Pneumatic servo systems are widely used in industrial applicationsbut they are expensive, so decreasing their cost contribute in decreasingproducts manufacturing cost. In this research a pneumatic servo system (PSS)was designed and implemented using cheap conventional directional controlvalve (CDCV) instead of expensive servo or proportional valves. The CDCVwas driven using pulse width modulation (PWM) technique, which wasgenerated in the LabVIEW program and send to the CDCV via Arduino unomicrocontroller board. A fuzzy PI controller was designed and implemented toovercome the nonlinearity inherent in air systems, resulting from aircompressibility and dry friction, and the nonlinearity resulting from the use of aCDCV which is a digital valve. It is found that getting acceptable resultsrequire using PWM technique with frequencies greater than 90 Hz. The resultsshowed that increasing the applied pressure leads to a significant decrease inthe rising time but accompanied with a noticeable increase in the rippleamplitude. So, getting accepted results require choosing the applied pressureexperimentally to suit the applied load, since they are affected by the appliedload.

Pneumatic servo system --- Sequencer --- conventional directional control valve