High Precision Positioning Using Acceleration and Displacement Sensors in Piezo-driven Stage Systems

摘要

This paper presents a control design approach to compensate for the phase delay and resonant vibration in the piezo-driven stage systems. A target piezo-driven stage is installed in a capacitive sensor to detect the accurate stage displacement, however, the sensing system generally includes a phase delay due to the data conversion process and lowpass filters in the amplifier to remove the sensor noise. In this study, a MEMS acceleration sensor signal is integrated into the displacement signal detected by a capacitive sensor to improve the phase characteristics at a high frequency range, and the composite filters are designed to synthesize two sensor signals. In addition, the acceleration minor-loop is added to robustly suppress the resonant vibration against the frequency variations. The effectiveness of the design approach is verified by conducting experiments using a commercial piezo-driven stage system.