_self_collisions(indices: Optional[Union[numpy.ndarray, list, torch.Tensor]] = None, clone: bool = True) Union[numpy.ndarray, torch.Tensor]

Gets the self collision for the cloths indicated by the indices.

Parameters
  • indices (Optional[Union[np.ndarray, list, torch.Tensor]], optional) – indices to specify which cloth prims to query. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

  • clone (bool, optional) – True to return a clone of the internal buffer. Otherwise False. Defaults to True.

Returns

the self collision tensor with shape (M, )

Return type

Union[Tuple[np.ndarray, np.ndarray], Tuple[torch.Tensor, torch.Tensor]]

get_spring_dampings(indices: Optional[Union[numpy.ndarray, list, torch.Tensor]] = None, clone: bool = True) Union[numpy.ndarray, torch.Tensor]

Gets the spring damping for the cloths indicated by the indices.

Parameters
  • indices (Optional[Union[np.ndarray, list, torch.Tensor]], optional) – indices to specify which cloth prims to query. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

  • clone (bool, optional) – True to return a clone of the internal buffer. Otherwise False. Defaults to True.

Returns

damping tensor with shape (M, max_springs_per_cloth)

Return type

Union[Tuple[np.ndarray, np.ndarray], Tuple[torch.Tensor, torch.Tensor]]

get_stretch_stiffnesses(indices: Optional[Union[numpy.ndarray, list, torch.Tensor]] = None, clone: bool = True) Union[numpy.ndarray, torch.Tensor]

Gets the spring stretch stiffness for the cloths indicated by the indices.

Parameters
  • indices (Optional[Union[np.ndarray, list, torch.Tensor]], optional) – indices to specify which cloth prims to query. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

  • clone (bool, optional) – True to return a clone of the internal buffer. Otherwise False. Defaults to True.

Returns

stiffness tensor with shape (M, max_springs_per_cloth)

Return type

Union[Tuple[np.ndarray, np.ndarray], Tuple[torch.Tensor, torch.Tensor]]

get_velocities(indices: Optional[Union[numpy.ndarray, list, torch.Tensor]] = None, clone: bool = True) Union[numpy.ndarray, torch.Tensor]

Gets the particle velocities for the cloths indicated by the indices.

Parameters
  • indices (Optional[Union[np.ndarray, list, torch.Tensor]], optional) – indices to specify which cloth prims to query. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

  • clone (bool, optional) – True to return a clone of the internal buffer. Otherwise False. Defaults to True.

Returns

velocity tensor with shape (M, max_particles_per_cloth, 3)

Return type

Union[Tuple[np.ndarray, np.ndarray], Tuple[torch.Tensor, torch.Tensor]]

get_visibilities(indices: Optional[Union[numpy.ndarray, list, torch.Tensor, warp.types.array]] = None) Union[numpy.ndarray, torch.Tensor, warp.types.indexedarray]

Returns the current visibilities of the prims in stage.

Parameters

indices (Optional[Union[np.ndarray, list, torch.Tensor, wp.array]], optional) – indices to specify which prims to query. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

Returns

Shape (M,) with type bool, where each item holds True

if the prim is visible in stage. False otherwise.

Return type

Union[np.ndarray, torch.Tensor, wp.indexedarray]

Example:

>>> # get all visibilities. Returned shape is (5,) for the example: 5 envs
>>> prims.get_visibilities()
[ True  True  True  True  True]
>>>
>>> # get the visibilities for the first, middle and last of the 5 envs. Returned shape is (3,)
>>> prims.get_visibilities(indices=np.array([0, 2, 4]))
[ True  True  True]
get_world_poses(indices: Optional[Union[numpy.ndarray, list, torch.Tensor, warp.types.array]] = None) Union[Tuple[numpy.ndarray, numpy.ndarray], Tuple[torch.Tensor, torch.Tensor], Tuple[warp.types.indexedarray, warp.types.indexedarray]]

Get the poses of the prims in the view with respect to the world’s frame

Parameters

indices (Optional[Union[np.ndarray, list, torch.Tensor, wp.array]], optional) – indices to specify which prims to query. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

Returns

first index is positions in the world frame of the prims. shape is (M, 3).

second index is quaternion orientations in the world frame of the prims. quaternion is scalar-first (w, x, y, z). shape is (M, 4).

Return type

Union[Tuple[np.ndarray, np.ndarray], Tuple[torch.Tensor, torch.Tensor], Tuple[wp.indexedarray, wp.indexedarray]]

Example:

>>> # get all prims poses with respect to the world's frame.
>>> # Returned shape is position (5, 3) and orientation (5, 4) for the example: 5 envs
>>> positions, orientations = prims.get_world_poses()
>>> positions
[[ 1.5  -0.75  0.  ]
 [ 1.5   0.75  0.  ]
 [ 0.   -0.75  0.  ]
 [ 0.    0.75  0.  ]
 [-1.5  -0.75  0.  ]]
>>> orientations
[[1. 0. 0. 0.]
 [1. 0. 0. 0.]
 [1. 0. 0. 0.]
 [1. 0. 0. 0.]
 [1. 0. 0. 0.]]
>>>
>>> # get only the prims poses with respect to the world's frame for the first, middle and last of the 5 envs.
>>> # Returned shape is position (3, 3) and orientation (3, 4) for the example: 3 envs selected
>>> positions, orientations = prims.get_world_poses(indices=np.array([0, 2, 4]))
>>> positions
[[ 1.5  -0.75  0.  ]
 [ 0.   -0.75  0.  ]
 [-1.5  -0.75  0.  ]]
>>> orientations
[[1. 0. 0. 0.]
 [1. 0. 0. 0.]
 [1. 0. 0. 0.]]
get_world_positions(indices: Optional[Union[numpy.ndarray, list, torch.Tensor]] = None, clone: bool = True) Union[numpy.ndarray, torch.Tensor]

Gets the particle world positions for the cloths indicated by the indices.

Parameters
  • indices (Optional[Union[np.ndarray, list, torch.Tensor]], optional) – indices to specify which cloth prims to query. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

  • clone (bool, optional) – True to return a clone of the internal buffer. Otherwise False. Defaults to True.

Returns

position tensor with shape (M, max_particles_per_cloth, 3)

Return type

Union[Tuple[np.ndarray, np.ndarray], Tuple[torch.Tensor, torch.Tensor]]

get_world_scales(indices: Optional[Union[numpy.ndarray, list, torch.Tensor, warp.types.array]] = None) Union[numpy.ndarray, torch.Tensor, warp.types.indexedarray]

Get prim scales in the view with respect to the world’s frame

Parameters

indices (Optional[Union[np.ndarray, list, torch.Tensor, wp.array]], optional) – indices to specify which prims to query. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

Returns

scales applied to the prim’s dimensions in the world frame. shape is (M, 3).

Return type

Union[np.ndarray, torch.Tensor, wp.indexedarray]

Example:

>>> # get all prims scales with respect to the world's frame.
>>> # Returned shape is (5, 3) for the example: 5 envs
>>> prims.get_world_scales()
[[1. 1. 1.]
 [1. 1. 1.]
 [1. 1. 1.]
 [1. 1. 1.]
 [1. 1. 1.]]
>>>
>>> # get only the prims scales with respect to the world's frame for the first, middle and last of the 5 envs.
>>> # Returned shape is (3, 3) for the example: 3 envs selected
>>> prims.get_world_scales(indices=np.array([0, 2, 4]))
[[1. 1. 1.]
 [1. 1. 1.]
 [1. 1. 1.]]
initialize(physics_sim_view: Optional[omni.physics.tensors.bindings._physicsTensors.SimulationView] = None) None

Create a physics simulation view if not passed and creates a rigid body view in physX.

Parameters

physics_sim_view (omni.physics.tensors.SimulationView, optional) – current physics simulation view. Defaults to None.

Returns: bool: True if the prim corresponds to a non root link in an articulation. Otherwise False.

is_physics_handle_valid() bool
Returns

True if the physics handle of the view is valid (i.e physics is initialized for the view). Otherwise False.

Return type

bool

is_valid(indices: Optional[Union[numpy.ndarray, list, torch.Tensor, warp.types.array]] = None) bool

Check that all prims have a valid USD Prim

Parameters

indices (Optional[Union[np.ndarray, list, torch.Tensor, wp.array]], optional) – indices to specify which prims to query. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

Returns

True if all prim paths specified in the view correspond to a valid prim in stage. False otherwise.

Return type

bool

Example:

>>> prims.is_valid()
True
is_visual_material_applied(indices: Optional[Union[numpy.ndarray, list, torch.Tensor, warp.types.array]] = None) List[bool]

Check if there is a visual material applied

Parameters

indices (Optional[Union[np.ndarray, list, torch.Tensor, wp.array]], optional) – indices to specify which prims to query. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

Returns

True if there is a visual material applied is applied to the corresponding prim in the view. False otherwise.

Return type

List[bool]

Example:

>>> # given a visual material that is applied only to the first and the last environment
>>> prims.is_visual_material_applied()
[True, False, False, False, True]
>>>
>>> # check for the first, middle and last of the 5 envs
>>> prims.is_visual_material_applied(indices=np.array([0, 2, 4]))
[True, False, True]
property max_particles_per_cloth: int

Returns: int: maximum number of particles per cloth.

property max_springs_per_cloth: int

Returns: int: maximum number of springs per cloth.

property name: str

Returns: str: name given to the prims view when instantiating it.

post_reset() None

Reset the prims to its default state (positions and orientations)

Example:

>>> prims.post_reset()
property prim_paths: List[str]
Returns

list of prim paths in the stage encapsulated in this view.

Return type

List[str]

Example:

>>> prims.prim_paths
['/World/envs/env_0', '/World/envs/env_1', '/World/envs/env_2', '/World/envs/env_3', '/World/envs/env_4']
property prims: List[pxr.Usd.Prim]
Returns

List of USD Prim objects encapsulated in this view.

Return type

List[Usd.Prim]

Example:

>>> prims.prims
[Usd.Prim(</World/envs/env_0>), Usd.Prim(</World/envs/env_1>), Usd.Prim(</World/envs/env_2>),
 Usd.Prim(</World/envs/env_3>), Usd.Prim(</World/envs/env_4>)]
set_cloths_bend_stiffnesses(values: Optional[Union[numpy.ndarray, torch.Tensor]], indices: Optional[Union[numpy.ndarray, list, torch.Tensor]] = None) None

Sets a single value of bend stiffnesses to all the springs within cloths indicated by the indices.

Parameters
  • values (Union[np.ndarray, torch.Tensor]) – cloth spring bend stiffness values with the shape (M, ).

  • indices (Optional[Union[np.ndarray, list, torch.Tensor]], optional) – indices to specify which cloth prims to manipulate. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

set_cloths_dampings(values: Optional[Union[numpy.ndarray, torch.Tensor]], indices: Optional[Union[numpy.ndarray, list, torch.Tensor]] = None) None

Sets a single value of damping to all the springs within cloths indicated by the indices.

Parameters
  • values (Union[np.ndarray, torch.Tensor]) – cloth spring damping with the shape (M, ).

  • indices (Optional[Union[np.ndarray, list, torch.Tensor]], optional) – indices to specify which cloth prims to manipulate. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

set_cloths_shear_stiffnesses(values: Optional[Union[numpy.ndarray, torch.Tensor]], indices: Optional[Union[numpy.ndarray, list, torch.Tensor]] = None) None

Sets a single value of shear stiffnesses to all the springs within cloths indicated by the indices.

Parameters
  • values (Union[np.ndarray, torch.Tensor]) – cloth spring shear stiffness values with the shape (M, ).

  • indices (Optional[Union[np.ndarray, list, torch.Tensor]], optional) – indices to specify which cloth prims to manipulate. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

set_cloths_stretch_stiffnesses(values: Optional[Union[numpy.ndarray, torch.Tensor]], indices: Optional[Union[numpy.ndarray, list, torch.Tensor]] = None) None

Sets a single value of stretch stiffnesses to all the springs within cloths indicated by the indices.

Parameters
  • values (Union[np.ndarray, torch.Tensor]) – cloth spring stretch stiffness values with the shape (M, ).

  • indices (Optional[Union[np.ndarray, list, torch.Tensor]], optional) – indices to specify which cloth prims to manipulate. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

set_default_state(positions: Optional[Union[numpy.ndarray, torch.Tensor, warp.types.array]] = None, orientations: Optional[Union[numpy.ndarray, torch.Tensor, warp.types.array]] = None, indices: Optional[Union[numpy.ndarray, list, torch.Tensor, warp.types.array]] = None) None

Set the default state of the prims (positions and orientations), that will be used after each reset.

Note

The default states will be set during post-reset (e.g., calling .post_reset() or world.reset() methods)

Parameters
  • positions (Optional[Union[np.ndarray, torch.Tensor, wp.array]], optional) – positions in the world frame of the prim. shape is (M, 3). Defaults to None, which means left unchanged.

  • orientations (Optional[Union[np.ndarray, torch.Tensor, wp.array]], optional) – quaternion orientations in the world frame of the prim. quaternion is scalar-first (w, x, y, z). shape is (M, 4). Defaults to None, which means left unchanged.

  • indices (Optional[Union[np.ndarray, list, torch.Tensor, wp.array]], optional) – indices to specify which prims to manipulate. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

Example:

>>> # configure default states for all prims
>>> positions = np.zeros((num_envs, 3))
>>> positions[:, 0] = np.arange(num_envs)
>>> orientations = np.tile(np.array([1.0, 0.0, 0.0, 0.0]), (num_envs, 1))
>>> prims.set_default_state(positions=positions, orientations=orientations)
>>>
>>> # set default states during post-reset
>>> prims.post_reset()
set_local_poses(translations: Optional[Union[numpy.ndarray, torch.Tensor, warp.types.array]] = None, orientations: Optional[Union[numpy.ndarray, torch.Tensor, warp.types.array]] = None, indices: Optional[Union[numpy.ndarray, list, torch.Tensor, warp.types.array]] = None) None

Set prim poses in the view with respect to the local frame (the prim’s parent frame)

Warning

This method will change (teleport) the prim poses immediately to the indicated value

Parameters
  • translations (Optional[Union[np.ndarray, torch.Tensor, wp.array]], optional) – translations in the local frame of the prims (with respect to its parent prim). shape is (M, 3). Defaults to None, which means left unchanged.

  • orientations (Optional[Union[np.ndarray, torch.Tensor, wp.array]], optional) – quaternion orientations in the local frame of the prims. quaternion is scalar-first (w, x, y, z). shape is (M, 4). Defaults to None, which means left unchanged.

  • indices (Optional[Union[np.ndarray, list, torch.Tensor, wp.array]], optional) – indices to specify which prims to manipulate. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

Hint

This method belongs to the methods used to set the prim state

Example:

>>> # reposition all prims
>>> positions = np.zeros((num_envs, 3))
>>> positions[:,0] = np.arange(num_envs)
>>> orientations = np.tile(np.array([1.0, 0.0, 0.0, 0.0]), (num_envs, 1))
>>> prims.set_local_poses(positions, orientations)
>>>
>>> # reposition only the prims for the first, middle and last of the 5 envs
>>> positions = np.zeros((3, 3))
>>> positions[:,1] = np.arange(3)
>>> orientations = np.tile(np.array([1.0, 0.0, 0.0, 0.0]), (3, 1))
>>> prims.set_local_poses(positions, orientations, indices=np.array([0, 2, 4]))
set_local_scales(scales: Optional[Union[numpy.ndarray, torch.Tensor, warp.types.array]], indices: Optional[Union[numpy.ndarray, list, torch.Tensor, warp.types.array]] = None) None

Set prim scales in the view with respect to the local frame (the prim’s parent frame)

Parameters
  • scales (Optional[Union[np.ndarray, torch.Tensor, wp.array]]) – scales to be applied to the prim’s dimensions in the view. shape is (M, 3).

  • indices (Optional[Union[np.ndarray, list, torch.Tensor, wp.array]], optional) – indices to specify which prims to manipulate. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

Example:

>>> # set the scale for all prims. Since there are 5 envs, the scale is repeated 5 times
>>> scales = np.tile(np.array([1.0, 0.75, 0.5]), (num_envs, 1))
>>> prims.set_local_scales(scales)
>>>
>>> # set the scale for the first, middle and last of the 5 envs
>>> scales = np.tile(np.array([1.0, 0.75, 0.5]), (3, 1))
>>> prims.set_local_scales(scales, indices=np.array([0, 2, 4]))
set_particle_groups(particle_groups: Optional[Union[numpy.ndarray, torch.Tensor]], indices: Optional[Union[numpy.ndarray, list, torch.Tensor]] = None) None

Sets the particle group of the cloths indicated by the indices.

Parameters
  • particle_groups (Union[np.ndarray, torch.Tensor]) – particle group with shape (M, ).

  • indices (Optional[Union[np.ndarray, list, torch.Tensor]], optional) – indices to specify which cloth prims to manipulate. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

set_particle_masses(masses: Optional[Union[numpy.ndarray, torch.Tensor]], indices: Optional[Union[numpy.ndarray, list, torch.Tensor]] = None) None

Sets the particle masses for the cloths indicated by the indices.

Parameters
  • masses (Union[np.ndarray, torch.Tensor]) – cloth particle masses with the shape (M, max_particles_per_cloth, 3).

  • indices (Optional[Union[np.ndarray, list, torch.Tensor]], optional) – indices to specify which cloth prims to manipulate. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

set_pressures(pressures: Optional[Union[numpy.ndarray, torch.Tensor]], indices: Optional[Union[numpy.ndarray, list, torch.Tensor]] = None) None

Sets the pressures of the cloths indicated by the indices.

Parameters
  • pressures (Union[np.ndarray, torch.Tensor]) – cloths pressure with shape (M, ).

  • indices (Optional[Union[np.ndarray, list, torch.Tensor]], optional) – indices to specify which cloth prims to manipulate. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

set_self_collision_filters(self_collision_filters: Optional[Union[numpy.ndarray, torch.Tensor]], indices: Optional[Union[numpy.ndarray, list, torch.Tensor]] = None) None

Sets the self collision filters for the cloths indicated by the indices.

Parameters
  • self_collision_filters (Union[np.ndarray, torch.Tensor]) – self collision filters with the shape (M, ).

  • indices (Optional[Union[np.ndarray, list, torch.Tensor]], optional) – indices to specify which cloth prims to manipulate. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

set_self_collisions(self_collisions: Optional[Union[numpy.ndarray, torch.Tensor]], indices: Optional[Union[numpy.ndarray, list, torch.Tensor]] = None) None

Sets the self collision flags for the cloths indicated by the indices.

Parameters
  • self_collisions (Union[np.ndarray, torch.Tensor]) – self collision flag with the shape (M, ).

  • indices (Optional[Union[np.ndarray, list, torch.Tensor]], optional) – indices to specify which cloth prims to manipulate. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

set_spring_dampings(damping: Optional[Union[numpy.ndarray, torch.Tensor]], indices: Optional[Union[numpy.ndarray, list, torch.Tensor]] = None) None

Sets the spring damping for the cloths indicated by the indices.

Parameters
  • damping (Union[np.ndarray, torch.Tensor]) – cloth spring damping with the shape (M, max_springs_per_cloth).

  • indices (Optional[Union[np.ndarray, list, torch.Tensor]], optional) – indices to specify which cloth prims to manipulate. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

set_stretch_stiffnesses(stiffness: Optional[Union[numpy.ndarray, torch.Tensor]], indices: Optional[Union[numpy.ndarray, list, torch.Tensor]] = None) None

Sets the spring stretch stiffness values for springs within the cloths indicated by the indices.

Parameters
  • stiffness (Union[np.ndarray, torch.Tensor]) – cloth spring stiffness with the shape (M, max_springs_per_cloth).

  • indices (Optional[Union[np.ndarray, list, torch.Tensor]], optional) – indices to specify which cloth prims to manipulate. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

set_velocities(velocities: Optional[Union[numpy.ndarray, torch.Tensor]], indices: Optional[Union[numpy.ndarray, list, torch.Tensor]] = None) None

Sets the particle velocities for the cloths indicated by the indices.

Parameters
  • velocities (Union[np.ndarray, torch.Tensor]) – particle velocities with the shape (M, max_particles_per_cloth, 3).

  • indices (Optional[Union[np.ndarray, list, torch.Tensor]], optional) – indices to specify which cloth prims to manipulate. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

set_visibilities(visibilities: Union[numpy.ndarray, torch.Tensor, warp.types.array], indices: Optional[Union[numpy.ndarray, list, torch.Tensor, warp.types.array]] = None) None

Set the visibilities of the prims in stage

Parameters
  • visibilities (Union[np.ndarray, torch.Tensor, wp.array]) – flag to set the visibilities of the usd prims in stage. Shape (M,). Where M <= size of the encapsulated prims in the view.

  • indices (Optional[Union[np.ndarray, list, torch.Tensor, wp.array]], optional) – indices to specify which prims to manipulate. Shape (M,). Defaults to None (i.e: all prims in the view).

Example:

>>> # make all prims not visible in the stage
>>> prims.set_visibilities(visibilities=[False] * num_envs)
set_world_poses(positions: Optional[Union[numpy.ndarray, torch.Tensor, warp.types.array]] = None, orientations: Optional[Union[numpy.ndarray, torch.Tensor, warp.types.array]] = None, indices: Optional[Union[numpy.ndarray, list, torch.Tensor, warp.types.array]] = None) None

Set prim poses in the view with respect to the world’s frame

Warning

This method will change (teleport) the prim poses immediately to the indicated value

Parameters
  • positions (Optional[Union[np.ndarray, torch.Tensor, wp.array]], optional) – positions in the world frame of the prims. shape is (M, 3). Defaults to None, which means left unchanged.

  • orientations (Optional[Union[np.ndarray, torch.Tensor, wp.array]], optional) – quaternion orientations in the world frame of the prims. quaternion is scalar-first (w, x, y, z). shape is (M, 4). Defaults to None, which means left unchanged.

  • indices (Optional[Union[np.ndarray, list, torch.Tensor, wp.array]], optional) – indices to specify which prims to query. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

Hint

This method belongs to the methods used to set the prim state

Example:

>>> # reposition all prims in row (x-axis)
>>> positions = np.zeros((num_envs, 3))
>>> positions[:,0] = np.arange(num_envs)
>>> orientations = np.tile(np.array([1.0, 0.0, 0.0, 0.0]), (num_envs, 1))
>>> prims.set_world_poses(positions, orientations)
>>>
>>> # reposition only the prims for the first, middle and last of the 5 envs in column (y-axis)
>>> positions = np.zeros((3, 3))
>>> positions[:,1] = np.arange(3)
>>> orientations = np.tile(np.array([1.0, 0.0, 0.0, 0.0]), (3, 1))
>>> prims.set_world_poses(positions, orientations, indices=np.array([0, 2, 4]))
set_world_positions(positions: Optional[Union[numpy.ndarray, torch.Tensor]], indices: Optional[Union[numpy.ndarray, list, torch.Tensor]] = None) None

Sets the particle world positions for the cloths indicated by the indices.

Parameters
  • positions (Union[np.ndarray, torch.Tensor]) – particle positions with the shape (M, max_particles_per_cloth, 3).

  • indices (Optional[Union[np.ndarray, list, torch.Tensor]], optional) – indices to specify which cloth prims to manipulate. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

Particle System

class ParticleSystem(prim_path: str, name: Optional[str] = 'particle_system', particle_system_enabled: Optional[bool] = None, simulation_owner: Optional[str] = None, contact_offset: Optional[float] = None, rest_offset: Optional[float] = None, particle_contact_offset: Optional[float] = None, solid_rest_offset: Optional[float] = None, fluid_rest_offset: Optional[float] = None, enable_ccd: Optional[bool] = None, solver_position_iteration_count: Optional[float] = None, max_depenetration_velocity: Optional[float] = None, wind: Optional[Sequence[float]] = None, max_neighborhood: Optional[int] = None, max_velocity: Optional[float] = None, global_self_collision_enabled: Optional[bool] = None, non_particle_collision_enabled: Optional[bool] = None)

A wrapper around PhysX particle system.

PhysX uses GPU-accelerated position-based-dynamics (PBD) particle simulation [1]. The particle system can be used to simulate fluids, cloth and inflatables [2].

The wrapper is useful for creating and setting solver parameters common to the particle objects associated with the system. The particle system’s solver parameters cannot be changed once the scene is playing.

Note

CPU simulation of particles is not supported. PhysX must be simulated with GPU enabled.

Reference:

[1] https://mmacklin.com/pbf_sig_preprint.pdf [2] https://docs.omniverse.nvidia.com/prod_extensions/prod_extensions/ext_physics.html#particle-simulation

apply_particle_anisotropy() pxr.PhysxSchema.PhysxParticleAnisotropyAPI

Applies anisotropy to the particle system.

This is used to compute anisotropic scaling of particles in a post-processing step. It only affects the rendering output including iso-surface generation.

apply_particle_isotropy() pxr.PhysxSchema.PhysxParticleAnisotropyAPI

Applies iso-surface extraction to the particle system.

This is used to define settings to extract an iso-surface from the particles in a post-processing step. It only affects the rendering output including iso-surface generation.

apply_particle_material(particle_materials: omni.isaac.core.materials.particle_material.ParticleMaterial) None
apply_particle_smoothing() pxr.PhysxSchema.PhysxParticleSmoothingAPI

Applies smoothing to the simulated particle system.

This is used to control smoothing of particles in a post-processing step. It only affects the rendering output including iso-surface generation.

get_applied_particle_material() omni.isaac.core.materials.particle_material.ParticleMaterial
get_contact_offset() float
Returns

The contact offset used for collisions with non-particle objects.

Return type

float

get_enable_ccd() bool
Returns

Whether continuous collision detection for particles is enabled or disabled.

Return type

bool

get_fluid_rest_offset() float
Returns

The rest offset used for fluid-fluid particle interactions.

Return type

float

get_global_self_collision_enabled() bool
Returns

Whether self collisions to follow particle-object-specific settings

is enabled or disabled.

Return type

bool

get_max_depenetration_velocity() None
Returns

The maximum velocity permitted between intersecting particles.

Return type

float

get_max_neighborhood() int
Returns

The particle neighborhood size.

Return type

int

get_max_velocity() float
Returns

The maximum particle velocity.

Return type

float

get_particle_contact_offset() float
Returns

The contact offset used for interactions between particles.

Return type

float

get_particle_system_enabled() bool
Returns

Whether particle system is enabled or not.

Return type

bool

get_rest_offset() float
Returns

The rest offset used for collisions with non-particle objects.

Return type

float

get_simulation_owner() pxr.Usd.Prim
Returns

The physics scene prim attached to particle system.

Return type

Usd.Prim

get_solid_rest_offset() float
Returns

The rest offset used for solid-solid or solid-fluid particle interactions.

Return type

float

get_solver_position_iteration_count() int
Returns

The number of solver iterations for positions.

Return type

int

get_wind() Sequence[float]
Returns

The wind applied to the current particle system.

Return type

Sequence[float]

initialize(physics_sim_view=None) None
is_valid() bool
Returns

True is the current prim path corresponds to a valid prim in stage. False otherwise.

Return type

bool

property name: Optional[str]

Returns: str: name given to the prim when instantiating it. Otherwise None.

property particle_system: pxr.PhysxSchema.PhysxParticleSystem

Returns: PhysxSchema.PhysxParticleSystem: The particle system.

post_reset() None
property prim: pxr.Usd.Prim

Returns: Usd.Prim: The USD prim present.

property prim_path: str

Returns: str: The stage path to the particle system.

set_contact_offset(value: float) None

Set the contact offset used for collisions with non-particle objects such as rigid or deformable bodies.

Parameters

value (float) – The contact offset.

set_enable_ccd(value: bool) None

Enable continuous collision detection for particles.

Parameters

value (bool) – Whether to enable or disable.

set_fluid_rest_offset(value: float) None

Set the rest offset used for fluid-fluid particle interactions.

Note: Must be smaller than particle contact offset.

Parameters

value (float) – The rest offset.

set_global_self_collision_enabled(value: bool) None

Enable self collisions to follow particle-object-specific settings.

If True, self collisions follow particle-object-specific settings. If False, all particle self collisions are disabled, regardless of any other settings.

Note: Improves performance if self collisions are not needed.

Parameters

value (bool) – Whether to enable or disable.

set_max_depenetration_velocity(value: float) None

Set the maximum velocity permitted to be introduced by the solver to depenetrate intersecting particles.

Parameters

value (float) – The maximum depenetration velocity.

set_max_neighborhood(value: int) None

Set the particle neighborhood size.

Parameters

value (int) – The neighborhood size.

set_max_velocity(value: float) None

Set the maximum particle velocity.

Parameters

value (float) – The maximum velocity.

set_particle_contact_offset(value: float) None

Set the contact offset used for interactions between particles.

Note: Must be larger than solid and fluid rest offsets.

Parameters

value (float) – The contact offset.

set_particle_system_enabled(value: bool) None

Set enabling of the particle system.

Parameters

value (bool) – Whether to enable or disable.

set_rest_offset(value: float) None

Set the rest offset used for collisions with non-particle objects such as rigid or deformable bodies.

Parameters

value (float) – The rest offset.

set_simulation_owner(value: str) None

Set the PhysicsScene that simulates this particle system.

Parameters

value (str) – The prim path to the physics scene.

set_solid_rest_offset(value: float) None

Set the rest offset used for solid-solid or solid-fluid particle interactions.

Note: Must be smaller than particle contact offset.

Parameters

value (float) – The rest offset.

set_solver_position_iteration_count(value: int) None

Set the number of solver iterations for position.

Parameters

value (int) – Number of solver iterations.

set_wind(value: Sequence[float]) None

Set the wind velocity applied to the current particle system.

Parameters

value (Sequence[float]) – The wind applied to the current particle system.

Particle System View

class ParticleSystemView(prim_paths_expr: str, name: str = 'particle_system_view', particle_systems_enabled: Optional[Union[numpy.ndarray, torch.Tensor]] = None, simulation_owners: Optional[Sequence[str]] = None, contact_offsets: Optional[Union[numpy.ndarray, torch.Tensor]] = None, rest_offsets: Optional[Union[numpy.ndarray, torch.Tensor]] = None, particle_contact_offsets: Optional[Union[numpy.ndarray, torch.Tensor]] = None, solid_rest_offsets: Optional[Union[numpy.ndarray, torch.Tensor]] = None, fluid_rest_offsets: Optional[Union[numpy.ndarray, torch.Tensor]] = None, enable_ccds: Optional[Union[numpy.ndarray, torch.Tensor]] = None, solver_position_iteration_counts: Optional[Union[numpy.ndarray, torch.Tensor]] = None, max_depenetration_velocities: Optional[Union[numpy.ndarray, torch.Tensor]] = None, winds: Optional[Union[numpy.ndarray, torch.Tensor]] = None, max_neighborhoods: Optional[int] = None, max_velocities: Optional[Union[numpy.ndarray, torch.Tensor]] = None, global_self_collisions_enabled: Optional[Union[numpy.ndarray, torch.Tensor]] = None)

Provides high level functions to deal with particle systems (1 or more particle systems) as well as its attributes/ properties. This object wraps all matching particle systems found at the regex provided at the prim_paths_expr. Note: not all the attributes of the PhysxSchema.PhysxParticleSystem is currently controlled with this view class Tensor API support will be added in the future to extend the functionality of this class to applications beyond cloth.

apply_particle_materials(particle_materials: Union[omni.isaac.core.materials.particle_material.ParticleMaterial, List[omni.isaac.core.materials.particle_material.ParticleMaterial]], indices: Optional[Union[numpy.ndarray, list, torch.Tensor]] = None) None

Used to apply particle material to prims in the view.

Parameters
  • particle_materials (Union[ParticleMaterial, List[ParticleMaterial]]) – particle materials to be applied to prims in the view. Note: if a physics material is not defined, the defaults will be used from PhysX. If a list is provided then its size has to be equal the view’s size or indices size. If one material is provided it will be applied to all prims in the view.

  • indices (Optional[Union[np.ndarray, list, torch.Tensor]], optional) – indices to specify which prims to manipulate. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

Raises

Exception – length of physics materials != length of prims indexed

property count: int

Returns: int: number of rigid shapes for the prims in the view.

get_applied_particle_materials(indices: Optional[Union[numpy.ndarray, list, torch.Tensor]] = None) List[omni.isaac.core.materials.particle_material.ParticleMaterial]

Gets the applied particle material to prims in the view.

Parameters

indices (Optional[Union[np.ndarray, list, torch.Tensor]], optional) – indices to specify which prims to query. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

Returns

the current applied particle materials for prims in the view.

Return type

List[ParticleMaterial]

get_contact_offsets(indices: Optional[Union[numpy.ndarray, list, torch.Tensor]] = None) Union[numpy.ndarray, torch.Tensor]
Returns

The contact offset used for collisions with non-particle objects for each particle system. shape is (M, ).

Return type

Union[np.ndarray, torch.Tensor]

Parameters

indices (Optional[Union[np.ndarray, list, torch.Tensor]], optional) – indices to specify which prims to query. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view)

get_enable_ccds(indices: Optional[Union[numpy.ndarray, list, torch.Tensor]] = None) Union[numpy.ndarray, torch.Tensor]
Returns

Whether continuous collision detection for particles is enabled or disabled for each particle system. shape is (M, ).

Return type

Union[np.ndarray, torch.Tensor]

Parameters

indices (Optional[Union[np.ndarray, list, torch.Tensor]], optional) – indices to specify which prims to query. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view)

get_fluid_rest_offsets(indices: Optional[Union[numpy.ndarray, list, torch.Tensor]] = None, clone: bool = True) Union[numpy.ndarray, torch.Tensor]
Returns

The rest offset used for fluid-fluid particle interactions. shape is (M, ).

Return type

Union[np.ndarray, torch.Tensor]

Parameters
  • indices (Optional[Union[np.ndarray, list, torch.Tensor]], optional) – indices to specify which prims to query. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view)

  • clone (bool, optional) – True to return a clone of the internal buffer. Otherwise False. Defaults to True.

get_global_self_collisions_enabled(indices: Optional[Union[numpy.ndarray, list, torch.Tensor]] = None) Union[numpy.ndarray, torch.Tensor]
Returns

Whether self collisions to follow particle-object-specific settings

is enabled or disabled. for each particle system. shape is (M, ).

Return type

Union[np.ndarray, torch.Tensor]

Parameters

indices (Optional[Union[np.ndarray, list, torch.Tensor]], optional) – indices to specify which prims to query. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view)

get_max_depenetration_velocities(indices: Optional[Union[numpy.ndarray, list, torch.Tensor]] = None) Union[numpy.ndarray, torch.Tensor]
Returns

The maximum velocity permitted to be introduced by the solver to

depenetrate intersecting particles for particle systems for each particle system. shape is (M, ).

Return type

Union[np.ndarray, torch.Tensor]

Parameters

indices (Optional[Union[np.ndarray, list, torch.Tensor]], optional) – indices to specify which prims to query. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view)

get_max_neighborhoods(indices: Optional[Union[numpy.ndarray, list, torch.Tensor]] = None) Union[numpy.ndarray, torch.Tensor]
Returns

The particle neighborhood size for each particle system. shape is (M, ).

Return type

Union[np.ndarray, torch.Tensor]

Parameters

indices (Optional[Union[np.ndarray, list, torch.Tensor]], optional) – indices to specify which prims to query. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view)

get_max_velocities(indices: Optional[Union[numpy.ndarray, list, torch.Tensor]] = None) Union[numpy.ndarray, torch.Tensor]
Returns

The maximum particle velocities for each particle system. shape is (M, ).

Return type

Union[np.ndarray, torch.Tensor]

Parameters

indices (Optional[Union[np.ndarray, list, torch.Tensor]], optional) – indices to specify which prims to query. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view)

get_particle_contact_offsets(indices: Optional[Union[numpy.ndarray, list, torch.Tensor]] = None, clone: bool = True) Union[numpy.ndarray, torch.Tensor]
Returns

The contact offset used for interactions between particles in the view concatenated. shape is (M, ).

Return type

Union[np.ndarray, torch.Tensor]

Parameters
  • indices (Optional[Union[np.ndarray, list, torch.Tensor]], optional) – indices to specify which prims to query. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view)

  • clone (bool, optional) – True to return a clone of the internal buffer. Otherwise False. Defaults to True.

get_particle_systems_enabled(indices: Optional[Union[numpy.ndarray, list, torch.Tensor]] = None) Union[numpy.ndarray, torch.Tensor]
Returns

Whether particle system is enabled or not for each particle system. shape is (M, ).

Return type

Union[np.ndarray, torch.Tensor]

Parameters

indices (Optional[Union[np.ndarray, list, torch.Tensor]], optional) – indices to specify which prims to query. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view)

get_rest_offsets(indices: Optional[Union[numpy.ndarray, list, torch.Tensor]] = None) Union[numpy.ndarray, torch.Tensor]
Returns

The rest offset used for collisions with non-particle objects for each particle system. shape is (M, ).

Return type

Union[np.ndarray, torch.Tensor]

Parameters

indices (Optional[Union[np.ndarray, list, torch.Tensor]], optional) – indices to specify which prims to query. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view)

get_simulation_owners(indices: Optional[Union[numpy.ndarray, list, torch.Tensor]] = None) Sequence[str]
Returns

The physics scene prim path attached to particle system. shape is (M, ).

Return type

Sequence[str]

Parameters

indices (Optional[Union[np.ndarray, list, torch.Tensor]], optional) – indices to specify which prims to query. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view)

get_solid_rest_offsets(indices: Optional[Union[numpy.ndarray, list, torch.Tensor]] = None, clone: bool = True) Union[numpy.ndarray, torch.Tensor]
Returns

The rest offset used for solid-solid or solid-fluid particle interactions. shape is (M, ).

Return type

Union[np.ndarray, torch.Tensor]

Parameters
  • indices (Optional[Union[np.ndarray, list, torch.Tensor]], optional) – indices to specify which prims to query. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view)

  • clone (bool, optional) – True to return a clone of the internal buffer. Otherwise False. Defaults to True.

get_solver_position_iteration_counts(indices: Optional[Union[numpy.ndarray, list, torch.Tensor]] = None) Union[numpy.ndarray, torch.Tensor]
Returns

The number of solver iterations for positions for each particle system. shape is (M, ).

Return type

Union[np.ndarray, torch.Tensor]

Parameters

indices (Optional[Union[np.ndarray, list, torch.Tensor]], optional) – indices to specify which prims to query. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view)

get_winds(indices: Optional[Union[numpy.ndarray, list, torch.Tensor]] = None, clone: bool = True) Union[numpy.ndarray, torch.Tensor]
Returns

The winds applied to the current particle system. shape is (M, 3).

Return type

Union[np.ndarray, torch.Tensor]

Parameters
  • indices (Optional[Union[np.ndarray, list, torch.Tensor]], optional) – indices to specify which prims to query. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view)

  • clone (bool, optional) – True to return a clone of the internal buffer. Otherwise False. Defaults to True.

initialize(physics_sim_view: Optional[omni.physics.tensors.bindings._physicsTensors.SimulationView] = None) None

Create a physics simulation view if not passed and creates a Particle System View.

Parameters

physics_sim_view (omni.physics.tensors.SimulationView, optional) – current physics simulation view. Defaults to None.

is_physics_handle_valid() bool
Returns

True if the physics handle of the view is valid (i.e physics is initialized for the view). Otherwise False.

Return type

bool

is_valid(indices: Optional[Union[numpy.ndarray, list, torch.Tensor]] = None) bool
Parameters

indices (Optional[Union[np.ndarray, list, torch.Tensor]], optional) – indices to specify which prims to query. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

Returns

True if all prim paths specified in the view correspond to a valid prim in stage. False otherwise.

Return type

bool

property name: str

Returns: str: name given to the view when instantiating it.

post_reset() None

Resets the particles to their initial states.

set_contact_offsets(values: Union[numpy.ndarray, torch.Tensor], indices: Optional[Union[numpy.ndarray, List, torch.Tensor]] = None) None

Set the contact offset used for collisions with non-particle objects such as rigid or deformable bodies for particle systems.

Parameters
  • values (Optional[Union[np.ndarray, torch.Tensor]]) – maximum particle velocity tensor to set particle systems to. shape is (M, ).

  • indices (Optional[Union[np.ndarray, list, torch.Tensor]], optional) – indices to specify which prims to manipulate. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

set_enable_ccds(values: Union[numpy.ndarray, torch.Tensor], indices: Optional[Union[numpy.ndarray, List, torch.Tensor]] = None) None

Enable continuous collision detection for particles for particle systems.

Parameters
  • values (Optional[Union[np.ndarray, torch.Tensor]]) – maximum particle velocity tensor to set particle systems to. shape is (M, ).

  • indices (Optional[Union[np.ndarray, list, torch.Tensor]], optional) – indices to specify which prims to manipulate. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

set_fluid_rest_offsets(values: Union[numpy.ndarray, torch.Tensor], indices: Optional[Union[numpy.ndarray, List, torch.Tensor]] = None) None

Set the rest offset used for fluid-fluid particle interactions.

Note: Must be smaller than particle contact offset.

Parameters
  • values (Optional[Union[np.ndarray, torch.Tensor]]) – fluid rest offset to set particle systems to. shape is (M, ).

  • indices (Optional[Union[np.ndarray, list, torch.Tensor]], optional) – indices to specify which prims to manipulate. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

set_global_self_collisions_enabled(values: Union[numpy.ndarray, torch.Tensor], indices: Optional[Union[numpy.ndarray, List, torch.Tensor]] = None) None

Enable self collisions to follow particle-object-specific settings for particle systems.

Parameters
  • values (Optional[Union[np.ndarray, torch.Tensor]]) – maximum particle velocity tensor to set particle systems to. shape is (M, ).

  • indices (Optional[Union[np.ndarray, list, torch.Tensor]], optional) – indices to specify which prims to manipulate. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

set_max_depenetration_velocities(values: Union[numpy.ndarray, torch.Tensor], indices: Optional[Union[numpy.ndarray, List, torch.Tensor]] = None) None

Set the maximum velocity permitted to be introduced by the solver to depenetrate intersecting particles for particle systems.

Parameters
  • values (Optional[Union[np.ndarray, torch.Tensor]]) – maximum particle velocity tensor to set particle systems to. shape is (M, ).

  • indices (Optional[Union[np.ndarray, list, torch.Tensor]], optional) – indices to specify which prims to manipulate. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

set_max_neighborhoods(values: Union[numpy.ndarray, torch.Tensor], indices: Optional[Union[numpy.ndarray, List, torch.Tensor]] = None) None

Set the particle neighborhood size for particle systems.

Parameters
  • values (Optional[Union[np.ndarray, torch.Tensor]]) – maximum particle velocity tensor to set particle systems to. shape is (M, ).

  • indices (Optional[Union[np.ndarray, list, torch.Tensor]], optional) – indices to specify which prims to manipulate. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

set_max_velocities(values: Union[numpy.ndarray, torch.Tensor], indices: Optional[Union[numpy.ndarray, List, torch.Tensor]] = None) None

Set the maximum particle velocity for particle systems.

Parameters
  • values (Optional[Union[np.ndarray, torch.Tensor]]) – maximum particle velocity tensor to set particle systems to. shape is (M, ).

  • indices (Optional[Union[np.ndarray, list, torch.Tensor]], optional) – indices to specify which prims to manipulate. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

set_particle_contact_offsets(values: Union[numpy.ndarray, torch.Tensor], indices: Optional[Union[numpy.ndarray, List, torch.Tensor]] = None) None

Set the contact offset used for interactions between particles.

Note: Must be larger than solid and fluid rest offsets.

Parameters
  • values (Optional[Union[np.ndarray, torch.Tensor]]) – The contact offset.

  • indices (Optional[Union[np.ndarray, list, torch.Tensor]], optional) – indices to specify which prims to manipulate. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

set_particle_systems_enabled(values: Union[numpy.ndarray, torch.Tensor], indices: Optional[Union[numpy.ndarray, List, torch.Tensor]] = None) None

Set enabling of the particle systems.

Parameters
  • values (Optional[Union[np.ndarray, torch.Tensor]]) – maximum particle velocity tensor to set particle systems to. shape is (M, ).

  • indices (Optional[Union[np.ndarray, list, torch.Tensor]], optional) – indices to specify which prims to manipulate. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

set_rest_offsets(values: Union[numpy.ndarray, torch.Tensor], indices: Optional[Union[numpy.ndarray, List, torch.Tensor]] = None) None

Set the rest offset used for collisions with non-particle objects such as rigid or deformable bodies for particle systems.

Parameters
  • values (Optional[Union[np.ndarray, torch.Tensor]]) – maximum particle velocity tensor to set particle systems to. shape is (M, ).

  • indices (Optional[Union[np.ndarray, list, torch.Tensor]], optional) – indices to specify which prims to manipulate. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

set_simulation_owners(values: Sequence[str], indices: Optional[Union[numpy.ndarray, List, torch.Tensor]] = None) None

Set the PhysicsScene that simulates particle systems.

Parameters
  • values (Sequence[str]) – PhysicsScene list to set particle systems to. shape is (M, ).

  • indices (Optional[Union[np.ndarray, list, torch.Tensor]], optional) – indices to specify which prims to manipulate. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

set_solid_rest_offsets(values: Union[numpy.ndarray, torch.Tensor], indices: Optional[Union[numpy.ndarray, List, torch.Tensor]] = None) None

Set the rest offset used for solid-solid or solid-fluid particle interactions.

Note: Must be smaller than particle contact offset.

Parameters
  • values (Optional[Union[np.ndarray, torch.Tensor]]) – solid rest offset to set particle systems to. shape is (M, ).

  • indices (Optional[Union[np.ndarray, list, torch.Tensor]], optional) – indices to specify which prims to manipulate. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

set_solver_position_iteration_counts(values: Union[numpy.ndarray, torch.Tensor], indices: Optional[Union[numpy.ndarray, List, torch.Tensor]] = None) None

Set the number of solver iterations for position for particle systems.

Parameters
  • values (Optional[Union[np.ndarray, torch.Tensor]]) – maximum particle velocity tensor to set particle systems to. shape is (M, ).

  • indices (Optional[Union[np.ndarray, list, torch.Tensor]], optional) – indices to specify which prims to manipulate. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

set_winds(values: Union[numpy.ndarray, torch.Tensor], indices: Optional[Union[numpy.ndarray, List, torch.Tensor]] = None) None

Set the winds velocities applied to the current particle system.

Parameters
  • values (Optional[Union[np.ndarray, torch.Tensor]]) – The wind applied to the current particle system. shape is (M, 3).

  • indices (Optional[Union[np.ndarray, list, torch.Tensor]], optional) – indices to specify which prims to manipulate. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

Robots

Robot

class Robot(prim_path: str, name: str = 'robot', position: Optional[Sequence[float]] = None, translation: Optional[Sequence[float]] = None, orientation: Optional[Sequence[float]] = None, scale: Optional[Sequence[float]] = None, visible: bool = True, articulation_controller: Optional[omni.isaac.core.controllers.articulation_controller.ArticulationController] = None)

Implementation (on Articulation class) to deal with an articulation prim as a robot

Warning

The robot (articulation) object must be initialized in order to be able to operate on it. See the initialize method for more details.

Parameters
  • prim_path (str) – prim path of the Prim to encapsulate or create.

  • name (str, optional) – shortname to be used as a key by Scene class. Note: needs to be unique if the object is added to the Scene. Defaults to “robot”.

  • position (Optional[Sequence[float]], optional) – position in the world frame of the prim. shape is (3, ). Defaults to None, which means left unchanged.

  • translation (Optional[Sequence[float]], optional) – translation in the local frame of the prim (with respect to its parent prim). shape is (3, ). Defaults to None, which means left unchanged.

  • orientation (Optional[Sequence[float]], optional) – quaternion orientation in the world/ local frame of the prim (depends if translation or position is specified). quaternion is scalar-first (w, x, y, z). shape is (4, ). Defaults to None, which means left unchanged.

  • scale (Optional[Sequence[float]], optional) – local scale to be applied to the prim’s dimensions. shape is (3, ). Defaults to None, which means left unchanged.

  • visible (bool, optional) – set to false for an invisible prim in the stage while rendering. Defaults to True.

  • articulation_controller (Optional[ArticulationController], optional) – a custom ArticulationController which inherits from it. Defaults to creating the basic ArticulationController.

Example:

>>> import omni.isaac.core.utils.stage as stage_utils
>>> from omni.isaac.core.robots import Robot
>>>
>>> usd_path = "/home/<user>/Documents/Assets/Robots/Franka/franka_alt_fingers.usd"
>>> prim_path = "/World/envs/env_0/panda"
>>>
>>> # load the Franka Panda robot USD file
>>> stage_utils.add_reference_to_stage(usd_path, prim_path)
>>>
>>> # wrap the prim as a robot (articulation)
>>> prim = Robot(prim_path=prim_path, name="franka_panda")
>>> print(prim)
<omni.isaac.core.robots.robot.Robot object at 0x7fdd4875a1d0>
apply_action(control_actions: omni.isaac.core.utils.types.ArticulationAction) None

Apply joint positions, velocities and/or efforts to control an articulation

Parameters
  • control_actions (ArticulationAction) – actions to be applied for next physics step.

  • indices (Optional[Union[list, np.ndarray]], optional) – degree of freedom indices to apply actions to. Defaults to all degrees of freedom.

Hint

High stiffness makes the joints snap faster and harder to the desired target, and higher damping smoothes but also slows down the joint’s movement to target

  • For position control, set relatively high stiffness and low damping (to reduce vibrations)

  • For velocity control, stiffness must be set to zero with a non-zero damping

  • For effort control, stiffness and damping must be set to zero

Example:

>>> from omni.isaac.core.utils.types import ArticulationAction
>>>
>>> # move all the robot joints to the indicated position
>>> action = ArticulationAction(joint_positions=np.array([0.0, -1.0, 0.0, -2.2, 0.0, 2.4, 0.8, 0.04, 0.04]))
>>> prim.apply_action(action)
>>>
>>> # close the robot fingers: panda_finger_joint1 (7) and panda_finger_joint2 (8) to 0.0
>>> action = ArticulationAction(joint_positions=np.array([0.0, 0.0]), joint_indices=np.array([7, 8]))
>>> prim.apply_action(action)
apply_visual_material(visual_material: omni.isaac.core.materials.visual_material.VisualMaterial, weaker_than_descendants: bool = False) None

Apply visual material to the held prim and optionally its descendants.

Parameters
  • visual_material (VisualMaterial) – visual material to be applied to the held prim. Currently supports PreviewSurface, OmniPBR and OmniGlass.

  • weaker_than_descendants (bool, optional) – True if the material shouldn’t override the descendants materials, otherwise False. Defaults to False.

Example:

>>> from omni.isaac.core.materials import OmniGlass
>>>
>>> # create a dark-red glass visual material
>>> material = OmniGlass(
...     prim_path="/World/material/glass",  # path to the material prim to create
...     ior=1.25,
...     depth=0.001,
...     thin_walled=False,
...     color=np.array([0.5, 0.0, 0.0])
... )
>>> prim.apply_visual_material(material)
property articulation_handle: int

A handler to the articulation

The handler is a unique identifier used by the Dynamic Control extension to manage the articulation

Returns

handle

Return type

int

Example:

>>> prim.articulation_handle
1116691496961
disable_gravity() None

Keep gravity from affecting the robot

Example:

>>> prim.disable_gravity()
property dof_names: List[str]

List of prim names for each DOF.

Returns

prim names

Return type

list(string)

Example:

>>> prim.dof_names
['panda_joint1', 'panda_joint2', 'panda_joint3', 'panda_joint4', 'panda_joint5',
 'panda_joint6', 'panda_joint7', 'panda_finger_joint1', 'panda_finger_joint2']
property dof_properties: numpy.ndarray

Articulation DOF properties

DOF properties

Index

Property name

Description

0

type

DOF type: invalid/unknown/uninitialized (0), rotation (1), translation (2)

1

hasLimits

Whether the DOF has limits

2

lower

Lower DOF limit (in radians or meters)

3

upper

Upper DOF limit (in radians or meters)

4

driveMode

Drive mode for the DOF: force (1), acceleration (2)

5

maxVelocity

Maximum DOF velocity. In radians/s, or stage_units/s

6

maxEffort

Maximum DOF effort. In N or N*stage_units

7

stiffness

DOF stiffness

8

damping

DOF damping

Returns

named NumPy array of shape (num_dof, 9)

Return type

np.ndarray

Example:

>>> # get properties for all DOFs
>>> prim.dof_properties
[(1,  True, -2.8973,  2.8973, 1, 1.0000000e+01, 5220., 60000., 3000.)
 (1,  True, -1.7628,  1.7628, 1, 1.0000000e+01, 5220., 60000., 3000.)
 (1,  True, -2.8973,  2.8973, 1, 5.9390470e+36, 5220., 60000., 3000.)
 (1,  True, -3.0718, -0.0698, 1, 5.9390470e+36, 5220., 60000., 3000.)
 (1,  True, -2.8973,  2.8973, 1, 5.9390470e+36,  720., 25000., 3000.)
 (1,  True, -0.0175,  3.7525, 1, 5.9390470e+36,  720., 15000., 3000.)
 (1,  True, -2.8973,  2.8973, 1, 1.0000000e+01,  720.,  5000., 3000.)
 (2,  True,  0.    ,  0.04  , 1, 3.4028235e+38,  720.,  6000., 1000.)
 (2,  True,  0.    ,  0.04  , 1, 3.4028235e+38,  720.,  6000., 1000.)]
>>>
>>> # property names
>>> prim.dof_properties.dtype.names
('type', 'hasLimits', 'lower', 'upper', 'driveMode', 'maxVelocity', 'maxEffort', 'stiffness', 'damping')
>>>
>>> # get DOF upper limits
>>> prim.dof_properties["upper"]
[ 2.8973  1.7628  2.8973 -0.0698  2.8973  3.7525  2.8973  0.04    0.04  ]
>>>
>>> # get the last DOF (panda_finger_joint2) upper limit
>>> prim.dof_properties["upper"][8]  # or prim.dof_properties[8][3]
0.04
enable_gravity() None

Gravity will affect the robot

Example:

>>> prim.enable_gravity()
get_angular_velocity() numpy.ndarray

Get the angular velocity of the root articulation prim

Returns

3D angular velocity vector. Shape (3,)

Return type

np.ndarray

Example:

>>> prim.get_angular_velocity()
[0. 0. 0.]
get_applied_action() omni.isaac.core.utils.types.ArticulationAction

Get the last applied action

Returns

last applied action. Note: a dictionary is used as the object’s string representation

Return type

ArticulationAction

Example:

>>> # last applied action: joint_positions -> [0.0, -1.0, 0.0, -2.2, 0.0, 2.4, 0.8, 0.04, 0.04]
>>> prim.get_applied_action()
{'joint_positions': [0.0, -1.0, 0.0, -2.200000047683716, 0.0, 2.4000000953674316,
                     0.800000011920929, 0.03999999910593033, 0.03999999910593033],
 'joint_velocities': [0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0],
 'joint_efforts': [0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0]}
get_applied_joint_efforts(joint_indices: Optional[Union[List, numpy.ndarray]] = None) numpy.ndarray

Get the efforts applied to the joints set by the set_joint_efforts method

Parameters

joint_indices (Optional[Union[List, np.ndarray]], optional) – indices to specify which joints to read. Defaults to None (all joints)

Raises

Exception – If the handlers are not initialized

Returns

all or selected articulation joint applied efforts

Return type

np.ndarray

Example:

>>> # get all applied joint efforts
>>> prim.get_applied_joint_efforts()
[ 0.  0.  0.  0.  0.  0.  0.  0.  0.]
>>>
>>> # get finger applied efforts: panda_finger_joint1 (7) and panda_finger_joint2 (8)
>>> prim.get_applied_joint_efforts(joint_indices=np.array([7, 8]))
[0.  0.]
get_applied_visual_material() omni.isaac.core.materials.visual_material.VisualMaterial

Return the current applied visual material in case it was applied using apply_visual_material or it’s one of the following materials that was already applied before: PreviewSurface, OmniPBR and OmniGlass.

Returns

the current applied visual material if its type is currently supported.

Return type

VisualMaterial

Example:

>>> # given a visual material applied
>>> prim.get_applied_visual_material()
<omni.isaac.core.materials.omni_glass.OmniGlass object at 0x7f36263106a0>
get_articulation_body_count() int

Get the number of bodies (links) that make up the articulation

Returns

amount of bodies

Return type

int

Example:

>>> prim.get_articulation_body_count()
12
get_articulation_controller() omni.isaac.core.controllers.articulation_controller.ArticulationController

Get the articulation controller

Note

If no articulation_controller was passed during class instantiation, a default controller of type ArticulationController (a Proportional-Derivative controller that can apply position targets, velocity targets and efforts) will be used

Returns

articulation controller

Return type

ArticulationController

Example:

>>> prim.get_articulation_controller()
<omni.isaac.core.controllers.articulation_controller.ArticulationController object at 0x7f04a0060190>
get_default_state() omni.isaac.core.utils.types.XFormPrimState

Get the default prim states (spatial position and orientation).

Returns

an object that contains the default state of the prim (position and orientation)

Return type

XFormPrimState

Example:

>>> state = prim.get_default_state()
>>> state
<omni.isaac.core.utils.types.XFormPrimState object at 0x7f33addda650>
>>>
>>> state.position
[-4.5299529e-08 -1.8347054e-09 -2.8610229e-08]
>>> state.orientation
[1. 0. 0. 0.]
get_dof_index(dof_name: str) int

Get a DOF index given its name

Parameters

dof_name (str) – name of the DOF

Returns

DOF index

Return type

int

Example:

>>> prim.get_dof_index("panda_finger_joint2")
8
get_enabled_self_collisions() int

Get the enable self collisions flag (physxArticulation:enabledSelfCollisions)

Returns

self collisions flag (boolean interpreted as int)

Return type

int

Example:

>>> prim.get_enabled_self_collisions()
0
get_joint_positions(joint_indices: Optional[Union[List, numpy.ndarray]] = None) numpy.ndarray

Get the articulation joint positions

Parameters

joint_indices (Optional[Union[List, np.ndarray]], optional) – indices to specify which joints to read. Defaults to None (all joints)

Returns

all or selected articulation joint positions

Return type

np.ndarray

Example:

>>> # get all joint positions
>>> prim.get_joint_positions()
[ 1.1999920e-02 -5.6962633e-01  1.3480479e-08 -2.8105433e+00  6.8284894e-06
  3.0301569e+00  7.3234749e-01  3.9912373e-02  3.9999999e-02]
>>>
>>> # get finger positions: panda_finger_joint1 (7) and panda_finger_joint2 (8)
>>> prim.get_joint_positions(joint_indices=np.array([7, 8]))
[0.03991237  3.9999999e-02]
get_joint_velocities(joint_indices: Optional[Union[List, numpy.ndarray]] = None) numpy.ndarray

Get the articulation joint velocities

Parameters

joint_indices (Optional[Union[List, np.ndarray]], optional) – indices to specify which joints to read. Defaults to None (all joints)

Returns

all or selected articulation joint velocities

Return type

np.ndarray

Example:

>>> # get all joint velocities
>>> prim.get_joint_velocities()
[ 1.91603772e-06 -7.67638255e-03 -2.19138826e-07  1.10636465e-02 -4.63412944e-05
  3.48245539e-02  8.84692147e-02  5.40335372e-04 1.02849208e-05]
>>>
>>> # get finger velocities: panda_finger_joint1 (7) and panda_finger_joint2 (8)
>>> prim.get_joint_velocities(joint_indices=np.array([7, 8]))
[5.4033537e-04 1.0284921e-05]
get_joints_default_state() omni.isaac.core.utils.types.JointsState

Get the default joint states (positions and velocities).

Returns

an object that contains the default joint positions and velocities

Return type

JointsState

Example:

>>> state = prim.get_joints_default_state()
>>> state
<omni.isaac.core.utils.types.JointsState object at 0x7f04a0061240>
>>>
>>> state.positions
[ 0.012  -0.57000005  0.  -2.81  0.  3.037  0.785398  0.04  0.04 ]
>>> state.velocities
[0. 0. 0. 0. 0. 0. 0. 0. 0.]
get_joints_state() omni.isaac.core.utils.types.JointsState

Get the current joint states (positions and velocities)

Returns

an object that contains the current joint positions and velocities

Return type

JointsState

Example:

>>> state = prim.get_joints_state()
>>> state
<omni.isaac.core.utils.types.JointsState object at 0x7f02f6df57b0>
>>>
>>> state.positions
[ 1.1999920e-02 -5.6962633e-01  1.3480479e-08 -2.8105433e+00 6.8284894e-06
  3.0301569e+00  7.3234749e-01  3.9912373e-02  3.9999999e-02]
>>> state.velocities
[ 1.91603772e-06 -7.67638255e-03 -2.19138826e-07  1.10636465e-02 -4.63412944e-05
  245539e-02  8.84692147e-02  5.40335372e-04  1.02849208e-05]
get_linear_velocity() numpy.ndarray

Get the linear velocity of the root articulation prim

Returns

3D linear velocity vector. Shape (3,)

Return type

np.ndarray

Example:

>>> prim.get_linear_velocity()
[0. 0. 0.]
get_local_pose() Tuple[numpy.ndarray, numpy.ndarray]

Get prim’s pose with respect to the local frame (the prim’s parent frame)

Returns

first index is the position in the local frame (with shape (3, )). Second index is quaternion orientation (with shape (4, )) in the local frame

Return type

Tuple[np.ndarray, np.ndarray]

Example:

>>> # if the prim is in position (1.0, 0.5, 0.0) with respect to the world frame
>>> position, orientation = prim.get_local_pose()
>>> position
[0. 0. 0.]
>>> orientation
[0. 0. 0.]
get_local_scale() numpy.ndarray

Get prim’s scale with respect to the local frame (the parent’s frame)

Returns

scale applied to the prim’s dimensions in the local frame. shape is (3, ).

Return type

np.ndarray

Example:

>>> prim.get_local_scale()
[1. 1. 1.]
get_measured_joint_efforts(joint_indices: Optional[Union[List, numpy.ndarray]] = None) numpy.ndarray

Returns the efforts computed/measured by the physics solver of the joint forces in the DOF motion direction

Parameters

joint_indices (Optional[Union[List, np.ndarray]], optional) – indices to specify which joints to read. Defaults to None (all joints)

Raises

Exception – If the handlers are not initialized

Returns

all or selected articulation joint measured efforts

Return type

np.ndarray

Example:

>>> # get all joint efforts
>>> prim.get_measured_joint_efforts()
[ 2.7897308e-06 -6.9083519e+00 -3.6398471e-06  1.9158335e+01 -4.3552645e-06
  1.1866090e+00 -4.7079347e-06  3.2339853e-04 -3.2044132e-04]
>>>
>>> # get finger efforts: panda_finger_joint1 (7) and panda_finger_joint2 (8)
>>> prim.get_measured_joint_efforts(joint_indices=np.array([7, 8]))
[ 0.0003234  -0.00032044]
get_measured_joint_forces(joint_indices: Optional[Union[List, numpy.ndarray]] = None) numpy.ndarray

Get the measured joint reaction forces and torques (link incoming joint forces and torques) to external loads

Note

Since the name->index map for joints has not been exposed yet, it is possible to access the joint names and their indices through the articulation metadata.

prim._articulation_view._metadata.joint_names  # list of names
prim._articulation_view._metadata.joint_indices  # dict of name: index

To retrieve a specific row for the link incoming joint force/torque use joint_index + 1

Parameters

joint_indices (Optional[Union[List, np.ndarray]], optional) – indices to specify which joints to read. Defaults to None (all joints)

Raises

Exception – If the handlers are not initialized

Returns

measured joint forces and torques. Shape is (num_joint + 1, 6). Row index 0 is the incoming joint of the base link. For the last dimension the first 3 values are for forces and the last 3 for torques

Return type

np.ndarray

Example:

>>> # get all measured joint forces and torques
>>> prim.get_measured_joint_forces()
[[ 0.0000000e+00  0.0000000e+00  0.0000000e+00  0.0000000e+00  0.0000000e+00  0.0000000e+00]
 [ 1.4995076e+02  4.2574748e-06  5.6364370e-04  4.8701895e-05 -6.9072924e+00  3.1881387e-05]
 [-2.8971717e-05 -1.0677823e+02 -6.8384506e+01 -6.9072924e+00 -5.4927128e-05  6.1222494e-07]
 [ 8.7120995e+01 -4.3871860e-05 -5.5795174e+01  5.3687054e-05 -2.4538563e+01  1.3333466e-05]
 [ 5.3519474e-05 -4.8109909e+01  6.0709282e+01  1.9157074e+01 -5.9258469e-05  8.2744418e-07]
 [-3.1691040e+01  2.3313689e-04  3.9990173e+01 -5.8968733e-05 -1.1863431e+00  2.2335558e-05]
 [-1.0809851e-04  1.5340537e+01 -1.5458489e+01  1.1863426e+00  6.1094368e-05 -1.5940281e-05]
 [-7.5418940e+00 -5.0814648e+00 -5.6512990e+00 -5.6385466e-05  3.8859999e-01 -3.4943256e-01]
 [ 4.7421460e+00 -3.1945827e+00  3.5528181e+00  5.5852943e-05  8.4794536e-03  7.6405057e-03]
 [ 4.0760727e+00  2.1640673e-01 -4.0513167e+00 -5.9565349e-04  1.1407082e-02  2.1432268e-06]
 [ 5.1680198e-03 -9.7754575e-02 -9.7093947e-02 -8.4155556e-12 -1.2910691e-12 -1.9347857e-11]
 [-5.1910793e-03  9.7588278e-02 -9.7106412e-02  8.4155573e-12  1.2910637e-12 -1.9347855e-11]]
>>>
>>> # get measured joint force and torque for the fingers
>>> metadata = prim._articulation_view._metadata
>>> joint_indices = 1 + np.array([
...     metadata.joint_indices["panda_finger_joint1"],
...     metadata.joint_indices["panda_finger_joint2"],
... ])
>>> joint_indices
[10 11]
>>> prim.get_measured_joint_forces(joint_indices)
[[ 5.1680198e-03 -9.7754575e-02 -9.7093947e-02 -8.4155556e-12 -1.2910691e-12 -1.9347857e-11]
 [-5.1910793e-03  9.7588278e-02 -9.7106412e-02  8.4155573e-12  1.2910637e-12 -1.9347855e-11]]
get_sleep_threshold() float

Get the threshold for articulations to enter a sleep state

Search for Articulations and Sleeping in PhysX docs for more details

Returns

sleep threshold

Return type

float

Example:

>>> prim.get_sleep_threshold()
0.005
get_solver_position_iteration_count() int

Get the solver (position) iteration count for the articulation

The solver iteration count determines how accurately contacts, drives, and limits are resolved. Search for Solver Iteration Count in PhysX docs for more details.

Returns

position iteration count

Return type

int

Example:

>>> prim.get_solver_position_iteration_count()
32
get_solver_velocity_iteration_count() int

Get the solver (velocity) iteration count for the articulation

The solver iteration count determines how accurately contacts, drives, and limits are resolved. Search for Solver Iteration Count in PhysX docs for more details.

Returns

velocity iteration count

Return type

int

Example:

>>> prim.get_solver_velocity_iteration_count()
32
get_stabilization_threshold() float

Get the mass-normalized kinetic energy below which the articulation may participate in stabilization

Search for Stabilization Threshold in PhysX docs for more details

Returns

stabilization threshold

Return type

float

Example:

>>> prim.get_stabilization_threshold()
0.0009999999
get_visibility() bool
Returns

true if the prim is visible in stage. false otherwise.

Return type

bool

Example:

>>> # get the visible state of an visible prim on the stage
>>> prim.get_visibility()
True
get_world_pose() Tuple[numpy.ndarray, numpy.ndarray]

Get prim’s pose with respect to the world’s frame

Returns

first index is the position in the world frame (with shape (3, )). Second index is quaternion orientation (with shape (4, )) in the world frame

Return type

Tuple[np.ndarray, np.ndarray]

Example:

>>> # if the prim is in position (1.0, 0.5, 0.0) with respect to the world frame
>>> position, orientation = prim.get_world_pose()
>>> position
[1.  0.5 0. ]
>>> orientation
[1. 0. 0. 0.]
get_world_scale() numpy.ndarray

Get prim’s scale with respect to the world’s frame

Returns

scale applied to the prim’s dimensions in the world frame. shape is (3, ).

Return type

np.ndarray

Example:

>>> prim.get_world_scale()
[1. 1. 1.]
property handles_initialized: bool

Check if articulation handler is initialized

Returns

whether the handler was initialized

Return type

bool

Example:

>>> prim.handles_initialized
True
initialize(physics_sim_view: Optional[omni.physics.tensors.bindings._physicsTensors.SimulationView] = None) None

Create a physics simulation view if not passed and an articulation view using PhysX tensor API

Note

If the articulation has been added to the world scene (e.g., world.scene.add(prim)), it will be automatically initialized when the world is reset (e.g., world.reset()).

Warning

This method needs to be called after each hard reset (e.g., Stop + Play on the timeline) before interacting with any other class method.

Parameters

physics_sim_view (omni.physics.tensors.SimulationView, optional) – current physics simulation view. Defaults to None.

Example:

>>> prim.initialize()
is_valid() bool

Check if the prim path has a valid USD Prim at it

Returns

True is the current prim path corresponds to a valid prim in stage. False otherwise.

Return type

bool

Example:

>>> # given an existing and valid prim
>>> prims.is_valid()
True
is_visual_material_applied() bool

Check if there is a visual material applied

Returns

True if there is a visual material applied. False otherwise.

Return type

bool

Example:

>>> # given a visual material applied
>>> prim.is_visual_material_applied()
True
property name: Optional[str]

Returns: str: name given to the prim when instantiating it. Otherwise None.

Used to query if the prim is a non root articulation link

Returns

True if the prim itself is a non root link

Return type

bool

Example:

>>> # for a wrapped articulation (where the root prim has the Physics Articulation Root property applied)
>>> prim.non_root_articulation_link
False
property num_dof: int

Number of DOF of the articulation

Returns

amount of DOFs

Return type

int

Example:

>>> prim.num_dof
9
post_reset() None

Reset the robot to its default state

Note

For a robot, in addition to configuring the root prim’s default position and spatial orientation (defined via the set_default_state method), the joint’s positions, velocities, and efforts (defined via the set_joints_default_state method) are imposed

Example:

>>> prim.post_reset()
property prim: pxr.Usd.Prim

Returns: Usd.Prim: USD Prim object that this object holds.

property prim_path: str

Returns: str: prim path in the stage

set_angular_velocity(velocity: numpy.ndarray) None

Set the angular velocity of the root articulation prim

Warning

This method will immediately set the articulation state

Parameters

velocity (np.ndarray) – 3D angular velocity vector. Shape (3,)

Hint

This method belongs to the methods used to set the articulation kinematic state:

set_linear_velocity, set_angular_velocity, set_joint_positions, set_joint_velocities, set_joint_efforts

Example:

>>> prim.set_angular_velocity(np.array([0.1, 0.0, 0.0]))
set_default_state(position: Optional[Sequence[float]] = None, orientation: Optional[Sequence[float]] = None) None

Set the default state of the prim (position and orientation), that will be used after each reset.

Parameters
  • position (Optional[Sequence[float]], optional) – position in the world frame of the prim. shape is (3, ). Defaults to None, which means left unchanged.

  • orientation (Optional[Sequence[float]], optional) – quaternion orientation in the world frame of the prim. quaternion is scalar-first (w, x, y, z). shape is (4, ). Defaults to None, which means left unchanged.

Example:

>>> # configure default state
>>> prim.set_default_state(position=np.array([1.0, 0.5, 0.0]), orientation=np.array([1, 0, 0, 0]))
>>>
>>> # set default states during post-reset
>>> prim.post_reset()
set_enabled_self_collisions(flag: bool) None

Set the enable self collisions flag (physxArticulation:enabledSelfCollisions)

Parameters

flag (bool) – whether to enable self collisions

Example:

>>> prim.set_enabled_self_collisions(True)
set_joint_efforts(efforts: numpy.ndarray, joint_indices: Optional[Union[List, numpy.ndarray]] = None) None

Set the articulation joint efforts

Note

This method can be used for effort control. For this purpose, there must be no joint drive or the stiffness and damping must be set to zero.

Parameters
  • efforts (np.ndarray) – articulation joint efforts

  • joint_indices (Optional[Union[list, np.ndarray]], optional) – indices to specify which joints to manipulate. Defaults to None (all joints)

Hint

This method belongs to the methods used to set the articulation kinematic state:

set_linear_velocity, set_angular_velocity, set_joint_positions, set_joint_velocities, set_joint_efforts

Example:

>>> # set all the robot joint efforts to 0.0
>>> prim.set_joint_efforts(np.array([0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0]))
>>>
>>> # set only the fingers efforts: panda_finger_joint1 (7) and panda_finger_joint2 (8) to 10
>>> prim.set_joint_efforts(np.array([10, 10]), joint_indices=np.array([7, 8]))
set_joint_positions(positions: numpy.ndarray, joint_indices: Optional[Union[List, numpy.ndarray]] = None) None

Set the articulation joint positions

Warning

This method will immediately set (teleport) the affected joints to the indicated value. Use the apply_action method to control robot joints.

Parameters
  • positions (np.ndarray) – articulation joint positions

  • joint_indices (Optional[Union[list, np.ndarray]], optional) – indices to specify which joints to manipulate. Defaults to None (all joints)

Hint

This method belongs to the methods used to set the articulation kinematic state:

set_linear_velocity, set_angular_velocity, set_joint_positions, set_joint_velocities, set_joint_efforts

Example:

>>> # set all the robot joints
>>> prim.set_joint_positions(np.array([0.0, -1.0, 0.0, -2.2, 0.0, 2.4, 0.8, 0.04, 0.04]))
>>>
>>> # set only the fingers in closed position: panda_finger_joint1 (7) and panda_finger_joint2 (8) to 0.0
>>> prim.set_joint_positions(np.array([0.04, 0.04]), joint_indices=np.array([7, 8]))
set_joint_velocities(velocities: numpy.ndarray, joint_indices: Optional[Union[List, numpy.ndarray]] = None) None

Set the articulation joint velocities

Warning

This method will immediately set the affected joints to the indicated value. Use the apply_action method to control robot joints.

Parameters
  • velocities (np.ndarray) – articulation joint velocities

  • joint_indices (Optional[Union[list, np.ndarray]], optional) – indices to specify which joints to manipulate. Defaults to None (all joints)

Hint

This method belongs to the methods used to set the articulation kinematic state:

set_linear_velocity, set_angular_velocity, set_joint_positions, set_joint_velocities, set_joint_efforts

Example:

>>> # set all the robot joint velocities to 0.0
>>> prim.set_joint_velocities(np.array([0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0]))
>>>
>>> # set only the fingers velocities: panda_finger_joint1 (7) and panda_finger_joint2 (8) to -0.01
>>> prim.set_joint_velocities(np.array([-0.01, -0.01]), joint_indices=np.array([7, 8]))
set_joints_default_state(positions: Optional[numpy.ndarray] = None, velocities: Optional[numpy.ndarray] = None, efforts: Optional[numpy.ndarray] = None) None

Set the joint default states (positions, velocities and/or efforts) to be applied after each reset.

Note

The default states will be set during post-reset (e.g., calling .post_reset() or world.reset() methods)

Parameters
  • positions (Optional[np.ndarray], optional) – joint positions. Defaults to None.

  • velocities (Optional[np.ndarray], optional) – joint velocities. Defaults to None.

  • efforts (Optional[np.ndarray], optional) – joint efforts. Defaults to None.

Example:

>>> # configure default joint states
>>> prim.set_joints_default_state(
...     positions=np.array([0.0, -1.0, 0.0, -2.2, 0.0, 2.4, 0.8, 0.04, 0.04]),
...     velocities=np.zeros(shape=(prim.num_dof,)),
...     efforts=np.zeros(shape=(prim.num_dof,))
... )
>>>
>>> # set default states during post-reset
>>> prim.post_reset()
set_linear_velocity(velocity: numpy.ndarray) None

Set the linear velocity of the root articulation prim

Warning

This method will immediately set the articulation state

Parameters

velocity (np.ndarray) – 3D linear velocity vector. Shape (3,).

Hint

This method belongs to the methods used to set the articulation kinematic state:

set_linear_velocity, set_angular_velocity, set_joint_positions, set_joint_velocities, set_joint_efforts

Example:

>>> prim.set_linear_velocity(np.array([0.1, 0.0, 0.0]))
set_local_pose(translation: Optional[Sequence[float]] = None, orientation: Optional[Sequence[float]] = None) None

Set prim’s pose with respect to the local frame (the prim’s parent frame).

Warning

This method will change (teleport) the prim pose immediately to the indicated value

Parameters
  • translation (Optional[Sequence[float]], optional) – translation in the local frame of the prim (with respect to its parent prim). shape is (3, ). Defaults to None, which means left unchanged.

  • orientation (Optional[Sequence[float]], optional) – quaternion orientation in the local frame of the prim. quaternion is scalar-first (w, x, y, z). shape is (4, ). Defaults to None, which means left unchanged.

Hint

This method belongs to the methods used to set the prim state

Example:

>>> prim.set_local_pose(translation=np.array([1.0, 0.5, 0.0]), orientation=np.array([1., 0., 0., 0.]))
set_local_scale(scale: Optional[Sequence[float]]) None

Set prim’s scale with respect to the local frame (the prim’s parent frame).

Parameters

scale (Optional[Sequence[float]]) – scale to be applied to the prim’s dimensions. shape is (3, ). Defaults to None, which means left unchanged.

Example:

>>> # scale prim 10 times smaller
>>> prim.set_local_scale(np.array([0.1, 0.1, 0.1]))
set_sleep_threshold(threshold: float) None

Set the threshold for articulations to enter a sleep state

Search for Articulations and Sleeping in PhysX docs for more details

Parameters

threshold (float) – sleep threshold

Example:

>>> prim.set_sleep_threshold(0.01)
set_solver_position_iteration_count(count: int) None

Set the solver (position) iteration count for the articulation

The solver iteration count determines how accurately contacts, drives, and limits are resolved. Search for Solver Iteration Count in PhysX docs for more details.

Warning

Setting a higher number of iterations may improve the fidelity of the simulation, although it may affect its performance.

Parameters

count (int) – position iteration count

Example:

>>> prim.set_solver_position_iteration_count(64)
set_solver_velocity_iteration_count(count: int)

Set the solver (velocity) iteration count for the articulation

The solver iteration count determines how accurately contacts, drives, and limits are resolved. Search for Solver Iteration Count in PhysX docs for more details.

Warning

Setting a higher number of iterations may improve the fidelity of the simulation, although it may affect its performance.

Parameters

count (int) – velocity iteration count

Example:

>>> prim.set_solver_velocity_iteration_count(64)
set_stabilization_threshold(threshold: float) None

Set the mass-normalized kinetic energy below which the articulation may participate in stabilization

Search for Stabilization Threshold in PhysX docs for more details

Parameters

threshold (float) – stabilization threshold

Example:

>>> prim.set_stabilization_threshold(0.005)
set_visibility(visible: bool) None

Set the visibility of the prim in stage

Parameters

visible (bool) – flag to set the visibility of the usd prim in stage.

Example:

>>> # make prim not visible in the stage
>>> prim.set_visibility(visible=False)
set_world_pose(position: Optional[Sequence[float]] = None, orientation: Optional[Sequence[float]] = None) None

Ses prim’s pose with respect to the world’s frame

Warning

This method will change (teleport) the prim pose immediately to the indicated value

Parameters
  • position (Optional[Sequence[float]], optional) – position in the world frame of the prim. shape is (3, ). Defaults to None, which means left unchanged.

  • orientation (Optional[Sequence[float]], optional) – quaternion orientation in the world frame of the prim. quaternion is scalar-first (w, x, y, z). shape is (4, ). Defaults to None, which means left unchanged.

Hint

This method belongs to the methods used to set the prim state

Example:

>>> prim.set_world_pose(position=np.array([1.0, 0.5, 0.0]), orientation=np.array([1., 0., 0., 0.]))

Robot View

class RobotView(prim_paths_expr: str, name: str = 'rigid_prim_view', positions: Optional[Union[numpy.ndarray, torch.Tensor]] = None, translations: Optional[Union[numpy.ndarray, torch.Tensor]] = None, orientations: Optional[Union[numpy.ndarray, torch.Tensor]] = None, scales: Optional[Union[numpy.ndarray, torch.Tensor]] = None, visibilities: Optional[Union[numpy.ndarray, torch.Tensor]] = None)

Implementation (on ArticulationView class) to deal with articulation prims as robots

This class wraps all matching articulations found at the regex provided at the prim_paths_expr argument

Warning

The robot (articulation) view object must be initialized in order to be able to operate on it. See the initialize method for more details.

Parameters
  • prim_paths_expr (str) – prim paths regex to encapsulate all prims that match it. example: “/World/Env[1-5]/Franka” will match /World/Env1/Franka, /World/Env2/Franka, etc. (a non regex prim path can also be used to encapsulate one rigid prim).

  • name (str, optional) – shortname to be used as a key by Scene class. Note: needs to be unique if the object is added to the Scene. Defaults to “rigid_prim_view”.

  • positions (Optional[Union[np.ndarray, torch.Tensor]], optional) – default positions in the world frame of the prims. shape is (N, 3). Defaults to None, which means left unchanged.

  • translations (Optional[Union[np.ndarray, torch.Tensor]], optional) – default translations in the local frame of the prims (with respect to its parent prims). shape is (N, 3). Defaults to None, which means left unchanged.

  • orientations (Optional[Union[np.ndarray, torch.Tensor]], optional) – default quaternion orientations in the world/ local frame of the prims (depends if translation or position is specified). quaternion is scalar-first (w, x, y, z). shape is (N, 4).

  • scales (Optional[Union[np.ndarray, torch.Tensor]], optional) – local scales to be applied to the prim’s dimensions in the view. shape is (N, 3). Defaults to None, which means left unchanged.

  • visibilities (Optional[Union[np.ndarray, torch.Tensor]], optional) – set to false for an invisible prim in the stage while rendering. shape is (N,). Defaults to None.

Example:

>>> import omni.isaac.core.utils.stage as stage_utils
>>> from omni.isaac.cloner import GridCloner
>>> from omni.isaac.core.robots import RobotView
>>> from pxr import UsdGeom
>>>
>>> usd_path = "/home/<user>/Documents/Assets/Robots/Franka/franka_alt_fingers.usd"
>>> env_zero_path = "/World/envs/env_0"
>>> num_envs = 5
>>>
>>> # load the Franka Panda robot USD file
>>> stage_utils.add_reference_to_stage(usd_path, prim_path=f"{env_zero_path}/panda")  # /World/envs/env_0/panda
>>>
>>> # clone the environment (num_envs)
>>> cloner = GridCloner(spacing=1.5)
>>> cloner.define_base_env(env_zero_path)
>>> UsdGeom.Xform.Define(stage_utils.get_current_stage(), env_zero_path)
>>> cloner.clone(source_prim_path=env_zero_path, prim_paths=cloner.generate_paths("/World/envs/env", num_envs))
>>>
>>> # wrap all robots
>>> prims = RobotView(prim_paths_expr="/World/envs/env.*/panda", name="franka_panda_view")
>>> print(prims)
<omni.isaac.core.robots.robot_view.RobotView object at 0x7f12785a5fc0>
apply_action(control_actions: omni.isaac.core.utils.types.ArticulationActions, indices: Optional[Union[numpy.ndarray, List, torch.Tensor, warp.types.array]] = None) None

Apply joint positions (targets), velocities (targets) and/or efforts to control an articulation

Note

This method can be used instead of the separate set_joint_position_targets, set_joint_velocity_targets and set_joint_efforts

Parameters
  • control_actions (ArticulationActions) – actions to be applied for next physics step.

  • indices (Optional[Union[np.ndarray, List, torch.Tensor, wp.array]], optional) – indices to specify which prims to manipulate. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

Hint

High stiffness makes the joints snap faster and harder to the desired target, and higher damping smoothes but also slows down the joint’s movement to target

  • For position control, set relatively high stiffness and low damping (to reduce vibrations)

  • For velocity control, stiffness must be set to zero with a non-zero damping

  • For effort control, stiffness and damping must be set to zero

Example:

>>> from omni.isaac.core.utils.types import ArticulationActions
>>>
>>> # move all the articulation joints to the indicated position.
>>> # Since there are 5 envs, the joint positions are repeated 5 times
>>> positions = np.tile(np.array([0.0, -1.0, 0.0, -2.2, 0.0, 2.4, 0.8, 0.04, 0.04]), (num_envs, 1))
>>> action = ArticulationActions(joint_positions=positions)
>>> prims.apply_action(action)
>>>
>>> # close the robot fingers: panda_finger_joint1 (7) and panda_finger_joint2 (8) to 0.0
>>> # for the first, middle and last of the 5 envs
>>> positions = np.tile(np.array([0.0, 0.0]), (3, 1))
>>> action = ArticulationActions(joint_positions=positions, joint_indices=np.array([7, 8]))
>>> prims.apply_action(action, indices=np.array([0, 2, 4]))
apply_visual_materials(visual_materials: Union[omni.isaac.core.materials.visual_material.VisualMaterial, List[omni.isaac.core.materials.visual_material.VisualMaterial]], weaker_than_descendants: Optional[Union[bool, List[bool]]] = None, indices: Optional[Union[numpy.ndarray, list, torch.Tensor, warp.types.array]] = None) None

Apply visual material to the prims and optionally their prim descendants.

Parameters
  • visual_materials (Union[VisualMaterial, List[VisualMaterial]]) – visual materials to be applied to the prims. Currently supports PreviewSurface, OmniPBR and OmniGlass. If a list is provided then its size has to be equal the view’s size or indices size. If one material is provided it will be applied to all prims in the view.

  • weaker_than_descendants (Optional[Union[bool, List[bool]]], optional) – True if the material shouldn’t override the descendants materials, otherwise False. Defaults to False. If a list of visual materials is provided then a list has to be provided with the same size for this arg as well.

  • indices (Optional[Union[np.ndarray, list, torch.Tensor, wp.array]], optional) – indices to specify which prims to manipulate. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

Raises
  • Exception – length of visual materials != length of prims indexed

  • Exception – length of visual materials != length of weaker descendants bools arg

Example:

>>> from omni.isaac.core.materials import OmniGlass
>>>
>>> # create a dark-red glass visual material
>>> material = OmniGlass(
...     prim_path="/World/material/glass",  # path to the material prim to create
...     ior=1.25,
...     depth=0.001,
...     thin_walled=False,
...     color=np.array([0.5, 0.0, 0.0])
... )
>>> prims.apply_visual_materials(material)
property body_names: List[str]

List of prim names for each rigid body (link) of the articulations

Returns

ordered names of bodies that corresponds to links for the articulations in the view

Return type

List[str]

Example:

>>> prims.body_names
['panda_link0', 'panda_link1', 'panda_link2', 'panda_link3', 'panda_link4', 'panda_link5',
 'panda_link6', 'panda_link7', 'panda_link8', 'panda_hand', 'panda_leftfinger', 'panda_rightfinger']
property count: int
Returns

Number of prims encapsulated in this view.

Return type

int

Example:

>>> prims.count
5
property dof_names: List[str]

List of prim names for each DOF of the articulations

Returns

ordered names of joints that corresponds to degrees of freedom for the articulations in the view

Return type

List[str]

Example:

>>> prims.dof_names
['panda_joint1', 'panda_joint2', 'panda_joint3', 'panda_joint4', 'panda_joint5',
 'panda_joint6', 'panda_joint7', 'panda_finger_joint1', 'panda_finger_joint2']
get_angular_velocities(indices: Optional[Union[numpy.ndarray, list, torch.Tensor, warp.types.array]] = None, clone: bool = True) Union[numpy.ndarray, torch.Tensor, warp.types.indexedarray]

Get the angular velocities of prims in the view.

Parameters
  • indices (Optional[Union[np.ndarray, list, torch.Tensor, wp.array]], optional) – indices to specify which prims to query. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view)

  • clone (bool, optional) – True to return a clone of the internal buffer. Otherwise False. Defaults to True.

Returns

angular velocities of the prims in the view. shape is (M, 3).

Return type

Union[np.ndarray, torch.Tensor, wp.indexedarray]

Example:

>>> # get all articulation angular velocities. Returned shape is (5, 3) for the example: 5 envs, angular (3)
>>> prims.get_angular_velocities()
[[0. 0. 0.]
 [0. 0. 0.]
 [0. 0. 0.]
 [0. 0. 0.]
 [0. 0. 0.]]
>>>
>>> # get only the articulation angular velocities for the first, middle and last of the 5 envs
>>> # Returned shape is (5, 3) for the example: 3 envs selected, angular (3)
>>> prims.get_angular_velocities(indices=np.array([0, 2, 4]))
[[0. 0. 0.]
 [0. 0. 0.]
 [0. 0. 0.]]
get_applied_actions(clone: bool = True) omni.isaac.core.utils.types.ArticulationActions

Get the last applied actions

Parameters

clone (bool, optional) – True to return clones of the internal buffers. Otherwise False. Defaults to True.

Returns

current applied actions (i.e: current position targets and velocity targets)

Return type

ArticulationActions

Example:

>>> # last applied action: joint_positions -> [0.0, -1.0, 0.0, -2.2, 0.0, 2.4, 0.8, 0.04, 0.04].
>>> # Returned shape is (5, 9) for the example: 5 envs, 9 DOFs
>>> actions = prims.get_applied_actions()
>>> actions
<omni.isaac.core.utils.types.ArticulationActions object at 0x7f28af31d870>
>>> actions.joint_positions
[[ 0.   -1.    0.   -2.2   0.    2.4   0.8   0.04  0.04]
 [ 0.   -1.    0.   -2.2   0.    2.4   0.8   0.04  0.04]
 [ 0.   -1.    0.   -2.2   0.    2.4   0.8   0.04  0.04]
 [ 0.   -1.    0.   -2.2   0.    2.4   0.8   0.04  0.04]
 [ 0.   -1.    0.   -2.2   0.    2.4   0.8   0.04  0.04]]
>>> actions.joint_velocities
[[0. 0. 0. 0. 0. 0. 0. 0. 0.]
 [0. 0. 0. 0. 0. 0. 0. 0. 0.]
 [0. 0. 0. 0. 0. 0. 0. 0. 0.]
 [0. 0. 0. 0. 0. 0. 0. 0. 0.]
 [0. 0. 0. 0. 0. 0. 0. 0. 0.]]
>>> actions.joint_efforts
[[0. 0. 0. 0. 0. 0. 0. 0. 0.]
 [0. 0. 0. 0. 0. 0. 0. 0. 0.]
 [0. 0. 0. 0. 0. 0. 0. 0. 0.]
 [0. 0. 0. 0. 0. 0. 0. 0. 0.]
 [0. 0. 0. 0. 0. 0. 0. 0. 0.]]
get_applied_joint_efforts(indices: Optional[Union[numpy.ndarray, List, torch.Tensor, warp.types.array]] = None, joint_indices: Optional[Union[numpy.ndarray, List, torch.Tensor, warp.types.array]] = None, clone: bool = True) Union[numpy.ndarray, torch.Tensor, warp.types.indexedarray]

Get the joint efforts of articulations in the view

This method will return the efforts set by the set_joint_efforts method

Parameters
  • indices (Optional[Union[np.ndarray, List, torch.Tensor, wp.array]], optional) – indices to specify which prims to query. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

  • joint_indices (Optional[Union[np.ndarray, List, torch.Tensor, wp.array]], optional) – joint indices to specify which joints to query. Shape (K,). Where K <= num of dofs. Defaults to None (i.e: all dofs).

  • clone (bool, optional) – True to return a clone of the internal buffer. Otherwise False. Defaults to True.

Returns

joint efforts of articulations in the view. Shape is (M, K).

Return type

Union[np.ndarray, torch.Tensor, wp.indexedarray]

Example:

>>> # get all applied joint efforts. Returned shape is (5, 9) for the example: 5 envs, 9 DOFs
>>> prims.get_applied_joint_efforts()
[[0. 0. 0. 0. 0. 0. 0. 0. 0.]
 [0. 0. 0. 0. 0. 0. 0. 0. 0.]
 [0. 0. 0. 0. 0. 0. 0. 0. 0.]
 [0. 0. 0. 0. 0. 0. 0. 0. 0.]
 [0. 0. 0. 0. 0. 0. 0. 0. 0.]]
>>>
>>> # get finger applied efforts: panda_finger_joint1 (7) and panda_finger_joint2 (8)
>>> # for the first, middle and last of the 5 envs. Returned shape is (3, 2)
>>> prims.get_applied_joint_efforts(indices=np.array([0, 2, 4]), joint_indices=np.array([7, 8]))
[[0. 0.]
 [0. 0.]
 [0. 0.]]
get_applied_visual_materials(indices: Optional[Union[numpy.ndarray, list, torch.Tensor, warp.types.array]] = None) List[omni.isaac.core.materials.visual_material.VisualMaterial]

Get the current applied visual materials

Parameters

indices (Optional[Union[np.ndarray, list, torch.Tensor, wp.array]], optional) – indices to specify which prims to query. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

Returns

a list of the current applied visual materials to the prims if its type is currently supported.

Return type

List[VisualMaterial]

Example:

>>> # get all applied visual materials. Returned size is 5 for the example: 5 envs
>>> prims.get_applied_visual_materials()
[<omni.isaac.core.materials.omni_glass.OmniGlass object at 0x7f829c165de0>,
 <omni.isaac.core.materials.omni_glass.OmniGlass object at 0x7f829c165de0>,
 <omni.isaac.core.materials.omni_glass.OmniGlass object at 0x7f829c165de0>,
 <omni.isaac.core.materials.omni_glass.OmniGlass object at 0x7f829c165de0>,
 <omni.isaac.core.materials.omni_glass.OmniGlass object at 0x7f829c165de0>]
>>>
>>> # get the applied visual materials for the first, middle and last of the 5 envs. Returned size is 3
>>> prims.get_applied_visual_materials(indices=np.array([0, 2, 4]))
[<omni.isaac.core.materials.omni_glass.OmniGlass object at 0x7f829c165de0>,
 <omni.isaac.core.materials.omni_glass.OmniGlass object at 0x7f829c165de0>,
 <omni.isaac.core.materials.omni_glass.OmniGlass object at 0x7f829c165de0>]
get_armatures(indices: Optional[Union[numpy.ndarray, List, torch.Tensor, warp.types.array]] = None, joint_indices: Optional[Union[numpy.ndarray, List, torch.Tensor, warp.types.array]] = None, clone: bool = True) Union[numpy.ndarray, torch.Tensor, warp.types.indexedarray]

Get armatures for articulation joints in the view

Search for “Joint Armature” in PhysX docs for more details.

Parameters
  • indices (Optional[Union[np.ndarray, List, torch.Tensor, wp.array]], optional) – indices to specify which prims to query. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

  • joint_indices (Optional[Union[np.ndarray, List, torch.Tensor, wp.array]], optional) – joint indices to specify which joints to query. Shape (K,). Where K <= num of dofs. Defaults to None (i.e: all dofs).

  • clone (Optional[bool]) – True to return a clone of the internal buffer. Otherwise False. Defaults to True.

Returns

joint armatures for articulations in the view. shape (M, K).

Return type

Union[np.ndarray, torch.Tensor, wp.indexedarray]

Example:

>>> # get joint armatures. Returned shape is (5, 9) for the example: 5 envs, 9 DOFs
>>> prims.get_armatures()
[[0. 0. 0. 0. 0. 0. 0. 0. 0.]
 [0. 0. 0. 0. 0. 0. 0. 0. 0.]
 [0. 0. 0. 0. 0. 0. 0. 0. 0.]
 [0. 0. 0. 0. 0. 0. 0. 0. 0.]
 [0. 0. 0. 0. 0. 0. 0. 0. 0.]]
>>>
>>> # get only the finger joint (panda_finger_joint1 (7) and panda_finger_joint2 (8)) armatures
>>> # for the first, middle and last of the 5 envs. Returned shape is (3, 2)
>>> prims.get_armatures(indices=np.array([0,2,4]), joint_indices=np.array([7,8]))
[[0. 0.]
 [0. 0.]
 [0. 0.]]
get_articulation_body_count() int

Get the number of rigid bodies (links) of the articulations

Returns

maximum number of rigid bodies (links) in the articulation

Return type

int

Example:

>>> prims.get_articulation_body_count()
12
get_body_coms(indices: Optional[Union[numpy.ndarray, List, torch.Tensor, warp.types.array]] = None, body_indices: Optional[Union[numpy.ndarray, List, torch.Tensor, warp.types.array]] = None, clone: bool = True) Union[numpy.ndarray, torch.Tensor, warp.types.indexedarray]

Get rigid body center of mass (COM) of articulations in the view.

Parameters
  • indices (Optional[Union[np.ndarray, List, torch.Tensor, wp.array]], optional) – indices to specify which prims to query. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

  • body_indices (Optional[Union[np.ndarray, List, torch.Tensor, wp.array]], optional) – body indices to specify which bodies to query. Shape (K,). Where K <= num of bodies. Defaults to None (i.e: all bodies).

  • clone (bool, optional) – True to return a clone of the internal buffer. Otherwise False. Defaults to True.

Returns

rigid body center of mass positions and orientations of articulations in the view. Position shape is (M, K, 3), orientation shape is (M, k, 4).

Return type

Union[np.ndarray, torch.Tensor, wp.indexedarray]

Example:

>>> # get all body center of mass. Returned shape is (5, 12, 3) for positions and (5, 12, 4) for orientations
>>> # for the example: 5 envs, 12 rigid bodies
>>> positions, orientations = prims.get_body_coms()
>>> positions
[[[0. 0. 0.]
  [0. 0. 0.]
  ...
  [0. 0. 0.]
  [0. 0. 0.]]]
>>> orientations
[[[1. 0. 0. 0.]
  [1. 0. 0. 0.]
  ...
  [1. 0. 0. 0.]
  [1. 0. 0. 0.]]]
>>>
>>> # get finger body center of mass: panda_leftfinger (10) and panda_rightfinger (11) for the first,
>>> # middle and last of the 5 envs. Returned shape is (3, 2, 3) for positions and (3, 2, 4) for orientations
>>> positions, orientations = prims.get_body_coms(indices=np.array([0, 2, 4]), body_indices=np.array([10, 11]))
>>> positions
[[[0. 0. 0.]
  [0. 0. 0.]]
 [[0. 0. 0.]
  [0. 0. 0.]]
 [[0. 0. 0.]
  [0. 0. 0.]]]
>>> orientations
[[[1. 0. 0. 0.]
  [1. 0. 0. 0.]]
 [[1. 0. 0. 0.]
  [1. 0. 0. 0.]]
 [[1. 0. 0. 0.]
  [1. 0. 0. 0.]]]
get_body_index(body_name: str) int

Get a ridig body (link) index in the articulation view given its name

Parameters

body_name (str) – name of the ridig body to query

Returns

index of the rigid body in the articulation buffers

Return type

int

Example:

>>> # get the index of the left finger: panda_leftfinger
>>> prims.get_body_index("panda_leftfinger")
10
get_body_inertias(indices: Optional[Union[numpy.ndarray, List, torch.Tensor, warp.types.array]] = None, body_indices: Optional[Union[numpy.ndarray, List, torch.Tensor, warp.types.array]] = None, clone: bool = True) Union[numpy.ndarray, torch.Tensor, warp.types.indexedarray]

Get rigid body inertias of articulations in the view

Parameters
  • indices (Optional[Union[np.ndarray, List, torch.Tensor, wp.array]], optional) – indices to specify which prims to query. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

  • body_indices (Optional[Union[np.ndarray, List, torch.Tensor, wp.array]], optional) – body indices to specify which bodies to query. Shape (K,). Where K <= num of bodies. Defaults to None (i.e: all bodies).

  • clone (bool, optional) – True to return a clone of the internal buffer. Otherwise False. Defaults to True.

Returns

rigid body inertias of articulations in the view. Shape is (M, K, 9).

Return type

Union[np.ndarray, torch.Tensor, wp.indexedarray]

Example:

>>> # get all body inertias. Returned shape is (5, 12, 9) for the example: 5 envs, 12 rigid bodies
>>> prims.get_body_inertias()
[[[1.2988697e-06  0.0  0.0  0.0  1.6535528e-06  0.0  0.0  0.0  2.0331163e-06]
  [1.8686389e-06  0.0  0.0  0.0  1.4378986e-06  0.0  0.0  0.0  9.0681192e-07]
  ...
  [4.2041304e-10  0.0  0.0  0.0  3.9026365e-10  0.0  0.0  0.0  1.3347495e-10]
  [4.2041304e-10  0.0  0.0  0.0  3.9026365e-10  0.0  0.0  0.0  1.3347495e-10]]]
>>>
>>> # get finger body inertias: panda_leftfinger (10) and panda_rightfinger (11)
>>> # for the first, middle and last of the 5 envs. Returned shape is (3, 2, 9)
>>> prims.get_body_inertias(indices=np.array([0, 2, 4]), body_indices=np.array([10, 11]))
[[[4.2041304e-10  0.0  0.0  0.0  3.9026365e-10  0.0  0.0  0.0  1.3347495e-10]
  [4.2041304e-10  0.0  0.0  0.0  3.9026365e-10  0.0  0.0  0.0  1.3347495e-10]]
 ...
 [[4.2041304e-10  0.0  0.0  0.0  3.9026365e-10  0.0  0.0  0.0  1.3347495e-10]
  [4.2041304e-10  0.0  0.0  0.0  3.9026365e-10  0.0  0.0  0.0  1.3347495e-10]]]
get_body_inv_inertias(indices: Optional[Union[numpy.ndarray, List, torch.Tensor, warp.types.array]] = None, body_indices: Optional[Union[numpy.ndarray, List, torch.Tensor, warp.types.array]] = None, clone: bool = True) Union[numpy.ndarray, torch.Tensor, warp.types.indexedarray]

Get rigid body inverse inertias of articulations in the view

Parameters
  • indices (Optional[Union[np.ndarray, List, torch.Tensor, wp.array]], optional) – indices to specify which prims to query. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

  • body_indices (Optional[Union[np.ndarray, List, torch.Tensor, wp.array]], optional) – body indices to specify which bodies to query. Shape (K,). Where K <= num of bodies. Defaults to None (i.e: all bodies).

  • clone (bool, optional) – True to return a clone of the internal buffer. Otherwise False. Defaults to True.

Returns

rigid body inverse inertias of articulations in the view. Shape is (M, K, 9).

Return type

Union[np.ndarray, torch.Tensor, wp.indexedarray]

Example:

>>> # get all body inverse inertias. Returned shape is (5, 12, 9) for the example: 5 envs, 12 rigid bodies
>>> prims.get_body_inv_inertias()
[[[7.6990012e+05  0.0  0.0  0.0  6.0475844e+05  0.0  0.0  0.0  4.9185578e+05]
  [5.3514888e+05  0.0  0.0  0.0  6.9545931e+05  0.0  0.0  0.0  1.1027645e+06]
  ...
  [2.3786132e+09  0.0  0.0  0.0  2.5623703e+09  0.0  0.0  0.0  7.4920422e+09]
  [2.3786132e+09  0.0  0.0  0.0  2.5623703e+09  0.0  0.0  0.0  7.4920422e+09]]]
>>>
>>> # get finger body inverse inertias: panda_leftfinger (10) and panda_rightfinger (11)
>>> # for the first, middle and last of the 5 envs. Returned shape is (3, 2, 9)
>>> prims.get_body_inv_inertias(indices=np.array([0, 2, 4]), body_indices=np.array([10, 11]))
[[[2.3786132e+09  0.0  0.0  0.0  2.5623703e+09  0.0  0.0  0.0  7.4920422e+09]
  [2.3786132e+09  0.0  0.0  0.0  2.5623703e+09  0.0  0.0  0.0  7.4920422e+09]]
 ...
 [[2.3786132e+09  0.0  0.0  0.0  2.5623703e+09  0.0  0.0  0.0  7.4920422e+09]
  [2.3786132e+09  0.0  0.0  0.0  2.5623703e+09  0.0  0.0  0.0  7.4920422e+09]]]
get_body_inv_masses(indices: Optional[Union[numpy.ndarray, List, torch.Tensor, warp.types.array]] = None, body_indices: Optional[Union[numpy.ndarray, List, torch.Tensor, warp.types.array]] = None, clone: bool = True) Union[numpy.ndarray, torch.Tensor, warp.types.indexedarray]

Get rigid body inverse masses of articulations in the view

Parameters
  • indices (Optional[Union[np.ndarray, List, torch.Tensor, wp.array]], optional) – indices to specify which prims to query. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

  • body_indices (Optional[Union[np.ndarray, List, torch.Tensor, wp.array]], optional) – body indices to specify which bodies to query. Shape (K,). Where K <= num of bodies. Defaults to None (i.e: all bodies).

  • clone (bool, optional) – True to return a clone of the internal buffer. Otherwise False. Defaults to True.

Returns

rigid body inverse masses of articulations in the view. Shape is (M, K).

Return type

Union[np.ndarray, torch.Tensor, wp.indexedarray]

Example:

>>> # get all body inverse masses. Returned shape is (5, 12) for the example: 5 envs, 12 rigid bodies
>>> prims.get_body_inv_masses()
[[ 0.35534042  0.42372888  0.42025304  0.37737525  0.3710848  0.33542618  0.8860687
   2.4673615  10. 1.7910539  71.14793  71.14793]
 [ 0.35534042  0.42372888  0.42025304  0.37737525  0.3710848  0.33542618  0.8860687
   2.4673615  10. 1.7910539  71.14793  71.14793]
 [ 0.35534042  0.42372888  0.42025304  0.37737525  0.3710848  0.33542618  0.8860687
   2.4673615  10. 1.7910539  71.14793  71.14793]
 [ 0.35534042  0.42372888  0.42025304  0.37737525  0.3710848  0.33542618  0.8860687
   2.4673615  10. 1.7910539  71.14793  71.14793]
 [ 0.35534042  0.42372888  0.42025304  0.37737525  0.3710848  0.33542618  0.8860687
   2.4673615  10. 1.7910539  71.14793  71.14793]]
>>>
>>> # get finger body inverse masses: panda_leftfinger (10) and panda_rightfinger (11)
>>> # for the first, middle and last of the 5 envs. Returned shape is (3, 2)
>>> prims.get_body_inv_masses(indices=np.array([0, 2, 4]), body_indices=np.array([10, 11]))
[[71.14793 71.14793]
 [71.14793 71.14793]
 [71.14793 71.14793]]
get_body_masses(indices: Optional[Union[numpy.ndarray, List, torch.Tensor, warp.types.array]] = None, body_indices: Optional[Union[numpy.ndarray, List, torch.Tensor, warp.types.array]] = None, clone: bool = True) Union[numpy.ndarray, torch.Tensor, warp.types.indexedarray]

Get rigid body masses of articulations in the view

Parameters
  • indices (Optional[Union[np.ndarray, List, torch.Tensor, wp.array]], optional) – indices to specify which prims to query. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

  • body_indices (Optional[Union[np.ndarray, List, torch.Tensor, wp.array]], optional) – body indices to specify which bodies to query. Shape (K,). Where K <= num of bodies. Defaults to None (i.e: all bodies).

  • clone (bool, optional) – True to return a clone of the internal buffer. Otherwise False. Defaults to True.

Returns

rigid body masses of articulations in the view. Shape is (M, K).

Return type

Union[np.ndarray, torch.Tensor, wp.indexedarray]

Example:

>>> # get all body masses. Returned shape is (5, 12) for the example: 5 envs, 12 rigid bodies
>>> prims.get_body_masses()
[[2.8142028  2.3599997  2.3795187  2.6498823  2.6948018  2.981282
  1.1285807  0.40529126 0.1  0.5583305  0.01405522 0.01405522]
 [2.8142028  2.3599997  2.3795187  2.6498823  2.6948018  2.981282
  1.1285807  0.40529126 0.1  0.5583305  0.01405522 0.01405522]
 [2.8142028  2.3599997  2.3795187  2.6498823  2.6948018  2.981282
  1.1285807  0.40529126 0.1  0.5583305  0.01405522 0.01405522]
 [2.8142028  2.3599997  2.3795187  2.6498823  2.6948018  2.981282
  1.1285807  0.40529126 0.1  0.5583305  0.01405522 0.01405522]
 [2.8142028  2.3599997  2.3795187  2.6498823  2.6948018  2.981282
  1.1285807  0.40529126 0.1  0.5583305  0.01405522 0.01405522]]
>>>
>>> # get finger body masses: panda_leftfinger (10) and panda_rightfinger (11)
>>> # for the first, middle and last of the 5 envs. Returned shape is (3, 2)
>>> prims.get_body_masses(indices=np.array([0, 2, 4]), body_indices=np.array([10, 11]))
[[0.01405522 0.01405522]
 [0.01405522 0.01405522]
 [0.01405522 0.01405522]]
get_coriolis_and_centrifugal_forces(indices: Optional[Union[numpy.ndarray, List, torch.Tensor, warp.types.array]] = None, joint_indices: Optional[Union[numpy.ndarray, List, torch.Tensor, warp.types.array]] = None, clone: bool = True) Union[numpy.ndarray, torch.Tensor, warp.types.indexedarray]

Get the Coriolis and centrifugal forces (joint DOF forces required to counteract Coriolis and centrifugal forces for the given articulation state) of articulations in the view

Search for Coriolis and Centrifugal Forces in PhysX docs for more details

Parameters
  • indices (Optional[Union[np.ndarray, List, torch.Tensor, wp.array]], optional) – indices to specify which prims to query. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

  • joint_indices (Optional[Union[np.ndarray, List, torch.Tensor, wp.array]], optional) – joint indices to specify which joints to query. Shape (K,). Where K <= num of dofs. Defaults to None (i.e: all dofs).

  • clone (bool, optional) – True to return a clone of the internal buffer. Otherwise False. Defaults to True.

Returns

Coriolis and centrifugal forces of articulations in the view. Shape is (M, K).

Return type

Union[np.ndarray, torch.Tensor, wp.indexedarray]

Example:

>>> # get all coriolis and centrifugal forces. Returned shape is (5, 9) for the example: 5 envs, 9 DOFs
>>> prims.get_coriolis_and_centrifugal_forces()
[[ 1.6842524e-06 -1.8269569e-04  5.2162073e-07 -9.7677548e-05  3.0365106e-07
   6.7375149e-06  6.1105780e-08 -4.6237556e-06 -4.1627968e-06]
 [ 1.6842524e-06 -1.8269569e-04  5.2162073e-07 -9.7677548e-05  3.0365106e-07
   6.7375149e-06  6.1105780e-08 -4.6237556e-06 -4.1627968e-06]
 [ 1.6842561e-06 -1.8269687e-04  5.2162375e-07 -9.7677454e-05  3.0365084e-07
   6.7375931e-06  6.1106007e-08 -4.6237533e-06 -4.1627954e-06]
 [ 1.6842561e-06 -1.8269687e-04  5.2162375e-07 -9.7677454e-05  3.0365084e-07
   6.7375931e-06  6.1106007e-08 -4.6237533e-06 -4.1627954e-06]
 [ 1.6842524e-06 -1.8269569e-04  5.2162073e-07 -9.7677548e-05  3.0365106e-07
   6.7375149e-06  6.1105780e-08 -4.6237556e-06 -4.1627968e-06]]
>>>
>>> # get finger joint coriolis and centrifugal forces: panda_finger_joint1 (7) and panda_finger_joint2 (8)
>>> # for the first, middle and last of the 5 envs. Returned shape is (3, 2)
>>> prims.get_coriolis_and_centrifugal_forces(indices=np.array([0, 2, 4]), joint_indices=np.array([7, 8]))
[[-4.6237556e-06 -4.1627968e-06]
 [-4.6237533e-06 -4.1627954e-06]
 [-4.6237556e-06 -4.1627968e-06]]
get_default_state() omni.isaac.core.utils.types.XFormPrimViewState

Get the default states (positions and orientations) defined with the set_default_state method

Returns

returns the default state of the prims that is used after each reset.

Return type

XFormPrimViewState

Example:

>>> state = prims.get_default_state()
>>> state
<omni.isaac.core.utils.types.XFormPrimViewState object at 0x7f82f73e3070>
>>> state.positions
[[ 1.5  -0.75  0.  ]
 [ 1.5   0.75  0.  ]
 [ 0.   -0.75  0.  ]
 [ 0.    0.75  0.  ]
 [-1.5  -0.75  0.  ]]
>>> state.orientations
[[1. 0. 0. 0.]
 [1. 0. 0. 0.]
 [1. 0. 0. 0.]
 [1. 0. 0. 0.]
 [1. 0. 0. 0.]]
get_dof_index(dof_name: str) int

Get a DOF index in the joint buffers given its name

Parameters

dof_name (str) – name of the joint that corresponds to the degree of freedom to query

Returns

index of the degree of freedom in the joint buffers

Return type

int

Example:

>>> # get the index of the left finger joint: panda_finger_joint1
>>> prims.get_dof_index("panda_finger_joint1")
7
get_dof_limits() Union[numpy.ndarray, torch.Tensor]

Get the articulations DOFs limits (lower and upper)

Returns

degrees of freedom position limits. Shape is (N, num_dof, 2). For the last dimension, index 0 corresponds to lower limits and index 1 corresponds to upper limits

Return type

Union[np.ndarray, torch.Tensor, wp.array]

Example:

>>> # get DOF limits. Returned shape is (5, 9, 2) for the example: 5 envs, 9 DOFs
>>> prims.get_dof_limits()
[[[-2.8973  2.8973]
 [-1.7628  1.7628]
 [-2.8973  2.8973]
 [-3.0718 -0.0698]
 [-2.8973  2.8973]
 [-0.0175  3.7525]
 [-2.8973  2.8973]
 [ 0.      0.04  ]
 [ 0.      0.04  ]]
...
[[-2.8973  2.8973]
 [-1.7628  1.7628]
 [-2.8973  2.8973]
 [-3.0718 -0.0698]
 [-2.8973  2.8973]
 [-0.0175  3.7525]
 [-2.8973  2.8973]
 [ 0.      0.04  ]
 [ 0.      0.04  ]]]
get_dof_types(dof_names: Optional[List[str]] = None) List[str]

Get the DOF types given the DOF names

Parameters

dof_names (List[str], optional) – names of the joints that corresponds to the degrees of freedom to query. Defaults to None.

Returns

types of the joints that corresponds to the degrees of freedom. Types can be invalid, translation or rotation.

Return type

List[str]

Example:

>>> # get all DOF types
>>> prims.get_dof_types()
[<DofType.Rotation: 0>, <DofType.Rotation: 0>, <DofType.Rotation: 0>,
 <DofType.Rotation: 0>, <DofType.Rotation: 0>, <DofType.Rotation: 0>,
 <DofType.Rotation: 0>, <DofType.Translation: 1>, <DofType.Translation: 1>]
>>>
>>> # get only the finger DOF types: panda_finger_joint1 and panda_finger_joint2
>>> prims.get_dof_types(dof_names=["panda_finger_joint1", "panda_finger_joint2"])
[<DofType.Translation: 1>, <DofType.Translation: 1>]
get_effort_modes(indices: Optional[Union[numpy.ndarray, List, torch.Tensor, warp.types.array]] = None, joint_indices: Optional[Union[numpy.ndarray, List, torch.Tensor, warp.types.array]] = None) List[str]

Get effort modes for articulations in the view

Parameters
  • indices (Optional[Union[np.ndarray, List, torch.Tensor, wp.array]], optional) – indices to specify which prims to query. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

  • joint_indices (Optional[Union[np.ndarray, List, torch.Tensor, wp.array]], optional) – joint indices to specify which joints to query. Shape (K,). Where K <= num of dofs. Defaults to None (i.e: all dofs).

Returns

Returns a List of size (M, K) indicating the effort modes: acceleration or force

Return type

List

Example:

>>> # get the effort mode for all joints
>>> prims.get_effort_modes()
[['acceleration', 'acceleration', 'acceleration', 'acceleration', 'acceleration', 'acceleration', 'acceleration', 'acceleration', 'acceleration'],
 ['acceleration', 'acceleration', 'acceleration', 'acceleration', 'acceleration', 'acceleration', 'acceleration', 'acceleration', 'acceleration'],
 ['acceleration', 'acceleration', 'acceleration', 'acceleration', 'acceleration', 'acceleration', 'acceleration', 'acceleration', 'acceleration'],
 ['acceleration', 'acceleration', 'acceleration', 'acceleration', 'acceleration', 'acceleration', 'acceleration', 'acceleration', 'acceleration'],
 ['acceleration', 'acceleration', 'acceleration', 'acceleration', 'acceleration', 'acceleration', 'acceleration', 'acceleration', 'acceleration']]
>>>
>>> # get only the finger joints effort modes for the first, middle and last of the 5 envs
>>> prims.get_effort_modes(indices=np.array([0, 2, 4]), joint_indices=np.array([7, 8]))
[['acceleration', 'acceleration'], ['acceleration', 'acceleration'], ['acceleration', 'acceleration']]
get_enabled_self_collisions(indices: Optional[Union[numpy.ndarray, List, torch.Tensor, warp.types.array]] = None) Union[numpy.ndarray, torch.Tensor, warp.types.indexedarray]

Get the enable self collisions flag (physxArticulation:enabledSelfCollisions) for all articulations

Parameters

indices (Optional[Union[np.ndarray, List, torch.Tensor, wp.array]], optional) – indices to specify which prims to query. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

Returns

self collisions flags (boolean interpreted as int). shape (M,)

Return type

Union[np.ndarray, torch.Tensor, wp.indexedarray]

Example:

>>> # get all self collisions flags. Returned shape is (5,) for the example: 5 envs
>>> prims.get_enabled_self_collisions()
[0 0 0 0 0]
>>>
>>> # get the self collisions flags for the first, middle and last of the 5 envs. Returned shape is (3,)
>>> prims.get_enabled_self_collisions(indices=np.array([0, 2, 4]))
[0 0 0]
get_fixed_tendon_dampings(indices: Optional[Union[numpy.ndarray, List, torch.Tensor, warp.types.array]] = None, clone: bool = True) Union[numpy.ndarray, torch.Tensor, warp.types.indexedarray]

Get the dampings of fixed tendons for articulations in the view

Search for Fixed Tendon in PhysX docs for more details

Parameters
  • indices (Optional[Union[np.ndarray, List, torch.Tensor, wp.array]], optional) – indices to specify which prims to query. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

  • clone (bool, optional) – True to return a clone of the internal buffer. Otherwise False. Defaults to True.

Returns

fixed tendon dampings of articulations in the view. Shape is (M, K).

Return type

Union[np.ndarray, torch.Tensor, wp.indexedarray]

Example:

>>> # get the fixed tendon dampings
>>> # for the ShadowHand articulation that has 4 fixed tendons (prims.num_fixed_tendons)
>>> prims.get_fixed_tendon_dampings()
[[0. 0. 0. 0.]
 [0. 0. 0. 0.]
 [0. 0. 0. 0.]
 [0. 0. 0. 0.]
 [0. 0. 0. 0.]]
get_fixed_tendon_limit_stiffnesses(indices: Optional[Union[numpy.ndarray, List, torch.Tensor, warp.types.array]] = None, clone: bool = True) Union[numpy.ndarray, torch.Tensor, warp.types.indexedarray]

Get the limit stiffness of fixed tendons for articulations in the view

Search for Fixed Tendon in PhysX docs for more details

Parameters
  • indices (Optional[Union[np.ndarray, List, torch.Tensor, wp.array]], optional) – indices to specify which prims to query. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

  • clone (bool, optional) – True to return a clone of the internal buffer. Otherwise False. Defaults to True.

Returns

fixed tendon stiffnesses of articulations in the view. Shape is (M, K).

Return type

Union[np.ndarray, torch.Tensor, wp.indexedarray]

Example:

>>> # get the fixed tendon limit stiffnesses
>>> # for the ShadowHand articulation that has 4 fixed tendons (prims.num_fixed_tendons)
>>> prims.get_fixed_tendon_limit_stiffnesses()
[[0. 0. 0. 0.]
 [0. 0. 0. 0.]
 [0. 0. 0. 0.]
 [0. 0. 0. 0.]
 [0. 0. 0. 0.]]
get_fixed_tendon_limits(indices: Optional[Union[numpy.ndarray, List, torch.Tensor, warp.types.array]] = None, clone: bool = True) Union[numpy.ndarray, torch.Tensor, warp.types.indexedarray]

Get the limits of fixed tendons for articulations in the view

Search for Fixed Tendon in PhysX docs for more details

Parameters
  • indices (Optional[Union[np.ndarray, List, torch.Tensor, wp.array]], optional) – indices to specify which prims to query. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

  • clone (bool, optional) – True to return a clone of the internal buffer. Otherwise False. Defaults to True.

Returns

fixed tendon stiffnesses of articulations in the view. Shape is (M, K, 2).

Return type

Union[np.ndarray, torch.Tensor, wp.indexedarray]

Example:

>>> # get the fixed tendon limits
>>> # for the ShadowHand articulation that has 4 fixed tendons (prims.num_fixed_tendons)
>>> prims.get_fixed_tendon_limits()
[[[-0.001  0.001] [-0.001  0.001] [-0.001  0.001] [-0.001  0.001]]
 [[-0.001  0.001] [-0.001  0.001] [-0.001  0.001] [-0.001  0.001]]
 [[-0.001  0.001] [-0.001  0.001] [-0.001  0.001] [-0.001  0.001]]
 [[-0.001  0.001] [-0.001  0.001] [-0.001  0.001] [-0.001  0.001]]
 [[-0.001  0.001] [-0.001  0.001] [-0.001  0.001] [-0.001  0.001]]]
get_fixed_tendon_offsets(indices: Optional[Union[numpy.ndarray, List, torch.Tensor, warp.types.array]] = None, clone: bool = True) Union[numpy.ndarray, torch.Tensor, warp.types.indexedarray]

Get the offsets of fixed tendons for articulations in the view

Search for Fixed Tendon in PhysX docs for more details

Parameters
  • indices (Optional[Union[np.ndarray, List, torch.Tensor, wp.array]], optional) – indices to specify which prims to query. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

  • clone (bool, optional) – True to return a clone of the internal buffer. Otherwise False. Defaults to True.

Returns

fixed tendon stiffnesses of articulations in the view. Shape is (M, K).

Return type

Union[np.ndarray, torch.Tensor, wp.indexedarray]

Example:

>>> # get the fixed tendon offsets
>>> # for the ShadowHand articulation that has 4 fixed tendons (prims.num_fixed_tendons)
>>> prims.get_fixed_tendon_offsets()
[[0. 0. 0. 0.]
 [0. 0. 0. 0.]
 [0. 0. 0. 0.]
 [0. 0. 0. 0.]
 [0. 0. 0. 0.]]
get_fixed_tendon_rest_lengths(indices: Optional[Union[numpy.ndarray, List, torch.Tensor, warp.types.array]] = None, clone: bool = True) Union[numpy.ndarray, torch.Tensor, warp.types.indexedarray]

Get the rest length of fixed tendons for articulations in the view

Search for Fixed Tendon in PhysX docs for more details

Parameters
  • indices (Optional[Union[np.ndarray, List, torch.Tensor, wp.array]], optional) – indices to specify which prims to query. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

  • clone (bool, optional) – True to return a clone of the internal buffer. Otherwise False. Defaults to True.

Returns

fixed tendon stiffnesses of articulations in the view. Shape is (M, K).

Return type

Union[np.ndarray, torch.Tensor, wp.indexedarray]

Example:

>>> # get the fixed tendon rest lengths
>>> # for the ShadowHand articulation that has 4 fixed tendons (prims.num_fixed_tendons)
>>> prims.get_fixed_tendon_rest_lengths()
[[0. 0. 0. 0.]
 [0. 0. 0. 0.]
 [0. 0. 0. 0.]
 [0. 0. 0. 0.]
 [0. 0. 0. 0.]]
get_fixed_tendon_stiffnesses(indices: Optional[Union[numpy.ndarray, List, torch.Tensor, warp.types.array]] = None, clone: bool = True) Union[numpy.ndarray, torch.Tensor, warp.types.indexedarray]

Get the stiffness of fixed tendons for articulations in the view

Search for Fixed Tendon in PhysX docs for more details

Parameters
  • indices (Optional[Union[np.ndarray, List, torch.Tensor, wp.array]], optional) – indices to specify which prims to query. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

  • clone (bool, optional) – True to return a clone of the internal buffer. Otherwise False. Defaults to True.

Returns

fixed tendon stiffnesses of articulations in the view. Shape is (M, K).

Return type

Union[np.ndarray, torch.Tensor, wp.indexedarray]

Example:

>>> # get the fixed tendon stiffnesses
>>> # for the ShadowHand articulation that has 4 fixed tendons (prims.num_fixed_tendons)
>>> prims.get_fixed_tendon_stiffnesses()
[[0. 0. 0. 0.]
 [0. 0. 0. 0.]
 [0. 0. 0. 0.]
 [0. 0. 0. 0.]
 [0. 0. 0. 0.]]
get_friction_coefficients(indices: Optional[Union[numpy.ndarray, List, torch.Tensor, warp.types.array]] = None, joint_indices: Optional[Union[numpy.ndarray, List, torch.Tensor, warp.types.array]] = None, clone: bool = True) Union[numpy.ndarray, torch.Tensor, warp.types.array]

Get the friction coefficients for the articulation joints in the view

Search for “Joint Friction Coefficient” in PhysX docs for more details.

Parameters
  • indices (Optional[Union[np.ndarray, List, torch.Tensor, wp.array]], optional) – indices to specify which prims to query. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

  • joint_indices (Optional[Union[np.ndarray, List, torch.Tensor, wp.array]], optional) – joint indices to specify which joints to query. Shape (K,). Where K <= num of dofs. Defaults to None (i.e: all dofs).

  • clone (Optional[bool]) – True to return a clone of the internal buffer. Otherwise False. Defaults to True.

Returns

joint friction coefficients for articulations in the view. shape (M, K).

Return type

Union[np.ndarray, torch.Tensor, wp.indexedarray]

Example:

>>> # get joint friction coefficients. Returned shape is (5, 9) for the example: 5 envs, 9 DOFs
>>> prims.get_friction_coefficients()
[[0. 0. 0. 0. 0. 0. 0. 0. 0.]
 [0. 0. 0. 0. 0. 0. 0. 0. 0.]
 [0. 0. 0. 0. 0. 0. 0. 0. 0.]
 [0. 0. 0. 0. 0. 0. 0. 0. 0.]
 [0. 0. 0. 0. 0. 0. 0. 0. 0.]]
>>>
>>> # get only the finger joint (panda_finger_joint1 (7) and panda_finger_joint2 (8)) friction coefficients
>>> # for the first, middle and last of the 5 envs. Returned shape is (3, 2)
>>> prims.get_friction_coefficients(indices=np.array([0,2,4]), joint_indices=np.array([7,8]))
[[0. 0.]
 [0. 0.]
 [0. 0.]]
get_gains(indices: Optional[Union[numpy.ndarray, List, torch.Tensor, warp.types.array]] = None, joint_indices: Optional[Union[numpy.ndarray, List, torch.Tensor, warp.types.array]] = None, clone: bool = True) Tuple[typing.Union[numpy.ndarray, torch.Tensor], typing.Union[numpy.ndarray, torch.Tensor], typing.Union[warp.types.indexedarray, <Function index(a: vec2h, i: int32)>]]

Get the implicit Proportional-Derivative (PD) controller’s Kps (stiffnesses) and Kds (dampings) of articulations in the view

Parameters
  • indices (Optional[Union[np.ndarray, List, torch.Tensor, wp.array]], optional) – indices to specify which prims to query. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

  • joint_indices (Optional[Union[np.ndarray, List, torch.Tensor, wp.array]], optional) – joint indices to specify which joints to query. Shape (K,). Where K <= num of dofs. Defaults to None (i.e: all dofs).

  • clone (bool, optional) – True to return clones of the internal buffers. Otherwise False. Defaults to True.

Returns

stiffness and damping of articulations in the view respectively. shapes are (M, K).

Return type

Tuple[Union[np.ndarray, torch.Tensor], Union[np.ndarray, torch.Tensor], Union[wp.indexedarray, wp.index]]

Example:

>>> # get all joint stiffness and damping. Returned shape is (5, 9) for the example: 5 envs, 9 DOFs
>>> stiffnesses, dampings = prims.get_gains()
>>> stiffnesses
[[60000. 60000. 60000. 60000. 25000. 15000.  5000.  6000.  6000.]
 [60000. 60000. 60000. 60000. 25000. 15000.  5000.  6000.  6000.]
 [60000. 60000. 60000. 60000. 25000. 15000.  5000.  6000.  6000.]
 [60000. 60000. 60000. 60000. 25000. 15000.  5000.  6000.  6000.]
 [60000. 60000. 60000. 60000. 25000. 15000.  5000.  6000.  6000.]]
>>> dampings
[[3000. 3000. 3000. 3000. 3000. 3000. 3000. 1000. 1000.]
 [3000. 3000. 3000. 3000. 3000. 3000. 3000. 1000. 1000.]
 [3000. 3000. 3000. 3000. 3000. 3000. 3000. 1000. 1000.]
 [3000. 3000. 3000. 3000. 3000. 3000. 3000. 1000. 1000.]
 [3000. 3000. 3000. 3000. 3000. 3000. 3000. 1000. 1000.]]
>>>
>>> # get finger joints stiffness and damping: panda_finger_joint1 (7) and panda_finger_joint2 (8)
>>> # for the first, middle and last of the 5 envs. Returned shape is (3, 2)
>>> stiffnesses, dampings = prims.get_gains(indices=np.array([0, 2, 4]), joint_indices=np.array([7, 8]))
>>> stiffnesses
[[6000. 6000.]
 [6000. 6000.]
 [6000. 6000.]]
>>> dampings
[[1000. 1000.]
 [1000. 1000.]
 [1000. 1000.]]
get_generalized_gravity_forces(indices: Optional[Union[numpy.ndarray, List, torch.Tensor, warp.types.array]] = None, joint_indices: Optional[Union[numpy.ndarray, List, torch.Tensor, warp.types.array]] = None, clone: bool = True) Union[numpy.ndarray, torch.Tensor, warp.types.indexedarray]

Get the generalized gravity forces (joint DOF forces required to counteract gravitational forces for the given articulation pose) of articulations in the view

Search for Generalized Gravity Force in PhysX docs for more details

Parameters
  • indices (Optional[Union[np.ndarray, List, torch.Tensor, wp.array]], optional) – indices to specify which prims to query. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

  • joint_indices (Optional[Union[np.ndarray, List, torch.Tensor, wp.array]], optional) – joint indices to specify which joints to query. Shape (K,). Where K <= num of dofs. Defaults to None (i.e: all dofs).

  • clone (bool, optional) – True to return a clone of the internal buffer. Otherwise False. Defaults to True.

Returns

generalized gravity forces of articulations in the view. Shape is (M, K).

Return type

Union[np.ndarray, torch.Tensor, wp.indexedarray]

Example:

>>>

>>> # get all generalized gravity forces. Returned shape is (5, 9) for the example: 5 envs, 9 DOFs
>>> prims.get_generalized_gravity_forces()
[[ 1.32438602e-08 -6.90832138e+00 -1.08629465e-05  1.91585541e+01  5.13810664e-06
   1.18674076e+00  8.01788883e-06  5.18786255e-03 -5.18784765e-03]
 [ 1.32438602e-08 -6.90832138e+00 -1.08629465e-05  1.91585541e+01  5.13810664e-06
   1.18674076e+00  8.01788883e-06  5.18786255e-03 -5.18784765e-03]
 [ 1.32438585e-08 -6.90830994e+00 -1.08778477e-05  1.91585541e+01  5.14090061e-06
   1.18674052e+00  8.02161412e-06  5.18786255e-03 -5.18784765e-03]
 [ 1.32438585e-08 -6.90830994e+00 -1.08778477e-05  1.91585541e+01  5.14090061e-06
   1.18674052e+00  8.02161412e-06  5.18786255e-03 -5.18784765e-03]
 [ 1.32438602e-08 -6.90832138e+00 -1.08629465e-05  1.91585541e+01  5.13810664e-06
   1.18674076e+00  8.01788883e-06  5.18786255e-03 -5.18784765e-03]]
>>>
>>> # get finger joint generalized gravity forces: panda_finger_joint1 (7) and panda_finger_joint2 (8)
>>> # for the first, middle and last of the 5 envs. Returned shape is (3, 2)
>>> prims.get_generalized_gravity_forces(indices=np.array([0, 2, 4]), joint_indices=np.array([7, 8]))
[[ 0.00518786 -0.00518785]
 [ 0.00518786 -0.00518785]
 [ 0.00518786 -0.00518785]]
get_jacobian_shape() Union[numpy.ndarray, torch.Tensor, warp.types.array]

Get the Jacobian matrix shape of a single articulation

The Jacobian matrix maps the joint space velocities of a DOF to it’s cartesian and angular velocities

The shape of the Jacobian depends on the number of links (rigid bodies), DOFs, and whether the articulation base is fixed (e.g., robotic manipulators) or not (e.g,. mobile robots).

  • Fixed articulation base: (num_bodies - 1, 6, num_dof)

  • Non-fixed articulation base: (num_bodies, 6, num_dof + 6)

Each body has 6 values in the Jacobian representing its linear and angular motion along the three coordinate axes. The extra 6 DOFs in the last dimension, for non-fixed base cases, correspond to the linear and angular degrees of freedom of the free root link

Returns

shape of jacobian for a single articulation.

Return type

Union[np.ndarray, torch.Tensor, wp.array]

Example:

>>> # for the Franka Panda (a robotic manipulator with fixed base):
>>> # - num_bodies: 12
>>> # - num_dof: 9
>>> prims.get_jacobian_shape()
(11, 6, 9)
get_jacobians(indices: Optional[Union[numpy.ndarray, List, torch.Tensor, warp.types.array]] = None, clone: bool = True) Union[numpy.ndarray, torch.Tensor, warp.types.indexedarray]

Get the Jacobian matrices of articulations in the view

Note

The first dimension corresponds to the amount of wrapped articulations while the last 3 dimensions are the Jacobian matrix shape. Refer to the get_jacobian_shape method for details about the Jacobian matrix shape

Parameters
  • indices (Optional[Union[np.ndarray, List, torch.Tensor, wp.array]], optional) – indices to specify which prims to query. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

  • clone (bool, optional) – True to return a clone of the internal buffer. Otherwise False. Defaults to True.

Returns

Jacobian matrices of articulations in the view. Shape is (M, jacobian_shape).

Return type

Union[np.ndarray, torch.Tensor, wp.indexedarray]

Example:

>>> # get the Jacobian matrices. Returned shape is (5, 11, 6, 9) for the example: 5 envs, 12 links, 9 DOFs
>>> prims.get_jacobians()
[[[[ 4.2254178e-09  0.0000000e+00  0.0000000e+00 ...  0.0000000e+00  0.0000000e+00  0.0000000e+00]
   [ 1.2093576e-08  0.0000000e+00  0.0000000e+00 ...  0.0000000e+00  0.0000000e+00  0.0000000e+00]
   [-6.0873992e-16  0.0000000e+00  0.0000000e+00 ...  0.0000000e+00  0.0000000e+00  0.0000000e+00]
   [ 1.4458647e-07  0.0000000e+00  0.0000000e+00 ...  0.0000000e+00  0.0000000e+00  0.0000000e+00]
   [-1.8178657e-10  0.0000000e+00  0.0000000e+00 ...  0.0000000e+00  0.0000000e+00  0.0000000e+00]
   [ 9.9999976e-01  0.0000000e+00  0.0000000e+00 ...  0.0000000e+00  0.0000000e+00  0.0000000e+00]]
  ...
  [[-4.5089945e-02  8.1210062e-02 -3.8495898e-02 ...  2.8108317e-02  0.0000000e+00 -4.9317405e-02]
   [ 4.2863289e-01  9.7436900e-04  4.0475106e-01 ...  2.4577195e-03  0.0000000e+00  9.9807423e-01]
   [ 6.5973169e-09 -4.2914307e-01 -2.1542320e-02 ...  2.8352857e-02  0.0000000e+00 -3.7625343e-02]
   [ 1.4458647e-07 -1.1999309e-02 -5.3927803e-01 ...  7.0976764e-01  0.0000000e+00  0.0000000e+00]
   [-1.8178657e-10  9.9992776e-01 -6.4710006e-03 ...  8.5178167e-03  0.0000000e+00  0.0000000e+00]
   [ 9.9999976e-01 -3.8743019e-07  8.4210289e-01 ... -7.0438433e-01  0.0000000e+00  0.0000000e+00]]]]
get_joint_index(joint_name: str) int

Get a joint index in the joint buffers given its name

Parameters

joint_name (str) – name of the joint that corresponds to the index of the joint in the articulation

Returns

index of the joint in the joint buffers

Return type

int

get_joint_positions(indices: Optional[Union[numpy.ndarray, List, torch.Tensor, warp.types.array]] = None, joint_indices: Optional[Union[numpy.ndarray, List, torch.Tensor, warp.types.array]] = None, clone: bool = True) Union[numpy.ndarray, torch.Tensor, warp.types.indexedarray]

Get the joint positions of articulations in the view

Parameters
  • indices (Optional[Union[np.ndarray, List, torch.Tensor, wp.array]], optional) – indices to specify which prims to query. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

  • joint_indices (Optional[Union[np.ndarray, List, torch.Tensor, wp.array]], optional) – joint indices to specify which joints to query. Shape (K,). Where K <= num of dofs. Defaults to None (i.e: all dofs).

  • clone (bool, optional) – True to return a clone of the internal buffer. Otherwise False. Defaults to True.

Returns

joint positions of articulations in the view. Shape is (M, K).

Return type

Union[np.ndarray, torch.Tensor, wp.indexedarray]

Example:

>>> # get all joint positions. Returned shape is (5, 9) for the example: 5 envs, 9 DOFs
>>> prims.get_joint_positions()
[[ 1.1999921e-02 -5.6962633e-01  1.3219320e-08 -2.8105433e+00  6.8276213e-06
   3.0301569e+00  7.3234755e-01  3.9912373e-02  3.9999999e-02]
 [ 1.1999921e-02 -5.6962633e-01  1.3219320e-08 -2.8105433e+00  6.8276213e-06
   3.0301569e+00  7.3234755e-01  3.9912373e-02  3.9999999e-02]
 [ 1.1999921e-02 -5.6962633e-01  1.3220056e-08 -2.8105433e+00  6.8276104e-06
   3.0301569e+00  7.3234755e-01  3.9912373e-02  3.9999999e-02]
 [ 1.1999921e-02 -5.6962633e-01  1.3220056e-08 -2.8105433e+00  6.8276104e-06
   3.0301569e+00  7.3234755e-01  3.9912373e-02  3.9999999e-02]
 [ 1.1999921e-02 -5.6962633e-01  1.3219320e-08 -2.8105433e+00  6.8276213e-06
   3.0301569e+00  7.3234755e-01  3.9912373e-02  3.9999999e-02]]
>>>
>>> # get finger joint positions: panda_finger_joint1 (7) and panda_finger_joint2 (8)
>>> # for the first, middle and last of the 5 envs. Returned shape is (3, 2)
>>> prims.get_joint_positions(indices=np.array([0, 2, 4]), joint_indices=np.array([7, 8]))
[[0.03991237 0.04      ]
 [0.03991237 0.04      ]
 [0.03991237 0.04      ]]
get_joint_velocities(indices: Optional[Union[numpy.ndarray, List, torch.Tensor, warp.types.array]] = None, joint_indices: Optional[Union[numpy.ndarray, List, torch.Tensor, warp.types.array]] = None, clone: bool = True) Union[numpy.ndarray, torch.Tensor, warp.types.indexedarray]

Get the joint velocities of articulations in the view

Parameters
  • indices (Optional[Union[np.ndarray, List, torch.Tensor, wp.array]], optional) – indices to specify which prims to query. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

  • joint_indices (Optional[Union[np.ndarray, List, torch.Tensor, wp.array]], optional) – joint indices to specify which joints to query. Shape (K,). Where K <= num of dofs. Defaults to None (i.e: all dofs).

  • clone (bool, optional) – True to return a clone of the internal buffer. Otherwise False. Defaults to True.

Returns

joint velocities of articulations in the view. Shape is (M, K).

Return type

Union[np.ndarray, torch.Tensor, wp.indexedarray]

Example:

>>> # get all joint velocities. Returned shape is (5, 9) for the example: 5 envs, 9 DOFs
>>> prims.get_joint_velocities()
[[ 1.9010375e-06 -7.6763844e-03 -2.1396865e-07  1.1063669e-02 -4.6333633e-05
   3.4824573e-02  8.8469200e-02  5.4033857e-04  1.0287426e-05]
 [ 1.9010375e-06 -7.6763844e-03 -2.1396865e-07  1.1063669e-02 -4.6333633e-05
   3.4824573e-02  8.8469200e-02  5.4033857e-04  1.0287426e-05]
 [ 1.9010074e-06 -7.6763779e-03 -2.1403629e-07  1.1063648e-02 -4.6333400e-05
   3.4824558e-02  8.8469170e-02  5.4033566e-04  1.0287110e-05]
 [ 1.9010074e-06 -7.6763779e-03 -2.1403629e-07  1.1063648e-02 -4.6333400e-05
   3.4824558e-02  8.8469170e-02  5.4033566e-04  1.0287110e-05]
 [ 1.9010375e-06 -7.6763844e-03 -2.1396865e-07  1.1063669e-02 -4.6333633e-05
   3.4824573e-02  8.8469200e-02  5.4033857e-04  1.0287426e-05]]
>>>
>>> # get finger joint velocities: panda_finger_joint1 (7) and panda_finger_joint2 (8)
>>> # for the first, middle and last of the 5 envs. Returned shape is (3, 2)
>>> prims.get_joint_velocities(indices=np.array([0, 2, 4]), joint_indices=np.array([7, 8]))
[[5.4033857e-04 1.0287426e-05]
 [5.4033566e-04 1.0287110e-05]
 [5.4033857e-04 1.0287426e-05]]
get_joints_default_state() omni.isaac.core.utils.types.JointsState

Get the default joint states defined with the set_joints_default_state method

Returns

an object that contains the default joint states

Return type

JointsState

Example:

>>> # returned shape is (5, 9) for the example: 5 envs, 9 DOFs
>>> states = prims.get_joints_default_state()
>>> states
<omni.isaac.core.utils.types.JointsState object at 0x7fc2c174fd90>
>>> states.positions
[[ 0.   -1.    0.   -2.2   0.    2.4   0.8   0.04  0.04]
 [ 0.   -1.    0.   -2.2   0.    2.4   0.8   0.04  0.04]
 [ 0.   -1.    0.   -2.2   0.    2.4   0.8   0.04  0.04]
 [ 0.   -1.    0.   -2.2   0.    2.4   0.8   0.04  0.04]
 [ 0.   -1.    0.   -2.2   0.    2.4   0.8   0.04  0.04]]
>>> states.velocities
[[0. 0. 0. 0. 0. 0. 0. 0. 0.]
 [0. 0. 0. 0. 0. 0. 0. 0. 0.]
 [0. 0. 0. 0. 0. 0. 0. 0. 0.]
 [0. 0. 0. 0. 0. 0. 0. 0. 0.]
 [0. 0. 0. 0. 0. 0. 0. 0. 0.]]
>>> states.efforts
[[0. 0. 0. 0. 0. 0. 0. 0. 0.]
 [0. 0. 0. 0. 0. 0. 0. 0. 0.]
 [0. 0. 0. 0. 0. 0. 0. 0. 0.]
 [0. 0. 0. 0. 0. 0. 0. 0. 0.]
 [0. 0. 0. 0. 0. 0. 0. 0. 0.]]
get_joints_state() omni.isaac.core.utils.types.JointsState

Get the current joint states (positions and velocities)

Returns

an object that contains the current joint positions and velocities

Return type

JointsState

Example:

>>> # returned shape is (5, 9) for the example: 5 envs, 9 DOFs
>>> states = prims.get_joints_state()
>>> states
<omni.isaac.core.utils.types.JointsState object at 0x7fc1a23a82e0>
>>> states.positions
[[ 1.1999921e-02 -5.6962633e-01  1.3219320e-08 -2.8105433e+00  6.8276213e-06
   3.0301569e+00  7.3234755e-01  3.9912373e-02  3.9999999e-02]
 [ 1.1999921e-02 -5.6962633e-01  1.3219320e-08 -2.8105433e+00  6.8276213e-06
   3.0301569e+00  7.3234755e-01  3.9912373e-02  3.9999999e-02]
 [ 1.1999921e-02 -5.6962633e-01  1.3220056e-08 -2.8105433e+00  6.8276104e-06
   3.0301569e+00  7.3234755e-01  3.9912373e-02  3.9999999e-02]
 [ 1.1999921e-02 -5.6962633e-01  1.3220056e-08 -2.8105433e+00  6.8276104e-06
   3.0301569e+00  7.3234755e-01  3.9912373e-02  3.9999999e-02]
 [ 1.1999921e-02 -5.6962633e-01  1.3219320e-08 -2.8105433e+00  6.8276213e-06
   3.0301569e+00  7.3234755e-01  3.9912373e-02  3.9999999e-02]]
>>> states.velocities
[[ 1.9010375e-06 -7.6763844e-03 -2.1396865e-07  1.1063669e-02 -4.6333633e-05
   3.4824573e-02  8.8469200e-02  5.4033857e-04  1.0287426e-05]
 [ 1.9010375e-06 -7.6763844e-03 -2.1396865e-07  1.1063669e-02 -4.6333633e-05
   3.4824573e-02  8.8469200e-02  5.4033857e-04  1.0287426e-05]
 [ 1.9010074e-06 -7.6763779e-03 -2.1403629e-07  1.1063648e-02 -4.6333400e-05
   3.4824558e-02  8.8469170e-02  5.4033566e-04  1.0287110e-05]
 [ 1.9010074e-06 -7.6763779e-03 -2.1403629e-07  1.1063648e-02 -4.6333400e-05
   3.4824558e-02  8.8469170e-02  5.4033566e-04  1.0287110e-05]
 [ 1.9010375e-06 -7.6763844e-03 -2.1396865e-07  1.1063669e-02 -4.6333633e-05
   3.4824573e-02  8.8469200e-02  5.4033857e-04  1.0287426e-05]]
get_linear_velocities(indices: Optional[Union[numpy.ndarray, list, torch.Tensor, warp.types.array]] = None, clone=True) Union[numpy.ndarray, torch.Tensor, warp.types.indexedarray]

Get the linear velocities of prims in the view.

Parameters
  • indices (Optional[Union[np.ndarray, list, torch.Tensor, wp.array]], optional) – indices to specify which prims to query. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view)

  • clone (bool, optional) – True to return a clone of the internal buffer. Otherwise False. Defaults to True.

Returns

linear velocities of the prims in the view. shape is (M, 3).

Return type

Union[np.ndarray, torch.Tensor, wp.indexedarray]

Example:

>>> # get all articulation linear velocities. Returned shape is (5, 3) for the example: 5 envs, linear (3)
>>> prims.get_linear_velocities()
[[0. 0. 0.]
 [0. 0. 0.]
 [0. 0. 0.]
 [0. 0. 0.]
 [0. 0. 0.]]
>>>
>>> # get only the articulation linear velocities for the first, middle and last of the 5 envs.
>>> # Returned shape is (3, 3) for the example: 3 envs selected, linear (3)
>>> prims.get_linear_velocities(indices=np.array([0, 2, 4]))
[[0. 0. 0.]
 [0. 0. 0.]
 [0. 0. 0.]]

Get a link index in the link buffers given its name

Parameters

link_name (str) – name of the link that corresponds to the index of the link in the articulation

Returns

index of the link in the link buffers

Return type

int

get_local_poses(indices: Optional[Union[numpy.ndarray, list, torch.Tensor, warp.types.array]] = None) Union[Tuple[numpy.ndarray, numpy.ndarray], Tuple[torch.Tensor, torch.Tensor], Tuple[warp.types.indexedarray, warp.types.indexedarray]]

Get prim poses in the view with respect to the local frame (the prim’s parent frame).

Parameters

indices (Optional[Union[np.ndarray, list, torch.Tensor, wp.array]], optional) – indices to specify which prims to query. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view)

Returns

first index is positions in the local frame of the prims. shape is (M, 3). Second index is quaternion orientations in the local frame of the prims. Quaternion is scalar-first (w, x, y, z). shape is (M, 4).

Return type

Union[Tuple[np.ndarray, np.ndarray], Tuple[torch.Tensor, torch.Tensor], Tuple[wp.indexedarray, wp.indexedarray]]

Example:

>>> # get all articulation poses with respect to the local frame.
>>> # Returned shape is position (5, 3) and orientation (5, 4) for the example: 5 envs
>>> positions, orientations = prims.get_local_poses()
>>> positions
[[ 0.0000000e+00  0.0000000e+00 -2.8610229e-08]
 [ 0.0000000e+00  0.0000000e+00 -2.8610229e-08]
 [-4.5299529e-08  0.0000000e+00 -2.8610229e-08]
 [-4.5299529e-08  0.0000000e+00 -2.8610229e-08]
 [ 0.0000000e+00  0.0000000e+00 -2.8610229e-08]]
>>> orientations
[[1. 0. 0. 0.]
 [1. 0. 0. 0.]
 [1. 0. 0. 0.]
 [1. 0. 0. 0.]
 [1. 0. 0. 0.]]
>>>
>>> # get only the articulation poses with respect to the local frame for the first, middle and last of the 5 envs.
>>> # Returned shape is position (3, 3) and orientation (3, 4) for the example: 3 envs selected
>>> positions, orientations = prims.get_local_poses(indices=np.array([0, 2, 4]))
>>> positions
[[ 0.0000000e+00  0.0000000e+00 -2.8610229e-08]
 [-4.5299529e-08  0.0000000e+00 -2.8610229e-08]
 [ 0.0000000e+00  0.0000000e+00 -2.8610229e-08]]
>>> orientations
[[1. 0. 0. 0.]
 [1. 0. 0. 0.]
 [1. 0. 0. 0.]]
get_local_scales(indices: Optional[Union[numpy.ndarray, list, torch.Tensor, warp.types.array]] = None) Union[numpy.ndarray, torch.Tensor, warp.types.indexedarray]

Get prim scales in the view with respect to the local frame (the parent’s frame).

Parameters

indices (Optional[Union[np.ndarray, list, torch.Tensor, wp.array]], optional) – indices to specify which prims to query. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

Returns

scales applied to the prim’s dimensions in the local frame. shape is (M, 3).

Return type

Union[np.ndarray, torch.Tensor, wp.indexedarray]

Example:

>>> # get all prims scales with respect to the local frame.
>>> # Returned shape is (5, 3) for the example: 5 envs
>>> prims.get_local_scales()
[[1. 1. 1.]
 [1. 1. 1.]
 [1. 1. 1.]
 [1. 1. 1.]
 [1. 1. 1.]]
>>>
>>> # get only the prims scales with respect to the local frame for the first, middle and last of the 5 envs.
>>> # Returned shape is (3, 3) for the example: 3 envs selected
>>> prims.get_local_scales(indices=np.array([0, 2, 4]))
[[1. 1. 1.]
 [1. 1. 1.]
 [1. 1. 1.]]
get_mass_matrices(indices: Optional[Union[numpy.ndarray, List, torch.Tensor, warp.types.array]] = None, clone: bool = True) Union[numpy.ndarray, torch.Tensor, warp.types.indexedarray]

Get the mass matrices of articulations in the view

Note

The first dimension corresponds to the amount of wrapped articulations while the last 2 dimensions are the mass matrix shape. Refer to the get_mass_matrix_shape method for details about the mass matrix shape

Parameters
  • indices (Optional[Union[np.ndarray, List, torch.Tensor, wp.array]], optional) – indices to specify which prims to query. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

  • clone (bool, optional) – True to return a clone of the internal buffer. Otherwise False. Defaults to True.

Returns

mass matrices of articulations in the view. Shape is (M, mass_matrix_shape).

Return type

Union[np.ndarray, torch.Tensor, wp.indexedarray]

Example:

>>> # get the mass matrices. Returned shape is (5, 9, 9) for the example: 5 envs, 9 DOFs
>>> prims.get_mass_matrices()
[[[ 5.0900602e-01  1.1794259e-06  4.2570841e-01 -1.6387942e-06 -3.1573933e-02
   -1.9736715e-06 -3.1358242e-04 -6.0441834e-03  6.0441834e-03]
  [ 1.1794259e-06  1.0598221e+00  7.4729815e-07 -4.2621672e-01  2.3612277e-08
   -4.9647894e-02 -2.9080724e-07 -1.8432185e-04  1.8432130e-04]
  ...
  [-6.0441834e-03 -1.8432185e-04 -5.7159867e-03  4.0070520e-04  9.6930371e-04
    1.2324301e-04  2.5264668e-10  1.4055224e-02  0.0000000e+00]
  [ 6.0441834e-03  1.8432130e-04  5.7159867e-03 -4.0070404e-04 -9.6930366e-04
   -1.2324269e-04 -3.6906206e-10  0.0000000e+00  1.4055224e-02]]]
get_mass_matrix_shape() Union[numpy.ndarray, torch.Tensor, warp.types.array]

Get the mass matrix shape of a single articulation

The mass matrix contains the generalized mass of the robot depending on the current configuration

The shape of the max matrix depends on the number of DOFs: (num_dof, num_dof)

Returns

shape of mass matrix for a single articulation.

Return type

Union[np.ndarray, torch.Tensor, wp.array]

Example:

>>> # for the Franka Panda:
>>> # - num_dof: 9
>>> prims.get_jacobian_shape()
(9, 9)
get_max_efforts(indices: Optional[Union[numpy.ndarray, List, torch.Tensor, warp.types.array]] = None, joint_indices: Optional[Union[numpy.ndarray, List, torch.Tensor, warp.types.array]] = None, clone: bool = True) Union[numpy.ndarray, torch.Tensor, warp.types.indexedarray]

Get the maximum efforts for articulation in the view

Parameters
  • indices (Optional[Union[np.ndarray, List, torch.Tensor, wp.array]], optional) – indices to specify which prims to query. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

  • joint_indices (Optional[Union[np.ndarray, List, torch.Tensor, wp.array]], optional) – joint indices to specify which joints to query. Shape (K,). Where K <= num of dofs. Defaults to None (i.e: all dofs).

  • clone (Optional[bool]) – True to return a clone of the internal buffer. Otherwise False. Defaults to True.

Returns

maximum efforts for articulations in the view. shape (M, K).

Return type

Union[np.ndarray, torch.Tensor, wp.indexedarray]

Example:

>>> # get all joint maximum efforts. Returned shape is (5, 9) for the example: 5 envs, 9 DOFs
>>> prims.get_max_efforts()
[[5220. 5220. 5220. 5220.  720.  720.  720.  720.  720.]
 [5220. 5220. 5220. 5220.  720.  720.  720.  720.  720.]
 [5220. 5220. 5220. 5220.  720.  720.  720.  720.  720.]
 [5220. 5220. 5220. 5220.  720.  720.  720.  720.  720.]
 [5220. 5220. 5220. 5220.  720.  720.  720.  720.  720.]]
>>>
>>> # get finger joint maximum efforts: panda_finger_joint1 (7) and panda_finger_joint2 (8)
>>> # for the first, middle and last of the 5 envs. Returned shape is (3, 2)
>>> prims.get_max_efforts(indices=np.array([0, 2, 4]), joint_indices=np.array([7, 8]))
[[720. 720.]
 [720. 720.]
 [720. 720.]]
get_measured_joint_efforts(indices: Optional[Union[numpy.ndarray, List, torch.Tensor, warp.types.array]] = None, joint_indices: Optional[Union[numpy.ndarray, List, torch.Tensor, warp.types.array]] = None, clone: bool = True) Union[numpy.ndarray, torch.Tensor, warp.types.indexedarray]

Returns the efforts computed/measured by the physics solver of the joint forces in the DOF motion direction

Parameters
  • indices (Optional[Union[np.ndarray, List, torch.Tensor]], optional) – indices to specify which prims to query. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

  • joint_indices (Optional[Union[np.ndarray, List, torch.Tensor]], optional) – joint indices to specify which joints to query. Shape (K,). Where K <= num of dofs. Defaults to None (i.e: all dofs).

  • clone (bool, optional) – True to return a clone of the internal buffer. Otherwise False. Defaults to True.

Returns

computed joint efforts of articulations in the view. shape is (M, K).

Return type

Union[np.ndarray, torch.Tensor]

Example:

>>> # get all measured joint efforts. Returned shape is (5, 9) for the example: 5 envs, 9 DOFs
>>> prims.get_measured_joint_efforts()
[[ 4.8250298e-05 -6.9073005e+00  5.3364405e-05  1.9157070e+01 -5.8759182e-05
   1.1863427e+00 -5.6388220e-05  5.1680300e-03 -5.1910817e-03]
 [ 4.8250298e-05 -6.9073005e+00  5.3364405e-05  1.9157070e+01 -5.8759182e-05
   1.1863427e+00 -5.6388220e-05  5.1680300e-03 -5.1910817e-03]
 [ 4.8254540e-05 -6.9072919e+00  5.3344327e-05  1.9157072e+01 -5.8761045e-05
   1.1863427e+00 -5.6405144e-05  5.1680212e-03 -5.1910840e-03]
 [ 4.8254540e-05 -6.9072919e+00  5.3344327e-05  1.9157072e+01 -5.8761045e-05
   1.1863427e+00 -5.6405144e-05  5.1680212e-03 -5.1910840e-03]
 [ 4.8250298e-05 -6.9073005e+00  5.3364405e-05  1.9157070e+01 -5.8759182e-05
   1.1863427e+00 -5.6388220e-05  5.1680300e-03  -5.1910817e-03]]
>>>
>>> # get finger measured joint efforts: panda_finger_joint1 (7) and panda_finger_joint2 (8)
>>> # for the first, middle and last of the 5 envs. Returned shape is (3, 2)
>>> prims.get_measured_joint_efforts(indices=np.array([0, 2, 4]), joint_indices=np.array([7, 8]))
[[ 0.00516803 -0.00519108]
 [ 0.00516802 -0.00519108]
 [ 0.00516803 -0.00519108]]
get_measured_joint_forces(indices: Optional[Union[numpy.ndarray, List, torch.Tensor]] = None, joint_indices: Optional[Union[numpy.ndarray, List, torch.Tensor]] = None, clone: bool = True) Union[numpy.ndarray, torch.Tensor]

Get the measured joint reaction forces and torques (link incoming joint forces and torques) to external loads

Note

Since the name->index map for joints has not been exposed yet, it is possible to access the joint names and their indices through the articulation metadata.

prims._metadata.joint_names  # list of names
prims._metadata.joint_indices  # dict of name: index

To retrieve a specific row for the link incoming joint force/torque use joint_index + 1

Parameters
  • indices (Optional[Union[np.ndarray, List, torch.Tensor]], optional) – indices to specify which prims to query. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

  • joint_indices (Optional[Union[np.ndarray, List, torch.Tensor]], optional) – link indices to specify which link’s incoming joints to query. Shape (K,). Where K <= num of links/bodies. Defaults to None (i.e: all dofs).

  • clone (bool, optional) – True to return a clone of the internal buffer. Otherwise False. Defaults to True.

Returns

joint forces and torques of articulations in the view. Shape is (M, num_joint + 1, 6). Column index 0 is the incoming joint of the base link. For the last dimension the first 3 values are for forces and the last 3 for torques

Return type

Union[np.ndarray, torch.Tensor]

Example:

>>> # get all measured joint forces and torques. Returned shape is (5, 12, 6) for the example:
>>> # 5 envs, 9 DOFs (but 12 joints including the fixed and root joints)
>>> prims.get_measured_joint_forces()
[[[ 0.00000000e+00  0.00000000e+00  0.00000000e+00  0.00000000e+00  0.00000000e+00  0.00000000e+00]
  [ 1.49950760e+02  3.52353277e-06  5.62586996e-04  4.82502983e-05 -6.90729856e+00  2.69259126e-05]
  [-2.60467059e-05 -1.06778236e+02 -6.83844986e+01 -6.90730047e+00 -5.27759657e-05 -1.24897576e-06]
  [ 8.71209946e+01 -4.46646191e-05 -5.57951622e+01  5.33644052e-05 -2.45385647e+01  1.38957939e-05]
  [ 5.18576926e-05 -4.81099091e+01  6.07092705e+01  1.91570702e+01 -5.81023924e-05  1.46875891e-06]
  [-3.16910419e+01  2.31799815e-04  3.99901695e+01 -5.87591821e-05 -1.18634319e+00  2.24427877e-05]
  [-1.07621672e-04  1.53405371e+01 -1.54584875e+01  1.18634272e+00  6.09036942e-05 -1.60679410e-05]
  [-7.54189777e+00 -5.08146524e+00 -5.65130091e+00 -5.63882204e-05  3.88599992e-01 -3.49432468e-01]
  [ 4.74214745e+00 -3.19458222e+00  3.55281782e+00  5.58562024e-05  8.47946014e-03  7.64050474e-03]
  [ 4.07607269e+00  2.16406956e-01 -4.05131817e+00 -5.95658377e-04  1.14070829e-02  2.13965313e-06]
  [ 5.16803004e-03 -9.77545828e-02 -9.70939621e-02 -8.41282599e-12 -1.29066744e-12 -1.93477560e-11]
  [-5.19108167e-03  9.75882635e-02 -9.71064270e-02  8.41282859e-12  1.29066018e-12 -1.93477543e-11]]
 ...
 [[ 0.00000000e+00  0.00000000e+00  0.00000000e+00  0.00000000e+00  0.00000000e+00  0.00000000e+00]
  [ 1.49950760e+02  3.52353277e-06  5.62586996e-04  4.82502983e-05 -6.90729856e+00  2.69259126e-05]
  [-2.60467059e-05 -1.06778236e+02 -6.83844986e+01 -6.90730047e+00 -5.27759657e-05 -1.24897576e-06]
  [ 8.71209946e+01 -4.46646191e-05 -5.57951622e+01  5.33644052e-05 -2.45385647e+01  1.38957939e-05]
  [ 5.18576926e-05 -4.81099091e+01  6.07092705e+01  1.91570702e+01 -5.81023924e-05  1.46875891e-06]
  [-3.16910419e+01  2.31799815e-04  3.99901695e+01 -5.87591821e-05 -1.18634319e+00  2.24427877e-05]
  [-1.07621672e-04  1.53405371e+01 -1.54584875e+01  1.18634272e+00  6.09036942e-05 -1.60679410e-05]
  [-7.54189777e+00 -5.08146524e+00 -5.65130091e+00 -5.63882204e-05  3.88599992e-01 -3.49432468e-01]
  [ 4.74214745e+00 -3.19458222e+00  3.55281782e+00  5.58562024e-05  8.47946014e-03  7.64050474e-03]
  [ 4.07607269e+00  2.16406956e-01 -4.05131817e+00 -5.95658377e-04  1.14070829e-02  2.13965313e-06]
  [ 5.16803004e-03 -9.77545828e-02 -9.70939621e-02 -8.41282599e-12 -1.29066744e-12 -1.93477560e-11]
  [-5.19108167e-03  9.75882635e-02 -9.71064270e-02  8.41282859e-12  1.29066018e-12 -1.93477543e-11]]]
>>>
>>> # get measured joint forces and torques for the fingers for the first, middle and last of the 5 envs.
>>> # Returned shape is (3, 2, 6)
>>> metadata = prims._metadata
>>> joint_indices = 1 + np.array([
>>>     metadata.joint_indices["panda_finger_joint1"],
>>>     metadata.joint_indices["panda_finger_joint2"],
>>> ])
>>> joint_indices
[10 11]
>>> prims.get_measured_joint_forces(indices=np.array([0, 2, 4]), joint_indices=joint_indices)
[[[ 5.1680300e-03 -9.7754583e-02 -9.7093962e-02 -8.4128260e-12 -1.2906674e-12 -1.9347756e-11]
  [-5.1910817e-03  9.7588263e-02 -9.7106427e-02  8.4128286e-12  1.2906602e-12 -1.9347754e-11]]
 [[ 5.1680212e-03 -9.7754560e-02 -9.7093947e-02 -8.4141834e-12 -1.2907383e-12 -1.9348209e-11]
  [-5.1910840e-03  9.7588278e-02 -9.7106412e-02  8.4141869e-12  1.2907335e-12 -1.9348207e-11]]
 [[ 5.1680300e-03 -9.7754583e-02 -9.7093962e-02 -8.4128260e-12 -1.2906674e-12 -1.9347756e-11]
  [-5.1910817e-03  9.7588263e-02 -9.7106427e-02  8.4128286e-12  1.2906602e-12 -1.9347754e-11]]]
get_sleep_thresholds(indices: Optional[Union[numpy.ndarray, List, torch.Tensor, warp.types.array]] = None) Union[numpy.ndarray, torch.Tensor, warp.types.indexedarray]

Get the threshold for articulations to enter a sleep state

Search for Articulations and Sleeping in PhysX docs for more details

Parameters

indices (Optional[Union[np.ndarray, List, torch.Tensor, wp.array]], optional) – indices to specify which prims to query. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

Returns

sleep thresholds. shape (M,).

Return type

Union[np.ndarray, torch.Tensor, wp.indexedarray]

Example:

>>> # get all sleep thresholds. Returned shape is (5,) for the example: 5 envs
>>> prims.get_sleep_thresholds()
[0.005 0.005 0.005 0.005 0.005]
>>>
>>> # get the sleep thresholds for the first, middle and last of the 5 envs. Returned shape is (3,)
>>> prims.get_sleep_thresholds(indices=np.array([0, 2, 4]))
[0.005 0.005 0.005]
get_solver_position_iteration_counts(indices: Optional[Union[numpy.ndarray, List, torch.Tensor, warp.types.array]] = None) Union[numpy.ndarray, torch.Tensor, warp.types.indexedarray]

Get the solver (position) iteration count for the articulations

The solver iteration count determines how accurately contacts, drives, and limits are resolved. Search for Solver Iteration Count in PhysX docs for more details.

Parameters

indices (Optional[Union[np.ndarray, List, torch.Tensor, wp.array]], optional) – indices to specify which prims to query. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

Returns

position iteration count. Shape (M,).

Return type

Union[np.ndarray, torch.Tensor, wp.indexedarray]

Example:

>>> # get all position iteration count. Returned shape is (5,) for the example: 5 envs
>>> prims.get_solver_position_iteration_counts()
[32 32 32 32 32]
>>>
>>> # get the position iteration count for the first, middle and last of the 5 envs. Returned shape is (3,)
>>> prims.get_solver_position_iteration_counts(indices=np.array([0, 2, 4]))
[32 32 32]
get_solver_velocity_iteration_counts(indices: Optional[Union[numpy.ndarray, List, torch.Tensor, warp.types.array]] = None) Union[numpy.ndarray, torch.Tensor, warp.types.indexedarray]

Get the solver (velocity) iteration count for the articulations

The solver iteration count determines how accurately contacts, drives, and limits are resolved. Search for Solver Iteration Count in PhysX docs for more details.

Parameters

indices (Optional[Union[np.ndarray, List, torch.Tensor, wp.array]], optional) – indices to specify which prims to query. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

Returns

velocity iteration count. Shape (M,).

Return type

Union[np.ndarray, torch.Tensor, wp.indexedarray]

Example:

>>> # get all velocity iteration count. Returned shape is (5,) for the example: 5 envs
>>> prims.get_solver_velocity_iteration_counts()
[32 32 32 32 32]
>>>
>>> # get the velocity iteration count for the first, middle and last of the 5 envs. Returned shape is (3,)
>>> prims.get_solver_velocity_iteration_counts(indices=np.array([0, 2, 4]))
[32 32 32]
get_stabilization_thresholds(indices: Optional[Union[numpy.ndarray, List, torch.Tensor, warp.types.array]] = None) Union[numpy.ndarray, torch.Tensor, warp.types.indexedarray]

Get the mass-normalized kinetic energy below which the articulations may participate in stabilization

Search for Stabilization Threshold in PhysX docs for more details

Parameters

indices (Optional[Union[np.ndarray, List, torch.Tensor, wp.array]], optional) – indices to specify which prims to query. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

Returns

stabilization threshold. Shape (M,).

Return type

Union[np.ndarray, torch.Tensor, wp.indexedarray]

Example:

>>> # get all stabilization thresholds. Returned shape is (5,) for the example: 5 envs
>>> prims.get_solver_velocity_iteration_counts()
[0.001 0.001 0.001 0.001 0.001]
>>>
>>> # get the stabilization thresholds for the first, middle and last of the 5 envs. Returned shape is (3,)
>>> prims.get_solver_velocity_iteration_counts(indices=np.array([0, 2, 4]))
[0.001 0.001 0.001]
get_velocities(indices: Optional[Union[numpy.ndarray, list, torch.Tensor, warp.types.array]] = None, clone: bool = True) Union[numpy.ndarray, torch.Tensor, warp.types.indexedarray]

Get the linear and angular velocities of prims in the view.

Parameters
  • indices (Optional[Union[np.ndarray, list, torch.Tensor, wp.array]], optional) – indices to specify which prims to query. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view)

  • clone (bool, optional) – True to return a clone of the internal buffer. Otherwise False. Defaults to True.

Returns

linear and angular velocities of the prims in the view concatenated. shape is (M, 6). For the last dimension the first 3 values are for linear velocities and the last 3 for angular velocities

Return type

Union[np.ndarray, torch.Tensor, wp.indexedarray]

Example:

>>> # get all articulation velocities. Returned shape is (5, 6) for the example: 5 envs, linear (3) and angular (3)
>>> prims.get_velocities()
[[0. 0. 0. 0. 0. 0.]
 [0. 0. 0. 0. 0. 0.]
 [0. 0. 0. 0. 0. 0.]
 [0. 0. 0. 0. 0. 0.]
 [0. 0. 0. 0. 0. 0.]]
>>>
>>> # get only the articulation velocities for the first, middle and last of the 5 envs.
>>> # Returned shape is (3, 6) for the example: 3 envs selected, linear (3) and angular (3)
>>> prims.get_velocities(indices=np.array([0, 2, 4]))
[[0. 0. 0. 0. 0. 0.]
 [0. 0. 0. 0. 0. 0.]
 [0. 0. 0. 0. 0. 0.]]
get_visibilities(indices: Optional[Union[numpy.ndarray, list, torch.Tensor, warp.types.array]] = None) Union[numpy.ndarray, torch.Tensor, warp.types.indexedarray]

Returns the current visibilities of the prims in stage.

Parameters

indices (Optional[Union[np.ndarray, list, torch.Tensor, wp.array]], optional) – indices to specify which prims to query. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

Returns

Shape (M,) with type bool, where each item holds True

if the prim is visible in stage. False otherwise.

Return type

Union[np.ndarray, torch.Tensor, wp.indexedarray]

Example:

>>> # get all visibilities. Returned shape is (5,) for the example: 5 envs
>>> prims.get_visibilities()
[ True  True  True  True  True]
>>>
>>> # get the visibilities for the first, middle and last of the 5 envs. Returned shape is (3,)
>>> prims.get_visibilities(indices=np.array([0, 2, 4]))
[ True  True  True]
get_world_poses(indices: Optional[Union[numpy.ndarray, list, torch.Tensor, warp.types.array]] = None, clone: bool = True) Union[Tuple[numpy.ndarray, numpy.ndarray], Tuple[torch.Tensor, torch.Tensor], Tuple[warp.types.indexedarray, warp.types.indexedarray]]

Get the poses of the prims in the view with respect to the world’s frame.

Parameters
  • indices (Optional[Union[np.ndarray, list, torch.Tensor, wp.array]], optional) – indices to specify which prims to query. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

  • clone (bool, optional) – True to return a clone of the internal buffer. Otherwise False. Defaults to True.

Returns

first index is positions in the world frame of the prims. shape is (M, 3). Second index is quaternion orientations in the world frame of the prims. Quaternion is scalar-first (w, x, y, z). shape is (M, 4).

Return type

Union[Tuple[np.ndarray, np.ndarray], Tuple[torch.Tensor, torch.Tensor], Tuple[wp.indexedarray, wp.indexedarray]]

Example:

>>> # get all articulation poses with respect to the world's frame.
>>> # Returned shape is position (5, 3) and orientation (5, 4) for the example: 5 envs
>>> positions, orientations = prims.get_world_poses()
>>> positions
[[ 1.5000000e+00 -7.5000000e-01 -2.8610229e-08]
 [ 1.5000000e+00  7.5000000e-01 -2.8610229e-08]
 [-4.5299529e-08 -7.5000000e-01 -2.8610229e-08]
 [-4.5299529e-08  7.5000000e-01 -2.8610229e-08]
 [-1.5000000e+00 -7.5000000e-01 -2.8610229e-08]]
>>> orientations
[[1. 0. 0. 0.]
 [1. 0. 0. 0.]
 [1. 0. 0. 0.]
 [1. 0. 0. 0.]
 [1. 0. 0. 0.]]
>>>
>>> # get only the articulation poses with respect to the world's frame for the first, middle and last of the 5 envs.
>>> # Returned shape is position (3, 3) and orientation (3, 4) for the example: 3 envs selected
>>> positions, orientations = prims.get_world_poses(indices=np.array([0, 2, 4]))
>>> positions
[[ 1.5000000e+00 -7.5000000e-01 -2.8610229e-08]
 [-4.5299529e-08 -7.5000000e-01 -2.8610229e-08]
 [-1.5000000e+00 -7.5000000e-01 -2.8610229e-08]]
>>> orientations
[[1. 0. 0. 0.]
 [1. 0. 0. 0.]
 [1. 0. 0. 0.]]
get_world_scales(indices: Optional[Union[numpy.ndarray, list, torch.Tensor, warp.types.array]] = None) Union[numpy.ndarray, torch.Tensor, warp.types.indexedarray]

Get prim scales in the view with respect to the world’s frame

Parameters

indices (Optional[Union[np.ndarray, list, torch.Tensor, wp.array]], optional) – indices to specify which prims to query. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

Returns

scales applied to the prim’s dimensions in the world frame. shape is (M, 3).

Return type

Union[np.ndarray, torch.Tensor, wp.indexedarray]

Example:

>>> # get all prims scales with respect to the world's frame.
>>> # Returned shape is (5, 3) for the example: 5 envs
>>> prims.get_world_scales()
[[1. 1. 1.]
 [1. 1. 1.]
 [1. 1. 1.]
 [1. 1. 1.]
 [1. 1. 1.]]
>>>
>>> # get only the prims scales with respect to the world's frame for the first, middle and last of the 5 envs.
>>> # Returned shape is (3, 3) for the example: 3 envs selected
>>> prims.get_world_scales(indices=np.array([0, 2, 4]))
[[1. 1. 1.]
 [1. 1. 1.]
 [1. 1. 1.]]
initialize(physics_sim_view: Optional[omni.physics.tensors.bindings._physicsTensors.SimulationView] = None) None

Create a physics simulation view if not passed and set other properties using the PhysX tensor API

Note

If the articulation view has been added to the world scene (e.g., world.scene.add(prims)), it will be automatically initialized when the world is reset (e.g., world.reset()).

Warning

This method needs to be called after each hard reset (e.g., Stop + Play on the timeline) before interacting with any other class method.

Parameters

physics_sim_view (omni.physics.tensors.SimulationView, optional) – current physics simulation view. Defaults to None.

Example:

>>> prims.initialize()
property initialized: bool

Check if articulation view is initialized

Returns

True if the view object was initialized (after the first call of .initialize()). False otherwise.

Return type

bool

Example:

>>> # given an initialized articulation view
>>> prims.initialized
True

Returns: bool: True if the prim corresponds to a non root link in an articulation. Otherwise False.

is_physics_handle_valid() bool

Check if articulation view’s physics handler is initialized

Warning

If the physics handler is not valid many of the methods that requires PhysX will return None.

Returns

False if .initialize() needs to be called again for the physics handle to be valid. Otherwise True

Return type

bool

Example:

>>> prims.is_physics_handle_valid()
True
is_valid(indices: Optional[Union[numpy.ndarray, list, torch.Tensor, warp.types.array]] = None) bool

Check that all prims have a valid USD Prim

Parameters

indices (Optional[Union[np.ndarray, list, torch.Tensor, wp.array]], optional) – indices to specify which prims to query. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

Returns

True if all prim paths specified in the view correspond to a valid prim in stage. False otherwise.

Return type

bool

Example:

>>> prims.is_valid()
True
is_visual_material_applied(indices: Optional[Union[numpy.ndarray, list, torch.Tensor, warp.types.array]] = None) List[bool]

Check if there is a visual material applied

Parameters

indices (Optional[Union[np.ndarray, list, torch.Tensor, wp.array]], optional) – indices to specify which prims to query. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

Returns

True if there is a visual material applied is applied to the corresponding prim in the view. False otherwise.

Return type

List[bool]

Example:

>>> # given a visual material that is applied only to the first and the last environment
>>> prims.is_visual_material_applied()
[True, False, False, False, True]
>>>
>>> # check for the first, middle and last of the 5 envs
>>> prims.is_visual_material_applied(indices=np.array([0, 2, 4]))
[True, False, True]
property joint_names: List[str]

List of prim names for each joint of the articulations

Returns

ordered names of joints that corresponds to degrees of freedom for the articulations in the view

Return type

List[str]

property name: str

Returns: str: name given to the prims view when instantiating it.

property num_bodies: int

Number of rigid bodies (links) of the articulations

Returns

maximum number of rigid bodies for the articulations in the view

Return type

int

Example:

>>> prims.num_bodies
12
property num_dof: int

Number of DOF of the articulations

Returns

maximum number of DOFs for the articulations in the view

Return type

int

Example:

>>> prims.num_dof
9
property num_fixed_tendons: int

Number of fixed tendons of the articulations

Returns

maximum number of fixed tendons for the articulations in the view

Return type

int

Example:

>>> prims.num_fixed_tendons
0
property num_joints: int

Number of joints of the articulations

Returns

number of joints of the articulations in the view

Return type

int

property num_shapes: int

Number of rigid shapes of the articulations

Returns

maximum number of rigid shapes for the articulations in the view

Return type

int

Example:

>>> prims.num_shapes
17
post_reset() None

Reset the robots to their default states

Note

For the robots, in addition to configuring the root prim’s default positions and spatial orientations (defined via the set_default_state method), the joint’s positions, velocities, and efforts (defined via the set_joints_default_state method) and the joint’s stiffness and dampings (defined via the set_gains method) are imposed

Example:

>>> prims.post_reset()
property prim_paths: List[str]
Returns

list of prim paths in the stage encapsulated in this view.

Return type

List[str]

Example:

>>> prims.prim_paths
['/World/envs/env_0', '/World/envs/env_1', '/World/envs/env_2', '/World/envs/env_3', '/World/envs/env_4']
property prims: List[pxr.Usd.Prim]
Returns

List of USD Prim objects encapsulated in this view.

Return type

List[Usd.Prim]

Example:

>>> prims.prims
[Usd.Prim(</World/envs/env_0>), Usd.Prim(</World/envs/env_1>), Usd.Prim(</World/envs/env_2>),
 Usd.Prim(</World/envs/env_3>), Usd.Prim(</World/envs/env_4>)]
set_angular_velocities(velocities: Optional[Union[numpy.ndarray, torch.Tensor, warp.types.array]] = None, indices: Optional[Union[numpy.ndarray, list, torch.Tensor, warp.types.array]] = None) None

Set the angular velocities of the prims in the view

The method does this through the physx API only. It has to be called after initialization. Note: This method is not supported for the gpu pipeline. set_velocities method should be used instead.

Warning

This method will immediately set the articulation state

Parameters
  • velocities (Optional[Union[np.ndarray, torch.Tensor, wp.array]]) – angular velocities to set the rigid prims to. shape is (M, 3).

  • indices (Optional[Union[np.ndarray, list, torch.Tensor, wp.array]], optional) – indices to specify which prims to manipulate. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

Hint

This method belongs to the methods used to set the articulation kinematic state:

set_velocities (set_linear_velocities, set_angular_velocities), set_joint_positions, set_joint_velocities, set_joint_efforts

Example:

>>> # set each articulation linear velocity to (0.1, 0.1, 0.1)
>>> velocities = np.full((num_envs, 3), fill_value=0.1)
>>> prims.set_angular_velocities(velocities)
>>>
>>> # set only the articulation linear velocities for the first, middle and last of the 5 envs
>>> velocities = np.full((3, 3), fill_value=0.1)
>>> prims.set_angular_velocities(velocities, indices=np.array([0, 2, 4]))
set_armatures(values: Union[numpy.ndarray, torch.Tensor, warp.types.array], indices: Optional[Union[numpy.ndarray, List, torch.Tensor, warp.types.array]] = None, joint_indices: Optional[Union[numpy.ndarray, List, torch.Tensor, warp.types.array]] = None) None

Set armatures for articulation joints in the view

Search for “Joint Armature” in PhysX docs for more details.

Parameters
  • values (Union[np.ndarray, torch.Tensor, wp.array]) – armatures for articulation joints in the view. shape (M, K).

  • indices (Optional[Union[np.ndarray, List, torch.Tensor, wp.array]], optional) – indices to specify which prims to manipulate. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

  • joint_indices (Optional[Union[np.ndarray, List, torch.Tensor, wp.array]], optional) – joint indices to specify which joints to manipulate. Shape (K,). Where K <= num of dofs. Defaults to None (i.e: all dofs).

Example:

>>> # set all joint armatures to 0.05 for all envs
>>> prims.set_armatures(np.full((num_envs, prims.num_dof), 0.05))
>>>
>>> # set only the finger joint (panda_finger_joint1 (7) and panda_finger_joint2 (8)) armatures
>>> # for the first, middle and last of the 5 envs to 0.05
>>> prims.set_armatures(np.full((3, 2), 0.05), indices=np.array([0,2,4]), joint_indices=np.array([7,8]))
set_body_coms(positions: Optional[Union[numpy.ndarray, torch.Tensor, warp.types.array]] = None, orientations: Optional[Union[numpy.ndarray, torch.Tensor, warp.types.array]] = None, indices: Optional[Union[numpy.ndarray, List, torch.Tensor, warp.types.array]] = None, body_indices: Optional[Union[numpy.ndarray, List, torch.Tensor, warp.types.array]] = None) None

Set body center of mass (COM) positions and orientations for articulation bodies in the view.

Parameters
  • positions (Union[np.ndarray, torch.Tensor, wp.array]) – body center of mass positions for articulations in the view. shape (M, K, 3).

  • orientations (Union[np.ndarray, torch.Tensor, wp.array]) – body center of mass orientations for articulations in the view. shape (M, K, 4).

  • indices (Optional[Union[np.ndarray, List, torch.Tensor, wp.array]], optional) – indices to specify which prims to manipulate. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

  • body_indices (Optional[Union[np.ndarray, List, torch.Tensor, wp.array]], optional) – body indices to specify which bodies to manipulate. Shape (K,). Where K <= num of bodies. Defaults to None (i.e: all bodies).

Example:

>>> # set the center of mass for all the articulation rigid bodies to the indicated values.
>>> # Since there are 5 envs, the inertias are repeated 5 times
>>> positions = np.tile(np.array([0.01, 0.02, 0.03]), (num_envs, prims.num_bodies, 1))
>>> orientations = np.tile(np.array([1.0, 0.0, 0.0, 0.0]), (num_envs, prims.num_bodies, 1))
>>> prims.set_body_coms(positions, orientations)
>>>
>>> # set the fingers center of mass: panda_leftfinger (10) and panda_rightfinger (11) to 0.2
>>> # for the first, middle and last of the 5 envs
>>> positions = np.tile(np.array([0.01, 0.02, 0.03]), (3, 2, 1))
>>> orientations = np.tile(np.array([1.0, 0.0, 0.0, 0.0]), (3, 2, 1))
>>> prims.set_body_coms(positions, orientations, indices=np.array([0, 2, 4]), body_indices=np.array([10, 11]))
set_body_inertias(values: Union[numpy.ndarray, torch.Tensor, warp.types.array], indices: Optional[Union[numpy.ndarray, List, torch.Tensor, warp.types.array]] = None, body_indices: Optional[Union[numpy.ndarray, List, torch.Tensor, warp.types.array]] = None) None

Set body inertias for articulation bodies in the view.

Parameters
  • values (Union[np.ndarray, torch.Tensor, wp.array]) – body inertias for articulations in the view. shape (M, K, 9).

  • indices (Optional[Union[np.ndarray, List, torch.Tensor, wp.array]], optional) – indices to specify which prims to manipulate. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

  • body_indices (Optional[Union[np.ndarray, List, torch.Tensor, wp.array]], optional) – body indices to specify which bodies to manipulate. Shape (K,). Where K <= num of bodies. Defaults to None (i.e: all bodies).

Example:

>>> # set the inertias for all the articulation rigid bodies to the indicated values.
>>> # Since there are 5 envs, the inertias are repeated 5 times
>>> inertias = np.tile(np.array([0.1, 0.0, 0.0, 0.0, 0.1, 0.0, 0.0, 0.0, 0.1]), (num_envs, prims.num_bodies, 1))
>>> prims.set_body_inertias(inertias)
>>>
>>> # set the fingers inertias: panda_leftfinger (10) and panda_rightfinger (11) to 0.2
>>> # for the first, middle and last of the 5 envs
>>> inertias = np.tile(np.array([0.1, 0.0, 0.0, 0.0, 0.1, 0.0, 0.0, 0.0, 0.1]), (3, 2, 1))
>>> prims.set_body_inertias(inertias, indices=np.array([0, 2, 4]), body_indices=np.array([10, 11]))
set_body_masses(values: Union[numpy.ndarray, torch.Tensor, warp.types.array], indices: Optional[Union[numpy.ndarray, List, torch.Tensor, warp.types.array]] = None, body_indices: Optional[Union[numpy.ndarray, List, torch.Tensor, warp.types.array]] = None) None

Set body masses for articulation bodies in the view

Parameters
  • values (Union[np.ndarray, torch.Tensor, wp.array]) – body masses for articulations in the view. shape (M, K).

  • indices (Optional[Union[np.ndarray, List, torch.Tensor, wp.array]], optional) – indices to specify which prims to manipulate. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

  • body_indices (Optional[Union[np.ndarray, List, torch.Tensor, wp.array]], optional) – body indices to specify which bodies to manipulate. Shape (K,). Where K <= num of bodies. Defaults to None (i.e: all bodies).

Example:

>>> # set the masses for all the articulation rigid bodies to the indicated values.
>>> # Since there are 5 envs, the masses are repeated 5 times
>>> masses = np.tile(np.array([1.2, 1.1, 1.0, 0.9, 0.8, 0.7, 0.6, 0.5, 0.4, 0.3, 0.2, 0.2]), (num_envs, 1))
>>> prims.set_body_masses(masses)
>>>
>>> # set the fingers masses: panda_leftfinger (10) and panda_rightfinger (11) to 0.2
>>> # for the first, middle and last of the 5 envs
>>> masses = np.tile(np.array([0.2, 0.2]), (3, 1))
>>> prims.set_body_masses(masses, indices=np.array([0, 2, 4]), body_indices=np.array([10, 11]))
set_default_state(positions: Optional[Union[numpy.ndarray, torch.Tensor, warp.types.array]] = None, orientations: Optional[Union[numpy.ndarray, torch.Tensor, warp.types.array]] = None, indices: Optional[Union[numpy.ndarray, list, torch.Tensor, warp.types.array]] = None) None

Set the default state of the prims (positions and orientations), that will be used after each reset.

Note

The default states will be set during post-reset (e.g., calling .post_reset() or world.reset() methods)

Parameters
  • positions (Optional[Union[np.ndarray, torch.Tensor, wp.array]], optional) – positions in the world frame of the prim. shape is (M, 3). Defaults to None, which means left unchanged.

  • orientations (Optional[Union[np.ndarray, torch.Tensor, wp.array]], optional) – quaternion orientations in the world frame of the prim. quaternion is scalar-first (w, x, y, z). shape is (M, 4). Defaults to None, which means left unchanged.

  • indices (Optional[Union[np.ndarray, list, torch.Tensor, wp.array]], optional) – indices to specify which prims to manipulate. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

Example:

>>> # configure default states for all prims
>>> positions = np.zeros((num_envs, 3))
>>> positions[:, 0] = np.arange(num_envs)
>>> orientations = np.tile(np.array([1.0, 0.0, 0.0, 0.0]), (num_envs, 1))
>>> prims.set_default_state(positions=positions, orientations=orientations)
>>>
>>> # set default states during post-reset
>>> prims.post_reset()
set_effort_modes(mode: str, indices: Optional[Union[numpy.ndarray, List, torch.Tensor, warp.types.array]] = None, joint_indices: Optional[Union[numpy.ndarray, List, torch.Tensor]] = None) None

Set effort modes for articulations in the view

Parameters
  • mode (str) – effort mode to be applied to prims in the view: acceleration or force.

  • indices (Optional[Union[np.ndarray, List, torch.Tensor, wp.array]], optional) – indices to specify which prims to manipulate. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

  • joint_indices (Optional[Union[np.ndarray, List, torch.Tensor, wp.array]], optional) – joint indices to specify which joints to manipulate. Shape (K,). Where K <= num of dofs. Defaults to None (i.e: all dofs).

Example:

>>> # set the effort mode for all joints to 'force'
>>> prims.set_effort_modes("force")
>>>
>>> # set only the finger joints effort mode to 'force' for the first, middle and last of the 5 envs
>>> prims.set_effort_modes("force", indices=np.array([0, 2, 4]), joint_indices=np.array([7, 8]))
set_enabled_self_collisions(flags: Union[numpy.ndarray, torch.Tensor, warp.types.array], indices: Optional[Union[numpy.ndarray, List, torch.Tensor, warp.types.array]] = None) None

Set the enable self collisions flag (physxArticulation:enabledSelfCollisions)

Parameters
  • flags (Union[np.ndarray, torch.Tensor, wp.array]) – true to enable self collision. otherwise false. shape (M,)

  • indices (Optional[Union[np.ndarray, List, torch.Tensor, wp.array]], optional) – indices to specify which prims to manipulate. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

Example:

>>> # enable the self collisions flag for all envs
>>> prims.set_enabled_self_collisions(np.full((num_envs,), True))
>>>
>>> # enable the self collisions flag only for the first, middle and last of the 5 envs
>>> prims.set_enabled_self_collisions(np.full((3,), True), indices=np.array([0, 2, 4]))
set_fixed_tendon_properties(stiffnesses: Optional[Union[numpy.ndarray, torch.Tensor, warp.types.array]] = None, dampings: Optional[Union[numpy.ndarray, torch.Tensor, warp.types.array]] = None, limit_stiffnesses: Optional[Union[numpy.ndarray, torch.Tensor, warp.types.array]] = None, limits: Optional[Union[numpy.ndarray, torch.Tensor, warp.types.array]] = None, rest_lengths: Optional[Union[numpy.ndarray, torch.Tensor, warp.types.array]] = None, offsets: Optional[Union[numpy.ndarray, torch.Tensor, warp.types.array]] = None, indices: Optional[Union[numpy.ndarray, List, torch.Tensor, warp.types.array]] = None) None

Set fixed tendon properties for articulations in the view

Search for Fixed Tendon in PhysX docs for more details

Parameters
  • stiffnesses (Union[np.ndarray, torch.Tensor, wp.array]) – fixed tendon stiffnesses for articulations in the view. shape (M, K).

  • dampings (Union[np.ndarray, torch.Tensor, wp.array]) – fixed tendon dampings for articulations in the view. shape (M, K).

  • limit_stiffnesses (Union[np.ndarray, torch.Tensor, wp.array]) – fixed tendon limit stiffnesses for articulations in the view. shape (M, K).

  • limits (Union[np.ndarray, torch.Tensor, wp.array]) – fixed tendon limits for articulations in the view. shape (M, K, 2).

  • rest_lengths (Union[np.ndarray, torch.Tensor, wp.array]) – fixed tendon rest lengths for articulations in the view. shape (M, K).

  • offsets (Union[np.ndarray, torch.Tensor, wp.array]) – fixed tendon offsets for articulations in the view. shape (M, K).

  • indices (Optional[Union[np.ndarray, List, torch.Tensor, wp.array]], optional) – indices to specify which prims to manipulate. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

Example:

>>> # set the limit stiffnesses and dampings
>>> # for the ShadowHand articulation that has 4 fixed tendons (prims.num_fixed_tendons)
>>> limit_stiffnesses = np.full((num_envs, prims.num_fixed_tendons), fill_value=10.0)
>>> dampings = np.full((num_envs, prims.num_fixed_tendons), fill_value=0.1)
>>> prims.set_fixed_tendon_properties(dampings=dampings, limit_stiffnesses=limit_stiffnesses)
set_friction_coefficients(values: Union[numpy.ndarray, torch.Tensor], indices: Optional[Union[numpy.ndarray, List, torch.Tensor, warp.types.array]] = None, joint_indices: Optional[Union[numpy.ndarray, List, torch.Tensor, warp.types.array]] = None) None

Set the friction coefficients for articulation joints in the view

Search for “Joint Friction Coefficient” in PhysX docs for more details.

Parameters
  • values (Union[np.ndarray, torch.Tensor, wp.array]) – friction coefficients for articulation joints in the view. shape (M, K).

  • indices (Optional[Union[np.ndarray, List, torch.Tensor, wp.array]], optional) – indices to specify which prims to manipulate. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

  • joint_indices (Optional[Union[np.ndarray, List, torch.Tensor, wp.array]], optional) – joint indices to specify which joints to manipulate. Shape (K,). Where K <= num of dofs. Defaults to None (i.e: all dofs).

Example:

>>> # set all joint friction coefficients to 0.05 for all envs
>>> prims.set_friction_coefficients(np.full((num_envs, prims.num_dof), 0.05))
>>>
>>> # set only the finger joint (panda_finger_joint1 (7) and panda_finger_joint2 (8)) friction coefficients
>>> # for the first, middle and last of the 5 envs to 0.05
>>> prims.set_friction_coefficients(np.full((3, 2), 0.05), indices=np.array([0,2,4]), joint_indices=np.array([7,8]))
set_gains(kps: Optional[Union[numpy.ndarray, torch.Tensor, warp.types.array]] = None, kds: Optional[Union[numpy.ndarray, torch.Tensor, warp.types.array]] = None, indices: Optional[Union[numpy.ndarray, List, torch.Tensor, warp.types.array]] = None, joint_indices: Optional[Union[numpy.ndarray, List, torch.Tensor, warp.types.array]] = None, save_to_usd: bool = False) None

Set the implicit Proportional-Derivative (PD) controller’s Kps (stiffnesses) and Kds (dampings) of articulations in the view

Parameters
  • kps (Optional[Union[np.ndarray, torch.Tensor, wp.array]], optional) – stiffness of the drives. shape is (M, K). Defaults to None.

  • kds (Optional[Union[np.ndarray, torch.Tensor, wp.array]], optional) – damping of the drives. shape is (M, K).. Defaults to None.

  • indices (Optional[Union[np.ndarray, List, torch.Tensor, wp.array]], optional) – indices to specify which prims to manipulate. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

  • joint_indices (Optional[Union[np.ndarray, List, torch.Tensor, wp.array]], optional) – joint indices to specify which joints to manipulate. Shape (K,). Where K <= num of dofs. Defaults to None (i.e: all dofs).

  • save_to_usd (bool, optional) – True to save the gains in the usd. otherwise False.

Example:

>>> # set the gains (stiffnesses and dampings) for all the articulation joints to the indicated values.
>>> # Since there are 5 envs, the gains are repeated 5 times
>>> stiffnesses = np.tile(np.array([100000, 100000, 100000, 100000, 80000, 80000, 80000, 50000, 50000]), (num_envs, 1))
>>> dampings = np.tile(np.array([8000, 8000, 8000, 8000, 5000, 5000, 5000, 2000, 2000]), (num_envs, 1))
>>> prims.set_gains(kps=stiffnesses, kds=dampings)
>>>
>>> # set the fingers gains (stiffnesses and dampings): panda_finger_joint1 (7) and panda_finger_joint2 (8)
>>> # to 50000 and 2000 respectively for the first, middle and last of the 5 envs
>>> stiffnesses = np.tile(np.array([50000, 50000]), (3, 1))
>>> dampings = np.tile(np.array([2000, 2000]), (3, 1))
>>> prims.set_gains(kps=stiffnesses, kds=dampings, indices=np.array([0, 2, 4]), joint_indices=np.array([7, 8]))
set_joint_efforts(efforts: Optional[Union[numpy.ndarray, torch.Tensor, warp.types.array]], indices: Optional[Union[numpy.ndarray, List, torch.Tensor, warp.types.array]] = None, joint_indices: Optional[Union[numpy.ndarray, List, torch.Tensor, warp.types.array]] = None) None

Set the joint efforts of articulations in the view

Note

This method can be used for effort control. For this purpose, there must be no joint drive or the stiffness and damping must be set to zero.

Parameters
  • efforts (Optional[Union[np.ndarray, torch.Tensor, wp.array]]) – efforts of articulations in the view to be set to in the next frame. shape is (M, K).

  • indices (Optional[Union[np.ndarray, List, torch.Tensor, wp.array]], optional) – indices to specify which prims to manipulate. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

  • joint_indices (Optional[Union[np.ndarray, List, torch.Tensor, wp.array]], optional) – joint indices to specify which joints to manipulate. Shape (K,). Where K <= num of dofs. Defaults to None (i.e: all dofs).

Hint

This method belongs to the methods used to set the articulation kinematic states:

set_velocities (set_linear_velocities, set_angular_velocities), set_joint_positions, set_joint_velocities, set_joint_efforts

Example:

>>> # set the efforts for all the articulation joints to the indicated values.
>>> # Since there are 5 envs, the joint efforts are repeated 5 times
>>> efforts = np.tile(np.array([10, 20, 30, 40, 50, 60, 70, 80, 90]), (num_envs, 1))
>>> prims.set_joint_efforts(efforts)
>>>
>>> # set the fingers efforts: panda_finger_joint1 (7) and panda_finger_joint2 (8) to 10
>>> # for the first, middle and last of the 5 envs
>>> efforts = np.tile(np.array([10, 10]), (3, 1))
>>> prims.set_joint_efforts(efforts, indices=np.array([0, 2, 4]), joint_indices=np.array([7, 8]))
set_joint_position_targets(positions: Optional[Union[numpy.ndarray, torch.Tensor, warp.types.array]], indices: Optional[Union[numpy.ndarray, List, torch.Tensor, warp.types.array]] = None, joint_indices: Optional[Union[numpy.ndarray, List, torch.Tensor, warp.types.array]] = None) None

Set the joint position targets for the implicit Proportional-Derivative (PD) controllers

Note

This is an independent method for controlling joints. To apply multiple targets (position, velocity, and/or effort) in the same call, consider using the apply_action method

Parameters
  • positions (Optional[Union[np.ndarray, torch.Tensor, wp.array]]) – joint position targets for the implicit PD controller. shape is (M, K).

  • indices (Optional[Union[np.ndarray, List, torch.Tensor, wp.array]], optional) – indices to specify which prims to manipulate. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

  • joint_indices (Optional[Union[np.ndarray, List, torch.Tensor, wp.array]], optional) – joint indices to specify which joints to manipulate. Shape (K,). Where K <= num of dofs. Defaults to None (i.e: all dofs).

Hint

High stiffness makes the joints snap faster and harder to the desired target, and higher damping smoothes but also slows down the joint’s movement to target

  • For position control, set relatively high stiffness and low damping (to reduce vibrations)

Example:

>>> # apply the target positions (to move all the robot joints) to the indicated values.
>>> # Since there are 5 envs, the joint positions are repeated 5 times
>>> positions = np.tile(np.array([0.0, -1.0, 0.0, -2.2, 0.0, 2.4, 0.8, 0.04, 0.04]), (num_envs, 1))
>>> prims.set_joint_position_targets(positions)
>>>
>>> # close the robot fingers: panda_finger_joint1 (7) and panda_finger_joint2 (8) to 0.0
>>> # for the first, middle and last of the 5 envs
>>> positions = np.tile(np.array([0.0, 0.0]), (3, 1))
>>> prims.set_joint_position_targets(positions, indices=np.array([0, 2, 4]), joint_indices=np.array([7, 8]))
set_joint_positions(positions: Optional[Union[numpy.ndarray, torch.Tensor, warp.types.array]], indices: Optional[Union[numpy.ndarray, List, torch.Tensor, warp.types.array]] = None, joint_indices: Optional[Union[numpy.ndarray, List, torch.Tensor, warp.types.array]] = None) None

Set the joint positions of articulations in the view

Warning

This method will immediately set (teleport) the affected joints to the indicated value. Use the set_joint_position_targets or the apply_action methods to control the articulation joints.

Parameters
  • positions (Optional[Union[np.ndarray, torch.Tensor, wp.array]]) – joint positions of articulations in the view to be set to in the next frame. shape is (M, K).

  • indices (Optional[Union[np.ndarray, List, torch.Tensor, wp.array]], optional) – indices to specify which prims to manipulate. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

  • joint_indices (Optional[Union[np.ndarray, List, torch.Tensor, wp.array]], optional) – joint indices to specify which joints to manipulate. Shape (K,). Where K <= num of dofs. Defaults to None (i.e: all dofs).

Hint

This method belongs to the methods used to set the articulation kinematic states:

set_velocities (set_linear_velocities, set_angular_velocities), set_joint_positions, set_joint_velocities, set_joint_efforts

Example:

>>> # set all the articulation joints.
>>> # Since there are 5 envs, the joint positions are repeated 5 times
>>> positions = np.tile(np.array([0.0, -1.0, 0.0, -2.2, 0.0, 2.4, 0.8, 0.04, 0.04]), (num_envs, 1))
>>> prims.set_joint_positions(positions)
>>>
>>> # set only the fingers in closed position: panda_finger_joint1 (7) and panda_finger_joint2 (8) to 0.0
>>> # for the first, middle and last of the 5 envs
>>> positions = np.tile(np.array([0.0, 0.0]), (3, 1))
>>> prims.set_joint_positions(positions, indices=np.array([0, 2, 4]), joint_indices=np.array([7, 8]))
set_joint_velocities(velocities: Optional[Union[numpy.ndarray, torch.Tensor, warp.types.array]], indices: Optional[Union[numpy.ndarray, List, torch.Tensor, warp.types.array]] = None, joint_indices: Optional[Union[numpy.ndarray, List, torch.Tensor, warp.types.array]] = None) None

Set the joint velocities of articulations in the view

Warning

This method will immediately set the affected joints to the indicated value. Use the set_joint_velocity_targets or the apply_action methods to control the articulation joints.

Parameters
  • velocities (Optional[Union[np.ndarray, torch.Tensor, wp.array]]) – joint velocities of articulations in the view to be set to in the next frame. shape is (M, K).

  • indices (Optional[Union[np.ndarray, List, torch.Tensor, wp.array]], optional) – indices to specify which prims to manipulate. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

  • joint_indices (Optional[Union[np.ndarray, List, torch.Tensor, wp.array]], optional) – joint indices to specify which joints to manipulate. Shape (K,). Where K <= num of dofs. Defaults to None (i.e: all dofs).

Hint

This method belongs to the methods used to set the articulation kinematic states:

set_velocities (set_linear_velocities, set_angular_velocities), set_joint_positions, set_joint_velocities, set_joint_efforts

Example:

>>> # set the velocities for all the articulation joints to the indicated values.
>>> # Since there are 5 envs, the joint velocities are repeated 5 times
>>> velocities = np.tile(np.array([0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, 0.9]), (num_envs, 1))
>>> prims.set_joint_velocities(velocities)
>>>
>>> # set the fingers velocities: panda_finger_joint1 (7) and panda_finger_joint2 (8) to -0.1
>>> # for the first, middle and last of the 5 envs
>>> velocities = np.tile(np.array([-0.1, -0.1]), (3, 1))
>>> prims.set_joint_velocities(velocities, indices=np.array([0, 2, 4]), joint_indices=np.array([7, 8]))
set_joint_velocity_targets(velocities: Optional[Union[numpy.ndarray, torch.Tensor, warp.types.array]], indices: Optional[Union[numpy.ndarray, List, torch.Tensor, warp.types.array]] = None, joint_indices: Optional[Union[numpy.ndarray, List, torch.Tensor, warp.types.array]] = None) None

Set the joint velocity targets for the implicit Proportional-Derivative (PD) controllers

Note

This is an independent method for controlling joints. To apply multiple targets (position, velocity, and/or effort) in the same call, consider using the apply_action method

Parameters
  • velocities (Optional[Union[np.ndarray, torch.Tensor, wp.array]]) – joint velocity targets for the implicit PD controller. shape is (M, K).

  • indices (Optional[Union[np.ndarray, List, torch.Tensor, wp.array]], optional) – indices to specify which prims to manipulate. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

  • joint_indices (Optional[Union[np.ndarray, List, torch.Tensor, wp.array]], optional) – joint indices to specify which joints to manipulate. Shape (K,). Where K <= num of dofs. Defaults to None (i.e: all dofs).

Hint

High stiffness makes the joints snap faster and harder to the desired target, and higher damping smoothes but also slows down the joint’s movement to target

  • For velocity control, stiffness must be set to zero with a non-zero damping

Example:

>>> # apply the target velocities for all the articulation joints to the indicated values.
>>> # Since there are 5 envs, the joint velocities are repeated 5 times
>>> velocities = np.tile(np.array([0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, 0.9]), (num_envs, 1))
>>> prims.set_joint_velocity_targets(velocities)
>>>
>>> # apply the fingers target velocities: panda_finger_joint1 (7) and panda_finger_joint2 (8) to -1.0
>>> # for the first, middle and last of the 5 envs
>>> velocities = np.tile(np.array([-0.1, -0.1]), (3, 1))
>>> prims.set_joint_velocity_targets(velocities, indices=np.array([0, 2, 4]), joint_indices=np.array([7, 8]))
set_joints_default_state(positions: Optional[Union[numpy.ndarray, torch.Tensor, warp.types.array]] = None, velocities: Optional[Union[numpy.ndarray, torch.Tensor, warp.types.array]] = None, efforts: Optional[Union[numpy.ndarray, torch.Tensor, warp.types.array]] = None) None

Set the joints default state (joint positions, velocities and efforts) to be applied after each reset.

Note

The default states will be set during post-reset (e.g., calling .post_reset() or world.reset() methods)

Parameters
  • positions (Optional[Union[np.ndarray, torch.Tensor, wp.array]], optional) – default joint positions. shape is (N, num of dofs). Defaults to None.

  • velocities (Optional[Union[np.ndarray, torch.Tensor, wp.array]], optional) – default joint velocities. shape is (N, num of dofs). Defaults to None.

  • efforts (Optional[Union[np.ndarray, torch.Tensor, wp.array]], optional) – default joint efforts. shape is (N, num of dofs). Defaults to None.

Example:

>>> # configure default joint states for all articulations
>>> positions = np.tile(np.array([0.0, -1.0, 0.0, -2.2, 0.0, 2.4, 0.8, 0.04, 0.04]), (num_envs, 1))
>>> prims.set_joints_default_state(
...     positions=positions,
...     velocities=np.zeros((num_envs, prims.num_dof)),
...     efforts=np.zeros((num_envs, prims.num_dof))
... )
>>>
>>> # set default states during post-reset
>>> prims.post_reset()
set_linear_velocities(velocities: Optional[Union[numpy.ndarray, torch.Tensor, warp.types.array]] = None, indices: Optional[Union[numpy.ndarray, list, torch.Tensor, warp.types.array]] = None) None

Set the linear velocities of the prims in the view

The method does this through the PhysX API only. It has to be called after initialization. Note: This method is not supported for the gpu pipeline. set_velocities method should be used instead.

Warning

This method will immediately set the articulation state

Parameters
  • velocities (Optional[Union[np.ndarray, torch.Tensor, wp.array]]) – linear velocities to set the rigid prims to. shape is (M, 3).

  • indices (Optional[Union[np.ndarray, list, torch.Tensor, wp.array]], optional) – indices to specify which prims to manipulate. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

Hint

This method belongs to the methods used to set the articulation kinematic state:

set_velocities (set_linear_velocities, set_angular_velocities), set_joint_positions, set_joint_velocities, set_joint_efforts

Example:

>>> # set each articulation linear velocity to (1.0, 1.0, 1.0)
>>> velocities = np.ones((num_envs, 3))
>>> prims.set_linear_velocities(velocities)
>>>
>>> # set only the articulation linear velocities for the first, middle and last of the 5 envs
>>> velocities = np.ones((3, 3))
>>> prims.set_linear_velocities(velocities, indices=np.array([0, 2, 4]))
set_local_poses(translations: Optional[Union[numpy.ndarray, torch.Tensor, warp.types.array]] = None, orientations: Optional[Union[numpy.ndarray, torch.Tensor, warp.types.array]] = None, indices: Optional[Union[numpy.ndarray, list, torch.Tensor, warp.types.array]] = None) None

Set prim poses in the view with respect to the local frame (the prim’s parent frame).

Warning

This method will change (teleport) the prim poses immediately to the indicated value

Parameters
  • translations (Optional[Union[np.ndarray, torch.Tensor, wp.array]], optional) – translations in the local frame of the prims (with respect to its parent prim). shape is (M, 3). Defaults to None, which means left unchanged.

  • orientations (Optional[Union[np.ndarray, torch.Tensor, wp.array]], optional) – quaternion orientations in the local frame of the prims. quaternion is scalar-first (w, x, y, z). shape is (M, 4). Defaults to None, which means left unchanged.

  • indices (Optional[Union[np.ndarray, list, torch.Tensor, wp.array]], optional) – indices to specify which prims to manipulate. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

Hint

This method belongs to the methods used to set the prim state

Example:

>>> # reposition all articulations
>>> positions = np.zeros((num_envs, 3))
>>> positions[:,0] = np.arange(num_envs)
>>> orientations = np.tile(np.array([1.0, 0.0, 0.0, 0.0]), (num_envs, 1))
>>> prims.set_local_poses(positions, orientations)
>>>
>>> # reposition only the articulations for the first, middle and last of the 5 envs
>>> positions = np.zeros((3, 3))
>>> positions[:,1] = np.arange(3)
>>> orientations = np.tile(np.array([1.0, 0.0, 0.0, 0.0]), (3, 1))
>>> prims.set_local_poses(positions, orientations, indices=np.array([0, 2, 4]))
set_local_scales(scales: Optional[Union[numpy.ndarray, torch.Tensor, warp.types.array]], indices: Optional[Union[numpy.ndarray, list, torch.Tensor, warp.types.array]] = None) None

Set prim scales in the view with respect to the local frame (the prim’s parent frame)

Parameters
  • scales (Optional[Union[np.ndarray, torch.Tensor, wp.array]]) – scales to be applied to the prim’s dimensions in the view. shape is (M, 3).

  • indices (Optional[Union[np.ndarray, list, torch.Tensor, wp.array]], optional) – indices to specify which prims to manipulate. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

Example:

>>> # set the scale for all prims. Since there are 5 envs, the scale is repeated 5 times
>>> scales = np.tile(np.array([1.0, 0.75, 0.5]), (num_envs, 1))
>>> prims.set_local_scales(scales)
>>>
>>> # set the scale for the first, middle and last of the 5 envs
>>> scales = np.tile(np.array([1.0, 0.75, 0.5]), (3, 1))
>>> prims.set_local_scales(scales, indices=np.array([0, 2, 4]))
set_max_efforts(values: Union[numpy.ndarray, torch.Tensor, warp.types.array], indices: Optional[Union[numpy.ndarray, List, torch.Tensor, warp.types.array]] = None, joint_indices: Optional[Union[numpy.ndarray, List, torch.Tensor, warp.types.array]] = None) None

Set maximum efforts for articulation in the view

Parameters
  • values (Union[np.ndarray, torch.Tensor, wp.array]) – maximum efforts for articulations in the view. shape (M, K).

  • indices (Optional[Union[np.ndarray, List, torch.Tensor, wp.array]], optional) – indices to specify which prims to manipulate. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

  • joint_indices (Optional[Union[np.ndarray, List, torch.Tensor, wp.array]], optional) – joint indices to specify which joints to manipulate. Shape (K,). Where K <= num of dofs. Defaults to None (i.e: all dofs).

Example:

>>> # set the max efforts for all the articulation joints to the indicated values.
>>> # Since there are 5 envs, the joint efforts are repeated 5 times
>>> max_efforts = np.tile(np.array([10000, 9000, 8000, 7000, 6000, 5000, 4000, 1000, 1000]), (num_envs, 1))
>>> prims.set_max_efforts(max_efforts)
>>>
>>> # set the fingers max efforts: panda_finger_joint1 (7) and panda_finger_joint2 (8) to 1000
>>> # for the first, middle and last of the 5 envs
>>> max_efforts = np.tile(np.array([1000, 1000]), (3, 1))
>>> prims.set_max_efforts(max_efforts, indices=np.array([0, 2, 4]), joint_indices=np.array([7, 8]))
set_sleep_thresholds(thresholds: Union[numpy.ndarray, torch.Tensor, warp.types.array], indices: Optional[Union[numpy.ndarray, List, torch.Tensor, warp.types.array]] = None) None

Set the threshold for articulations to enter a sleep state

Search for Articulations and Sleeping in PhysX docs for more details

Parameters
  • thresholds (Union[np.ndarray, torch.Tensor, wp.array]) – sleep thresholds to be applied. shape (M,).

  • indices (Optional[Union[np.ndarray, List, torch.Tensor, wp.array]], optional) – indices to specify which prims to manipulate. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

Example:

>>> # set the sleep threshold for all envs
>>> prims.set_sleep_thresholds(np.full((num_envs,), 0.01))
>>>
>>> # set only the sleep threshold for the first, middle and last of the 5 envs
>>> prims.set_sleep_thresholds(np.full((3,), 0.01), indices=np.array([0, 2, 4]))
set_solver_position_iteration_counts(counts: Union[numpy.ndarray, torch.Tensor, warp.types.array], indices: Optional[Union[numpy.ndarray, List, torch.Tensor, warp.types.array]] = None) None

Set the solver (position) iteration count for the articulations

The solver iteration count determines how accurately contacts, drives, and limits are resolved. Search for Solver Iteration Count in PhysX docs for more details.

Warning

Setting a higher number of iterations may improve the fidelity of the simulation, although it may affect its performance.

Parameters
  • counts (Union[np.ndarray, torch.Tensor, wp.array]) – number of iterations for the solver. Shape (M,).

  • indices (Optional[Union[np.ndarray, List, torch.Tensor, wp.array]], optional) – indices to specify which prims to manipulate. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

Example:

>>> # set the position iteration count for all envs
>>> prims.set_solver_position_iteration_counts(np.full((num_envs,), 64))
>>>
>>> # set only the position iteration count for the first, middle and last of the 5 envs
>>> prims.set_solver_position_iteration_counts(np.full((3,), 64), indices=np.array([0, 2, 4]))
set_solver_velocity_iteration_counts(counts: Union[numpy.ndarray, torch.Tensor, warp.types.array], indices: Optional[Union[numpy.ndarray, List, torch.Tensor, warp.types.array]] = None) None

Set the solver (velocity) iteration count for the articulations

The solver iteration count determines how accurately contacts, drives, and limits are resolved. Search for Solver Iteration Count in PhysX docs for more details.

Warning

Setting a higher number of iterations may improve the fidelity of the simulation, although it may affect its performance.

Parameters
  • counts (Union[np.ndarray, torch.Tensor, wp.array]) – number of iterations for the solver. Shape (M,).

  • indices (Optional[Union[np.ndarray, List, torch.Tensor, wp.array]], optional) – indices to specify which prims to manipulate. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

Example:

>>> # set the velocity iteration count for all envs
>>> prims.set_solver_velocity_iteration_counts(np.full((num_envs,), 64))
>>>
>>> # set only the velocity iteration count for the first, middle and last of the 5 envs
>>> prims.set_solver_velocity_iteration_counts(np.full((3,), 64), indices=np.array([0, 2, 4]))
set_stabilization_thresholds(thresholds: Union[numpy.ndarray, torch.Tensor, warp.types.array], indices: Optional[Union[numpy.ndarray, List, torch.Tensor, warp.types.array]] = None) None

Set the mass-normalized kinetic energy below which the articulation may participate in stabilization

Search for Stabilization Threshold in PhysX docs for more details

Parameters
  • thresholds (Union[np.ndarray, torch.Tensor, wp.array]) – stabilization thresholds to be applied. Shape (M,).

  • indices (Optional[Union[np.ndarray, List, torch.Tensor, wp.array]], optional) – indices to specify which prims to manipulate. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

Example:

>>> # set the stabilization threshold for all envs
>>> prims.set_stabilization_thresholds(np.full((num_envs,), 0.005))
>>>
>>> # set only the stabilization threshold for the first, middle and last of the 5 envs
>>> prims.set_stabilization_thresholds(np.full((3,), 0.0051), indices=np.array([0, 2, 4]))
set_velocities(velocities: Optional[Union[numpy.ndarray, torch.Tensor, warp.types.array]] = None, indices: Optional[Union[numpy.ndarray, list, torch.Tensor, warp.types.array]] = None) None

Set the linear and angular velocities of the prims in the view at once.

The method does this through the PhysX API only. It has to be called after initialization

Warning

This method will immediately set the articulation state

Parameters
  • velocities (Optional[Union[np.ndarray, torch.Tensor, wp.array]]) – linear and angular velocities respectively to set the rigid prims to. shape is (M, 6).

  • indices (Optional[Union[np.ndarray, list, torch.Tensor, wp.array]], optional) – indices to specify which prims to manipulate. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

Hint

This method belongs to the methods used to set the articulation kinematic state:

set_velocities (set_linear_velocities, set_angular_velocities), set_joint_positions, set_joint_velocities, set_joint_efforts

Example:

>>> # set each articulation linear velocity to (1., 1., 1.) and angular velocity to (.1, .1, .1)
>>> velocities = np.ones((num_envs, 6))
>>> velocities[:,3:] = 0.1
>>> prims.set_velocities(velocities)
>>>
>>> # set only the articulation velocities for the first, middle and last of the 5 envs
>>> velocities = np.ones((3, 6))
>>> velocities[:,3:] = 0.1
>>> prims.set_velocities(velocities, indices=np.array([0, 2, 4]))
set_visibilities(visibilities: Union[numpy.ndarray, torch.Tensor, warp.types.array], indices: Optional[Union[numpy.ndarray, list, torch.Tensor, warp.types.array]] = None) None

Set the visibilities of the prims in stage

Parameters
  • visibilities (Union[np.ndarray, torch.Tensor, wp.array]) – flag to set the visibilities of the usd prims in stage. Shape (M,). Where M <= size of the encapsulated prims in the view.

  • indices (Optional[Union[np.ndarray, list, torch.Tensor, wp.array]], optional) – indices to specify which prims to manipulate. Shape (M,). Defaults to None (i.e: all prims in the view).

Example:

>>> # make all prims not visible in the stage
>>> prims.set_visibilities(visibilities=[False] * num_envs)
set_world_poses(positions: Optional[Union[numpy.ndarray, torch.Tensor, warp.types.array]] = None, orientations: Optional[Union[numpy.ndarray, torch.Tensor, warp.types.array]] = None, indices: Optional[Union[numpy.ndarray, list, torch.Tensor, warp.types.array]] = None) None

Set poses of prims in the view with respect to the world’s frame.

Warning

This method will change (teleport) the prim poses immediately to the indicated value

Parameters
  • positions (Optional[Union[np.ndarray, torch.Tensor, wp.array]], optional) – positions in the world frame of the prim. shape is (M, 3). Defaults to None, which means left unchanged.

  • orientations (Optional[Union[np.ndarray, torch.Tensor, wp.array]], optional) – quaternion orientations in the world frame of the prims. quaternion is scalar-first (w, x, y, z). shape is (M, 4). Defaults to None, which means left unchanged.

  • indices (Optional[Union[np.ndarray, list, torch.Tensor, wp.array]], optional) – indices to specify which prims to manipulate. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

Hint

This method belongs to the methods used to set the prim state

Example:

>>> # reposition all articulations in row (x-axis)
>>> positions = np.zeros((num_envs, 3))
>>> positions[:,0] = np.arange(num_envs)
>>> orientations = np.tile(np.array([1.0, 0.0, 0.0, 0.0]), (num_envs, 1))
>>> prims.set_world_poses(positions, orientations)
>>>
>>> # reposition only the articulations for the first, middle and last of the 5 envs in column (y-axis)
>>> positions = np.zeros((3, 3))
>>> positions[:,1] = np.arange(3)
>>> orientations = np.tile(np.array([1.0, 0.0, 0.0, 0.0]), (3, 1))
>>> prims.set_world_poses(positions, orientations, indices=np.array([0, 2, 4]))
switch_control_mode(mode: str, indices: Optional[Union[numpy.ndarray, List, torch.Tensor, warp.types.array]] = None, joint_indices: Optional[Union[numpy.ndarray, List, torch.Tensor, warp.types.array]] = None) None

Switch control mode between "position", "velocity", or "effort" for all joints

This method will set the implicit Proportional-Derivative (PD) controller’s Kps (stiffnesses) and Kds (dampings), defined via the set_gains method, of the selected articulations and joints according to the following rule:

Control mode

Stiffnesses

Dampings

"position"

Kps

Kds

"velocity"

0

Kds

"effort"

0

0

Parameters
  • mode (str) – control mode to switch the articulations specified to. It can be "position", "velocity", or "effort"

  • indices (Optional[Union[np.ndarray, List, torch.Tensor, wp.array]], optional) – indices to specify which prims to manipulate. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

  • joint_indices (Optional[Union[np.ndarray, List, torch.Tensor, wp.array]], optional) – joint indices to specify which joints to manipulate. Shape (K,). Where K <= num of dofs. Defaults to None (i.e: all dofs).

Example:

>>> # set 'velocity' as control mode for all joints
>>> prims.switch_control_mode("velocity")
>>>
>>> # set 'effort' as control mode only for the fingers: panda_finger_joint1 (7) and panda_finger_joint2 (8)
>>> # for the first, middle and last of the 5 envs
>>> prims.switch_control_mode("effort", indices=np.array([0, 2, 4]), joint_indices=np.array([7, 8]))
switch_dof_control_mode(mode: str, dof_index: int, indices: Optional[Union[numpy.ndarray, List, torch.Tensor, warp.types.array]] = None) None

Switch control mode between "position", "velocity", or "effort" for the specified DOF

This method will set the implicit Proportional-Derivative (PD) controller’s Kps (stiffnesses) and Kds (dampings), defined via the set_gains method, of the selected DOF according to the following rule:

Control mode

Stiffnesses

Dampings

"position"

Kps

Kds

"velocity"

0

Kds

"effort"

0

0

Parameters
  • mode (str) – control mode to switch the DOF specified to. It can be "position", "velocity" or "effort"

  • dof_index (int) – dof index to switch the control mode of.

  • indices (Optional[Union[np.ndarray, List, torch.Tensor, wp.array]], optional) – indices to specify which prims to manipulate. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

Example:

>>> # set 'velocity' as control mode for the panda_joint1 (0) joint for all envs
>>> prims.switch_dof_control_mode("velocity", dof_index=0)
>>>
>>> # set 'effort' as control mode for the panda_joint1 (0) for the first, middle and last of the 5 envs
>>> prims.switch_dof_control_mode("effort", dof_index=0, indices=np.array([0, 2, 4]))

Scenes

class Scene

This class provides functions to add objects of interest in the stage to retrieve their information and set their reset default state in an easy way. For example: - performing certain commands post_reset - getting bounding boxes of the objects - Deleting the objects/ removing them from stage..etc.

Checkout the required tutorials at https://docs.omniverse.nvidia.com/app_isaacsim/app_isaacsim/overview.html

add(obj: omni.isaac.core.prims.xform_prim.XFormPrim) omni.isaac.core.prims.xform_prim.XFormPrim

[summary]

Parameters

obj (XFormPrim) – [description]

Raises
  • Exception – [description]

  • Exception – [description]

Returns

[description]

Return type

XFormPrim

add_default_ground_plane(z_position: float = 0, name='default_ground_plane', prim_path: str = '/World/defaultGroundPlane', static_friction: float = 0.5, dynamic_friction: float = 0.5, restitution: float = 0.8) None

[summary]

Parameters
  • z_position (float, optional) – [description]. Defaults to 0.

  • name (str, optional) – [description]. Defaults to “default_ground_plane”.

  • prim_path (str, optional) – [description]. Defaults to “/World/defaultGroundPlane”.

  • static_friction (float, optional) – [description]. Defaults to 0.5.

  • dynamic_friction (float, optional) – [description]. Defaults to 0.5.

  • restitution (float, optional) – [description]. Defaults to 0.8.

Returns

[description]

Return type

[type]

add_ground_plane(size: Optional[float] = None, z_position: float = 0, name='ground_plane', prim_path: str = '/World/groundPlane', static_friction: float = 0.5, dynamic_friction: float = 0.5, restitution: float = 0.8, color: Optional[numpy.ndarray] = None) None

[summary]

Parameters
  • size (Optional[float], optional) – [description]. Defaults to None.

  • z_position (float, optional) – [description]. Defaults to 0.

  • name (str, optional) – [description]. Defaults to “ground_plane”.

  • prim_path (str, optional) – [description]. Defaults to “/World/groundPlane”.

  • static_friction (float, optional) – [description]. Defaults to 0.5.

  • dynamic_friction (float, optional) – [description]. Defaults to 0.5.

  • restitution (float, optional) – [description]. Defaults to 0.8.

  • color (Optional[np.ndarray], optional) – [description]. Defaults to None.

Returns

[description]

Return type

[type]

clear(registry_only: bool = False) None

Clears the stage from all added objects to the Scene.

Parameters

registry_only (bool, optional) – True to remove the object from the scene registry only and not the USD. Defaults to False.

compute_object_AABB(name: str) Tuple[numpy.ndarray, numpy.ndarray]

[summary]

Parameters

name (str) – [description]

Raises

Exception – [description]

Returns

[description]

Return type

Tuple[np.ndarray, np.ndarray]

disable_bounding_boxes_computations() None

[summary]

enable_bounding_boxes_computations() None

[summary]

get_object(name: str) omni.isaac.core.prims.xform_prim.XFormPrim

[summary]

Parameters
  • name (Optional[str], optional) – [description]. Defaults to None.

  • prim_path (Optional[str], optional) – [description]. Defaults to None.

Returns

[description]

Return type

XFormPrim

object_exists(name: str) bool

[summary]

Parameters

name (str) – [description]

Returns

[description]

Return type

XFormPrim

post_reset() None

calls post_reset on all added objects to the Scene Registry.

remove_object(name: str, registry_only: bool = False) None

[summary]

Parameters
  • name (str) – Name of the prim to be removed. Defaults to None.

  • registry_only (bool, optional) – True to remove the object from the scene registry only and not the USD. Defaults to False.

property stage: pxr.Usd.Stage

[summary]

Returns

[description]

Return type

Usd.Stage

class SceneRegistry
add_articulated_system(name, articulated_system: omni.isaac.core.articulations.articulation.Articulation) None

[summary]

Parameters
  • name ([type]) – [description]

  • articulated_system (Articulation) – [description]

add_articulated_view(name, articulated_view: omni.isaac.core.articulations.articulation_view.ArticulationView) None

[summary]

Parameters
  • name ([type]) – [description]

  • articulated_view (ArticulationView) – [description]

add_cloth(name, cloth: omni.isaac.core.prims.soft.cloth_prim.ClothPrim) None

[summary]

Parameters
  • name ([type]) – [description]

  • cloth (ClothPrim) – [description]

add_cloth_view(name, cloth_prim_view: omni.isaac.core.prims.soft.cloth_prim_view.ClothPrimView) None

[summary]

Parameters
  • name ([type]) – [description]

  • geometry_object (ClothPrimView) – [description]

add_deformable(name, deformable: omni.isaac.core.prims.soft.deformable_prim.DeformablePrim) None

[summary]

Parameters
  • name ([type]) – [description]

  • deformable (DeformablePrim) – [description]

add_deformable_material(name, deformable_material: omni.isaac.core.materials.deformable_material.DeformableMaterial) None

[summary]

Parameters
add_deformable_material_view(name, deformable_material_view: omni.isaac.core.materials.deformable_material_view.DeformableMaterialView) None

[summary]

Parameters
add_deformable_view(name, deformable_prim_view: omni.isaac.core.prims.soft.deformable_prim_view.DeformablePrimView) None

[summary]

Parameters
  • name ([type]) – [description]

  • geometry_object (DeformablePrimView) – [description]

add_geometry_object(name, geometry_object: omni.isaac.core.prims.geometry_prim.GeometryPrim) None

[summary]

Parameters
  • name ([type]) – [description]

  • geometry_object (GeometryPrim) – [description]

add_geometry_prim_view(name, geometry_prim_view: omni.isaac.core.prims.geometry_prim_view.GeometryPrimView) None

[summary]

Parameters
  • name ([type]) – [description]

  • geometry_object (GeometryPrim) – [description]

add_particle_material(name, particle_material: omni.isaac.core.materials.particle_material.ParticleMaterial) None

[summary]

Parameters
  • name ([type]) – [description]

  • geometry_object (ParticleMaterial) – [description]

add_particle_material_view(name, particle_material_view: omni.isaac.core.materials.particle_material_view.ParticleMaterialView) None

[summary]

Parameters
add_particle_system(name, particle_system: omni.isaac.core.prims.soft.particle_system.ParticleSystem) None

[summary]

Parameters
add_particle_system_view(name, particle_system_view: omni.isaac.core.prims.soft.particle_system_view.ParticleSystemView) None

[summary]

Parameters
add_rigid_contact_view(name, rigid_contact_view: omni.isaac.core.prims.rigid_contact_view.RigidContactView) None

[summary]

Parameters
  • name ([type]) – [description]

  • rigid_contact_views (RigidContactView) – [description]

add_rigid_object(name, rigid_object: omni.isaac.core.prims.rigid_prim.RigidPrim) None

[summary]

Parameters
  • name ([type]) – [description]

  • rigid_object (RigidPrim) – [description]

add_rigid_prim_view(name, rigid_prim_view: omni.isaac.core.prims.rigid_prim_view.RigidPrimView) None

[summary]

Parameters
  • name ([type]) – [description]

  • rigid_object (RigidPrim) – [description]

add_robot(name, robot: omni.isaac.core.robots.robot.Robot) None

[summary]

Parameters
  • name ([type]) – [description]

  • robot (Robot) – [description]

add_robot_view(name, robot_view: omni.isaac.core.robots.robot_view.RobotView) None

[summary]

Parameters
  • name ([type]) – [description]

  • geometry_object (GeometryPrim) – [description]

add_sensor(name, sensor: omni.isaac.core.prims.base_sensor.BaseSensor) None

[summary]

Parameters

name ([type]) – [description] sensor (BaseSensor): [description]

add_xform(name, xform: omni.isaac.core.prims.xform_prim.XFormPrim) None

[summary]

Parameters
  • name ([type]) – [description]

  • robot (Robot) – [description]

add_xform_view(name, xform_prim_view: omni.isaac.core.prims.xform_prim_view.XFormPrimView) None

[summary]

Parameters
  • name ([type]) – [description]

  • geometry_object (GeometryPrim) – [description]

property articulated_systems: dict

[summary]

Returns

[description]

Return type

dict

property articulated_views: dict

[summary]

Returns

[description]

Return type

dict

property cloth_prim_views: dict

[summary]

Returns

[description]

Return type

dict

property cloth_prims: dict

[summary]

Returns

[description]

Return type

dict

property deformable_material_views: dict

[summary]

Returns

[description]

Return type

dict

property deformable_materials: dict

[summary]

Returns

[description]

Return type

dict

property deformable_prim_views: dict

[summary]

Returns

[description]

Return type

dict

property deformable_prims: dict

[summary]

Returns

[description]

Return type

dict

property geometry_prim_views: dict

[summary]

Returns

[description]

Return type

dict

get_object(name: str) omni.isaac.core.prims.xform_prim.XFormPrim

[summary]

Parameters
  • name (Optional[str], optional) – [description]. Defaults to None.

  • prim_path (Optional[str], optional) – [description]. Defaults to None.

Raises

Exception – [description]

Returns

[description]

Return type

XFormPrim

name_exists(name: str) bool

[summary]

Parameters

name (str) – [description]

Returns

[description]

Return type

bool

property particle_material_views: dict

[summary]

Returns

[description]

Return type

dict

property particle_materials: dict

[summary]

Returns

[description]

Return type

dict

property particle_system_views: dict

[summary]

Returns

[description]

Return type

dict

property particle_systems: dict

[summary]

Returns

[description]

Return type

dict

remove_object(name: str) None

[summary]

Parameters
  • name (Optional[str], optional) – [description]. Defaults to None.

  • prim_path (Optional[str], optional) – [description]. Defaults to None.

Raises
  • Exception – [description]

  • Exception – [description]

  • NotImplementedError – [description]

  • Exception – [description]

property rigid_contact_views: dict

[summary]

Returns

[description]

Return type

dict

property rigid_objects: dict

[summary]

Returns

[description]

Return type

dict

property rigid_prim_views: dict

[summary]

Returns

[description]

Return type

dict

property robot_views: dict

[summary]

Returns

[description]

Return type

dict

property robots: dict

[summary]

Returns

[description]

Return type

dict

property sensors: dict

[summary]

Returns

[description]

Return type

dict

property xform_prim_views: dict

[summary]

Returns

[description]

Return type

dict

property xforms: dict

[summary]

Returns

[description]

Return type

dict


Simulation Context

class SimulationContext(*args, **kwargs)

This class provide functions that take care of many time-related events such as perform a physics or a render step for instance. Adding/ removing callback functions that gets triggered with certain events such as a physics step, timeline event (pause or play..etc), stage open/ close..etc.

It also includes an instance of PhysicsContext which takes care of many physics related settings such as setting physics dt, solver type..etc.

Parameters
  • physics_dt (Optional[float], optional) – dt between physics steps. Defaults to None.

  • rendering_dt (Optional[float], optional) – dt between rendering steps. Note: rendering means rendering a frame of the current application and not only rendering a frame to the viewports/cameras. So UI elements of Isaac Sim will be refreshed with this dt as well if running non-headless. Defaults to None.

  • stage_units_in_meters (Optional[float], optional) – The metric units of assets. This will affect gravity value..etc. Defaults to None.

  • physics_prim_path (Optional[str], optional) – specifies the prim path to create a PhysicsScene at, only in the case where no PhysicsScene already defined. Defaults to “/physicsScene”.

  • set_defaults (bool, optional) – set to True to use the defaults settings [physics_dt = 1.0/ 60.0, stage units in meters = 0.01 (i.e in cms), rendering_dt = 1.0 / 60.0, gravity = -9.81 m / s ccd_enabled, stabilization_enabled, gpu dynamics turned off, broadcast type is MBP, solver type is TGS]. Defaults to True.

  • backend (str, optional) – specifies the backend to be used (numpy or torch or warp). Defaults to numpy.

  • device (Optional[str], optional) – specifies the device to be used if running on the gpu with torch or warp backend.

Example:

>>> from omni.isaac.core import SimulationContext
>>>
>>> simulation_context = SimulationContext()
>>> simulation_context
<omni.isaac.core.simulation_context.simulation_context.SimulationContext object at 0x...>
add_physics_callback(callback_name: str, callback_fn: Callable[[float], None]) None

Add a callback which will be called before each physics step.

callback_fn should take a float argument (e.g., step_size)

Parameters
  • callback_name (str) – should be unique.

  • callback_fn (Callable[[float], None]) – [description]

Example:

>>> def callback_physics(step_size):
...     print("physics callback -> step_size:", step_size)
...
>>> simulation_context.add_physics_callback("callback_physics", callback_physics)
add_render_callback(callback_name: str, callback_fn: Callable) None

Add a callback which will be called after each rendering event such as .render().

callback_fn should take an argument of type (e.g., event)

Parameters
  • callback_name (str) – [description]

  • callback_fn (Callable) – [description]

Example:

>>> def callback_render(event):
...     print("render callback -> event:", event)
...
>>> simulation_context.add_render_callback("callback_render", callback_render)
add_stage_callback(callback_name: str, callback_fn: Callable) None

Add a callback which will be called after each stage event such as open/close among others

callback_fn should take an argument of type omni.usd.StageEvent (e.g., event)

Parameters
  • callback_name (str) – [description]

  • callback_fn (Callable[[omni.usd.StageEvent], None]) – [description]

Example:

>>> def callback_stage(event):
...     print("stage callback -> event:", event)
...
>>> simulation_context.add_stage_callback("callback_stage", callback_stage)
add_timeline_callback(callback_name: str, callback_fn: Callable) None

Add a callback which will be called after each timeline event such as play/pause.

callback_fn should take an argument of type omni.timeline.TimelineEvent (e.g., event)

Parameters
  • callback_name (str) – [description]

  • callback_fn (Callable[[omni.timeline.TimelineEvent], None]) – [description]

Example:

>>> def callback_timeline(event):
...     print("timeline callback -> event:", event)
...
>>> simulation_context.add_timeline_callback("callback_timeline", callback_timeline)
property app: omni.kit.app._app.IApp
Returns

Omniverse Kit Application interface

Return type

omni.kit.app.IApp

Example:

>>> simulation_context.app
<omni.kit.app._app.IApp object at 0x...>
property backend: str
Returns

current backend. Supported backends are: "numpy", "torch" and "warp"

Return type

str

Example:

>>> simulation_context.backend
numpy
property backend_utils

Get the current backend utils module

Backend

Utils module

"numpy"

omni.isaac.core.utils.numpy

"torch"

omni.isaac.core.utils.torch

"warp"

omni.isaac.core.utils.warp

Returns

current backend utils module

Return type

str

Example:

>>> simulation_context.backend_utils
<module 'omni.isaac.core.utils.numpy'>
clear() None

Clear the current stage leaving the PhysicsScene and /World

Example:

>>> simulation_context.clear()
clear_all_callbacks() None

Clear all callbacks which were added using any add_*_callback method

Example:

>>> simulation_context.clear_render_callbacks()
classmethod clear_instance() None

Delete the simulation context object, if it was instantiated before, and destroy any subscribed callback

Example:

>>> SimulationContext.clear_instance()
clear_physics_callbacks() None

Remove all registered physics callbacks

Example:

>>> simulation_context.clear_physics_callbacks()
clear_render_callbacks() None

Remove all registered render callbacks

Example:

>>> simulation_context.clear_render_callbacks()
clear_stage_callbacks() None

Remove all registered stage callbacks

Example:

>>> simulation_context.clear_stage_callbacks()
clear_timeline_callbacks() None

Remove all registered timeline callbacks

Example:

>>> simulation_context.clear_timeline_callbacks()
property current_time: float
Returns

current time (simulated physical time) that have elapsed since the simulation was played

Return type

float

Example:

>>> # given a running Isaac Sim instance and after 911 physics steps at 60 Hz
>>> simulation_context.current_time
15.183334125205874
property current_time_step_index: int
Returns

current number of physics steps that have elapsed since the simulation was played

Return type

int

Example:

>>> # given a running Isaac Sim instance and after approximately 15 seconds of physics simulation at 60 Hz
>>> simulation_context.current_time_step_index
911
property device: str
Returns

Device used by the physics context. None for numpy backend

Return type

str

Example:

>>> simulation_context.device
None
get_block_on_render() bool

Get the block on render flag for the simulation thread

Returns

True if one frame lag between any data captured from the render products and the current USD stage is guaranteed by blocking the step call.

Return type

bool

Example:

>>> simulation_context.get_block_on_render()
False
get_physics_context() omni.isaac.core.physics_context.physics_context.PhysicsContext

Get the physics context (a class to deal with a physics scene and its settings) instance

Raises

Exception – if there is no stage currently opened

Returns

physics context object

Return type

PhysicsContext

Example:

>>> simulation_context.get_physics_context()
<omni.isaac.core.physics_context.physics_context.PhysicsContext object at 0x...>
get_physics_dt() float

Get the current physics dt of the physics context

Raises

Exception – if there is no stage currently opened

Returns

current physics dt of the PhysicsContext

Return type

float

Example:

>>> simulation_context.get_physics_dt()
0.016666666666666666
get_rendering_dt() float

Get the current rendering dt

Raises

Exception – if there is no stage currently opened

Returns

current rendering dt

Return type

float

Example:

>>> simulation_context.get_rendering_dt()
0.016666666666666666
initialize_physics() None

Initialize the physics simulation view

Example:

>>> simulation_context.initialize_physics()
async initialize_simulation_context_async() None

Initialize the simulation context

Hint

This method is intended to be used in the Isaac Sim’s Extensions workflow where the Kit application has the control over timing of physics and rendering steps

Example:

>>> from omni.kit.async_engine import run_coroutine
>>>
>>> async def task():
...     await simulation_context.initialize_simulation_context_async()
...
>>> run_coroutine(task())
classmethod instance() omni.isaac.core.simulation_context.simulation_context.SimulationContext

Get the instance of the class, if it was instantiated before

Returns

SimulationContext object or None

Return type

SimulationContext

Example:

>>> # given that the class has already been instantiated before
>>> simulation_context = SimulationContext.instance()
>>> simulation_context
<omni.isaac.core.simulation_context.simulation_context.SimulationContext object at 0x...>
is_playing() bool

Check whether the simulation is playing

Returns

True if the simulator is playing.

Return type

bool

Example:

>>> # given a simulation in play
>>> simulation_context.is_playing()
True
is_simulating() bool

Check whether the simulation is running or not

Warning

With deprecation of Dynamic Control Toolbox, this function is not needed

It can return True if start_simulation is called even if play was pressed/called.

Returns

bool” True if physics simulation is happening.

Example:

>>> # given a running simulation
>>> simulation_context.is_simulating()
True
is_stopped() bool

Check whether the simulation is playing

Returns

True if the simulator is stopped.

Return type

bool

Example:

>>> # given a simulation in play
>>> simulation_context.is_stopped()
False
pause() None

Pause the physics simulation

Example:

>>> simulation_context.pause()
async pause_async() None

Pause the physics simulation

Example:

>>> from omni.kit.async_engine import run_coroutine
>>>
>>> async def task():
...     await simulation_context.pause_async()
...
>>> run_coroutine(task())
physics_callback_exists(callback_name: str) bool

Check if a physics callback exists

Parameters

callback_name (str) – callback name

Returns

whether the callback is registered

Return type

bool

Example:

>>> # given a registered callback named 'callback_physics'
>>> simulation_context.physics_callback_exists("callback_physics")
True
property physics_sim_view

Note

The physics simulation view instance will be only available after initializing the physics (see initialize_physics) or resetting the simulation context (see reset)

Returns

Physics simulation view instance

Return type

PhysicsContext

Example:

>>> simulation_context.physics_sim_view
<omni.physics.tensors.impl.api.SimulationView object at 0x...>
play() None

Start playing simulation

Note

It does one step internally to propagate all physics handles properly.

Example:

>>> simulation_context.play()
async play_async() None

Start playing simulation

Example:

>>> from omni.kit.async_engine import run_coroutine
>>>
>>> async def task():
...     await simulation_context.play_async()
...
>>> run_coroutine(task())
remove_physics_callback(callback_name: str) None

Remove a physics callback by its name

Parameters

callback_name (str) – callback name

Example:

>>> # given a registered callback named 'callback_physics'
>>> simulation_context.remove_physics_callback("callback_physics")
remove_render_callback(callback_name: str) None

Remove a render callback by its name

Parameters

callback_name (str) – callback name

Example:

>>> # given a registered callback named 'callback_render'
>>> simulation_context.remove_render_callback("callback_render")
remove_stage_callback(callback_name: str) None

Remove a stage callback by its name

Parameters

callback_name (str) – callback name

Example:

>>> # given a registered callback named 'callback_stage'
>>> simulation_context.remove_stage_callback("callback_stage")
remove_timeline_callback(callback_name: str) None

Remove a timeline callback by its name

Parameters

callback_name (str) – callback name

Example:

>>> # given a registered callback named 'timeline'
>>> simulation_context.timeline_callback("timeline")
render() None

Refresh the Isaac Sim app rendering components including UI elements, viewports and others

Warning

This method is not intended to be used in the Isaac Sim’s Extensions workflow since the Kit application has the control over the rendering steps

Example:

>>> simulation_context.render()
async render_async() None

Refresh the Isaac Sim app rendering components including UI elements, viewports and others

Hint

This method is intended to be used in the Isaac Sim’s Extensions workflow where the Kit application has the control over timing of physics and rendering steps

Example:

>>> from omni.kit.async_engine import run_coroutine
>>>
>>> async def task():
...     await simulation_context.render_async()
...
>>> run_coroutine(task())
render_callback_exists(callback_name: str) bool

Check if a render callback exists

Parameters

callback_name (str) – callback name

Returns

whether the callback is registered

Return type

bool

Example:

>>> # given a registered callback named 'callback_render'
>>> simulation_context.render_callback_exists("callback_render")
True
reset(soft: bool = False) None

Reset the physics simulation view.

Warning

This method is not intended to be used in the Isaac Sim’s Extensions workflow since the Kit application has the control over the rendering steps. For the Extensions workflow use the reset_async method instead

Parameters

soft (bool, optional) – if set to True simulation won’t be stopped and start again. It only calls the reset on the scene objects.

Example:

>>> simulation_context.reset()
async reset_async(soft: bool = False) None

Reset the physics simulation view (asynchronous version).

Parameters

soft (bool, optional) – if set to True simulation won’t be stopped and start again. It only calls the reset on the scene objects.

Example:

>>> from omni.kit.async_engine import run_coroutine
>>>
>>> async def task():
>>>     await simulation_context.reset_async()
>>>
>>> run_coroutine(task())
set_block_on_render(block: bool) None

Set block on render flag for the simulation thread

Note

This guarantee a one frame lag between any data captured from the render products and the current USD stage if enabled.

Parameters

block (bool) – True to block the thread until the renderer is done.

Example:

>>> simulation_context.set_block_on_render(False)
set_simulation_dt(physics_dt: Optional[float] = None, rendering_dt: Optional[float] = None) None

Specify the physics step and rendering step size to use when stepping and rendering.

Parameters
  • physics_dt (float) – The physics time-step. None means it won’t change the current setting. (default: None).

  • rendering_dt (float) – The rendering time-step. None means it won’t change the current setting. (default: None)

Hint

It is recommended that the two values be divisible, with the rendering_dt being equal to or greater than the physics_dt

Example:

>>> set physics dt to 120 Hz and rendering dt to 60Hz (2 physics steps for each rendering)
>>> simulation_context.set_simulation_dt(physics_dt=1.0 / 120.0, rendering_dt=1.0 / 60.0)
property stage: pxr.Usd.Stage
Returns

current open USD stage

Return type

Usd.Stage

Example:

>>> simulation_context.stage
Usd.Stage.Open(rootLayer=Sdf.Find('anon:0x...:World....usd'),
               sessionLayer=Sdf.Find('anon:0x...:World...-session.usda'),
               pathResolverContext=<invalid repr>)
stage_callback_exists(callback_name: str) bool

Check if a stage callback exists

Parameters

callback_name (str) – callback name

Returns

whether the callback is registered

Return type

bool

Example:

>>> # given a registered callback named 'callback_stage'
>>> simulation_context.stage_callback_exists("callback_stage")
True
step(render: bool = True) None

Steps the physics simulation while rendering or without.

Warning

Calling this method with the render parameter set to True (default value) is not intended to be used in the Isaac Sim’s Extensions workflow since the Kit application has the control over the rendering steps

Parameters

render (bool, optional) – Set to False to only do a physics simulation without rendering. Note: app UI will be frozen (since its not rendering) in this case. Defaults to True.

Raises

Exception – if there is no stage currently opened

Example:

>>> simulation_context.step()
stop() None

Stop the physics simulation

Example:

>>> simulation_context.stop()
async stop_async() None

Stop the physics simulation

Example:

>>> from omni.kit.async_engine import run_coroutine
>>>
>>> async def task():
...     await simulation_context.stop_async()
...
>>> run_coroutine(task())
timeline_callback_exists(callback_name: str) bool

Check if a timeline callback exists

Parameters

callback_name (str) – callback name

Returns

whether the callback is registered

Return type

bool

Example:

>>> # given a registered callback named 'callback_timeline'
>>> simulation_context.timeline_callback_exists("callback_timeline")
True

World

class World(*args, **kwargs)

This class inherits from SimulationContext which provides the following.

SimulationContext provide functions that take care of many time-related events such as perform a physics or a render step for instance. Adding/ removing callback functions that gets triggered with certain events such as a physics step, timeline event (pause or play..etc), stage open/ close..etc.

It also includes an instance of PhysicsContext which takes care of many physics related settings such as setting physics dt, solver type..etc.

In addition to what is provided from SimulationContext, this class allows the user to add a task to the world and it contains a scene object.

To control the default reset state of different objects easily, the object could be added to a Scene. Besides this, the object is bound to a short keyword that facilitates objects retrievals, like in a dict.

Checkout the required tutorials at https://docs.omniverse.nvidia.com/app_isaacsim/app_isaacsim/overview.html

Parameters
  • physics_dt (Optional[float], optional) – dt between physics steps. Defaults to None.

  • rendering_dt (Optional[float], optional) – dt between rendering steps. Note: rendering means rendering a frame of the current application and not only rendering a frame to the viewports/ cameras. So UI elements of Isaac Sim will be refreshed with this dt as well if running non-headless. Defaults to None.

  • stage_units_in_meters (Optional[float], optional) – The metric units of assets. This will affect gravity value..etc. Defaults to None.

  • physics_prim_path (Optional[str], optional) – specifies the prim path to create a PhysicsScene at, only in the case where no PhysicsScene already defined. Defaults to “/physicsScene”.

  • set_defaults (bool, optional) – set to True to use the defaults settings [physics_dt = 1.0/ 60.0, stage units in meters = 0.01 (i.e in cms), rendering_dt = 1.0 / 60.0, gravity = -9.81 m / s ccd_enabled, stabilization_enabled, gpu dynamics turned off, broadcast type is MBP, solver type is TGS]. Defaults to True.

  • backend (str, optional) – specifies the backend to be used (numpy or torch or warp). Defaults to numpy.

  • device (Optional[str], optional) – specifies the device to be used if running on the gpu with torch or warp backends.

Example:

>>> from omni.isaac.core import World
>>>
>>> world = World()
>>> world
<omni.isaac.core.world.world.World object at 0x...>
add_physics_callback(callback_name: str, callback_fn: Callable[[float], None]) None

Add a callback which will be called before each physics step.

callback_fn should take a float argument (e.g., step_size)

Parameters
  • callback_name (str) – should be unique.

  • callback_fn (Callable[[float], None]) – [description]

Example:

>>> def callback_physics(step_size):
...     print("physics callback -> step_size:", step_size)
...
>>> simulation_context.add_physics_callback("callback_physics", callback_physics)
add_render_callback(callback_name: str, callback_fn: Callable) None

Add a callback which will be called after each rendering event such as .render().

callback_fn should take an argument of type (e.g., event)

Parameters
  • callback_name (str) – [description]

  • callback_fn (Callable) – [description]

Example:

>>> def callback_render(event):
...     print("render callback -> event:", event)
...
>>> simulation_context.add_render_callback("callback_render", callback_render)
add_stage_callback(callback_name: str, callback_fn: Callable) None

Add a callback which will be called after each stage event such as open/close among others

callback_fn should take an argument of type omni.usd.StageEvent (e.g., event)

Parameters
  • callback_name (str) – [description]

  • callback_fn (Callable[[omni.usd.StageEvent], None]) – [description]

Example:

>>> def callback_stage(event):
...     print("stage callback -> event:", event)
...
>>> simulation_context.add_stage_callback("callback_stage", callback_stage)
add_task(task: omni.isaac.core.tasks.base_task.BaseTask) None

Add a task to the task registry

Note

Tasks should have a unique name

Parameters

task (BaseTask) – task object

Example:

>>> from omni.isaac.core.tasks import BaseTask
>>>
>>> class Task(BaseTask):
...    def get_observations(self):
...        return {'obs': [0]}
...
...    def calculate_metrics(self):
...        return {"reward": 1}
...
...    def is_done(self):
...        return False
...
>>> task = Task(name="custom_task")
>>> world.add_task(task)
add_timeline_callback(callback_name: str, callback_fn: Callable) None

Add a callback which will be called after each timeline event such as play/pause.

callback_fn should take an argument of type omni.timeline.TimelineEvent (e.g., event)

Parameters
  • callback_name (str) – [description]

  • callback_fn (Callable[[omni.timeline.TimelineEvent], None]) – [description]

Example:

>>> def callback_timeline(event):
...     print("timeline callback -> event:", event)
...
>>> simulation_context.add_timeline_callback("callback_timeline", callback_timeline)
property app: omni.kit.app._app.IApp
Returns

Omniverse Kit Application interface

Return type

omni.kit.app.IApp

Example:

>>> simulation_context.app
<omni.kit.app._app.IApp object at 0x...>
property backend: str
Returns

current backend. Supported backends are: "numpy", "torch" and "warp"

Return type

str

Example:

>>> simulation_context.backend
numpy
property backend_utils

Get the current backend utils module

Backend

Utils module

"numpy"

omni.isaac.core.utils.numpy

"torch"

omni.isaac.core.utils.torch

"warp"

omni.isaac.core.utils.warp

Returns

current backend utils module

Return type

str

Example:

>>> simulation_context.backend_utils
<module 'omni.isaac.core.utils.numpy'>
calculate_metrics(task_name: Optional[str] = None) None

Get metrics from all the tasks that were added

Parameters

task_name (Optional[str], optional) – task name to ask for. Defaults to None, which means all the tasks

Returns

the computed task (or all tasks) metric

Return type

dict

Example:

>>> world.calculate_metrics("custom_task")
{'reward': 1}
clear() None

Clear the current stage leaving the PhysicsScene and /World

Example:

>>> world.clear()
clear_all_callbacks() None

Clear all callbacks which were added using any add_*_callback method

Example:

>>> simulation_context.clear_render_callbacks()
classmethod clear_instance()

Delete the world object, if it was instantiated before, and destroy any subscribed callback

Example:

>>> World.clear_instance()
clear_physics_callbacks() None

Remove all registered physics callbacks

Example:

>>> simulation_context.clear_physics_callbacks()
clear_render_callbacks() None

Remove all registered render callbacks

Example:

>>> simulation_context.clear_render_callbacks()
clear_stage_callbacks() None

Remove all registered stage callbacks

Example:

>>> simulation_context.clear_stage_callbacks()
clear_timeline_callbacks() None

Remove all registered timeline callbacks

Example:

>>> simulation_context.clear_timeline_callbacks()
property current_time: float
Returns

current time (simulated physical time) that have elapsed since the simulation was played

Return type

float

Example:

>>> # given a running Isaac Sim instance and after 911 physics steps at 60 Hz
>>> simulation_context.current_time
15.183334125205874
property current_time_step_index: int
Returns

current number of physics steps that have elapsed since the simulation was played

Return type

int

Example:

>>> # given a running Isaac Sim instance and after approximately 15 seconds of physics simulation at 60 Hz
>>> simulation_context.current_time_step_index
911
property dc_interface: omni.isaac.dynamic_control._dynamic_control.DynamicControl
Returns

DynamicControl instance

Return type

_dynamic_control.DynamicControl

Example:

>>> world.dc_interface
<omni.isaac.dynamic_control._dynamic_control.DynamicControl object at 0x...>
property device: str
Returns

Device used by the physics context. None for numpy backend

Return type

str

Example:

>>> simulation_context.device
None
get_block_on_render() bool

Get the block on render flag for the simulation thread

Returns

True if one frame lag between any data captured from the render products and the current USD stage is guaranteed by blocking the step call.

Return type

bool

Example:

>>> simulation_context.get_block_on_render()
False
get_current_tasks() List[omni.isaac.core.tasks.base_task.BaseTask]

Get a dictionary of the registered tasks where keys are task names

Returns

registered tasks

Return type

List[BaseTask]

Example:

>>> world.get_current_tasks()
{'custom_task': <custom.task.scripts.extension.Task object at 0x...>}
get_data_logger() omni.isaac.core.loggers.data_logger.DataLogger

Return the data logger of the world.

Returns

data logger instance

Return type

DataLogger

Example:

>>> world.get_data_logger()
<omni.isaac.core.loggers.data_logger.DataLogger object at 0x...>
get_observations(task_name: Optional[str] = None) dict

Get observations from all the tasks that were added

Parameters

task_name (Optional[str], optional) – task name to ask for. Defaults to None, which means all the tasks

Returns

the task (or all tasks) observations

Return type

dict

Example:

>>> world.get_observations("custom_task")
{'obs': [0]}
get_physics_context() omni.isaac.core.physics_context.physics_context.PhysicsContext

Get the physics context (a class to deal with a physics scene and its settings) instance

Raises

Exception – if there is no stage currently opened

Returns

physics context object

Return type

PhysicsContext

Example:

>>> simulation_context.get_physics_context()
<omni.isaac.core.physics_context.physics_context.PhysicsContext object at 0x...>
get_physics_dt() float

Get the current physics dt of the physics context

Raises

Exception – if there is no stage currently opened

Returns

current physics dt of the PhysicsContext

Return type

float

Example:

>>> simulation_context.get_physics_dt()
0.016666666666666666
get_rendering_dt() float

Get the current rendering dt

Raises

Exception – if there is no stage currently opened

Returns

current rendering dt

Return type

float

Example:

>>> simulation_context.get_rendering_dt()
0.016666666666666666
get_task(name: str) omni.isaac.core.tasks.base_task.BaseTask

Get a task by its name

Example:

>>> world.get_task("custom_task")
<custom.task.scripts.extension.Task object at 0x...>
initialize_physics() None

Initialize the physics simulation view and each added object to the Scene

Example:

>>> world.initialize_physics()
async initialize_simulation_context_async() None

Initialize the simulation context

Hint

This method is intended to be used in the Isaac Sim’s Extensions workflow where the Kit application has the control over timing of physics and rendering steps

Example:

>>> from omni.kit.async_engine import run_coroutine
>>>
>>> async def task():
...     await simulation_context.initialize_simulation_context_async()
...
>>> run_coroutine(task())
classmethod instance() omni.isaac.core.simulation_context.simulation_context.SimulationContext

Get the instance of the class, if it was instantiated before

Returns

SimulationContext object or None

Return type

SimulationContext

Example:

>>> # given that the class has already been instantiated before
>>> simulation_context = SimulationContext.instance()
>>> simulation_context
<omni.isaac.core.simulation_context.simulation_context.SimulationContext object at 0x...>
is_done(task_name: Optional[str] = None) bool

Get done from all the tasks that were added

Parameters

task_name (Optional[str], optional) – task name to ask for. Defaults to None, which means all the tasks

Returns

whether the task (or all tasks) is done

Return type

bool

Example:

>>> world.is_done("custom_task")
False
is_playing() bool

Check whether the simulation is playing

Returns

True if the simulator is playing.

Return type

bool

Example:

>>> # given a simulation in play
>>> simulation_context.is_playing()
True
is_simulating() bool

Check whether the simulation is running or not

Warning

With deprecation of Dynamic Control Toolbox, this function is not needed

It can return True if start_simulation is called even if play was pressed/called.

Returns

bool” True if physics simulation is happening.

Example:

>>> # given a running simulation
>>> simulation_context.is_simulating()
True
is_stopped() bool

Check whether the simulation is playing

Returns

True if the simulator is stopped.

Return type

bool

Example:

>>> # given a simulation in play
>>> simulation_context.is_stopped()
False
is_tasks_scene_built() bool

Check if the set_up_scene method was called for each registered task

Example:

>>> # given a world instance that was rested at some point
>>> world.is_tasks_scene_built()
True
pause() None

Pause the physics simulation

Example:

>>> simulation_context.pause()
async pause_async() None

Pause the physics simulation

Example:

>>> from omni.kit.async_engine import run_coroutine
>>>
>>> async def task():
...     await simulation_context.pause_async()
...
>>> run_coroutine(task())
physics_callback_exists(callback_name: str) bool

Check if a physics callback exists

Parameters

callback_name (str) – callback name

Returns

whether the callback is registered

Return type

bool

Example:

>>> # given a registered callback named 'callback_physics'
>>> simulation_context.physics_callback_exists("callback_physics")
True
property physics_sim_view

Note

The physics simulation view instance will be only available after initializing the physics (see initialize_physics) or resetting the simulation context (see reset)

Returns

Physics simulation view instance

Return type

PhysicsContext

Example:

>>> simulation_context.physics_sim_view
<omni.physics.tensors.impl.api.SimulationView object at 0x...>
play() None

Start playing simulation

Note

It does one step internally to propagate all physics handles properly.

Example:

>>> simulation_context.play()
async play_async() None

Start playing simulation

Example:

>>> from omni.kit.async_engine import run_coroutine
>>>
>>> async def task():
...     await simulation_context.play_async()
...
>>> run_coroutine(task())
remove_physics_callback(callback_name: str) None

Remove a physics callback by its name

Parameters

callback_name (str) – callback name

Example:

>>> # given a registered callback named 'callback_physics'
>>> simulation_context.remove_physics_callback("callback_physics")
remove_render_callback(callback_name: str) None

Remove a render callback by its name

Parameters

callback_name (str) – callback name

Example:

>>> # given a registered callback named 'callback_render'
>>> simulation_context.remove_render_callback("callback_render")
remove_stage_callback(callback_name: str) None

Remove a stage callback by its name

Parameters

callback_name (str) – callback name

Example:

>>> # given a registered callback named 'callback_stage'
>>> simulation_context.remove_stage_callback("callback_stage")
remove_timeline_callback(callback_name: str) None

Remove a timeline callback by its name

Parameters

callback_name (str) – callback name

Example:

>>> # given a registered callback named 'timeline'
>>> simulation_context.timeline_callback("timeline")
render() None

Refresh the Isaac Sim app rendering components including UI elements, viewports and others

Warning

This method is not intended to be used in the Isaac Sim’s Extensions workflow since the Kit application has the control over the rendering steps

Example:

>>> simulation_context.render()
async render_async() None

Refresh the Isaac Sim app rendering components including UI elements, viewports and others

Hint

This method is intended to be used in the Isaac Sim’s Extensions workflow where the Kit application has the control over timing of physics and rendering steps

Example:

>>> from omni.kit.async_engine import run_coroutine
>>>
>>> async def task():
...     await simulation_context.render_async()
...
>>> run_coroutine(task())
render_callback_exists(callback_name: str) bool

Check if a render callback exists

Parameters

callback_name (str) – callback name

Returns

whether the callback is registered

Return type

bool

Example:

>>> # given a registered callback named 'callback_render'
>>> simulation_context.render_callback_exists("callback_render")
True
reset(soft: bool = False) None
Reset the stage to its initial state and each object included in the Scene to its default state

as specified by the set_default_state and __init__ methods

Note

  • All tasks should be added before the first reset is called unless the clear method was called.

  • All articulations should be added before the first reset is called unless the clear method was called.

  • This method takes care of initializing articulation handles with the first reset called.

  • This will do one step internally regardless

  • Call post_reset on each object in the Scene

  • Call post_reset on each Task

Things like setting PD gains for instance should happen at a Task reset or a Robot reset since the defaults are restored after stop method is called.

Warning

This method is not intended to be used in the Isaac Sim’s Extensions workflow since the Kit application has the control over the rendering steps. For the Extensions workflow use the reset_async method instead

Parameters

soft (bool, optional) – if set to True simulation won’t be stopped and start again. It only calls the reset on the scene objects.

Example:

>>> world.reset()
async reset_async(soft: bool = False) None
Reset the stage to its initial state and each object included in the Scene to its default state

as specified by the set_default_state and __init__ methods

Note

  • All tasks should be added before the first reset is called unless the clear method was called.

  • All articulations should be added before the first reset is called unless the clear method was called.

  • This method takes care of initializing articulation handles with the first reset called.

  • This will do one step internally regardless

  • Call post_reset on each object in the Scene

  • Call post_reset on each Task

Things like setting PD gains for instance should happen at a Task reset or a Robot reset since the defaults are restored after stop method is called.

Parameters

soft (bool, optional) – if set to True simulation won’t be stopped and start again. It only calls the reset on the scene objects.

Example:

>>> from omni.kit.async_engine import run_coroutine
>>>
>>> async def task():
...     await world.reset_async()
...
>>> run_coroutine(task())
async reset_async_no_set_up_scene(soft: bool = False) None
Reset the stage to its initial state and each object included in the Scene to its default state

as specified by the set_default_state and __init__ methods

Note

  • All tasks should be added before the first reset is called unless the clear method was called.

  • All articulations should be added before the first reset is called unless the clear method was called.

  • This method takes care of initializing articulation handles with the first reset called.

  • This will do one step internally regardless

  • Call post_reset on each object in the Scene

  • Call post_reset on each Task

Things like setting PD gains for instance should happen at a Task reset or a Robot reset since the defaults are restored after stop method is called.

Parameters

soft (bool, optional) – if set to True simulation won’t be stopped and start again. It only calls the reset on the scene objects.

Example:

>>> from omni.kit.async_engine import run_coroutine
>>>
>>> async def task():
>>>     await world.reset_async_no_set_up_scene()
>>>
>>> run_coroutine(task())
async reset_async_set_up_scene(soft: bool = False) None
Reset the stage to its initial state and each object included in the Scene to its default state

as specified by the set_default_state and __init__ methods

Note

  • All tasks should be added before the first reset is called unless the clear method was called.

  • All articulations should be added before the first reset is called unless the clear method was called.

  • This method takes care of initializing articulation handles with the first reset called.

  • This will do one step internally regardless

  • Call post_reset on each object in the Scene

  • Call post_reset on each Task

Things like setting PD gains for instance should happen at a Task reset or a Robot reset since the defaults are restored after stop method is called.

Parameters

soft (bool, optional) – if set to True simulation won’t be stopped and start again. It only calls the reset on the scene objects.

Example:

>>> from omni.kit.async_engine import run_coroutine
>>>
>>> async def task():
>>>     await world.reset_async_set_up_scene()
>>>
>>> run_coroutine(task())
property scene: omni.isaac.core.scenes.scene.Scene
Returns

Scene instance

Return type

Scene

Example:

>>> world.scene
<omni.isaac.core.scenes.scene.Scene object at 0x>
set_block_on_render(block: bool) None

Set block on render flag for the simulation thread

Note

This guarantee a one frame lag between any data captured from the render products and the current USD stage if enabled.

Parameters

block (bool) – True to block the thread until the renderer is done.

Example:

>>> simulation_context.set_block_on_render(False)
set_simulation_dt(physics_dt: Optional[float] = None, rendering_dt: Optional[float] = None) None

Specify the physics step and rendering step size to use when stepping and rendering.

Parameters
  • physics_dt (float) – The physics time-step. None means it won’t change the current setting. (default: None).

  • rendering_dt (float) – The rendering time-step. None means it won’t change the current setting. (default: None)

Hint

It is recommended that the two values be divisible, with the rendering_dt being equal to or greater than the physics_dt

Example:

>>> set physics dt to 120 Hz and rendering dt to 60Hz (2 physics steps for each rendering)
>>> simulation_context.set_simulation_dt(physics_dt=1.0 / 120.0, rendering_dt=1.0 / 60.0)
property stage: pxr.Usd.Stage
Returns

current open USD stage

Return type

Usd.Stage

Example:

>>> simulation_context.stage
Usd.Stage.Open(rootLayer=Sdf.Find('anon:0x...:World....usd'),
               sessionLayer=Sdf.Find('anon:0x...:World...-session.usda'),
               pathResolverContext=<invalid repr>)
stage_callback_exists(callback_name: str) bool

Check if a stage callback exists

Parameters

callback_name (str) – callback name

Returns

whether the callback is registered

Return type

bool

Example:

>>> # given a registered callback named 'callback_stage'
>>> simulation_context.stage_callback_exists("callback_stage")
True
step(render: bool = True, step_sim: bool = True) None

Step the physics simulation while rendering or without.

Note

The pre_step for each task is called before stepping. This method also update the Bounding Box Cache time for computing bounding box if enabled

Warning

Calling this method with the render parameter set to True (default value) is not intended to be used in the Isaac Sim’s Extensions workflow since the Kit application has the control over the rendering steps

Parameters
  • render (bool, optional) – Set to False to only do a physics simulation without rendering. Note: app UI will be frozen (since its not rendering) in this case. Defaults to True.

  • step_sim (bool) – True to step simulation (physics and/or rendering)

Example:

>>> world.step()
step_async(step_size: Optional[float] = None) None

Call all functions that should be called pre stepping the physics

Note

The pre_step for each task is called before stepping. This method also update the Bounding Box Cache time for computing bounding box if enabled

Parameters

step_size (float) – step size

Example:

>>> from omni.kit.async_engine import run_coroutine
>>>
>>> async def task():
...     await world.step_async()
...
>>> run_coroutine(task())
stop() None

Stop the physics simulation

Example:

>>> simulation_context.stop()
async stop_async() None

Stop the physics simulation

Example:

>>> from omni.kit.async_engine import run_coroutine
>>>
>>> async def task():
...     await simulation_context.stop_async()
...
>>> run_coroutine(task())
timeline_callback_exists(callback_name: str) bool

Check if a timeline callback exists

Parameters

callback_name (str) – callback name

Returns

whether the callback is registered

Return type

bool

Example:

>>> # given a registered callback named 'callback_timeline'
>>> simulation_context.timeline_callback_exists("callback_timeline")
True

Tasks

Base Task

class BaseTask(name: str, offset: Optional[numpy.ndarray] = None)

This class provides a way to set up a task in a scene and modularize adding objects to stage, getting observations needed for the behavioral layer, calculating metrics needed about the task, calling certain things pre-stepping, creating multiple tasks at the same time and much more.

Checkout the required tutorials at https://docs.omniverse.nvidia.com/app_isaacsim/app_isaacsim/overview.html

Parameters
  • name (str) – needs to be unique if added to the World.

  • offset (Optional[np.ndarray], optional) – offset applied to all assets of the task.

calculate_metrics() dict

[summary]

Raises

NotImplementedError – [description]

cleanup() None

Called before calling a reset() on the world to removed temporary objects that were added during simulation for instance.

property device
get_description() str

[summary]

Returns

[description]

Return type

str

get_observations() dict

Returns current observations from the objects needed for the behavioral layer.

Raises

NotImplementedError – [description]

Returns

[description]

Return type

dict

get_params() dict
Gets the parameters of the task.

This is defined differently for each task in order to access the task’s objects and values. Note that this is different from get_observations. Things like the robot name, block name..etc can be defined here for faster retrieval. should have the form of params_representation[“param_name”] = {“value”: param_value, “modifiable”: bool}

Raises

NotImplementedError – [description]

Returns

defined parameters of the task.

Return type

dict

get_task_objects() dict

[summary]

Returns

[description]

Return type

dict

is_done() bool

Returns True of the task is done.

Raises

NotImplementedError – [description]

property name: str

[summary]

Returns

[description]

Return type

str

post_reset() None

Calls while doing a .reset() on the world.

pre_step(time_step_index: int, simulation_time: float) None

called before stepping the physics simulation.

Parameters
  • time_step_index (int) – [description]

  • simulation_time (float) – [description]

property scene: omni.isaac.core.scenes.scene.Scene

Scene of the world

Returns

[description]

Return type

Scene

set_params(*args, **kwargs) None

Changes the modifiable parameters of the task

Raises

NotImplementedError – [description]

set_up_scene(scene: omni.isaac.core.scenes.scene.Scene) None
Adding assets to the stage as well as adding the encapsulated objects such as XFormPrim..etc

to the task_objects happens here.

Parameters

scene (Scene) – [description]

Follow Target

class FollowTarget(name: str, target_prim_path: Optional[str] = None, target_name: Optional[str] = None, target_position: Optional[numpy.ndarray] = None, target_orientation: Optional[numpy.ndarray] = None, offset: Optional[numpy.ndarray] = None)

[summary]

Parameters
  • name (str) – [description]

  • target_prim_path (Optional[str], optional) – [description]. Defaults to None.

  • target_name (Optional[str], optional) – [description]. Defaults to None.

  • target_position (Optional[np.ndarray], optional) – [description]. Defaults to None.

  • target_orientation (Optional[np.ndarray], optional) – [description]. Defaults to None.

  • offset (Optional[np.ndarray], optional) – [description]. Defaults to None.

add_obstacle(position: Optional[numpy.ndarray] = None)

[summary]

Parameters

position (np.ndarray, optional) – [description]. Defaults to np.array([0.1, 0.1, 1.0]).

calculate_metrics() dict

[summary]

cleanup() None

[summary]

property device
get_description() str

[summary]

Returns

[description]

Return type

str

get_observations() dict

[summary]

Returns

[description]

Return type

dict

get_obstacle_to_delete() None

[summary]

Returns

[description]

Return type

[type]

get_params() dict

[summary]

Returns

[description]

Return type

dict

get_task_objects() dict

[summary]

Returns

[description]

Return type

dict

is_done() bool

[summary]

property name: str

[summary]

Returns

[description]

Return type

str

obstacles_exist() bool

[summary]

Returns

[description]

Return type

bool

post_reset() None

[summary]

pre_step(time_step_index: int, simulation_time: float) None

[summary]

Parameters
  • time_step_index (int) – [description]

  • simulation_time (float) – [description]

remove_obstacle(name: Optional[str] = None) None

[summary]

Parameters

name (Optional[str], optional) – [description]. Defaults to None.

property scene: omni.isaac.core.scenes.scene.Scene

Scene of the world

Returns

[description]

Return type

Scene

set_params(target_prim_path: Optional[str] = None, target_name: Optional[str] = None, target_position: Optional[numpy.ndarray] = None, target_orientation: Optional[numpy.ndarray] = None) None

[summary]

Parameters
  • target_prim_path (Optional[str], optional) – [description]. Defaults to None.

  • target_name (Optional[str], optional) – [description]. Defaults to None.

  • target_position (Optional[np.ndarray], optional) – [description]. Defaults to None.

  • target_orientation (Optional[np.ndarray], optional) – [description]. Defaults to None.

abstract set_robot() None

[summary]

Raises

NotImplementedError – [description]

set_up_scene(scene: omni.isaac.core.scenes.scene.Scene) None

[summary]

Parameters

scene (Scene) – [description]

target_reached() bool

[summary]

Returns

[description]

Return type

bool

Pick and Place

class PickPlace(name: str, cube_initial_position: Optional[numpy.ndarray] = None, cube_initial_orientation: Optional[numpy.ndarray] = None, target_position: Optional[numpy.ndarray] = None, cube_size: Optional[numpy.ndarray] = None, offset: Optional[numpy.ndarray] = None)

[summary]

Parameters
  • name (str) – [description]

  • cube_initial_position (Optional[np.ndarray], optional) – [description]. Defaults to None.

  • cube_initial_orientation (Optional[np.ndarray], optional) – [description]. Defaults to None.

  • target_position (Optional[np.ndarray], optional) – [description]. Defaults to None.

  • cube_size (Optional[np.ndarray], optional) – [description]. Defaults to None.

  • offset (Optional[np.ndarray], optional) – [description]. Defaults to None.

calculate_metrics() dict

[summary]

cleanup() None

Called before calling a reset() on the world to removed temporary objects that were added during simulation for instance.

property device
get_description() str

[summary]

Returns

[description]

Return type

str

get_observations() dict

[summary]

Returns

[description]

Return type

dict

get_params() dict
Gets the parameters of the task.

This is defined differently for each task in order to access the task’s objects and values. Note that this is different from get_observations. Things like the robot name, block name..etc can be defined here for faster retrieval. should have the form of params_representation[“param_name”] = {“value”: param_value, “modifiable”: bool}

Raises

NotImplementedError – [description]

Returns

defined parameters of the task.

Return type

dict

get_task_objects() dict

[summary]

Returns

[description]

Return type

dict

is_done() bool

[summary]

property name: str

[summary]

Returns

[description]

Return type

str

post_reset() None

Calls while doing a .reset() on the world.

pre_step(time_step_index: int, simulation_time: float) None

[summary]

Parameters
  • time_step_index (int) – [description]

  • simulation_time (float) – [description]

property scene: omni.isaac.core.scenes.scene.Scene

Scene of the world

Returns

[description]

Return type

Scene

set_params(cube_position: Optional[numpy.ndarray] = None, cube_orientation: Optional[numpy.ndarray] = None, target_position: Optional[numpy.ndarray] = None) None

Changes the modifiable parameters of the task

Raises

NotImplementedError – [description]

abstract set_robot() None
set_up_scene(scene: omni.isaac.core.scenes.scene.Scene) None

[summary]

Parameters

scene (Scene) – [description]

Stacking

class Stacking(name: str, cube_initial_positions: numpy.ndarray, cube_initial_orientations: Optional[numpy.ndarray] = None, stack_target_position: Optional[numpy.ndarray] = None, cube_size: Optional[numpy.ndarray] = None, offset: Optional[numpy.ndarray] = None)

[summary]

Parameters
  • name (str) – [description]

  • cube_initial_positions (np.ndarray) – [description]

  • cube_initial_orientations (Optional[np.ndarray], optional) – [description]. Defaults to None.

  • stack_target_position (Optional[np.ndarray], optional) – [description]. Defaults to None.

  • cube_size (Optional[np.ndarray], optional) – [description]. Defaults to None.

  • offset (Optional[np.ndarray], optional) – [description]. Defaults to None.

calculate_metrics() dict

[summary]

Raises

NotImplementedError – [description]

Returns

[description]

Return type

dict

cleanup() None

Called before calling a reset() on the world to removed temporary objects that were added during simulation for instance.

property device
get_cube_names() List[str]

[summary]

Returns

[description]

Return type

List[str]

get_description() str

[summary]

Returns

[description]

Return type

str

get_observations() dict

[summary]

Returns

[description]

Return type

dict

get_params() dict

[summary]

Returns

[description]

Return type

dict

get_task_objects() dict

[summary]

Returns

[description]

Return type

dict

is_done() bool

[summary]

Raises

NotImplementedError – [description]

Returns

[description]

Return type

bool

property name: str

[summary]

Returns

[description]

Return type

str

post_reset() None

[summary]

pre_step(time_step_index: int, simulation_time: float) None

[summary]

Parameters
  • time_step_index (int) – [description]

  • simulation_time (float) – [description]

property scene: omni.isaac.core.scenes.scene.Scene

Scene of the world

Returns

[description]

Return type

Scene

set_params(cube_name: Optional[str] = None, cube_position: Optional[str] = None, cube_orientation: Optional[str] = None, stack_target_position: Optional[str] = None) None

[summary]

Parameters
  • cube_name (Optional[str], optional) – [description]. Defaults to None.

  • cube_position (Optional[str], optional) – [description]. Defaults to None.

  • cube_orientation (Optional[str], optional) – [description]. Defaults to None.

  • stack_target_position (Optional[str], optional) – [description]. Defaults to None.

abstract set_robot() None

[summary]

Raises

NotImplementedError – [description]

set_up_scene(scene: omni.isaac.core.scenes.scene.Scene) None

[summary]

Parameters

scene (Scene) – [description]

Utils


Bounds Utils

Utils for computing the Axis-Aligned Bounding Box (AABB) and the Oriented Bounding Box (OBB) of a prim.

  • The AABB is the smallest cuboid that can completely contain the prim it represents. It is defined by the following 3D coordinates: \((x_{min}, y_{min}, z_{min}, x_{max}, y_{max}, z_{max})\).

  • Unlike the AABB, which is aligned with the coordinate axes, the OBB can be oriented at any angle in 3D space.

compute_aabb(bbox_cache: pxr.UsdGeom.BBoxCache, prim_path: str, include_children: bool = False) numpy.array

Compute an Axis-Aligned Bounding Box (AABB) for a given prim_path

A combined AABB is computed if include_children is True

Parameters
  • bbox_cache (UsdGeom.BboxCache) – Existing Bounding box cache to use for computation

  • prim_path (str) – prim path to compute AABB for

  • include_children (bool, optional) – include children of specified prim in calculation. Defaults to False.

Returns

Bounding box for this prim, [min x, min y, min z, max x, max y, max z]

Return type

np.array

Example:

>>> import omni.isaac.core.utils.bounds as bounds_utils
>>>
>>> # 1 stage unit length cube centered at (0.0, 0.0, 0.0)
>>> cache = bounds_utils.create_bbox_cache()
>>> bounds_utils.compute_aabb(cache, prim_path="/World/Cube")
[-0.5 -0.5 -0.5  0.5  0.5  0.5]
>>>
>>> # the same cube rotated 45 degrees around the z-axis
>>> cache = bounds_utils.create_bbox_cache()
>>> bounds_utils.compute_aabb(cache, prim_path="/World/Cube")
[-0.70710678  -0.70710678  -0.5  0.70710678  0.70710678  0.5]
compute_combined_aabb(bbox_cache: pxr.UsdGeom.BBoxCache, prim_paths: List[str]) numpy.array

Computes a combined Axis-Aligned Bounding Box (AABB) given a list of prim paths

Parameters
  • bbox_cache (UsdGeom.BboxCache) – Existing Bounding box cache to use for computation

  • prim_paths (List[str]) – List of prim paths to compute combined AABB for

Returns

Bounding box for input prims, [min x, min y, min z, max x, max y, max z]

Return type

np.array

Example:

>>> import omni.isaac.core.utils.bounds as bounds_utils
>>>
>>> # 1 stage unit length cube centered at (0.0, 0.0, 0.0)
>>> # with a 1 stage unit diameter sphere centered at (-0.5, 0.5, 0.5)
>>> cache = bounds_utils.create_bbox_cache()
>>> bounds_utils.compute_combined_aabb(cache, prim_paths=["/World/Cube", "/World/Sphere"])
[-1.  -0.5 -0.5  0.5  1.   1. ]
compute_obb(bbox_cache: pxr.UsdGeom.BBoxCache, prim_path: str) Tuple[numpy.ndarray, numpy.ndarray, numpy.ndarray]

Computes the Oriented Bounding Box (OBB) of a prim

Note

  • The OBB does not guarantee the smallest possible bounding box, it rotates and scales the default AABB.

  • The rotation matrix incorporates any scale factors applied to the object.

  • The half_extent values do not include these scaling effects.

Parameters
  • bbox_cache (UsdGeom.BBoxCache) – USD Bounding Box Cache object to use for computation

  • prim_path (str) – Prim path to compute OBB for

Returns

A tuple containing the following OBB information:
  • The centroid of the OBB as a NumPy array.

  • The axes of the OBB as a 2D NumPy array, where each row represents a different axis.

  • The half extent of the OBB as a NumPy array.

Return type

Tuple[np.ndarray, np.ndarray, np.ndarray]

Example:

>>> import omni.isaac.core.utils.bounds as bounds_utils
>>>
>>> # 1 stage unit length cube centered at (0.0, 0.0, 0.0)
>>> cache = bounds_utils.create_bbox_cache()
>>> centroid, axes, half_extent = bounds_utils.compute_obb(cache, prim_path="/World/Cube")
>>> centroid
[0. 0. 0.]
>>> axes
[[1. 0. 0.]
 [0. 1. 0.]
 [0. 0. 1.]]
>>> half_extent
[0.5 0.5 0.5]
>>>
>>> # the same cube rotated 45 degrees around the z-axis
>>> cache = bounds_utils.create_bbox_cache()
>>> centroid, axes, half_extent = bounds_utils.compute_obb(cache, prim_path="/World/Cube")
>>> centroid
[0. 0. 0.]
>>> axes
[[ 0.70710678  0.70710678  0.        ]
 [-0.70710678  0.70710678  0.        ]
 [ 0.          0.          1.        ]]
>>> half_extent
[0.5 0.5 0.5]
compute_obb_corners(bbox_cache: pxr.UsdGeom.BBoxCache, prim_path: str) numpy.ndarray

Computes the corners of the Oriented Bounding Box (OBB) of a prim

Parameters
  • bbox_cache (UsdGeom.BBoxCache) – Bounding Box Cache object to use for computation

  • prim_path (str) – Prim path to compute OBB for

Returns

NumPy array of shape (8, 3) containing each corner location of the OBB

\(c_0 = (x_{min}, y_{min}, z_{min})\)
\(c_1 = (x_{min}, y_{min}, z_{max})\)
\(c_2 = (x_{min}, y_{max}, z_{min})\)
\(c_3 = (x_{min}, y_{max}, z_{max})\)
\(c_4 = (x_{max}, y_{min}, z_{min})\)
\(c_5 = (x_{max}, y_{min}, z_{max})\)
\(c_6 = (x_{max}, y_{max}, z_{min})\)
\(c_7 = (x_{max}, y_{max}, z_{max})\)

Return type

np.ndarray

Example:

>>> import omni.isaac.core.utils.bounds as bounds_utils
>>>
>>> cache = bounds_utils.create_bbox_cache()
>>> bounds_utils.compute_obb_corners(cache, prim_path="/World/Cube")
[[-0.5 -0.5 -0.5]
 [-0.5 -0.5  0.5]
 [-0.5  0.5 -0.5]
 [-0.5  0.5  0.5]
 [ 0.5 -0.5 -0.5]
 [ 0.5 -0.5  0.5]
 [ 0.5  0.5 -0.5]
 [ 0.5  0.5  0.5]]
create_bbox_cache(time: pxr.Usd.TimeCode = Usd.TimeCode.Default(), use_extents_hint: bool = True) pxr.UsdGeom.BBoxCache

Helper function to create a Bounding Box Cache object that can be used for computations

Parameters
  • time (Usd.TimeCode, optional) – time at which cache should be initialized. Defaults to Usd.TimeCode.Default().

  • use_extents_hint (bool, optional) – Use existing extents attribute on prim to compute bounding box. Defaults to True.

Returns

Initialized bbox cache

Return type

UsdGeom.BboxCache

Example:

>>> import omni.isaac.core.utils.bounds as bounds_utils
>>>
>>> bounds_utils.create_bbox_cache()
<pxr.UsdGeom.BBoxCache object at 0x7f6720b8bc90>
get_obb_corners(centroid: numpy.ndarray, axes: numpy.ndarray, half_extent: numpy.ndarray) numpy.ndarray

Computes the corners of the Oriented Bounding Box (OBB) from the given OBB information

Parameters
  • centroid (np.ndarray) – The centroid of the OBB as a NumPy array.

  • axes (np.ndarray) – The axes of the OBB as a 2D NumPy array, where each row represents a different axis.

  • half_extent (np.ndarray) – The half extent of the OBB as a NumPy array.

Returns

NumPy array of shape (8, 3) containing each corner location of the OBB

\(c_0 = (x_{min}, y_{min}, z_{min})\)
\(c_1 = (x_{min}, y_{min}, z_{max})\)
\(c_2 = (x_{min}, y_{max}, z_{min})\)
\(c_3 = (x_{min}, y_{max}, z_{max})\)
\(c_4 = (x_{max}, y_{min}, z_{min})\)
\(c_5 = (x_{max}, y_{min}, z_{max})\)
\(c_6 = (x_{max}, y_{max}, z_{min})\)
\(c_7 = (x_{max}, y_{max}, z_{max})\)

Return type

np.ndarray

Example:

>>> import omni.isaac.core.utils.bounds as bounds_utils
>>>
>>> cache = bounds_utils.create_bbox_cache()
>>> centroid, axes, half_extent = bounds_utils.compute_obb(cache, prim_path="/World/Cube")
>>> bounds_utils.get_obb_corners(centroid, axes, half_extent)
[[-0.5 -0.5 -0.5]
 [-0.5 -0.5  0.5]
 [-0.5  0.5 -0.5]
 [-0.5  0.5  0.5]
 [ 0.5 -0.5 -0.5]
 [ 0.5 -0.5  0.5]
 [ 0.5  0.5 -0.5]
 [ 0.5  0.5  0.5]]
recompute_extents(prim: pxr.UsdGeom.Boundable, time: pxr.Usd.TimeCode = Usd.TimeCode.Default(), include_children: bool = False) None

Recomputes and overwrites the extents attribute for a UsdGeom.Boundable prim

Parameters
  • prim (UsdGeom.Boundable) – Input prim to recompute extents for

  • time (Usd.TimeCode, optional) – timecode to use for computing extents. Defaults to Usd.TimeCode.Default().

  • include_children (bool, optional) – include children of specified prim in calculation. Defaults to False.

Raises

ValueError – If prim is not of UsdGeom.Boundable type

Example:

>>> import omni.isaac.core.utils.bounds as bounds_utils
>>> import omni.isaac.core.utils.stage as stage_utils
>>>
>>> prim = stage_utils.get_current_stage().GetPrimAtPath("/World/Cube")
>>> bounds_utils.recompute_extents(prim)

Carb Utils

Carb settings is a generalized subsystem designed to provide a simple to use interface to Kit’s various subsystems, which can be automated, enumerated, serialized and so on.

The most common types of settings are:

  • Persistent (saved between sessions): "/persistent/<setting>"
    (e.g., "/persistent/physics/updateToUsd")

  • Application: "/app/<setting>" (e.g., "/app/viewport/grid/enabled")

  • Extension: "/exts/<extension>/<setting>" (e.g., "/exts/omni.kit.debug.python/host")

get_carb_setting(carb_settings: carb.settings._settings.ISettings, setting: str) Any

Convenience function to get settings.

Parameters
  • carb_settings (carb.settings.ISettings) – The interface to carb settings.

  • setting (str) – Name of setting to change.

Returns

Value for the setting.

Return type

Any

Example:

>>> import carb
>>> import omni.isaac.core.utils.carb as carb_utils
>>>
>>> settings = carb.settings.get_settings()
>>> carb_utils.get_carb_setting(settings, "/persistent/physics/updateToUsd")
False
set_carb_setting(carb_settings: carb.settings._settings.ISettings, setting: str, value: Any) None

Convenience to set the carb settings.

Parameters
  • carb_settings (carb.settings.ISettings) – The interface to carb settings.

  • setting (str) – Name of setting to change.

  • value (Any) – New value for the setting.

Raises

TypeError – If the type of value does not match setting type.

Example:

>>> import carb
>>> import omni.isaac.core.utils.carb as carb_utils
>>>
>>> settings = carb.settings.get_settings()
>>> carb_utils.set_carb_setting(settings, "/persistent/physics/updateToUsd", True)

Collisions Utils

ray_cast(position: numpy.array, orientation: numpy.array, offset: numpy.array, max_dist: float = 100.0) Tuple[Union[None, str], float]

Projects a raycast forward along x axis with specified offset

If a hit is found within the maximum distance, then the object’s prim path and distance to it is returned. Otherwise, a None and 10000 is returned.

Parameters
  • position (np.array) – origin’s position for ray cast

  • orientation (np.array) – origin’s orientation for ray cast

  • offset (np.array) – offset for ray cast

  • max_dist (float, optional) – maximum distance to test for collisions in stage units. Defaults to 100.0.

Returns

path to geometry that was hit and hit distance, returns None, 10000 if no hit occurred

Return type

Tuple[Union[None, str], float]


Constants Utils

AXES_INDICES = {'X': 0, 'Y': 1, 'Z': 2, 'x': 0, 'y': 1, 'z': 2}

Mapping from axis name to axis ID

Example:

>>> import omni.isaac.core.utils.constants as constants_utils
>>>
>>> # get the x-axis index
>>> constants_utils.AXES_INDICES['x']
0
>>> constants_utils.AXES_INDICES['X']
0
AXES_TOKEN = {'X': 'X', 'Y': 'Y', 'Z': 'Z', 'x': 'X', 'y': 'Y', 'z': 'Z'}

Mapping from axis name to axis USD token

>>> import omni.isaac.core.utils.constants as constants_utils
>>>
>>> # get the x-axis USD token
>>> constants_utils.AXES_TOKEN['x']
X
>>> constants_utils.AXES_TOKEN['X']
X

Distance Metrics Utils

rotational_distance_angle(r1: Union[numpy.ndarray, pxr.Gf.Matrix3d, pxr.Gf.Matrix4d], r2: Union[numpy.ndarray, pxr.Gf.Matrix3d, pxr.Gf.Matrix4d]) numpy.ndarray

Computes the weighted distance between two rotations using inner product.

Note

If r1 and r2 are GfMatrix3d() objects, the transformation matrices will be transposed in the distance calculations.

Parameters
  • r1 (Union[np.ndarray, Gf.Matrix3d, Gf.Matrix4d]) – rotation matrices or 4x4 transformation matrices

  • r2 (Union[np.ndarray, Gf.Matrix3d, Gf.Matrix4d]) – rotation matrices or 4x4 transformation matrices

Returns

the magnitude of the angle of rotation from r1 to r2

Return type

np.ndarray

rotational_distance_identity_matrix_deviation(r1: Union[numpy.ndarray, pxr.Gf.Matrix4d, pxr.Gf.Matrix3d], r2: Union[numpy.ndarray, pxr.Gf.Matrix4d, pxr.Gf.Matrix3d]) numpy.ndarray

Computes the distance between two rotations using deviation from identity matrix.

Note

If r1 and r2 are GfMatrix3d() objects, the transformation matrices will be transposed in the distance calculations.

Parameters
  • r1 (Union[np.ndarray, Gf.Matrix4d, Gf.Matrix3d]) – rotation matrices or 4x4 transformation matrices

  • r2 (Union[np.ndarray, Gf.Matrix4d, Gf.Matrix3d]) – rotation matrices or 4x4 transformation matrices

Returns

the Frobenius norm |I-r1*r2^T|, where I is the identity matrix

Return type

np.ndarray

rotational_distance_single_axis(r1: Union[numpy.ndarray, pxr.Gf.Matrix4d, pxr.Gf.Matrix3d], r2: Union[numpy.ndarray, pxr.Gf.Matrix4d, pxr.Gf.Matrix3d], axis: numpy.ndarray) numpy.ndarray

Computes the distance between two rotations w.r.t. input axis.

Note

If r1 and r2 are GfMatrix3d() objects, the transformation matrices will be transposed in the distance calculations.

Usage:

If the robot were holding a cup aligned with its z-axis, it would be important to align the z-axis of the robot with the z-axis of the world frame. This could be accomplished by letting

-r1 be the rotation of the robot end effector
-r2 be any rotation matrix for a rotation about the z axis
-axis = [0,0,1]
Parameters
  • r1 (Union[np.ndarray, Gf.Matrix4d, Gf.Matrix3d]) – rotation matrices or 4x4 transformation matrices

  • r2 (Union[np.ndarray, Gf.Matrix4d, Gf.Matrix3d]) – rotation matrices or 4x4 transformation matrices

  • axis (np.ndarray) – a 3d vector that will be rotated by r1 and r2

Returns

the angle between (r1 @ axis) and (r2 @ axis)

Return type

np.ndarray

weighted_translational_distance(t1: Union[numpy.ndarray, pxr.Gf.Matrix4d], t2: Union[numpy.ndarray, pxr.Gf.Matrix4d], weight_matrix: numpy.ndarray = array([[1., 0., 0.], [0., 1., 0.], [0., 0., 1.]])) numpy.ndarray

Computes the weighted distance between two translation vectors.

The distance calculation has the form sqrt(x.T W x), where

- x is the vector difference between t1 and t2.
- W is a weight matrix.

Given the identity weight matrix, this is equivalent to the |t1-t2|.

Usage:

This formulation can be used to weight an arbitrary axis of the translation difference. Letting x = t1-t2 = a1*b1 + a2*b2 + a3*b3 (where b1,b2,b3 are column basis vectors, and a1,a2,a3 are constants), When W = I: x.T W x = sqrt(a1^2 + a2^2 + a3^2). To weight the b1 axis by 2, let W take the form (R.T @ ([4,1,1]@I) @ R) where:

- I is the identity matrix.
- R is a rotation matrix of the form [b1,b2,b3].T

This is effectively equivalent to |[2*e1,e2,e3] @ [b1,b2,b3].T @ x| = sqrt(4*a1^2 + a2^2 + a3^2).

- e1,e2,e3 are the elementary basis vectors.
Parameters
  • t1 (Union[np.ndarray, Gf.Matrix4d]) – 3d translation vectors or 4x4 transformation matrices

  • t2 (Union[np.ndarray, Gf.Matrix4d]) – 3d translation vectors or 4x4 transformation matrices

  • weight_matrix (np.ndarray, optional) – a 3x3 positive semidefinite matrix of weights. Defaults to np.eye(3).

Returns

the weighted norm of the difference (t1-t2)

Return type

np.ndarray


Extensions Utils

Utilities for enabling and disabling extensions from the Extension Manager and knowing their locations

disable_extension(extension_name: str) bool

Unload an extension.

Parameters

extension_name (str) – name of the extension

Returns

True if extension could be unloaded, False otherwise

Return type

bool

Example:

>>> import omni.isaac.core.utils.extensions as extensions_utils
>>>
>>> extensions_utils.disable_extension("omni.kit.window.stage")
True
enable_extension(extension_name: str) bool

Load an extension from the extension manager.

Parameters

extension_name (str) – name of the extension

Returns

True if extension could be loaded, False otherwise

Return type

bool

Example:

>>> import omni.isaac.core.utils.extensions as extensions_utils
>>>
>>> extensions_utils.enable_extension("omni.kit.window.stage")
True
get_extension_id(extension_name: str) str

Get extension id for a loaded extension

Parameters

extension_name (str) – name of the extension

Returns

Full extension id

Return type

str

Example:

>>> import omni.isaac.core.utils.extensions as extensions_utils
>>>
>>> extensions_utils.get_extension_id("omni.kit.window.stage")
omni.kit.window.stage-2.4.3
get_extension_path(ext_id: str) str

Get extension path for a loaded extension by its full id

Parameters

ext_id (str) – full id of extension

Returns

Path to loaded extension root directory

Return type

str

Example:

>>> import omni.isaac.core.utils.extensions as extensions_utils
>>>
>>> ext_id = extensions_utils.get_extension_id("omni.kit.window.stage")
>>> extensions_utils.get_extension_path(ext_id)
/home/user/.local/share/ov/pkg/isaac_sim-<version>/kit/exts/omni.kit.window.stage
get_extension_path_from_name(extension_name: str) str

Get extension path for a loaded extension by its name

Parameters

extension_name (str) – name of the extension

Returns

Path to loaded extension root directory

Return type

str

Example:

>>> import omni.isaac.core.utils.extensions as extensions_utils
>>>
>>> extensions_utils.get_extension_path_from_name("omni.kit.window.stage")
/home/user/.local/share/ov/pkg/isaac_sim-<version>/kit/exts/omni.kit.window.stage

Math Utils

cross(a: Union[numpy.ndarray, list], b: Union[numpy.ndarray, list]) list

Computes the cross-product between two 3-dimensional vectors.

Parameters
  • a (np.ndarray, list) – A 3-dimensional vector

  • b (np.ndarray, list) – A 3-dimensional vector

Returns

Cross product between input vectors.

Return type

np.ndarray

normalize(v)

Normalizes the vector inline (and also returns it).

normalized(v)

Returns a normalized copy of the provided vector.

radians_to_degrees(rad_angles: numpy.ndarray) numpy.ndarray

Converts input angles from radians to degrees.

Parameters

rad_angles (np.ndarray) – Input array of angles (in radians).

Returns

Array of angles in degrees.

Return type

np.ndarray


Mesh Utils

get_mesh_vertices_relative_to(mesh_prim: pxr.UsdGeom.Mesh, coord_prim: pxr.Usd.Prim) numpy.ndarray

Get vertices of the mesh prim in the coordinate system of the given prim.

Parameters
  • mesh_prim (UsdGeom.Mesh) – mesh prim to get the vertice points.

  • coord_prim (Usd.Prim) – prim used as relative coordinate.

Returns

vertices of the mesh in the coordinate system of the given prim. Shape is (N, 3).

Return type

np.ndarray

Example:

>>> import omni.isaac.core.utils.mesh as mesh_utils
>>> import omni.isaac.core.utils.stage as stage_utils
>>>
>>> # 1 stage unit length cube centered at (0.0, 0.0, 0.0)
>>> mesh_prim = stage_utils.get_current_stage().GetPrimAtPath("/World/Cube")
>>> # 1 stage unit diameter sphere centered at (1.0, 1.0, 1.0)
>>> coord_prim = stage_utils.get_current_stage().GetPrimAtPath("/World/Sphere")
>>>
>>> mesh_utils.get_mesh_vertices_relative_to(mesh_prim, coord_prim)
[[-1.5 -1.5 -0.5]
 [-0.5 -1.5 -0.5]
 [-1.5 -0.5 -0.5]
 [-0.5 -0.5 -0.5]
 [-1.5 -1.5 -1.5]
 [-0.5 -1.5 -1.5]
 [-1.5 -0.5 -1.5]
 [-0.5 -0.5 -1.5]]

Nucleus Utils

class Version(s)
build_server_list() List

Return list with all known servers to check

Returns

List of servers found

Return type

all_servers (List)

check_server(server: str, path: str, timeout: float = 10.0) bool

Check a specific server for a path

Parameters
  • server (str) – Name of Nucleus server

  • path (str) – Path to search

  • timeout (float) – Default value: 10 seconds

Returns

True if folder is found

Return type

bool

async check_server_async(server: str, path: str, timeout: float = 10.0) bool

Check a specific server for a path (asynchronous version).

Parameters
  • server (str) – Name of Nucleus server

  • path (str) – Path to search

  • timeout (float) – Default value: 10 seconds

Returns

True if folder is found

Return type

bool

create_folder(server: str, path: str) bool

Create a folder on server

Parameters
  • server (str) – Name of Nucleus server

  • path (str) – Path to folder

Returns

True if folder is created successfully

Return type

bool

delete_folder(server: str, path: str) bool

Remove folder and all of its contents

Parameters
  • server (str) – Name of Nucleus server

  • path (str) – Path to folder

Returns

True if folder is deleted successfully

Return type

bool

async download_assets_async(src: str, dst: str, progress_callback, concurrency: int = 10, copy_behaviour: omni.client.CopyBehavior = CopyBehavior.OVERWRITE, copy_after_delete: bool = True, timeout: float = 300.0) omni.client.Result

Download assets from S3 bucket

Parameters
  • src (str) – URL of S3 bucket as source

  • dst (str) – URL of Nucleus server to copy assets to

  • progress_callback – Callback function to keep track of progress of copy

  • concurrency (int) – Number of concurrent copy operations. Default value: 3

  • copy_behaviour (omni.client._omniclient.CopyBehavior) – Behavior if the destination exists. Default value: OVERWRITE

  • copy_after_delete (bool) – True if destination needs to be deleted before a copy. Default value: True

  • timeout (float) – Default value: 300 seconds

Returns

Result of copy

Return type

Result (omni.client._omniclient.Result)

find_nucleus_server(suffix: str) Tuple[bool, str]

Attempts to determine best Nucleus server to use based on existing mountedDrives setting and the default server specified in json config at “/persistent/isaac/asset_root/”. Call is blocking

Parameters

suffix (str) – Path to folder to search for. Default value: /Isaac

Returns

True if Nucleus server with suffix is found url (str): URL of found Nucleus

Return type

bool

get_assets_root_path() Optional[str]

Tries to find the root path to the Isaac Sim assets on a Nucleus server

Returns

URL of Nucleus server with root path to assets folder. Returns None if Nucleus server not found.

Return type

url (str)

async get_assets_root_path_async() Optional[str]

Tries to find the root path to the Isaac Sim assets on a Nucleus server (asynchronous version).

Returns

URL of Nucleus server with root path to assets folder. Returns None if Nucleus server not found.

Return type

url (str)

get_assets_server() Optional[str]

Tries to find a server with the Isaac Sim assets

Returns

URL of Nucleus server with the Isaac Sim assets

Returns None if Nucleus server not found.

Return type

url (str)

get_full_asset_path(path: str) Optional[str]

Tries to find the full asset path on connected servers

Parameters

path (str) – Path of asset from root to verify

Returns

URL or full path to assets. Returns None if assets not found.

Return type

url (str)

async get_full_asset_path_async(path: str) Optional[str]

Tries to find the full asset path on connected servers (asynchronous version).

Parameters

path (str) – Path of asset from root to verify

Returns

URL or full path to assets. Returns None if assets not found.

Return type

url (str)

get_isaac_asset_root_path() Optional[str]

Tries to find the root path to the Isaac Sim assets

Returns

URL or root path to Isaac Sim assets folder. Returns None if Isaac Sim assets not found.

Return type

url (str)

get_nvidia_asset_root_path() Optional[str]

Tries to find the root path to the NVIDIA assets

Returns

URL or root path to NVIDIA assets folder. Returns None if NVIDIA assets not found.

Return type

url (str)

get_server_path(suffix: str = '') Optional[str]

Tries to find a Nucleus server with specific path

Parameters

suffix (str) – Path to folder to search for.

Returns

URL of Nucleus server with path to folder. Returns None if Nucleus server not found.

Return type

url (str)

async get_server_path_async(suffix: str = '') Optional[str]

Tries to find a Nucleus server with specific path (asynchronous version).

Parameters

suffix (str) – Path to folder to search for.

Returns

URL of Nucleus server with path to folder. Returns None if Nucleus server not found.

Return type

url (str)

get_url_root(url: str) str

Get root from URL or path :param url: full http or omniverse path :type url: str

Returns

Root path or URL or Nucleus server

Return type

str

async is_dir_async(path: str) bool

Check if path is a folder

Parameters

path (str) – Path to folder

Returns

True if path is a folder

Return type

bool

is_file(path: str) bool

Check if path is a file

Parameters

path (str) – Path to file

Returns

True if path is a file

Return type

bool

async is_file_async(path: str) bool

Check if path is a file

Parameters

path (str) – Path to file

Returns

True if path is a file

Return type

bool

async list_folder(path: str) Tuple[List, List]

List files and sub-folders from root path

Parameters

path (str) – Path to root folder

Raises

Exception – When unable to find files under the path.

Returns

List of path to each file dirs (typing.List): List of path to each sub-folder

Return type

files (List)

async recursive_list_folder(path: str) List

Recursively list all files

Parameters

path (str) – Path to folder

Returns

List of path to each file

Return type

paths (List)

verify_asset_root_path(path: str) Tuple[omni.client.Result, str]

Attempts to determine Isaac assets version and check if there are updates. (asynchronous version)

Parameters

path (str) – URL or path of asset root to verify

Returns

OK if Assets verified ver (str): Version of Isaac Sim assets

Return type

omni.client.Result


Physics Utils

get_rigid_body_enabled(prim_path: str) Optional[bool]

Get the physics:rigidBodyEnabled attribute from the USD Prim at the given path

Parameters

prim_path (str) – The path to the USD Prim

Returns

The value of physics:rigidBodyEnabled attribute if it exists, and None if it does not exist.

Return type

Any

Example:

>>> import omni.isaac.core.utils.physics as physics_utils
>>>
>>> # prim without the Physics' Rigid Body property
>>> physics_utils.get_rigid_body_enabled("/World/Cube")
None
>>> # prim with the physics Rigid Body property added and enabled
>>> physics_utils.get_rigid_body_enabled("/World/Cube")
True
set_rigid_body_enabled(_value, prim_path)

If it exists, set the physics:rigidBodyEnabled attribute on the USD Prim at the given path

Note

If the prim does not have the physics Rigid Body property added, calling this function will have no effect

Parameters
  • _value (Any) – Value to set physics:rigidBodyEnabled attribute to

  • prim_path (str) – The path to the USD Prim

Example:

>>> import omni.isaac.core.utils.physics as physics_utils
>>>
>>> physics_utils.set_rigid_body_enabled(False, "/World/Cube")
async simulate_async(seconds: float, steps_per_sec: int = 60, callback: Optional[Callable] = None) None

Helper function to simulate async for seconds * steps_per_sec frames.

Parameters
  • seconds (float) – time in seconds to simulate for

  • steps_per_sec (int, optional) – steps per second. Defaults to 60.

  • callback (Callable, optional) – optional function to run every step. Defaults to None.

Example:

>>> import asyncio
>>> import omni.isaac.core.utils.physics as physics_utils
>>> from omni.kit.async_engine import run_coroutine
>>>
>>> async def task():
...     # simulate 1 second with 120 steps per second
...     await physics_utils.simulate_async(1, steps_per_sec=120)
...
>>> run_coroutine(task())
>>> import asyncio
>>> import omni.isaac.core.utils.physics as physics_utils
>>> from omni.kit.async_engine import run_coroutine
>>>
>>> def callback(*args, **kwargs):
...     print("callback:", args, kwargs)
...
>>> async def task():
...     # simulate 1 second with 120 steps per second and call the callback on each step
...     await physics_utils.simulate_async(1, 120, callback)
...
>>> run_coroutine(task())

Prims Utils

create_prim(prim_path: str, prim_type: str = 'Xform', position: Optional[Sequence[float]] = None, translation: Optional[Sequence[float]] = None, orientation: Optional[Sequence[float]] = None, scale: Optional[Sequence[float]] = None, usd_path: Optional[str] = None, semantic_label: Optional[str] = None, semantic_type: str = 'class', attributes: Optional[dict] = None) pxr.Usd.Prim

Create a prim into current USD stage.

The method applies specified transforms, the semantic label and set specified attributes.

Parameters
  • prim_path (str) – The path of the new prim.

  • prim_type (str) – Prim type name

  • position (Sequence[float], optional) – prim position (applied last)

  • translation (Sequence[float], optional) – prim translation (applied last)

  • orientation (Sequence[float], optional) – prim rotation as quaternion

  • scale (np.ndarray (3), optional) – scaling factor in x, y, z.

  • usd_path (str, optional) – Path to the USD that this prim will reference.

  • semantic_label (str, optional) – Semantic label.

  • semantic_type (str, optional) – set to “class” unless otherwise specified.

  • attributes (dict, optional) – Key-value pairs of prim attributes to set.

Raises

Exception – If there is already a prim at the prim_path

Returns

The created USD prim.

Return type

Usd.Prim

Example:

>>> import numpy as np
>>> import omni.isaac.core.utils.prims as prims_utils
>>>
>>> # create a cube (/World/Cube) of size 2 centered at (1.0, 0.5, 0.0)
>>> prims_utils.create_prim(
...     prim_path="/World/Cube",
...     prim_type="Cube",
...     position=np.array([1.0, 0.5, 0.0]),
...     attributes={"size": 2.0}
... )
Usd.Prim(</World/Cube>)
>>> import omni.isaac.core.utils.prims as prims_utils
>>>
>>> # load an USD file (franka.usd) to the stage under the path /World/panda
>>> prims_utils.create_prim(
...     prim_path="/World/panda",
...     prim_type="Xform",
...     usd_path="/home/<user>/Documents/Assets/Robots/Franka/franka.usd"
... )
Usd.Prim(</World/panda>)
define_prim(prim_path: str, prim_type: str = 'Xform', fabric: bool = False) pxr.Usd.Prim

Create a USD Prim at the given prim_path of type prim_type unless one already exists

Note

This method will create a prim of the specified type in the specified path. To apply a transformation (position, orientation, scale), set attributes or load an USD file while creating the prim use the create_prim function.

Parameters
  • prim_path (str) – path of the prim in the stage

  • prim_type (str, optional) – The type of the prim to create. Defaults to “Xform”.

  • fabric (bool, optional) – True for fabric stage and False for USD stage. Defaults to False.

Raises

Exception – If there is already a prim at the prim_path

Returns

The created USD prim.

Return type

Usd.Prim

Example:

>>> import omni.isaac.core.utils.prims as prims_utils
>>>
>>> prims_utils.define_prim("/World/Shapes", prim_type="Xform")
Usd.Prim(</World/Shapes>)
delete_prim(prim_path: str) None

Remove the USD Prim and its descendants from the scene if able

Parameters

prim_path (str) – path of the prim in the stage

Example:

>>> import omni.isaac.core.utils.prims as prims_utils
>>>
>>> prims_utils.delete_prim("/World/Cube")
find_matching_prim_paths(prim_path_regex: str) List[str]

Find all the matching prim paths in the stage based on Regex expression.

Parameters

prim_path_regex (str) – The Regex expression for prim path.

Returns

List of prim paths that match input expression.

Return type

List[str]

Example:

>>> import omni.isaac.core.utils.prims as prims_utils
>>>
>>> # given the stage: /World/env/Cube, /World/env_01/Cube, /World/env_02/Cube
>>> # get only the prim Cube paths from env_01 and env_02
>>> prims_utils.find_matching_prim_paths("/World/env_.*/Cube")
['/World/env_01/Cube', '/World/env_02/Cube']
get_all_matching_child_prims(prim_path: str, predicate: typing.Callable[[str], bool] = <function <lambda>>, depth: typing.Optional[int] = None) List[pxr.Usd.Prim]

Performs a breadth-first search starting from the root and returns all the prims matching the predicate.

Parameters
  • prim_path (str) – root prim path to start traversal from.

  • predicate (Callable[[str], bool]) – predicate that checks the prim path of a prim and returns a boolean.

  • depth (Optional[int]) – maximum depth for traversal, should be bigger than zero if specified. Defaults to None (i.e: traversal till the end of the tree).

Returns

A list containing the root and children prims matching specified predicate.

Return type

List[Usd.Prim]

Example:

>>> import omni.isaac.core.utils.prims as prims_utils
>>>
>>> # get all hidden prims
>>> predicate = lambda path: prims_utils.is_prim_hidden_in_stage(path)  # True if the prim at path is hidden
>>> prims_utils.get_all_matching_child_prims("/", predicate)
[Usd.Prim(</OmniverseKit_Persp>),
 Usd.Prim(</OmniverseKit_Front>),
 Usd.Prim(</OmniverseKit_Top>),
 Usd.Prim(</OmniverseKit_Right>),
 Usd.Prim(</Render>)]
get_first_matching_child_prim(prim_path: str, predicate: Callable[[str], bool], fabric: bool = False) pxr.Usd.Prim

Recursively get the first USD Prim at the path string that passes the predicate function

Parameters
  • prim_path (str) – path of the prim in the stage

  • predicate (Callable[[str], bool]) – Function to test the prims against

  • fabric (bool, optional) – True for fabric stage and False for USD stage. Defaults to False.

Returns

The first prim or child of the prim, as defined by GetChildren, that passes the predicate

Return type

Usd.Prim

Example:

>>> import omni.isaac.core.utils.prims as prims_utils
>>>
>>> # given the stage: /World/Cube, /World/Cube_01, /World/Cube_02.
>>> # Get the first child prim of type Cube
>>> predicate = lambda path: prims_utils.get_prim_type_name(path) == "Cube"
>>> prims_utils.get_first_matching_child_prim("/", predicate)
Usd.Prim(</World/Cube>)
get_first_matching_parent_prim(prim_path: str, predicate: Callable[[str], bool]) pxr.Usd.Prim

Recursively get the first USD Prim at the parent path string that passes the predicate function

Parameters
  • prim_path (str) – path of the prim in the stage

  • predicate (Callable[[str], bool]) – Function to test the prims against

Returns

The first prim on the parent path, as defined by GetParent, that passes the predicate

Return type

str

Example:

>>> import omni.isaac.core.utils.prims as prims_utils
>>>
>>> # given the stage: /World/Cube. Get the first parent of Cube prim of type Xform
>>> predicate = lambda path: prims_utils.get_prim_type_name(path) == "Xform"
>>> prims_utils.get_first_matching_parent_prim("/World/Cube", predicate)
Usd.Prim(</World>)
get_prim_at_path(prim_path: str, fabric: bool = False) Union[pxr.Usd.Prim, usdrt.Usd._Usd.Prim]

Get the USD or Fabric Prim at a given path string

Parameters
  • prim_path (str) – path of the prim in the stage.

  • fabric (bool, optional) – True for fabric stage and False for USD stage. Defaults to False.

Returns

USD or Fabric Prim object at the given path in the current stage.

Return type

Union[Usd.Prim, usdrt.Usd._Usd.Prim]

Example:

>>> import omni.isaac.core.utils.prims as prims_utils
>>>
>>> prims_utils.get_prim_at_path("/World/Cube")
Usd.Prim(</World/Cube>)
get_prim_attribute_names(prim_path: str, fabric: bool = False) List[str]

Get all the attribute names of a prim at the path

Parameters
  • prim_path (str) – path of the prim in the stage

  • fabric (bool, optional) – True for fabric stage and False for USD stage. Defaults to False.

Raises

Exception – If there is not a valid prim at the given path

Returns

List of the prim attribute names

Return type

List[str]

Example:

>>> import omni.isaac.core.utils.prims as prims_utils
>>>
>>> prims_utils.get_prim_attribute_names("/World/Cube")
['doubleSided', 'extent', 'orientation', 'primvars:displayColor', 'primvars:displayOpacity',
 'purpose', 'size', 'visibility', 'xformOp:orient', 'xformOp:scale', 'xformOp:translate', 'xformOpOrder']
get_prim_attribute_value(prim_path: str, attribute_name: str, fabric: bool = False) Any

Get a prim attribute value

Parameters
  • prim_path (str) – path of the prim in the stage

  • attribute_name (str) – name of the attribute to get

  • fabric (bool, optional) – True for fabric stage and False for USD stage. Defaults to False.

Raises

Exception – If there is not a valid prim at the given path

Returns

Prim attribute value

Return type

Any

Example:

>>> import omni.isaac.core.utils.prims as prims_utils
>>>
>>> prims_utils.get_prim_attribute_value("/World/Cube", attribute_name="size")
1.0
get_prim_children(prim: pxr.Usd.Prim) List[pxr.Usd.Prim]

Return the call of the USD Prim’s GetChildren member function

Parameters

prim (Usd.Prim) – The parent USD Prim

Returns

A list of the prim’s children.

Return type

List[Usd.Prim]

Example:

>>> import omni.isaac.core.utils.prims as prims_utils
>>>
>>> # given the stage: /World/Cube, /World/Cube_01, /World/Cube_02.
>>> # Get all prims under the prim World
>>> prim = prims_utils.get_prim_at_path("/World")
>>> prims_utils.get_prim_children(prim)
[Usd.Prim(</World/Cube>), Usd.Prim(</World/Cube_01>), Usd.Prim(</World/Cube_02>)]
get_prim_object_type(prim_path: str) Optional[str]

Get the dynamic control object type of the USD Prim at the given path.

If the prim at the path is of Dynamic Control type e.g.: rigid_body, joint, dof, articulation, attractor, d6joint, then the corresponding string returned. If is an Xformable prim, then “xform” is returned. Otherwise None is returned.

Parameters

prim_path (str) – path of the prim in the stage

Raises

Exception – If the USD Prim is not a supported type.

Returns

String corresponding to the object type.

Return type

str

Example:

>>> import omni.isaac.core.utils.prims as prims_utils
>>>
>>> prims_utils.get_prim_object_type("/World/Cube")
xform
get_prim_parent(prim: pxr.Usd.Prim) pxr.Usd.Prim

Return the call of the USD Prim’s GetChildren member function

Parameters

prim (Usd.Prim) – The USD Prim to call GetParent on

Returns

The prim’s parent returned from GetParent

Return type

Usd.Prim

Example:

>>> import omni.isaac.core.utils.prims as prims_utils
>>>
>>> # given the stage: /World/Cube. Get the prim Cube's parent
>>> prim = prims_utils.get_prim_at_path("/World/Cube")
>>> prims_utils.get_prim_parent(prim)
Usd.Prim(</World>)
get_prim_path(prim: pxr.Usd.Prim) str

Get the path of a given USD prim.

Parameters

prim (Usd.Prim) – The input USD prim.

Returns

The path to the input prim.

Return type

str

Example:

>>> import omni.isaac.core.utils.prims as prims_utils
>>>
>>> prim = prims_utils.get_prim_at_path("/World/Cube")  # Usd.Prim(</World/Cube>)
>>> prims_utils.get_prim_path(prim)
/World/Cube
get_prim_property(prim_path: str, property_name: str) Any

Get the attribute of the USD Prim at the given path

Parameters
  • prim_path (str) – path of the prim in the stage

  • property_name (str) – name of the attribute to get

Returns

The attribute if it exists, None otherwise

Return type

Any

Example:

>>> import omni.isaac.core.utils.prims as prims_utils
>>>
>>> prims_utils.get_prim_property("/World/Cube", property_name="size")
1.0
get_prim_type_name(prim_path: str, fabric: bool = False) str

Get the TypeName of the USD Prim at the path if it is valid

Parameters
  • prim_path (str) – path of the prim in the stage

  • fabric (bool, optional) – True for fabric stage and False for USD stage. Defaults to False.

Raises

Exception – If there is not a valid prim at the given path

Returns

The TypeName of the USD Prim at the path string

Return type

str

Example:

>>> import omni.isaac.core.utils.prims as prims_utils
>>>
>>> prims_utils.get_prim_type_name("/World/Cube")
Cube
is_prim_ancestral(prim_path: str) bool

Check if any of the prims ancestors were brought in as a reference

Parameters

prim_path (str) – The path to the USD prim.

Returns

True if prim is part of a referenced prim, false otherwise.

Example:

>>> import omni.isaac.core.utils.prims as prims_utils
>>>
>>> # /World/Cube is a prim created
>>> prims_utils.is_prim_ancestral("/World/Cube")
False
>>> # /World/panda is an USD file loaded (as reference) under that path
>>> prims_utils.is_prim_ancestral("/World/panda")
False
>>> prims_utils.is_prim_ancestral("/World/panda/panda_link0")
True
is_prim_hidden_in_stage(prim_path: str) bool

Checks if the prim is hidden in the USd stage or not.

Warning

This function checks for the hide_in_stage_window prim metadata. This metadata is not related to the visibility of the prim.

Parameters

prim_path (str) – The path to the USD prim.

Returns

True if prim is hidden from stage window, False if not hidden.

Example:

>>> import omni.isaac.core.utils.prims as prims_utils
>>>
>>> # prim without the 'hide_in_stage_window' metadata
>>> prims_utils.is_prim_hidden_in_stage("/World/Cube")
None
>>> # prim with the 'hide_in_stage_window' metadata set to True
>>> prims_utils.is_prim_hidden_in_stage("/World/Cube")
True
is_prim_no_delete(prim_path: str) bool

Checks whether a prim can be deleted or not from USD stage.

Note

This function checks for the no_delete prim metadata. A prim with this metadata set to True cannot be deleted by using the edit menu, the context menu, or by calling the delete_prim function, for example.

Parameters

prim_path (str) – The path to the USD prim.

Returns

True if prim cannot be deleted, False if it can

Example:

>>> import omni.isaac.core.utils.prims as prims_utils
>>>
>>> # prim without the 'no_delete' metadata
>>> prims_utils.is_prim_no_delete("/World/Cube")
None
>>> # prim with the 'no_delete' metadata set to True
>>> prims_utils.is_prim_no_delete("/World/Cube")
True

Used to query if the prim_path corresponds to a link in an articulation which is a non root link.

Parameters

prim_path (str) – prim_path to query

Returns

True if the prim path corresponds to a link in an articulation which is a non root link

and can’t have a transformation applied to it.

Return type

bool

Example:

>>> import omni.isaac.core.utils.prims as prims_utils
>>>
>>> # /World/panda contains the prim tree for the Franka panda robot.
>>> # The prim on this path has the Physics Articulation Root property applied
>>> prims_utils.is_prim_non_root_articulation_link("/World/panda")
False
>>> prims_utils.is_prim_non_root_articulation_link("/World/panda/panda_link0")
True
is_prim_path_valid(prim_path: str, fabric: bool = False) bool

Check if a path has a valid USD Prim at it

Parameters
  • prim_path (str) – path of the prim in the stage

  • fabric (bool, optional) – True for fabric stage and False for USD stage. Defaults to False.

Returns

True if the path points to a valid prim

Return type

bool

Example:

>>> import omni.isaac.core.utils.prims as prims_utils
>>>
>>> # given the stage: /World/Cube
>>> prims_utils.is_prim_path_valid("/World/Cube")
True
>>> prims_utils.is_prim_path_valid("/World/Cube/")
False
>>> prims_utils.is_prim_path_valid("/World/Sphere")  # it doesn't exist
False
is_prim_root_path(prim_path: str) bool

Checks if the input prim path is root or not.

Parameters

prim_path (str) – The path to the USD prim.

Returns

True if the prim path is “/”, False otherwise

Example:

>>> import omni.isaac.core.utils.prims as prims_utils
>>>
>>> # given the stage: /World/Cube
>>> prims_utils.is_prim_root_path("/")
True
>>> prims_utils.is_prim_root_path("/World")
False
>>> prims_utils.is_prim_root_path("/World/Cube")
False
move_prim(path_from: str, path_to: str) None

Run the Move command to change a prims USD Path in the stage

Parameters
  • path_from (str) – Path of the USD Prim you wish to move

  • path_to (str) – Final destination of the prim

Example:

>>> import omni.isaac.core.utils.prims as prims_utils
>>>
>>> # given the stage: /World/Cube. Move the prim Cube outside the prim World
>>> prims_utils.move_prim("/World/Cube", "/Cube")
query_parent_path(prim_path: str, predicate: Callable[[str], bool]) bool

Check if one of the ancestors of the prim at the prim_path can pass the predicate

Parameters
  • prim_path (str) – path to the USD Prim for which to check the ancestors

  • predicate (Callable[[str], bool]) – The condition that must be True about the ancestors

Returns

True if there is an ancestor that can pass the predicate, False otherwise

Return type

bool

Example:

>>> import omni.isaac.core.utils.prims as prims_utils
>>>
>>> # given the stage: /World/Cube. Check is the prim Cube has an ancestor of type Xform
>>> predicate = lambda path: prims_utils.get_prim_type_name(path) == "Xform"
>>> prims_utils.query_parent_path("/World/Cube", predicate)
True
set_prim_attribute_value(prim_path: str, attribute_name: str, value: Any, fabric: bool = False)

Set a prim attribute value

Parameters
  • prim_path (str) – path of the prim in the stage

  • attribute_name (str) – name of the attribute to set

  • value (Any) – value to set the attribute to

  • fabric (bool, optional) – True for fabric stage and False for USD stage. Defaults to False.

Example:

>>> import omni.isaac.core.utils.prims as prims_utils
>>>
>>> # given the stage: /World/Cube. Set the Cube size to 5.0
>>> prims_utils.set_prim_attribute_value("/World/Cube", attribute_name="size", value=5.0)
set_prim_hide_in_stage_window(prim: pxr.Usd.Prim, hide: bool)

Set hide_in_stage_window metadata for a prim

Warning

This metadata is unrelated to the visibility of the prim. Use the set_prim_visibility function for the latter purpose

Parameters
  • prim (Usd.Prim) – Prim to set

  • hide (bool) – True to hide in stage window, false to show

Example:

>>> import omni.isaac.core.utils.prims as prims_utils
>>>
>>> prim = prims_utils.get_prim_at_path("/World/Cube")
>>> prims_utils.set_prim_hide_in_stage_window(prim, True)
set_prim_no_delete(prim: pxr.Usd.Prim, no_delete: bool)

Set no_delete metadata for a prim

Note

A prim with this metadata set to True cannot be deleted by using the edit menu, the context menu, or by calling the delete_prim function, for example.

Parameters
  • prim (Usd.Prim) – Prim to set

  • no_delete (bool) – True to make prim undeletable in stage window, false to allow deletion

Example:

>>> import omni.isaac.core.utils.prims as prims_utils
>>>
>>> prim = prims_utils.get_prim_at_path("/World/Cube")
>>> prims_utils.set_prim_no_delete(prim, True)
set_prim_property(prim_path: str, property_name: str, property_value: Any) None

Set the attribute of the USD Prim at the path

Parameters
  • prim_path (str) – path of the prim in the stage

  • property_name (str) – name of the attribute to set

  • property_value (Any) – value to set the attribute to

Example:

>>> import omni.isaac.core.utils.prims as prims_utils
>>>
>>> # given the stage: /World/Cube. Set the Cube size to 5.0
>>> prims_utils.set_prim_property("/World/Cube", property_name="size", property_value=5.0)
set_prim_visibility(prim: pxr.Usd.Prim, visible: bool) None

Sets the visibility of the prim in the opened stage.

Note

The method does this through the USD API.

Parameters
  • prim (Usd.Prim) – the USD prim

  • visible (bool) – flag to set the visibility of the usd prim in stage.

Example:

>>> import omni.isaac.core.utils.prims as prims_utils
>>>
>>> # given the stage: /World/Cube. Make the Cube not visible
>>> prim = prims_utils.get_prim_at_path("/World/Cube")
>>> prims_utils.set_prim_visibility(prim, False)
set_targets(prim: pxr.Usd.Prim, attribute: str, target_prim_paths: list)

Set targets for a prim relationship attribute

Parameters
  • prim (Usd.Prim) – Prim to create and set attribute on

  • attribute (str) – Relationship attribute to create

  • target_prim_paths (list) – list of targets to set

Example:

>>> import omni.isaac.core.utils.prims as prims_utils
>>>
>>> # given the stage: /World/Cube, /World/Cube_01, /World/Cube_02.
>>> # Set each prim Cube to the relationship targetPrim of the prim World
>>> prim = prims_utils.get_prim_at_path("/World")
>>> targets = ["/World/Cube", "/World/Cube_01", "/World/Cube_02"]
>>> prims_utils.set_targets(prim, "targetPrim", targets)

Random Utils

get_random_translation_from_camera(min_distance: float, max_distance: float, fov_x: float, fov_y: float, fraction_to_screen_edge: float) numpy.ndarray

Get a random translation from the camera, in the camera’s frame, that’s in view of the camera.

Parameters
  • min_distance (float) – minimum distance away from the camera (along the optical axis) of the random translation.

  • max_distance (float) – maximum distance away from the camera (along the optical axis) of the random translation.

  • fov_x (float) – field of view of the camera in the x-direction in radians.

  • fov_y (float) – field of view of the camera in the y-direction in radians.

  • fraction_to_screen_edge (float) – maximum allowed fraction to the edge of the screen the translated point may appear when viewed from the camera. A value of 0 corresponds to the translated point being centered in the camera’s view (on the optical axis), whereas a value of 1 corresponds to the translated point being on the edge of the screen in the camera’s view.

Returns

random translation from the camera, in the camera’s frame, that’s in view of the camera. Shape

is (3, ).

Return type

np.ndarray

get_random_values_in_range(min_range: numpy.ndarray, max_range: numpy.ndarray) numpy.ndarray

Get an array of random values where each element is between the corresponding min_range and max_range element.

Parameters
  • min_range (np.ndarray) – minimum values for each corresponding element of the array of random values. Shape is (num_values, ).

  • max_range (np.ndarray) – maximum values for each corresponding element of the array of random values. Shape is (num_values, ).

Returns

array of random values. Shape is (num_values, ).

Return type

np.ndarray

get_random_world_pose_in_view(camera_prim: pxr.Usd.Prim, min_distance: float, max_distance: float, fov_x: float, fov_y: float, fraction_to_screen_edge: float, coord_prim: pxr.Usd.Prim, min_rotation_range: numpy.ndarray, max_rotation_range: numpy.ndarray) Tuple[numpy.ndarray, numpy.ndarray]

Get a pose defined in the world frame that’s in view of the camera.

Parameters
  • camera_prim (Usd.Prim) – prim path of the camera.

  • min_distance (float) – minimum distance away from the camera (along the optical axis) of the random translation.

  • max_distance (float) – maximum distance away from the camera (along the optical axis) of the random translation.

  • fov_x (float) – field of view of the camera in the x-direction in radians.

  • fov_y (float) – field of view of the camera in the y-direction in radians.

  • fraction_to_screen_edge (float) – maximum allowed fraction to the edge of the screen the translated point may appear when viewed from the camera. A value of 0 corresponds to the translated point being centered in the camera’s view (on the optical axis), whereas a value of 1 corresponds to the translated point being on the edge of the screen in the camera’s view.

  • coord_prim (Usd.Prim) – prim whose frame the orientation is defined with respect to.

  • min_rotation_range (np.ndarray) – minimum XYZ Euler angles of the random pose, defined with respect to the frame of the prim at coord_prim. Shape is (3, ).

  • max_rotation_range (np.ndarray) – maximum XYZ Euler angles of the random pose, defined with respect to the frame of the prim at coord_prim.

Returns

first index is position in the world frame. Shape is (3, ). Second index is

quaternion orientation in the world frame. Quaternion is scalar-first (w, x, y, z). Shape is (4, ).

Return type

Tuple[np.ndarray, np.ndarray]

Render Product Utils

add_aov(render_product_path: str, aov_name: str)

Adds an AOV/Render Var to an existing render product

Parameters
  • render_product_path (str) – path to the render product prim

  • aov_name (str) – Name of the render var we want to add to this render product

Raises
  • RuntimeError – If the render product path is invalid

  • RuntimeError – If the renderVar could not be created

  • RuntimeError – If the renderVar could not be added to the render product

create_hydra_texture(resolution: Tuple[int], camera_prim_path: str)
get_camera_prim_path(render_product_path: str)

Get the current camera for a render product

Parameters

render_product_path (str) – path to the render product prim

Raises

RuntimeError – If the render product path is invalid

Returns

Path to the camera prim attached to this render product

Return type

str

get_resolution(render_product_path: str)

Get resolution for a render product

Parameters

render_product_path (str) – path to the render product prim

Raises

RuntimeError – If the render product path is invalid

Returns

(width,height)

Return type

Tuple[int]

set_camera_prim_path(render_product_path: str, camera_prim_path: str)

Sets the camera prim path for a render product

Parameters
  • render_product_path (str) – path to the render product prim

  • camera_prim_path (str) – path to the camera prim

Raises

RuntimeError – If the render product path is invalid

set_resolution(render_product_path: str, resolution: Tuple[int])

Set resolution for a render product

Parameters
  • render_product_path (str) – path to the render product prim

  • resolution (Tuple[float]) – width,height for render product

Raises

RuntimeError – If the render product path is invalid

Rotations Utils

euler_angles_to_quat(euler_angles: numpy.ndarray, degrees: bool = False, extrinsic: bool = True) numpy.ndarray

Convert Euler angles to quaternion.

Parameters
  • euler_angles (np.ndarray) – Euler XYZ angles.

  • degrees (bool, optional) – Whether input angles are in degrees. Defaults to False.

  • extrinsic (bool, optional) – True if the euler angles follows the extrinsic angles convention (equivalent to ZYX ordering but returned in the reverse) and False if it follows the intrinsic angles conventions (equivalent to XYZ ordering). Defaults to True.

Returns

quaternion (w, x, y, z).

Return type

np.ndarray

euler_to_rot_matrix(euler_angles: numpy.ndarray, degrees: bool = False, extrinsic: bool = True) numpy.ndarray

Convert Euler XYZ or ZYX angles to rotation matrix.

Parameters
  • euler_angles (np.ndarray) – Euler angles.

  • degrees (bool, optional) – Whether passed angles are in degrees.

  • extrinsic (bool, optional) – True if the euler angles follows the extrinsic angles convention (equivalent to ZYX ordering but returned in the reverse) and False if it follows the intrinsic angles conventions (equivalent to XYZ ordering). Defaults to True.

Returns

A 3x3 rotation matrix in its extrinsic or intrinsic form depends on the extrinsic argument.

Return type

np.ndarray

gf_quat_to_np_array(orientation: Union[pxr.Gf.Quatd, pxr.Gf.Quatf, pxr.Gf.Quaternion]) numpy.ndarray

Converts a pxr Quaternion type to a numpy array following [w, x, y, z] convention.

Parameters

orientation (Union[Gf.Quatd, Gf.Quatf, Gf.Quaternion]) – Input quaternion object.

Returns

A (4,) quaternion array in (w, x, y, z).

Return type

np.ndarray

gf_rotation_to_np_array(orientation: pxr.Gf.Rotation) numpy.ndarray

Converts a pxr Rotation type to a numpy array following [w, x, y, z] convention.

Parameters

orientation (Gf.Rotation) – Pxr rotation object.

Returns

A (4,) quaternion array in (w, x, y, z).

Return type

np.ndarray

lookat_to_quatf(camera: pxr.Gf.Vec3f, target: pxr.Gf.Vec3f, up: pxr.Gf.Vec3f) pxr.Gf.Quatf

[summary]

Parameters
  • camera (Gf.Vec3f) – [description]

  • target (Gf.Vec3f) – [description]

  • up (Gf.Vec3f) – [description]

Returns

Pxr quaternion object.

Return type

Gf.Quatf

matrix_to_euler_angles(mat: numpy.ndarray, degrees: bool = False, extrinsic: bool = True) numpy.ndarray

Convert rotation matrix to Euler XYZ extrinsic or intrinsic angles.

Parameters
  • mat (np.ndarray) – A 3x3 rotation matrix.

  • degrees (bool, optional) – Whether returned angles should be in degrees.

  • extrinsic (bool, optional) – True if the rotation matrix follows the extrinsic matrix convention (equivalent to ZYX ordering but returned in the reverse) and False if it follows the intrinsic matrix conventions (equivalent to XYZ ordering). Defaults to True.

Returns

Euler XYZ angles (intrinsic form) if extrinsic is False and Euler XYZ angles (extrinsic form) if extrinsic is True.

Return type

np.ndarray

quat_to_euler_angles(quat: numpy.ndarray, degrees: bool = False, extrinsic: bool = True) numpy.ndarray

Convert input quaternion to Euler XYZ or ZYX angles.

Parameters
  • quat (np.ndarray) – Input quaternion (w, x, y, z).

  • degrees (bool, optional) – Whether returned angles should be in degrees. Defaults to False.

  • extrinsic (bool, optional) – True if the euler angles follows the extrinsic angles convention (equivalent to ZYX ordering but returned in the reverse) and False if it follows the intrinsic angles conventions (equivalent to XYZ ordering). Defaults to True.

Returns

Euler XYZ angles (intrinsic form) if extrinsic is False and Euler XYZ angles (extrinsic form) if extrinsic is True.

Return type

np.ndarray

quat_to_rot_matrix(quat: numpy.ndarray) numpy.ndarray

Convert input quaternion to rotation matrix.

Parameters

quat (np.ndarray) – Input quaternion (w, x, y, z).

Returns

A 3x3 rotation matrix.

Return type

np.ndarray

rot_matrix_to_quat(mat: numpy.ndarray) numpy.ndarray

Convert rotation matrix to Quaternion.

Parameters

mat (np.ndarray) – A 3x3 rotation matrix.

Returns

quaternion (w, x, y, z).

Return type

np.ndarray

Semantics Utils

add_update_semantics(prim: pxr.Usd.Prim, semantic_label: str, type_label: str = 'class', suffix='') None

Apply a semantic label to a prim or update an existing label

Parameters
  • prim (Usd.Prim) – Usd Prim to add or update semantics on

  • semantic_label (str) – The label we want to apply

  • type_label (str) – The type of semantic information we are specifying (default = “class”)

  • suffix (str) – Additional suffix used to specify multiple semantic attribute names.

  • "Semantics" (By default the semantic attribute name is) –

  • additional (and to specify) –

  • used (attributes a suffix can be provided. Simple string concatenation is) – “Semantics” + suffix (default = “”)

get_semantics(prim: pxr.Usd.Prim) Dict[str, Tuple[str, str]]

Returns semantics that are applied to a prim

Parameters

prim (Usd.Prim) – Prim to return semantics for

Returns

Dictionary containing the name of the applied semantic, and the type and data associated with that semantic.

Return type

Dict[str, Tuple[str,str]]

remove_all_semantics(prim: pxr.Usd.Prim, recursive: bool = False) None

Removes all semantic tags from a given prim and its children

Parameters
  • prim (Usd.Prim) – Prim to remove any applied semantic APIs on

  • recursive (bool, optional) – Also traverse children and remove semantics recursively. Defaults to False.


Stage Utils

add_reference_to_stage(usd_path: str, prim_path: str, prim_type: str = 'Xform') pxr.Usd.Prim

Add USD reference to the opened stage at specified prim path.

Parameters
  • usd_path (str) – The path to USD file.

  • prim_path (str) – The prim path to attach reference.

  • prim_type (str, optional) – The type of prim. Defaults to “Xform”.

Raises

FileNotFoundError – When input USD file is found at specified path.

Returns

The USD prim at specified prim path.

Return type

Usd.Prim

Example:

>>> import omni.isaac.core.utils.stage as stage_utils
>>>
>>> # load an USD file (franka.usd) to the stage under the path /World/panda
>>> stage_utils.add_reference_to_stage(
...     usd_path="/home/<user>/Documents/Assets/Robots/Franka/franka.usd",
...     prim_path="/World/panda"
... )
Usd.Prim(</World/panda>)
clear_stage(predicate: Optional[Callable[[str], bool]] = None) None

Deletes all prims in the stage without populating the undo command buffer

Parameters

predicate (Optional[Callable[[str], bool]], optional) – user defined function that takes a prim_path (str) as input and returns True/False if the prim should/shouldn’t be deleted. If predicate is None, a default is used that deletes all prims

Example:

>>> import omni.isaac.core.utils.stage as stage_utils
>>>
>>> # clear the whole stage
>>> stage_utils.clear_stage()
>>>
>>> # given the stage: /World/Cube, /World/Cube_01, /World/Cube_02.
>>> # Delete only the prims of type Cube
>>> predicate = lambda path: prims_utils.get_prim_type_name(path) == "Cube"
>>> stage_utils.clear_stage(predicate)  # after the execution the stage will be /World
close_stage(callback_fn: Optional[Callable] = None) bool

Closes the current opened USD stage.

Note

Once the stage is closed, it is necessary to open a new stage or create a new one in order to work on it.

Parameters

callback_fn (Callable, optional) – Callback function to call while closing. Defaults to None.

Returns

True if operation is successful, otherwise false.

Return type

bool

Example:

>>> import omni.isaac.core.utils.stage as stage_utils
>>>
>>> stage_utils.close_stage()
True
>>> import omni.isaac.core.utils.stage as stage_utils
>>>
>>> def callback(*args, **kwargs):
...     print("callback:", args, kwargs)
...
>>> stage_utils.close_stage(callback)
True
>>> stage_utils.close_stage(callback)
callback: (False, 'Stage opening or closing already in progress!!') {}
False
create_new_stage() pxr.Usd.Stage

Create a new stage.

Returns

The created USD stage.

Return type

Usd.Stage

Example:

>>> import omni.isaac.core.utils.stage as stage_utils
>>>
>>> stage_utils.create_new_stage()
True
async create_new_stage_async() None

Create a new stage (asynchronous version).

Example:

>>> import asyncio
>>> import omni.isaac.core.utils.stage as stage_utils
>>> from omni.kit.async_engine import run_coroutine
>>>
>>> async def task():
...     await stage_utils.create_new_stage_async()
...
>>> run_coroutine(task())
get_current_stage(fabric: bool = False) Union[pxr.Usd.Stage, usdrt.Usd._Usd.Stage]

Get the current open USD or Fabric stage

Parameters

fabric (bool, optional) – True to get the fabric stage. False to get the USD stage. Defaults to False.

Returns

The USD or Fabric stage as specified by the input arg fabric.

Return type

Union[Usd.Stage, usdrt.Usd._Usd.Stage]

Example:

>>> import omni.isaac.core.utils.stage as stage_utils
>>>
>>> stage_utils.get_current_stage()
Usd.Stage.Open(rootLayer=Sdf.Find('anon:0x7fba6c04f840:World7.usd'),
                sessionLayer=Sdf.Find('anon:0x7fba6c01c5c0:World7-session.usda'),
                pathResolverContext=<invalid repr>)
get_next_free_path(path: str, parent: Optional[str] = None) str

Returns the next free usd path for the current stage

Parameters
  • path (str) – path we want to check

  • parent (str, optional) – Parent prim for the given path. Defaults to None.

Returns

a new path that is guaranteed to not exist on the current stage

Return type

str

Example:

>>> import omni.isaac.core.utils.stage as stage_utils
>>>
>>> # given the stage: /World/Cube, /World/Cube_01.
>>> # Get the next available path for /World/Cube
>>> stage_utils.get_next_free_path("/World/Cube")
/World/Cube_02
get_stage_units() float

Get the stage meters per unit currently set

The most common units and their values are listed in the following table:

Unit

Value

kilometer (km)

1000.0

meters (m)

1.0

inch (in)

0.0254

centimeters (cm)

0.01

millimeter (mm)

0.001

Returns

current stage meters per unit

Return type

float

Example:

>>> import omni.isaac.core.utils.stage as stage_utils
>>>
>>> stage_utils.get_stage_units()
1.0
get_stage_up_axis() str

Get the current up-axis of USD stage.

Returns

The up-axis of the stage.

Return type

str

Example:

>>> import omni.isaac.core.utils.stage as stage_utils
>>>
>>> stage_utils.get_stage_up_axis()
Z
is_stage_loading() bool

Convenience function to see if any files are being loaded.

Returns

True if loading, False otherwise

Return type

bool

Example:

>>> import omni.isaac.core.utils.stage as stage_utils
>>>
>>> stage_utils.is_stage_loading()
False
open_stage(usd_path: str) bool

Open the given usd file and replace currently opened stage.

Parameters

usd_path (str) – Path to the USD file to open.

Raises

ValueError – When input path is not a supported file type by USD.

Returns

True if operation is successful, otherwise false.

Return type

bool

Example:

>>> import omni.isaac.core.utils.stage as stage_utils
>>>
>>> stage_utils.open_stage("/home/<user>/Documents/Assets/Robots/Franka/franka.usd")
True
async open_stage_async(usd_path: str) Tuple[bool, int]

Open the given usd file and replace currently opened stage (asynchronous version).

Parameters

usd_path (str) – Path to the USD file to open.

Raises

ValueError – When input path is not a supported file type by USD.

Returns

True if operation is successful, otherwise false.

Return type

bool

Example:

>>> import asyncio
>>> import omni.isaac.core.utils.stage as stage_utils
>>> from omni.kit.async_engine import run_coroutine
>>>
>>> async def task():
...     await stage_utils.open_stage_async("/home/<user>/Documents/Assets/Robots/Franka/franka.usd")
...
>>> run_coroutine(task())
print_stage_prim_paths(fabric: bool = False) None

Traverses the stage and prints all prim (hidden or not) paths.

Example:

>>> import omni.isaac.core.utils.stage as stage_utils
>>>
>>> # given the stage: /World/Cube, /World/Cube_01, /World/Cube_02.
>>> stage_utils.print_stage_prim_paths()
/Render
/World
/World/Cube
/World/Cube_01
/World/Cube_02
/OmniverseKit_Persp
/OmniverseKit_Front
/OmniverseKit_Top
/OmniverseKit_Right
save_stage(usd_path: str, save_and_reload_in_place=True) bool

Save usd file to path, it will be overwritten with the current stage

Parameters
  • usd_path (str) – File path to save the current stage to

  • save_and_reload_in_place (bool, optional) – use save_as_stage to save and reload the root layer in place. Defaults to True.

Raises

ValueError – When input path is not a supported file type by USD.

Returns

True if operation is successful, otherwise false.

Return type

bool

Example:

>>> import omni.isaac.core.utils.stage as stage_utils
>>>
>>> stage_utils.save_stage("/home/<user>/Documents/Save/stage.usd")
True
set_livesync_stage(usd_path: str, enable: bool) bool

Save the stage and set the Live Sync mode for real-time live editing of shared files on a Nucleus server

Parameters
  • usd_path (str) – path to enable live sync for, it will be overwritten with the current stage

  • enable (bool) – True to enable livesync, false to disable livesync

Returns

True if operation is successful, otherwise false.

Return type

bool

Example:

>>> import omni.isaac.core.utils.stage as stage_utils
>>>
>>> stage_utils.set_livesync_stage("omniverse://localhost/Users/Live/stage.usd", enable=True)
server omniverse://localhost: ConnectionStatus.CONNECTING
server omniverse://localhost: ConnectionStatus.CONNECTED
True
set_stage_units(stage_units_in_meters: float) None

Set the stage meters per unit

The most common units and their values are listed in the following table:

Unit

Value

kilometer (km)

1000.0

meters (m)

1.0

inch (in)

0.0254

centimeters (cm)

0.01

millimeter (mm)

0.001

Parameters

stage_units_in_meters (float) – units for stage

Example:

>>> import omni.isaac.core.utils.stage as stage_utils
>>>
>>> stage_utils.set_stage_units(1.0)
set_stage_up_axis(axis: str = 'z') None

Change the up axis of the current stage

Parameters

axis (UsdGeom.Tokens, optional) – valid values are "x", "y" and "z"

Example:

>>> import omni.isaac.core.utils.stage as stage_utils
>>>
>>> # set stage up axis to Y-up
>>> stage_utils.set_stage_up_axis("y")
traverse_stage(fabric=False) Iterable

Traverse through prims (hidden or not) in the opened Usd stage.

Returns

Generator which yields prims from the stage in depth-first-traversal order.

Return type

Iterable

Example:

>>> import omni.isaac.core.utils.stage as stage_utils
>>>
>>> # given the stage: /World/Cube, /World/Cube_01, /World/Cube_02.
>>> # Traverse through prims in the stage
>>> for prim in stage_utils.traverse_stage():
>>>     print(prim)
Usd.Prim(</World>)
Usd.Prim(</World/Cube>)
Usd.Prim(</World/Cube_01>)
Usd.Prim(</World/Cube_02>)
Usd.Prim(</OmniverseKit_Persp>)
Usd.Prim(</OmniverseKit_Front>)
Usd.Prim(</OmniverseKit_Top>)
Usd.Prim(</OmniverseKit_Right>)
Usd.Prim(</Render>)
update_stage() None

Update the current USD stage.

Example:

>>> import omni.isaac.core.utils.stage as stage_utils
>>>
>>> stage_utils.update_stage()
async update_stage_async() None

Update the current USD stage (asynchronous version).

Example:

>>> import asyncio
>>> import omni.isaac.core.utils.stage as stage_utils
>>> from omni.kit.async_engine import run_coroutine
>>>
>>> async def task():
...     await stage_utils.update_stage_async()
...
>>> run_coroutine(task())

String Utils

find_root_prim_path_from_regex(prim_path_regex: str) Tuple[str, int]

Find the first prim above the regex pattern prim and its position.

Parameters

prim_path_regex (str) – full prim path including the regex pattern prim.

Returns

First position is the prim path to the parent of the regex prim.

Second position represents the level of the regex prim in the USD stage tree representation.

Return type

Tuple[str, int]

find_unique_string_name(initial_name: str, is_unique_fn: Callable[[str], bool]) str

Find a unique string name based on the predicate function provided.

The string is appended with “_N”, where N is a natural number till the resultant string is unique.

Parameters
  • initial_name (str) – The initial string name.

  • is_unique_fn (Callable[[str], bool]) – The predicate function to validate against.

Returns

A unique string based on input function.

Return type

str

Transformations Utils

get_relative_transform(source_prim: pxr.Usd.Prim, target_prim: pxr.Usd.Prim) numpy.ndarray

Get the relative transformation matrix from the source prim to the target prim.

Parameters
  • source_prim (Usd.Prim) – source prim from which frame to compute the relative transform.

  • target_prim (Usd.Prim) – target prim to which frame to compute the relative transform.

Returns

Column-major transformation matrix with shape (4, 4).

Return type

np.ndarray

get_transform_with_normalized_rotation(transform: numpy.ndarray) numpy.ndarray

Get the transform after normalizing rotation component.

Parameters

transform (np.ndarray) – transformation matrix with shape (4, 4).

Returns

transformation matrix with normalized rotation with shape (4, 4).

Return type

np.ndarray

get_translation_from_target(translation_from_source: numpy.ndarray, source_prim: pxr.Usd.Prim, target_prim: pxr.Usd.Prim) numpy.ndarray

Get a translation with respect to the target’s frame, from a translation in the source’s frame.

Parameters
  • translation_from_source (np.ndarray) – translation from the frame of the prim at source_path. Shape is (3, ).

  • source_prim (Usd.Prim) – prim path of the prim whose frame the original/untransformed translation (translation_from_source) is defined with respect to.

  • target_prim (Usd.Prim) – prim path of the prim whose frame corresponds to the target frame that the returned translation will be defined with respect to.

Returns

translation with respect to the target’s frame. Shape is (3, ).

Return type

np.ndarray

get_world_pose_from_relative(coord_prim: pxr.Usd.Prim, relative_translation: numpy.ndarray, relative_orientation: numpy.ndarray) Tuple[numpy.ndarray, numpy.ndarray]

Get a pose defined in the world frame from a pose defined relative to the frame of the coord_prim.

Parameters
  • coord_prim (Usd.Prim) – path of the prim whose frame the relative pose is defined with respect to.

  • relative_translation (np.ndarray) – translation relative to the frame of the prim at prim_path. Shape is (3, ).

  • relative_orientation (np.ndarray) – quaternion orientation relative to the frame of the prim at prim_path. Quaternion is scalar-first (w, x, y, z). Shape is (4, ).

Returns

first index is position in the world frame. Shape is (3, ). Second index is

quaternion orientation in the world frame. Quaternion is scalar-first (w, x, y, z). Shape is (4, ).

Return type

Tuple[np.ndarray, np.ndarray]

pose_from_tf_matrix(transformation: numpy.ndarray) Tuple[numpy.ndarray, numpy.ndarray]

Gets pose corresponding to input transformation matrix.

Parameters

transformation (np.ndarray) – Column-major transformation matrix. shape is (4, 4).

Returns

first index is translation corresponding to transformation. shape is (3, ).

second index is quaternion orientation corresponding to transformation. quaternion is scalar-first (w, x, y, z). shape is (4, ).

Return type

Tuple[np.ndarray, np.ndarray]

tf_matrices_from_poses(translations: Union[numpy.ndarray, torch.Tensor], orientations: Union[numpy.ndarray, torch.Tensor]) Union[numpy.ndarray, torch.Tensor]

[summary]

Parameters
  • translations (Union[np.ndarray, torch.Tensor]) – translations with shape (N, 3).

  • orientations (Union[np.ndarray, torch.Tensor]) – quaternion representation (scalar first) with shape (N, 4).

Returns

transformation matrices with shape (N, 4, 4)

Return type

Union[np.ndarray, torch.Tensor]

tf_matrix_from_pose(translation: Sequence[float], orientation: Sequence[float]) numpy.ndarray

Compute input pose to transformation matrix.

Parameters
  • pos (Sequence[float]) – The translation vector.

  • rot (Sequence[float]) – The orientation quaternion.

Returns

A 4x4 matrix.

Return type

np.ndarray

Types Utils

class ArticulationAction(joint_positions: Optional[Union[List, numpy.ndarray]] = None, joint_velocities: Optional[Union[List, numpy.ndarray]] = None, joint_efforts: Optional[Union[List, numpy.ndarray]] = None, joint_indices: Optional[Union[List, numpy.ndarray]] = None)

[summary]

Parameters
  • joint_positions (Optional[Union[List, np.ndarray]], optional) – [description]. Defaults to None.

  • joint_velocities (Optional[Union[List, np.ndarray]], optional) – [description]. Defaults to None.

  • joint_efforts (Optional[Union[List, np.ndarray]], optional) – [description]. Defaults to None.

get_dict() dict

[summary]

Returns

[description]

Return type

dict

get_dof_action(index: int) dict

[summary]

Parameters

index (int) – [description]

Returns

[description]

Return type

dict

get_length() Optional[int]

[summary]

Returns

[description]

Return type

Optional[int]

class ArticulationActions(joint_positions: Optional[Union[List, numpy.ndarray]] = None, joint_velocities: Optional[Union[List, numpy.ndarray]] = None, joint_efforts: Optional[Union[List, numpy.ndarray]] = None, joint_indices: Optional[Union[List, numpy.ndarray]] = None)

[summary]

Parameters
  • joint_positions (Optional[Union[List, np.ndarray]], optional) – [description]. Defaults to None.

  • joint_velocities (Optional[Union[List, np.ndarray]], optional) – [description]. Defaults to None.

  • joint_efforts (Optional[Union[List, np.ndarray]], optional) – [description]. Defaults to None.

class DOFInfo(prim_path: str, handle: int, prim: pxr.Usd.Prim, index: int)

[summary]

Parameters
  • prim_path (str) – [description]

  • handle (int) – [description]

  • prim (Usd.Prim) – [description]

  • index (int) – [description]

class DataFrame(current_time_step: int, current_time: float, data: dict)

[summary]

Parameters
  • current_time_step (int) – [description]

  • current_time (float) – [description]

  • data (dict) – [description]

get_dict() dict

[summary]

Returns

[description]

Return type

dict

classmethod init_from_dict(dict_representation: dict)

[summary]

Parameters

dict_representation (dict) – [description]

Returns

[description]

Return type

DataFrame

class DynamicState(position: numpy.ndarray, orientation: numpy.ndarray, linear_velocity: numpy.ndarray, angular_velocity: numpy.ndarray)

[summary]

Parameters
  • position (np.ndarray) – [description]

  • orientation (np.ndarray) – [description]

class DynamicsViewState(positions: Union[numpy.ndarray, torch.Tensor], orientations: Union[numpy.ndarray, torch.Tensor], linear_velocities: Union[numpy.ndarray, torch.Tensor], angular_velocities: Union[numpy.ndarray, torch.Tensor])

[summary]

Parameters
  • position (np.ndarray) – [description]

  • orientation (np.ndarray) – [description]

class JointsState(positions: numpy.ndarray, velocities: numpy.ndarray, efforts: numpy.ndarray)

[summary]

Parameters
  • positions (np.ndarray) – [description]

  • velocities (np.ndarray) – [description]

  • efforts (np.ndarray) – [description]

class XFormPrimState(position: numpy.ndarray, orientation: numpy.ndarray)

[summary]

Parameters
  • position (np.ndarray) – [description]

  • orientation (np.ndarray) – [description]

class XFormPrimViewState(positions: Union[numpy.ndarray, torch.Tensor], orientations: Union[numpy.ndarray, torch.Tensor])

[summary]

Parameters
  • positions (Union[np.ndarray, torch.Tensor]) – positions with shape of (N, 3).

  • orientations (Union[np.ndarray, torch.Tensor]) – quaternion representation of orientation (scalar first) with shape (N, 4).

Viewports Utils

add_aov_to_viewport(viewport_api, aov_name: str)
backproject_depth(depth_image: numpy.array, viewport_api: Any, max_clip_depth: float) numpy.array

Backproject depth image to image space

Parameters
  • depth_image (np.array) – Depth image buffer

  • viewport_api (Any) – Handle to viewport api

  • max_clip_depth (float) – Depth values larger than this will be clipped

Returns

[description]

Return type

np.array

create_viewport_for_camera(viewport_name: str, camera_prim_path: str, width: int = 1280, height: int = 720, position_x: int = 0, position_y: int = 0)

Create a new viewport and peg it to a specific camera specified by camera_prim_path. If the viewport already exists with the specified viewport_name, that viewport will be replaced with the new camera view.

Parameters
  • viewport_name (str) – name of the viewport. If not provided, it will default to camera name.

  • camera_prim_path (str) – name of the prim path of the camera

  • width (int) – width of the viewport window, in pixels.

  • height (int) – height of the viewport window, in pixels.

  • position_x (int) – location x of the viewport window.

  • position_y (int) – location y of the viewport window.

destroy_all_viewports(usd_context_name: Optional[str] = None, destroy_main_viewport=True)

Destroys all viewport windows

Parameters
  • usd_context_name (str, optional) – usd context to use. Defaults to None.

  • destroy_main_viewport (bool, optional) – set to true to not destroy the default viewport. Defaults to False.

get_id_from_index(index)

Get the viewport id for a given index. This function was added for backwards compatibility for VP2 as viewport IDs are not the same as the viewport index

Parameters

index (_type_) – viewport index to retrieve ID for

Returns

Returns None if window index was not found

Return type

viewport id

get_intrinsics_matrix(viewport_api: Any) numpy.ndarray

Get intrinsic matrix for the camera attached to a specific viewport

Parameters

viewport (Any) – Handle to viewport api

Returns

the intrinsic matrix associated with the specified viewport
The following image convention is assumed:

+x should point to the right in the image +y should point down in the image

Return type

np.ndarray

get_viewport_names(usd_context_name: Optional[str] = None) List[str]

Get list of all viewport names

Parameters

usd_context_name (str, optional) – usd context to use. Defaults to None.

Returns

List of viewport names

Return type

List[str]

get_window_from_id(id, usd_context_name: Optional[str] = None)

Find window that matches a given viewport id

Parameters
  • id (_type_) – Viewport ID to get window for

  • usd_context_name (str, optional) – usd context to use. Defaults to None.

Returns

Returns None if window with matching ID was not found

Return type

Window

project_depth_to_worldspace(depth_image: numpy.array, viewport_api: Any, max_clip_depth: float) List[carb._carb.Float3]

Project depth image to world space

Parameters
  • depth_image (np.array) – Depth image buffer

  • viewport_api (Any) – Handle to viewport api

  • max_clip_depth (float) – Depth values larger than this will be clipped

Returns

List of points from depth in world space

Return type

List[carb.Float3]

set_camera_view(eye: numpy.array, target: numpy.array, camera_prim_path: str = '/OmniverseKit_Persp', viewport_api=None) None

Set the location and target for a camera prim in the stage given its path

Parameters
  • eye (np.ndarray) – Location of camera.

  • target (np.ndarray,) – Location of camera target.

  • camera_prim_path (str, optional) – Path to camera prim being set. Defaults to “/OmniverseKit_Persp”.

set_intrinsics_matrix(viewport_api: Any, intrinsics_matrix: numpy.ndarray, focal_length: float = 1.0) None

Set intrinsic matrix for the camera attached to a specific viewport

Note

We assume cx and cy are centered in the camera horizontal_aperture_offset and vertical_aperture_offset are computed and set on the camera prim but are not used

Parameters
  • viewport (Any) – Handle to viewport api

  • intrinsics_matrix (np.ndarray) – A 3x3 intrinsic matrix

  • focal_length (float, optional) – Default focal length to use when computing aperture values. Defaults to 1.0.

Raises
  • ValueError – If intrinsic matrix is not a 3x3 matrix.

  • ValueError – If camera prim is not valid

XForms Utils

clear_xform_ops(prim: pxr.Usd.Prim)

Remove all xform ops from input prim.

Parameters

prim (Usd.Prim) – The input USD prim.

get_local_pose(prim_path)
get_world_pose(prim_path)
reset_and_set_xform_ops(prim: pxr.Usd.Prim, translation: pxr.Gf.Vec3d, orientation: pxr.Gf.Quatd, scale: pxr.Gf.Vec3d = Gf.Vec3d(1.0, 1.0, 1.0))

Reset xform ops to isaac sim defaults, and set their values

Parameters
  • prim (Usd.Prim) – Prim to reset

  • translation (Gf.Vec3d) – translation to set

  • orientation (Gf.Quatd) – orientation to set

  • scale (Gf.Vec3d, optional) – scale to set. Defaults to Gf.Vec3d([1.0, 1.0, 1.0]).

reset_xform_ops(prim: pxr.Usd.Prim)

Reset xform ops for a prim to isaac sim defaults,

Parameters

prim (Usd.Prim) – Prim to reset xform ops on

Numpy Utils

Rotations

deg2rad(degree_value: numpy.ndarray, device=None) numpy.ndarray

_summary_

Parameters
  • degree_value (np.ndarray) – _description_

  • device (_type_, optional) – _description_. Defaults to None.

Returns

_description_

Return type

np.ndarray

euler_angles_to_quats(euler_angles: numpy.ndarray, degrees: bool = False, extrinsic: bool = True, device=None) numpy.ndarray

Vectorized version of converting euler angles to quaternion (scalar first)

Parameters
  • np.ndarray (euler_angles) – euler angles with shape (N, 3) or (3,) representation XYZ in extrinsic coordinates

  • extrinsic (bool, optional) – True if the euler angles follows the extrinsic angles convention (equivalent to ZYX ordering but returned in the reverse) and False if it follows the intrinsic angles conventions (equivalent to XYZ ordering). Defaults to True.

  • degrees (bool, optional) – True if degrees, False if radians. Defaults to False.

Returns

quaternions representation of the angles (N, 4) or (4,) - scalar first.

Return type

np.ndarray

gf_quat_to_tensor(orientation: Union[pxr.Gf.Quatd, pxr.Gf.Quatf, pxr.Gf.Quaternion], device=None) numpy.ndarray

Converts a pxr Quaternion type to a numpy array following [w, x, y, z] convention.

Parameters

orientation (Union[Gf.Quatd, Gf.Quatf, Gf.Quaternion]) – [description]

Returns

[description]

Return type

np.ndarray

quats_to_euler_angles(quaternions: numpy.ndarray, degrees: bool = False, extrinsic: bool = True, device=None) numpy.ndarray

Vectorized version of converting quaternions (scalar first) to euler angles

Parameters
  • quaternions (np.ndarray) – quaternions with shape (N, 4) or (4,) - scalar first

  • degrees (bool, optional) – Return euler angles in degrees if True, radians if False. Defaults to False.

  • extrinsic (bool, optional) – True if the euler angles follows the extrinsic angles convention (equivalent to ZYX ordering but returned in the reverse) and False if it follows the intrinsic angles conventions (equivalent to XYZ ordering). Defaults to True.

Returns

Euler angles in extrinsic or intrinsic coordinates XYZ order with shape (N, 3) or (3,) corresponding to the quaternion rotations

Return type

np.ndarray

quats_to_rot_matrices(quaternions: numpy.ndarray, device=None) numpy.ndarray

Vectorized version of converting quaternions to rotation matrices

Parameters

quaternions (np.ndarray) – quaternions with shape (N, 4) or (4,) and scalar first

Returns

N Rotation matrices with shape (N, 3, 3) or (3, 3)

Return type

np.ndarray

quats_to_rotvecs(quaternions: numpy.ndarray, device=None) numpy.ndarray

Vectorized version of converting quaternions to rotation vectors

Parameters

quaternions (np.ndarray) – quaternions with shape (N, 4) or (4,) and scalar first

Returns

N rotation vectors with shape (N,3) or (3,). The magnitude of the rotation vector describes the magnitude of the rotation.

The normalized rotation vector represents the axis of rotation.

Return type

np.ndarray

rad2deg(radian_value: numpy.ndarray, device=None) numpy.ndarray

_summary_

Parameters
  • radian_value (np.ndarray) – _description_

  • device (_type_, optional) – _description_. Defaults to None.

Returns

_description_

Return type

np.ndarray

rot_matrices_to_quats(rotation_matrices: numpy.ndarray, device=None) numpy.ndarray

Vectorized version of converting rotation matrices to quaternions

Parameters

rotation_matrices (np.ndarray) – N Rotation matrices with shape (N, 3, 3) or (3, 3)

Returns

quaternion representation of the rotation matrices (N, 4) or (4,) - scalar first

Return type

np.ndarray

rotvecs_to_quats(rotation_vectors: numpy.ndarray, degrees: bool = False, device=None) numpy.ndarray

Vectorized version of converting rotation vectors to quaternions

Parameters
  • rotation_vectors (np.ndarray) – N rotation vectors with shape (N, 3) or (3,). The magnitude of the rotation vector describes the magnitude of the rotation. The normalized rotation vector represents the axis of rotation.

  • degrees (bool) – The magnitude of the rotation vector will be interpreted as degrees if True, and radians if False. Defaults to False.

Returns

quaternion representation of the rotation matrices (N, 4) or (4,) - scalar first

Return type

np.ndarray

wxyz2xyzw(q, ret_torch=False)
xyzw2wxyz(q, ret_torch=False)

Maths

cos(data)
inverse(data)
matmul(matrix_a, matrix_b)
sin(data)
transpose_2d(data)

Tensor

as_type(data, dtype)
assign(src, dst, indices)
clone_tensor(data, device=None)
convert(data, device=None, dtype='float32', indexed=None)
create_tensor_from_list(data, dtype, device=None)
create_zeros_tensor(shape, dtype, device=None)
expand_dims(data, axis)
move_data(data, device=None)
pad(data, pad_width, mode='constant', value=None)
resolve_indices(indices, count, device=None)
tensor_cat(data, device=None, dim=- 1)
tensor_stack(data, dim=0)
to_list(data)
to_numpy(data)

Transformations

assign_pose(current_positions, current_orientations, positions, orientations, indices, device=None, pose=None)
get_local_from_world(parent_transforms, positions, orientations, device=None)
get_pose(positions, orientations, device=None)
get_world_from_local(parent_transforms, translations, orientations, device=None)
tf_matrices_from_poses(translations: numpy.ndarray, orientations: numpy.ndarray, device=None) numpy.ndarray

[summary]

Parameters
  • translations (Union[np.ndarray, torch.Tensor]) – translations with shape (N, 3).

  • orientations (Union[np.ndarray, torch.Tensor]) – quaternion representation (scalar first) with shape (N, 4).

Returns

transformation matrices with shape (N, 4, 4)

Return type

Union[np.ndarray, torch.Tensor]

Torch Utils

Rotations

deg2rad(degree_value: float, device=None) torch.Tensor

_summary_

Parameters
  • degree_value (torch.Tensor) – _description_

  • device (_type_, optional) – _description_. Defaults to None.

Returns

_description_

Return type

torch.Tensor

euler_angles_to_quats(euler_angles: torch.Tensor, degrees: bool = False, extrinsic: bool = True, device=None) torch.Tensor

Vectorized version of converting euler angles to quaternion (scalar first)

Parameters
  • euler_angles (Union[np.ndarray, torch.Tensor]) – euler angles with shape (N, 3)

  • degrees (bool, optional) – True if degrees, False if radians. Defaults to False.

  • extrinsic (bool, optional) – True if the euler angles follows the extrinsic angles convention (equivalent to ZYX ordering but returned in the reverse) and False if it follows the intrinsic angles conventions (equivalent to XYZ ordering). Defaults to True.

Returns

quaternions representation of the angles (N, 4) - scalar first.

Return type

Union[np.ndarray, torch.Tensor]

gf_quat_to_tensor(orientation: Union[pxr.Gf.Quatd, pxr.Gf.Quatf, pxr.Gf.Quaternion], device=None) torch.Tensor

Converts a pxr Quaternion type to a torch array (scalar first).

Parameters

orientation (Union[Gf.Quatd, Gf.Quatf, Gf.Quaternion]) – [description]

Returns

[description]

Return type

torch.Tensor

normalise_quat_in_pose(pose)

Takes a pose and normalises the quaternion portion of it.

Parameters

pose – shape N, 7

Returns

Pose with normalised quat. Shape N, 7

rad2deg(radian_value: torch.Tensor, device=None) torch.Tensor

_summary_

Parameters
  • radian_value (torch.Tensor) – _description_

  • device (_type_, optional) – _description_. Defaults to None.

Returns

_description_

Return type

torch.Tensor

rot_matrices_to_quats(rotation_matrices: torch.Tensor, device=None) torch.Tensor

Vectorized version of converting rotation matrices to quaternions

Parameters

rotation_matrices (torch.Tensor) – N Rotation matrices with shape (N, 3, 3) or (3, 3)

Returns

quaternion representation of the rotation matrices (N, 4) or (4,) - scalar first

Return type

torch.Tensor

wxyz2xyzw(q)
xyzw2wxyz(q)

Maths

cos(data)
inverse(data)
matmul(matrix_a, matrix_b)
set_seed(seed, torch_deterministic=False)

set seed across modules

sin(data)
transpose_2d(data)
unscale_np(x, lower, upper)

Tensor

as_type(data, dtype)
assign(src, dst, indices)
clone_tensor(data, device)
convert(data, device, dtype='float32', indexed=None)
create_tensor_from_list(data, dtype, device=None)
create_zeros_tensor(shape, dtype, device=None)
expand_dims(data, axis)
move_data(data, device)
pad(data, pad_width, mode='constant', value=None)
resolve_indices(indices, count, device)
tensor_cat(data, device=None, dim=- 1)
tensor_stack(data, dim=0)
to_list(data)
to_numpy(data)

Transformations

assign_pose(current_positions, current_orientations, positions, orientations, indices, device, pose=None)
get_local_from_world(parent_transforms, positions, orientations, device)
get_pose(positions, orientations, device)
get_world_from_local(parent_transforms, translations, orientations, device)
normalise_quat_in_pose(pose)

Takes a pose and normalises the quaternion portion of it.

Parameters

pose – shape N, 7

Returns

Pose with normalised quat. Shape N, 7

tf_matrices_from_poses(translations: torch.Tensor, orientations: torch.Tensor, device=None) torch.Tensor

[summary]

Parameters
  • translations (Union[np.ndarray, torch.Tensor]) – translations with shape (N, 3).

  • orientations (Union[np.ndarray, torch.Tensor]) – quaternion representation (scalar first) with shape (N, 4).

Returns

transformation matrices with shape (N, 4, 4)

Return type

Union[np.ndarray, torch.Tensor]

Warp Utils

Rotations

deg2rad(degree_value: float, device=None) torch.Tensor

_summary_

Parameters
  • degree_value (torch.Tensor) – _description_

  • device (_type_, optional) – _description_. Defaults to None.

Returns

_description_

Return type

torch.Tensor

euler_angles_to_quats(euler_angles: torch.Tensor, degrees: bool = False, extrinsic: bool = True, device=None) torch.Tensor

Vectorized version of converting euler angles to quaternion (scalar first)

Parameters
  • euler_angles (Union[np.ndarray, torch.Tensor]) – euler angles with shape (N, 3)

  • degrees (bool, optional) – True if degrees, False if radians. Defaults to False.

  • extrinsic (bool, optional) – True if the euler angles follows the extrinsic angles convention (equivalent to ZYX ordering but returned in the reverse) and False if it follows the intrinsic angles conventions (equivalent to XYZ ordering). Defaults to True.

Returns

quaternions representation of the angles (N, 4) - scalar first.

Return type

Union[np.ndarray, torch.Tensor]

gf_quat_to_tensor(orientation: Union[pxr.Gf.Quatd, pxr.Gf.Quatf, pxr.Gf.Quaternion], device=None) torch.Tensor

Converts a pxr Quaternion type to a torch array (scalar first).

Parameters

orientation (Union[Gf.Quatd, Gf.Quatf, Gf.Quaternion]) – [description]

Returns

[description]

Return type

torch.Tensor

normalise_quat_in_pose(pose)

Takes a pose and normalises the quaternion portion of it.

Parameters

pose – shape N, 7

Returns

Pose with normalised quat. Shape N, 7

rad2deg(radian_value: torch.Tensor, device=None) torch.Tensor

_summary_

Parameters
  • radian_value (torch.Tensor) – _description_

  • device (_type_, optional) – _description_. Defaults to None.

Returns

_description_

Return type

torch.Tensor

rot_matrices_to_quats(rotation_matrices: torch.Tensor, device=None) torch.Tensor

Vectorized version of converting rotation matrices to quaternions

Parameters

rotation_matrices (torch.Tensor) – N Rotation matrices with shape (N, 3, 3) or (3, 3)

Returns

quaternion representation of the rotation matrices (N, 4) or (4,) - scalar first

Return type

torch.Tensor

wxyz2xyzw(q)
xyzw2wxyz(q)

Tensor

as_type(data, dtype)
assign(src, dst, indices)
clone_tensor(data, device)
convert(data, device, dtype='float32', indexed=None)
create_tensor_from_list(data, dtype, device=None)
create_zeros_tensor(shape, dtype, device=None)
expand_dims(data, axis)
move_data(data, device)
pad(data, pad_width, mode='constant', value=None)
resolve_indices(indices, count, device)
tensor_cat(data, device=None, dim=- 1)
tensor_stack(data, dim=0)
to_list(data)
to_numpy(data)

Transformations

assign_pose(current_positions, current_orientations, positions, orientations, indices, device, pose=None)
get_local_from_world(parent_transforms, positions, orientations, device)
get_pose(positions, orientations, device)
get_world_from_local(parent_transforms, translations, orientations, device)
normalise_quat_in_pose(pose)

Takes a pose and normalises the quaternion portion of it.

Parameters

pose – shape N, 7

Returns

Pose with normalised quat. Shape N, 7

tf_matrices_from_poses(translations: torch.Tensor, orientations: torch.Tensor, device=None) torch.Tensor

[summary]

Parameters
  • translations (Union[np.ndarray, torch.Tensor]) – translations with shape (N, 3).

  • orientations (Union[np.ndarray, torch.Tensor]) – quaternion representation (scalar first) with shape (N, 4).

Returns

transformation matrices with shape (N, 4, 4)

Return type

Union[np.ndarray, torch.Tensor]