Adaptive compensation of dynamics and friction for a planar parallel manipulator with redundant actuation

In order to improve the actual tracking accuracy of a planar parallel manipulator with redundant actuation, a new adaptive compensation of dynamics and friction is developed. Firstly, the dynamic model is established in the task space for the parallel manipulator, and a linear parametrization expression with respect to the model parameters is formulated. Then, based on the dynamic model, a new adaptive control law which contains dynamics compensation, friction compensation and tracking error elimination items is designed. The parameter adaptation law is derived by the Lyapunov method, and the convergence of the tracking error and the error rate is proved by the Barbalat´s lemma. At last, the proposed controller is implemented in the trajectory tracking experiments of an actual planar parallel manipulator with redundant actuation.