collada_urdf: reference joints explicitly rather than by instance
collada_urdf: reference joints explicitly rather than by instance

robotology-dependencies/urdfdom,keulYSMB/urdfdom,robotology-dependencies/urdfdom,shadow-robot/urdfdom,robotology-dependencies/urdfdom,keulYSMB/urdfdom,keulYSMB/urdfdom,shadow-robot/urdfdom,robotology-dependencies/urdfdom,shadow-robot/urdfdom,shadow-robot/urdfdom,keulYSMB/urdfdom