Distributed Motion Control of Multiple Mobile Manipulators for Reducing Interaction Wrench in Object Manipulation

In real-world cooperative manipulation of objects, multiple mobile manipulator systems may suffer from disturbances and asynchrony, leading to excessive interaction wrenches and potentially causing object damage or emergency stops. This paper presents a novel distributed motion control approach aimed at reducing these unnecessary interaction wrenches. The control strategy for each robot only utilizes information from the local force sensors and neighboring robots, without the need for global position and velocity information. Disturbances are corrected through compensatory movements of the manipulators. Besides, the robustness of the control law against communication delays between robots is also considered. The stability of the control law is rigorously proven by the Lyapunov theorem. Subsequently, the efficacy of the proposed control law is validated through simulations and experiments of collaborative object manipulation by two robots. Experimental results demonstrate the effectiveness of the proposed control law in reducing interaction wrenches during object manipulation.