Trajectory tracking control of a 3-CRU translational parallel robot based on PD+robust controller

In order to suppress the external disturbances existing in the trajectory tracking process of the 3-CRU parallel robot, a trajectory tracking control method based on PD+robust controller is proposed in this paper. The kinematic model of the 3-CRU parallel robot is established to solve the kinetic energy and potential energy of the system. The basic dynamic model of the 3-CRU parallel robot is obtained based on Lagrangian formulation, and the complete dynamic model of the parallel robot is established by introducing Coulomb and viscous friction. Based on the analysis of the factors affecting the stability of PD controller, a trajectory tracking control method based on PD+robust controller is proposed, and it is proved theoretically that the system converges stably and has a good external disturbance suppression effect. The method has the characteristics of easy implementation and strong applicability of PD controller and strong robustness of robust controller. Experimental results prove the effectiveness of this method.