How can i fix DcGetArticulationRootBody: Invalid or expired articulation handle

[benson.ee12]

i follow https://docs.omniverse.nvidia.com/isaacsim/latest/tutorial_ros_manipulation.html to control my TM5 robot arm but meet this error . how can i fix it

[benson.ee12]

here are another problem that

[Error] [omni.graph.core.plugin] /arm/ros1_publish_joint_state: Prim is not an articulation

but i already set the articulation root.

[rthaker]

Hi @benson.ee12 - The error messages “DcGetArticulationRootBody: Invalid or expired articulation handle” and “[Error] [omni.graph.core.plugin] /arm/ros1_publish_joint_state: Prim is not an articulation” suggest that there might be an issue with the articulation handle in your physics simulation or the prim you’re trying to use is not an articulation.

Here are some steps you can take to troubleshoot these issues:

1. Check Initialization: Ensure that the articulation has been properly initialized before you try to use the handle.

2. Handle Usage: Make sure you’re not trying to use the handle after the articulation has been deleted or removed from the simulation.

3. Articulation Definition: Verify that the articulation is properly defined in your code. This includes checking that all necessary parameters and attributes are correctly set.

4. Prim Type: The error message suggests that the prim you’re trying to use is not an articulation. Make sure that the prim you’re trying to use is indeed an articulation. You can do this by checking the type of the prim before trying to use it.

5. Update or Reset: If you’ve made changes to the articulation during the simulation, you might need to update or reset the articulation handle.