Research on pneumatic torque servo control system based on positional interference2023.4.27 Data

This paper presents an active disturbance rejection torque control strategy integrated with a Kalman filter for a pneumatic rotary actuator without pressure feedback. The interference from the position system and nonlinearity from friction and air compressibility can lead to chatter and crawl, presenting challenges to achieving precise torque control of pneumatic rotary actuators. A Kalman filter is designed for real-time filtering to address the chattering of active disturbance rejection controller (ADRC) caused by noise of feedback signal. The overshoot is reduced by using a tracking differentiator (TD). The total nonlinearity is estimated by designing an extended state observer (ESO). A nonlinear error state feedback controller (NLSEF) is implemented to ensure fast response and control accuracy of the system. Moreover, the effectiveness of the ESO and the convergence of the NLSEF are proven by the Lyapunov stability theory. Experimental results indicate that control accuracy is improved by using the proposed strategy.