Trajectory tracking of 3-DOF spatial robot manipulator

Abstract

3-DOF spatial manipulator is a nonlinear system with strong coupling and external disturbance. In order to realize the high-precision trajectory tracking of manipulator, a novel sliding mode controller is developed by designing a new sliding mode surface with PID. The controller possesses following two appealing traits. First, the chattering problem can be attenuated significantly by introducing the function of sal. Second, mode-free is a feature of the proposed control law. Moreover, the globally asymptotically stability of the closed-loop manipulator system is proved by the theoretical analysis. Finally, the proposed control algorithm not only realizes the high-precision trajectory tracking as shown in the simulation, but also improves the system robustness in comparison to the PID control and sliding mode control (SMC).