Dynamic identification of a redundantly actuated parallel manipulator

The dynamic and friction parameters of a redundantly actuated parallel manipulator are identified by using the weighted least square (WLS) method. The dynamic model with nonlinear friction is formulated in the joint space for the parallel manipulator, and it is expressed in its linear matrix form with respect to the dynamic and friction parameters. In the WLS method, the difference algorithm of joint angles, filter of actuated torques, and the well-excited trajectory of the end-effector are designed to get satisfying estimated results. Another type of the end-effector trajectory is adopted to verify the estimated parameters. In order to compare the identified model with the nominal model, the torques of the active joints is calculated by the estimated parameters and the nominal parameters, respectively.