Adaptive fuzzy Sliding Mode Trajectory Tracking Control of a 7-DOF Redundant Hydraulic Manipulator

Abstract For trajectory tracking control problem of a 7-DOF redundant hydraulic manipulator, an adaptive fuzzy sliding mode control method based on a novel fast reaching law is proposed. Based on the kinematic analysis of the manipulator, the dynamic equation of the manipulator is constructed by using the Lagrange dynamic equation. A trajectory planning method for the manipulator integrating seventh-order polynomial interpolation and genetic algorithm optimization is proposed. Taking the planned trajectory as the expected trajectory, the sliding mode controller is designed to achieve trajectory tracking control of the manipulator. A sliding mode disturbance observer is used to observe the system modeling error, and an adaptive fuzzy logic system is designed to estimate the observation error of the disturbance observer. The sliding mode control law is deduced based on the fast reaching law, which can achieve global fast convergence of the sliding mode function while reducing the chattering of the controller. The simulation results show that the proposed control method has good tracking performance and strong robustness.