I’m using Drake’s Toppra implementation to post-process a path produced by GcsTrajectoryOptimization. Things work fine until I put in acceleration limits.

I have been using the PidController for my 7dof robot in Drake, and now I want to try out the JointStiffnessController. However, the JointStiffnessController takes in a MultibodyPlant, and it throws an exception if the dimensionality of the plant is different than the dimensionality of the controlled variable. However, my plant has other models besides my robot (e.g. it has a gripper as well, and some cereal boxes). So I have a conceptual question and then a practical question.

I’m trying to upload my hexapod urdf onto drake. I followed the online instructions and finally got model run successfully on drake. However, its behavior is weird. Its legs are all pointing up, as shown below, which doesn’t make sense. When I have the model freely floating and with gravity, all the legs should be on the ground. The gravity works fine when all my legs are not on the ground, the hexapod drops. Can you please enlighten me what happens with my model?