A cooperative task-space control law for two-manipualtor systems

摘要

In this paper a system of two cooperative manipulators tightly grasping a rigid object is considered. First, the cooperative task space is defined as a set of meaningful absolute and relative variables fully characterizing the system. Based on this formulation, a task-space control stragegy is devised, where orientation errors are computed through quaternions. Further, kinetostatic filtering of the control action is introduced to cancel out internal stresses on the held object at steady state. In order to achieve internal force regulation, force feedback is added to the proposed control law. The analysis of the equilibrium is developed and its stability properties are studied by resorting to Lyapunov second method.