Cooperative control of two industrial robots with force control devices

This paper proposes a new strategy for manipulation of a rigid object by cooperation of multiple position-controlled manipulators using force control devices. The force control device consists of springs and a position-controlled micro-manipulator. Force control is achieved by controlling deflections of each spring by the micro-manipulator. A cooperative control algorithm considering the flexibility of macro/micro manipulators is proposed. After the differential equation of the error vector system is derived, a method of designing feedback gain matrices is shown for linearizing the system. To verify the efficiency of the algorithm, experiments are done on carrying an object by two industrial robots.