Dual Excitation Electrostatic Stepping Motor.

Abstract

Electrostatic motors have been believed to be weaker than electromagnetic motors which are typically used for mechatronic devices. However, electrostatic motors are preferable to electromagnetic ones for micro mechanical applications since their force per volume ratios increase as their dimensions are reduced. This follows that a large output should be obtained if a large number of such small sized motors with high force per volume ratios are linked and their outputs are aggregated. This paper proposes an electrostatic drive technology which is applicable to such a large output motor. The element motor, which is named Dual Excitation Electrostatic Stepping Motor, consists of a pair of plastic films, slider and stator. Both of the films have parallelly located electrodes embedded in them, and the slider moves along the surface of the stator when defined rectangular pulse voltages are applied to the electrodes both in the slider and the stator. Force generation characteristic of the electrostatic motor is calculated by surface charge method. A prototype fabricated using flexible print board technology weighs 7g and generates a thrust force of 1.9N at an excitation of ±1000V.