Proportional–derivative impedance control of robot manipulators for interaction tasks

Abstract: This paper addresses the problem of impedance control of robot manipulators. An impedance controller with dynamic compensation, applied to the interaction control of robot manipulators, is presented. Previous results on motion control in task-space are extended to generate the proposed impedance controller. The approach was designed in such a way that it solves two challenges: the regulation of the interaction and a suitable path tracking. The asymptotic stability of the closed-loop system, composed by full non-linear robot dynamics and the impedance controller, is demonstrated in agreement with Lyapunov’s direct method. In addition to the theoretical background, the performance of the proposed controller is verified through simulation and experimental results obtained from the implementation of an interaction task involving a two degree-of-freedom, direct-drive robot