Till now, a pneumatic cylinder has been used an actuator of automatic machine. But, it's using method is almost based on the on-off control of the piston. Hence, the purpose of this reserch is to control the position of the piston in arbitrary point on the stroke by using a pneumatic servo valve. In this paper, we report on the experimental results of the positioniny accurncy, the static stiffness and the region of controllability under no-hunting (no-chatter).
