A Robust Controller for Positioning Control of Pneumatic Servo System: Design and Experiment Tests

摘要

The pneumatic cylinders are difficult to be controlled due to flow characteristics of control valves, compressibility of air, and static and dynamic friction forces. This paper describes the development of a robust controller based on H_∞ control theory for positioning control of a high-speed pneumatic cylinder. To design the H_∞ controller, one has selected appropriate weighting functions of pneumatic servo system. Simulation results show that the system is robust during the whole response process and can suppress the disturbance. Finally experiments have been performed with varying supply pressures and load mass. Experimental results imply that good performance and robustness of positioning in pneumatic servo system can be obtained using H_∞ controller.