Dynamics of Internal Motion of Redundant Manipulators

In the paper the dynamic properties of the internal motion of redundant manipulators are considered. The motion is decoupled into the end-effector motion and the internal motion. Next, the dynamic model of a redundant manipulator is derived. A special attention is given to the inertial properties of the system in the space where internal motion is taking place; we define a null space effective inertia and its inverse. Finally, a control method is proposed which completely decouples the motion of the manipulator into the task space motion and the internal motion, and enables the selection of dynamic characteristics in both subspaces separately.