Abstract
We propose a control algorithm for air cylinder actuator which has a normal PID controller with a variable offset pressure controller, so as to achieve the high speed response and less overshoot. The offset pressure is used as constant in the conventional control algorithm, which gives the stiffness to the air cylinder actuator piston. Our control algorithm therefore adopted a time-variant offset pressure in each air cylinder actuator chamber, so that the actuator properly increase or decrease the stiffness according to the target. The experimental results showed that a rise time was almost the same as that of PID controller, but tracking improved by 40% compared with a normal PID controller when the lamp of target was more moderate.
