Dynamic surface control of the single-rod pneumatic actuator with disturbance rejection

In this paper, An adaptive dynamic surface controller (ADSC) is developed for the pneumatic servo systems with the single-rod pneumatic actuator. The ADSC scheme contains a nonlinear feedback part, a parametric adaption part, and a disturbance observer part in the parallel structure. The nonlinear feedback part is synthesized by the backstepping method, while the explosion of complexity in traditional backstepping design is avoided by utilizing dynamic surface control technique. Since precision motion control of pneumatic servo system is always disturbed by unknown model parameters and disturbance, the gradient adaption laws are employed to further estimate and compensate those factors. Experimental results obtained verify the effectiveness of the proposed ADSC controller and its performance robustness to parameter variations and external disturbance in practical implementation.