Adaptive Finite-time Control for Electromechanical Servo System with Mismatched Uncertainties

Abstract

The electromechanical actuator (EMA) consists of electrical and mechanical parts, and the frictions, backlash, and multi-parameter coupling characteristics will seriously affect its position-tracking performance. To improve the control accuracy and anti-disturbance ability of EMA, a robust control system is proposed in this paper. First, the system structure of the EMA is analyzed, and the adverse effects caused by backlash and other parameter mismatches are treated as system disturbances respectively. Second, a finite-time state observer is designed to estimate the disturbances in real time. Aiming at the mismatch characteristics of system disturbances, a composite control law is proposed to compensate for the system uncertainties and regulate the output position of EMA. Finally, numerical simulations are conducted to verify the effectiveness of the proposed method.