I’m encountering an issue where the active joints at the end of a parallel leg structure cannot be loaded into the articulation in IsaacSim. As shown in the video, (https://www.youtube.com/watch?v=FYDQgmslNUU) the upper part of the five-link parallel leg structure is driven by two joints named *Drive, while the lower part, which includes the wheels, has joints named *Wheel. All other joints are set as passive and have been excluded from articulation.
Currently, only the *Drive joints are correctly loaded, while the *Wheel joints are showing as unmatched to their targets. I have tested both the robotenv_cfg method in IsaacLab and the Omnigraph method in IsaacSim, but neither seems to recognize the *Wheel joints.
Has anyone experienced a similar issue? This would be particularly useful for walking robots with ankle joints and wheel-legged robots.
In IsaacLab,
ValueError: Not all regular expressions are matched! Please check that the regular expressions are correct:
LeftMotorDrive: [‘LeftMotorDrive’]
LeftPassiveDrive: [‘LeftPassiveDrive’]
RightMotorDrive: [‘RightMotorDrive’]
RightPassiveDrive: [‘RightPassiveDrive’]
LeftWheel:
RightWheel:
Available strings: [‘LeftPassiveDrive’, ‘LeftMotorDrive’, ‘RightMotorDrive’, ‘RightPassiveDrive’]
If you are trying to control a drive at the end of legs like those on the diablo robot, I believe you would want to include all of the joints in the articulation but only put drives on those joints you would like to explicitly control.
Hi, Strain, thank you for your reply. I think your suggestion will be working on some serial structure robot, but not on my case. If I add all parallel joints into the articulation tree, the model will be crashed into pieces immediately.