Coordinated compliance control of dual-arm robot for payload manipulation: Master-slave and shared force control

With the rapid development of robotics, dual-arm robots have been more and more widely used. Compared with the traditional single manipulator, it is very challenging for a dual-arm robot in modelling, planning and control. In this paper, we propose two compliance control methods for dual arm coordination to meet different requirements of fine manipulation tasks, such as payload carrying, assembly and repairing. The first method is called master-slave force control strategy, and the second is shared force control strategy. For the former, the desired trajectory and operational force of master arm are given in advance. Then that of slave arm are calculated from the closed-chain constraint equation. On the contrary, the two arms can be controlled in shared mode, that is to say, the desired trajectory and operational force of the end-effectors of dual arms are decomposed from the closed-chain constraint equation directly. The coordinated kinematic and dynamic equations of dual-arm robot system are established by considering the closed-chain constraint relationship. According to the force balance equation of the objective payload, the common force is decomposed into the desired end-effector force of each manipulator. Finally, the control algorithms are verified by simulation and experiment.