A ModelPlugin can't be attached to a <joint>; it must be attached to the <model>. Perhaps you can add a parameter to your <plugin> that takes the name of the joint to use for the motor?
A ModelPlugin can't be attached to a <joint>; it must be attached to the <model>. Perhaps you can add a parameter to your <plugin> that takes the name of the joint to use for the motor?
A ModelPlugin can't be attached to a <joint>; it must be attached to the <model>. Perhaps you can add a parameter to your <plugin> that takes the name of the joint to use for the motor?