Position control of an electrostatic linear actuator using rolling motion

Abstract A microactuator consisting of a plane wafer with striped electrodes covered with an insulation layer and a thin cylindrical roller was fabricated. The silicon micromachining techniques were utilized to make the micro electrode patterns and the insulation layer on the plane wafer. Rollers were machined and assembled mechanically. The diameter of the roller was 0.4 mm and the width of driving electrodes was 34 μm. The position of the roller was determined by measuring the capacitance coupling between the roller and each electrode. Voltage up to 110 V was applied to the electrodes just beneath the roller and in the driving direction. The roller was kept at the ground potential and rotated towards the direction where the electric field attracted it. The driving performance, like stepping motors, was examined. The actuator was applied to an electric micro relay.