Quick Response Valve for 3DOF Active Control of Pneumatic Vibration Isolation Tables

The rapid expansion of the semiconductor industry and the increasing demand for high speed, high precision positioning stages necessitate exceptionally precise active control of pneumatic vibration isolation tables. This study addresses these stringent requirements by employing a novel pneumatic valve to regulate airflow to the air springs of the vibration isolator. The novel valve incorporates an internal sensor for accurate poppet position monitoring which enables inner loop feedback (FB) control of the poppet position. This effectively compensates for airflow induced disturbances acting on the poppet. Consequently, rapid and precise air spring pressure regulation is achieved which results in accurate displacement control of the vibration isolator. The effectiveness of the proposed system is validated through experiments evaluating its ability to isolate vibration caused from a movable stage mounted on the isolator.