Improvement of Output Displacement of Servo Pneumatic System using Fuzzy PI Controller

Abstract

Pneumatic systems are widely used in industrial automation for theiradvantages such as speed of motion, low cost of maintenance, safe operation and high power/ weight ratio, cleanliness, simplicity of operation as compared with other systems such as hydraulic and electro - mechanical technologies. In this work, a fuzzy PI controller is designed for improving the output displacement of the servo pneumatic system, in order to improve the position transient response. The aim of tuning is to reach minimum steady state error in the output displacement and also to compensate the effect of applyingdifferent types of external load forces. The parameters of the controller are tuned using a trial and error method. A comparison between the results of using Fuzzy PI controller and the PID controller showed that the Fuzzy PI controller has improved the maximum error ratio in position up to 45 % by adding a fixed external load force and up to 19 % by adding variable external load force with highcompensation for the effects of any external load force.