Robust position tracking control for rigid-link flexible-joint robots

Abstract

The robust tracking controller for rigid-link flexible-joint (RLFJ) robots presented by D. M. Dawson et al. (1991) is redesigned. The controller exploits aspects of the dynamic model to provide a global uniform ultimately bounded (GUUB) stability result despite the presence of parametric uncertainty, joint flexibility, and mechanical actuator dynamics. The controller delivers the GUUB result for both the position and the velocity error. The redesign enables the final ball in which the link tracking error resides to be arbitrarily shrunk and the exponential rate at which the error approaches that ball to be increased by adjustment of the control gains.