PRECISE POSITION CONTROL OF A PNEUMATIC SERVO TABLE SYSTEM CONSIDERATION DYNAMIC CHARACTERISTICS OF PNEUMATIC SERVO VALVES

摘要

Using a novel pneumatic actuator and novel pneumatic servo valves, a pneumatic precise positioning system is well constructed. The pneumatic actuator has low friction. The pneumatic servo valve has high performance. It is confirmed that the performance of the pneumatic servo system is affected by the dynamic characteristic of the servo valve. The natural frequency of the servo valve is set three times higher than the best commercial one. We conducted several experiments and made clear that the steady state error of the system becomes lower than ±0.1 μm for step response. Moreover the tracking error of less than ±0.5 μm was realized during sinusoidal motion.