Coordinated Motion Planning and Optimal Force Distribution for Robots with Multiple Cooperating Arms

This paper is concerned with the problems of inter-arm coordination which arise when multiple robot arms attach their end effectors to a single payload in order to perform a manipulation task. The approach taken is to let the arms cooperate with equal rights, and to exploit the redundancy present in the system for the minimization of a quadratic cost criterion. The main elements of the proposed control system are generators for coordinated nominal motions and force/torque interactions with the payload, and an active compliance scheme capable of resolving kinematic conflicts and inconsistencies between motion and force/torque commands. The paper gives a detailed mathematical description of both the motion and the force/torque generators. The proposed active compliance scheme is presented in summary form.