Finite-time anti-disturbance tracking control for flexible manipulator based on backstepping method and disturbance observer

Abstract

This paper proposes a finite-time anti-disturbance control strategy for a single-link flexible manipulator system affected by external disturbances. The strategy combines a disturbance observer with a finite-time control law for estimating unknown disturbances and tracking desired trajectories. The controller is designed using the backstepping method and system stability is analyzed with Lyapunov stability theory. The results show that the strategy maintains system convergence to an equilibrium point under external disturbances. Simulations validate the effectiveness of the control method, with tracking error converging to zero within a finite time and the manipulator tracking the desired trajectory. The disturbance observer accurately estimates the error, highlighting the robustness of the proposed strategy.