Laser Scanning Drive of the Peristaltic Micro-Gelrobot with Soft Rigid Hybrid Structures

We present a micro-gel robot driven by irradiation of a laser. The proposed micro-gel robot mimics living organisms and moves by peristaltic motion. In this paper, we show the micro-gel robot has multiple soft structures and rigid structures. The soft structures work as actuators like muscles and rigid strictures work as supporting bodies like skeletons. As rigid structures, SU-8 which is hard photoresist is used. As soft actuators, bioresist which is a photo-patternable temperature responsive gel is used. Bioresist swells by absorbing water at lower temperature than 32°C and shrinks bυ releasing water at higher temperature than 32°C. Thus, we use this changing volume as a displacement of an actuator. In addition, we mixed bioroesist with graphene as light absorber to actuate this gel actuator by near infrared laser irradiation. The proposed micro-gel robot is fabricated by using photolithography which is a common MEMS fabrication process. Additionally, fabrication process of the proposed micro-gel robot include release process of the robot from the glass substrate. For release of micro-gelrobot, we use sacrificial layer made of dextran which is a kind of polysaccharide. We use digital mirror device (DMD) to irradiate patterned light to actuate multiple gel actuators. We succeeded in driving the proposed micro-gel robott using laser scanning. In addition, we evaluate a displacement of the peristaltic motion. The proposed micro-gel robot can move for" and by performing a peristaltic motion.