Think of USD as a scene description
OpenUSD describes scene content and how that content is assembled. In a robotics workflow, that can include an environment, objects, visual materials and authored physical properties. A renderer or simulator interprets the relevant data; USD is not itself a physics engine.
The OpenUSD introduction explains this distinction and the composition system. For engineering work, the useful starting point is a scene that can be inspected, reused and changed without losing where its data came from.
Four concepts to recognize
| Concept | Practical use |
|---|---|
| Stage | The composed scene an application opens and inspects |
| Prim | An addressable scene element, identified by a path |
| Layer | A file containing authored scene opinions |
| Reference | A way to reuse content from another asset in a scene |
These concepts are defined in the OpenUSD glossary. Learn the difference between an individual file and the composed stage: a scene may depend on multiple layers and referenced assets.
Keep reusable content separate from task setup
A useful project layout separates an asset's source package from the scene used for a particular test. Put task-specific placement and overrides in your own scene instead of destructively editing the supplied package. This makes it easier to reproduce an earlier result and update the source asset later.
Before making an override, identify the correct prim path and layer. Review the resolved value after the edit, especially when several layers contribute to the same object. File names alone will not explain which setting wins.
Inspect physical content explicitly
The UsdPhysics schema provides data models for rigid bodies, collision, joints and related properties. Your simulator's support and interpretation still matter. Document any engine-specific extensions and test the intended interaction in the chosen runtime.
A practical exchange checklist
Send a colleague the package and entry-file instructions, then ask them to open it from a different directory. Check missing dependencies, scale, materials and the expected prim paths. Run one representative interaction and save the settings needed to repeat it.
Use our packaging tool to bundle supplied USD dependencies and review its findings. Continue with the scene composition guide when combining assets into an environment.