Chattering-Free Sliding-Mode Control for Electromechanical Actuator with Backlash Nonlinearity

• Main Authors: Dongqi Ma, Hui Lin, Bingqiang Li
• Format: Article
• Language: English
• Published: Hindawi Limited 2017-01-01
• Series: Journal of Electrical and Computer Engineering
• Online Access: http://dx.doi.org/10.1155/2017/6150750

Considering the backlash nonlinearity and parameter time-varying characteristics in electromechanical actuators, a chattering-free sliding-mode control strategy is proposed in this paper to regulate the rudder angle and suppress unknown external disturbances. Different from most existing backlash compensation methods, a special continuous function is addressed to approximate the backlash nonlinear dead-zone model. Regarding the approximation error, unmodeled dynamics, and unknown external disturbances as a disturbance-like term, a strict feedback nonlinear model is established. Based on this nonlinear model, a chattering-free nonsingular terminal sliding-mode controller is proposed to achieve the rudder angle tracking with a chattering elimination and tracking dynamic performance improvement. A Lyapunov-based proof ensures the asymptotic stability and finite-time convergence of the closed-loop system. Experimental results have verified the effectiveness of the proposed method.