MODELING AND ANALYSIS OF ELECTRO-THERMAL MICROACTUATORS

This paper presents a dynamic model for analyzing the static and dynamic performance of electro-thermal microactuators. In the proposed model, we adopt a lumped approach that decomposes the electro-thermal-mechanical system into a series of electrical resistors, heat resistors, heat capacitors, and a mechanical frame. In this study, we first verified the proposed model through experiments, and then investigated the effects of the design parameters on system performance. The system performance measures included static gain and corner frequency. The design parameters included the actuator size, the width ratio, and the length ratio. The results reveal that: ( 1) The static gain is proportional to the actuator size; ( 2) The corner frequency is inversely proportional to the actuator size; ( 3) The effect of the width ratio on the static gain is not significant; ( 4) There exists a compromise value of length ratio so as to achieve a maximum static gain; ( 5) The effects of the width ratio and the length ratio on corner frequency are negligible.