Cooperative control between two position-controlled manipulators

This paper proposes a simple method for handling a single object by cooperation of two manipulators controlled by PID position controllers. Flexibility is essential to avoid excessive inner forces caused by the mutual positioning error between two manipulators. First, the way to design these flexible mechanisms is shown. Second, the closed loop structure consisting of two manipulators and the installed flexible mechanisms is kinematically analyzed. As an example, a cooperative system between a 6-DOF robot and a conventional crane is designed and an inverse kinematics algorithm is proposed. The method proposed here is also very effective for cooperation in distributed autonomous robotic systems