Parameter tuning process for a closed-loop pneumatic actuator

Pneumatic drives are light weight, small-sizes, simple to install and to maintain. Pneumatic drives have a robust design and operation. They are clean and cheap, have no temperature limitation, and so, they are preferred in many branches of manufacturing and process industry. The well-known pneumatic actuators are widely used in closed-loop positioning systems because of their dynamic performance and mechanical flexibility in different electro-mechanical systems arrangements. The goal of the paper is to find the parameters of a closed-loop pneumatic actuator so that a good dynamic behaviour of the system is obtained. The parametric tuning process is developed by using numerical simulation technique. So, it was seen that using a proportional controller, the pneumatic actuator has an asymptotic stability for different values of the proportional gain K_p. Starting with K_p = 8 the system remains stable, but oscillations of low amplitude appears.