Adaptive tracking control for rigid-link manipulators with joint flexibility

In order to simplify the dynamic analysis as well as the subsequent controller design, robots are generally modeled by rigid links with rigid transmission mechanism. However, the effects of joint elasticity may become significant especially when the payload is heavy or the operation speed is high. In such situation, the control performance will be deteriorated if the joint flexibility is not taken into account in the controller design. Therefore, we present an adaptive variable structure Lyapunov-based control scheme to circumvent such problems. It only requires the measurements of position and velocity signals of links and motor shafts. Besides, all the system parameters are assumed to be unknown a priori, and the asymptotic stability of the overall system can be concluded by the Lyapunov theory. In the simulation studies, the effectiveness of the proposed control algorithm is also demonstrated