Adaptive tracking control of rigid robot manipulators by using only joint position measurements

In this paper, a new high-gain observer for rigid robot manipulators is proposed. By combining this observer with several adaptive controllers for rigid robot manipulators, we extend the state feedback(joint position and joint velocity) based adaptive controllers to output(joint position only) feedback based ones. We show that the output feedback based adaptive control system consisting of the observer and adaptive controller(Slotine and Li, 1988) is semi-globally asymptotically stable. Moreover, we show that the adaptive control system consisting of the observer and composite adaptive controller(Slotine and Li, 1989) is semi-globally exponentially stable if the regressor vector is P.E.(persistently exciting). The simulation results have shown the effectiveness of the developed observer and adaptive controller.