A Microactuator Using Phase Transition of Paraffin : Development of an Actuator with Scissors for Surgical Operation

Abstract

Our aim is to develop a microactuator to be used for endoscopic surgery. The purpose of this study was to construct cylinder-piston-type microactuators that are actuated by phase transition of material. We use a paraffin as the working material because paraffin has a large coefficient of expansion due to the phase transition in the temperature range of 35 to 45 degrees of centigrade. Firstly, we made a microactuator whose outer diameter was 1.5 mm and the length was 65 mm. The actuator generates the stroke of 2 mm against the load of 1 kg. Secondly, a micro-scissors was attached to the piston of the actuator. It was confirmed that the micro-scissors can cut the paper, string and rubber tube without any trouble. The operation time for one cycle of cutting was approximately 13 secondns.