Robust Control on High-Speed Positioning of Pneumatic Servo System

Abstract

The purpose of this study is to propose a robust control strategy on high-speed positioning of pneumatic servo system, for the changes of system parameters and load mass, and frictional force. Bang-Bang control scheme based on the switching time is one of the most efficient control strategy for high-speed positioning, however this control scheme is influenced by the changes of system parameters and load mass because of the open-loop control. In order to overcome these defects, a concept of disturbance observer is introduced into Bang-Bang control scheme. That is, the changes of system parameters and load mass can be estimated by a disturbance observer, and the switching time in Bang-Bang control can be modified so as to correspond to the changes of system parameters and load mass, under controlling. It is investigated that the proposed control strategy is effective for the robust high-speed positioning of pneumatic servo system with a pneumatic rodless cylinder, through some experiments.