Augmented acceleration feedback control of parallel manipulators

The acceleration feedback is applied to the motion control of parallel manipulators to restrain the trajectory disturbances, and thus improve the trajectory tracking accuracy. The acceleration signals are estimated based on the constraint equation of the parallel manipulator, and the dynamic model is established in the active joint space. The acceleration feedback is combined with the dynamic model compensation, and a new augmented acceleration feedback (AAF) controller is proposed. The closed-loop system controlled by the AAF controller is proven to be Lyapunov stable, and the exponential stability can be proved further by analyzing the cross term in the Lyapunov function. The trajectory tracking experiments of the planar parallel manipulator by using the AAF controller are carried out and the experimental results are compared with the traditional APD controller.