Abstract
The difficulty of the precise positioning by the pneumatic servo system has not been clearly explicated. This paper analyzes the dynamic behavior of the pneumatic cylinder on the position control system and examines factors that make a precise positioning difficult. It is certain that the main factor is the complex relation between the friction force and the compressibility of the air, which causes the time lag in the driving force. From these results, the effective steps to realize the precise positioning with the pneumatic cylinder are described. Practically, it is possible to compensate the influence of this time lag and improve the position control features by means of the use of the pressure cascade control loop. It is also proposed that the pressure cascade control can be replaced with the acceleration feedback control which has the more simple composition.
