離散時間系を考慮した静圧軸受エアステージの軌道制御

抄録

Previously, we developed the air servo stage available ultra-precise positioning where seals are removed from the pneumatic actuator to reduce the effects of friction force, and the slider of the actuator is mounted with air bearings. The air servo stage available is required not only positioning accuracy but tracking performance for trajectory. However tracking performance in accelerating is not sufficient and considerable tracking error occurs. One of the reasons is calculation delay of the controller using a micro-computer. In this paper, we design the servo valve controller as a discrete time system and apply the calculation delay compensator (CDC). As a result, the dynamic frequency of the servo valve increases twice and tracking error decreases because the loop gain of position controller can be higher.