Isaac Sim Freezes on URDF with 690 Joints (Mecanum Wheels Belt)

Hi everyone,

I’m trying to simulate a mecanum wheel belt in Isaac Sim. The URDF includes:

  • 16 continuous joints for drive shafts
  • 672 continuous joints for rollers on the mecanum wheels
  • 2 fixed joints

Total: 690 joints, with 688 active.

The model loads correctly, but once I hit Play, Isaac Sim freezes or becomes unresponsive.
What should I do to make it work?
This is how belt urdf looks like in rviz

kit_20250729_124814.log (2.8 MB)
This is log file

Hi @chaitanyagumudala961, thank you for your question. If you try using CPU Physics instead of GPU physics do you run into this error? You can do that through the simulation settings window: Simulation Management — Omni Physics

Hi @michalin Thank you for reply.
I am running this on GPU. When i load this model the App freezes and stops

Hi @chaitanyagumudala961, thanks for the reply. What I am suggesting is to swap to use CPU Physics just to isolate the issue and check if it is coming from Physics running in GPU.

Hi @chaitanyagumudala961, were you able to try to run the simulation with CPU Physics?

No

The app reported a crash

Any chance you can share the USD setup so I can help debug this on my side?

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