Physics#

On a high-level, simulations with Omniverse™ Physics work as follows:

The USD Physics schema of robot and environment assets are parsed and corresponding simulation objects are created in the selected physics backend.
Then, for each discrete-time step of the simulation, Physics advances the simulation objects given their current state and additional inputs such as, for example, control-policy torques.
The updated state is written back to USD by default, where the state can be further processed by the user, a reinforcement-learning policy, or other extensions such as the Omniverse RTX Renderer.
Omniverse™ Physics propagates runtime changes to physics parameters in USD to the physics objects.

Isaac Sim supports multiple physics backends: the default PhysX SDK backend and the experimental Newton backend.

Tools#