Closed ozhanozen closed 2 months ago
Thank you for bringing this up.
We are aware of this issue and have reported it to the PhysX team to fix the regex parser on their side. The immediate fix is to ensure the asset follows a flat hierarchy of rigid links.
If you don't care about all the bodies in the articulation, a more temporary solution is to replace the regex expression on the line you highlighted with the bodies you care about. Although ugly, hopefully, it lets you use the class.
Thank you for bringing this up.
We are aware of this issue and have reported it to the PhysX team to fix the regex parser on their side. The immediate fix is to ensure the asset follows a flat hierarchy of rigid links.
If you don't care about all the bodies in the articulation, a more temporary solution is to replace the regex expression on the line you highlighted with the bodies you care about. Although ugly, hopefully, it lets you use the class.
Thanks for the workarounds!
Hi @Mayankm96, I am having the same issue @ozhanozen described. I tried to replace the regex expression with multiple different versions, but none of them worked (ChatGPT couldn`t help me either). For example: "/robot/(body1|body2)" works, but when I use "/robot/(body1|body2|Xform/body3)" I get the error Pattern '/robot/(body1|body2|Xform/body3)' did not match any rigid bodies.
The interpretation of the regex expression seems to be very restrictive, or am I missing something?
Any help would be appreciated.
Describe the bug
When an Articulation is initialized,
_initilize_imp()
function tries to construct the body paths by simply combining the root prim path and body names within the articulation tree:https://github.com/NVIDIA-Omniverse/orbit/blob/477cd6b3f6f37bdf8d7d8a47bf6ea8bb15376c3b/source/extensions/omni.isaac.orbit/omni/isaac/orbit/assets/articulation/articulation.py#L490-L502
However, this leads to incorrect paths for the bodies that are not right under the root prim.
For example, if there is an Xform to group a few bodies together:
the prim path for body3 is assumed to be on /robot/body3 rather than /robot/Xform/body3.
Eventually, the RigidBodyView is not constructed correctly, and this raises a RuntimeError at the following lines due to the mismatch of the
body_names
with thephysx_body_names
:https://github.com/NVIDIA-Omniverse/orbit/blob/477cd6b3f6f37bdf8d7d8a47bf6ea8bb15376c3b/source/extensions/omni.isaac.orbit/omni/isaac/orbit/assets/articulation/articulation.py#L510-L512
Steps to reproduce
Using any Articulation with a similar hierarchy reproduces the error.
System Info
Additional context
200 and #208 are probably related to this.
Checklist