1. Environment Setup¶
Omniverse Isaac Sim is built on NVIDIA Omniverse using tools provided in Omniverse Kit. Omniverse Kit comes with a default UI that allows the user to edit an USD stage with ease. In this tutorial series, we will go over the basic steps of setting up environment, adding and editing simple objects and their properties on a USD stage, rigging rigid bodies with joints and articulations, and adding cameras and sensors. At the end of the series, you should have the basic skill to navigate Omniverse Isaac Sim, become familiar with frequently used terms, and be able to build an environment and setup your robots via the graphical interface.
1.1. Learning Objectives¶
This tutorial details how to build a physics-enabled virtual world using the tools provided in the Omniverse Isaac Sim GUI. We will cover how to setup
General physics properties
1.2. Getting Started¶
Please review the Isaac Sim Interface tutorial prior to beginning this tutorial.
Let’s start with the clean stage provided at the opening of Omniverse Isaac Sim. If you have already added objects to your stage, go to File menu and click on New. The stage provided to you has a default
World Xform, and a
defaultLight. Both can be found on the stage tree on the left under the Stage tag.
1.3. Creating the Physics Scene¶
We will start by adding a Physics Scene to provide the general physics simulation properties to the world, such as gravity and physics time steps. Go to the Menu Bar and click Create > Physics > Physics Scene. A PhysicsScene should be added to the stage tree. Click on it to examine its properties. You can see that gravity is set to point at the -Z direction with a unit of 980, a reminder that the default unit of length is centimeters.
Unless you are simulating hundreds of rigid bodies and robots, it is more efficient to use a CPU solver instead of GPU, so for the purpose of this tutorial, disable GPU dynamics and use MBP Broadphase inside the Physics Scene’s Property tab.
1.4. Adding a Ground Plane¶
Next we will add a ground plane to the virtual environment. The ground plane will prevent any physics-enabled objects from falling below it. Go to the top Menu Bar and Click Create > Physics > Ground Plane. The ground plane’s collision property extends indefinitely even though the plane is only visible up to 25m in each direction. Turn on the grid to make the ground plane easier to see.
Every new Stage is pre-populated with a
defaultLight — otherwise you wouldn’t see anything. But let’s create an additional spotlight as an exercise.
Go to Create > Light > Sphere Light.
Move it up and turn it face down by moving it 700 units up and void the rotation in X and Y axis.
Inside the Property Tab, change its color in Main > Color by simply clicking on the color bar and pick a color of your choice.
Change its intensity Main > Intensity to 1e6; Limit the scope of the spot in Shaping -> cone:angle to 45 degrees, and soften the edge of the spotlight in Shaping -> cone:softness to 0.05.
To make the new spotlight easier to see, we will reduce the intensity of the default light by going to its Property tab and set Main > Intensity to 300.
This tutorial begins the series of steps to create a virtual world suitable for physics simulation and testing Omniverse Isaac Sim. The following topics were covered:
Adding a ground plane, lighting, and physics scene.
1.6.1. Next Steps¶
Continue on to Simple Objects to learn how to add simple objects to Omniverse Isaac Sim and edit their properties.