The robot controlled by Action Graph cannot move and keeps reporting errors

Omniverse Isaac Sim
1

I made a robot car, and I want to use Action Graph to control its movement, but when I run it, I keep getting an error, and I can’t find the reason,This problem has bothered me for a long time， I hope you can help me answer my doubts, thank you very much!

2023-08-24 03:32:59  [Info] [omni.isaac.core.articulations.articulation_view] initializing view for articulation
2023-08-24 03:32:59  [Warning] [omni.physx.tensors.plugin] Failed to find articulation at '/World/car'
2023-08-24 03:32:59  [Error] [omni.physx.tensors.plugin] Pattern '/World/car' did not match any articulations
2023-08-24 03:32:59  [Error] [omni.physx.tensors.plugin] 
2023-08-24 03:32:59  [Info] [omni.isaac.core.articulations.articulation] initializing handles for /World/car
2023-08-24 03:32:59  [Warning] [omni.isaac.dynamic_control.plugin] Failed to find articulation at '/World/car'
2023-08-24 03:32:59  [Error] [omni.isaac.dynamic_control.plugin] DcGetArticulationRootBody: Invalid or expired articulation handle
2023-08-24 03:32:59  [Info] [omni.isaac.core.articulations.articulation_view] initializing view for articulation
2023-08-24 03:32:59  [Warning] [omni.physx.tensors.plugin] Failed to find articulation at '/World/car'
2023-08-24 03:32:59  [Error] [omni.physx.tensors.plugin] Pattern '/World/car' did not match any articulations
2023-08-24 03:32:59  [Error] [omni.physx.tensors.plugin]

Collected_Move.rar (6.6 MB)

3

Hi @fsb0147 - While the dev gets the chance to look at this issue, you can try to check following things:

  1. Check the path: Make sure that the path ‘/World/car’ is correct. This should be the path to the root of your robot in the USD stage. You can verify this in the Stage window in Isaac Sim.
  2. Check the articulation: Make sure that your robot car is indeed set up as an articulation. If it’s not, you’ll need to set it up correctly. This usually involves defining the bodies and joints of your robot in a URDF file and importing it into Isaac Sim.
  3. Check the initialization: The error messages suggest that the system is trying to initialize an articulation at ‘/World/car’ but is unable to find it. Make sure that your robot is properly loaded and initialized before you try to control it with the Action Graph.
  4. Check the extensions: Make sure that the necessary extensions for working with articulations are enabled. This usually includes ‘omni.isaac.dynamic_control’ and ‘omni.physx’.
4

@rthaker Thank you very much for your help, I have checked your comments, but it is still not working, I am confused, can you help me to check the USD file I uploaded?