Practical Prescribed-Time Trajectory Tracking Control for a Novel Tendon-Driven Space Manipulator via Fully Actuated System Approaches

This article investigates the prescribed-time control for a novel tendon-driven space manipulator with uncertainties and deformations in the extensive operations. Considering the elastic potential energy loss moment of the rope and the coupling of the joint motion under the coordinated drive of multiple motors, the dynamics model of the space manipulator is established by the Lagrangian method. The dynamical model is transformed into a class of second-order fully actuated nonlinear systems using an equivalent transformation. Then, a practical prescribed-time controller is designed using the high-order fully actuated system approach. The designed control method is characterized by two features: first, high tracking accuracy is achieved by transforming the nonlinear system control problem into a linear system control problem through fully actuated system approaches; second, fast trajectory tracking is obtained by using the prescribed-time control technique. Finally, numerical simulations and physical experiments are performed to demonstrate the effectiveness and superiority of the proposed control method.