Force control of a multi-arm robot system

Kinematic resolved-rate control is extended to the coordinated control of multiple robot arms cooperatively manipulating a single object. To provide the capability to control the forces applied to the jointly manipulated body and to the external environment, a force feedback loop is closed around the system. This results in a multiarm realization of the damping control method. The problem of redundancy in determining the distribution of loads among the manipulators is handled by minimizing a quadratic cost function in task-space force and torque. A coordinate system structure is described that permits manipulator control relative to a control reference frame which may be independent of the base coordinate systems of the respective manipulators and of the world reference system