Development of Underwater Microrobot with Biomimetic Locomotion

Abstract

Microrobots have powerful applications in biomedical and naval fields. They should have a compact structure, be easy to manufacture, have efficient locomotion, be driven by low voltage and have a simple control system. To meet these purposes, inspired by the leg of stick insects, we designed a novel type of microrobot with biomimetic locomotion with 1‐DOF (degree of freedom) legs. The locomotion includes two ionic conducting polymer film (ICPF) actuators to realize the 2‐DOF motion. We developed several microrobots with this locomotion. Firstly, we review a microrobot, named Walker‐1, with 1‐DOF motion. And then a new microrobot, named Walker‐2, utilizing six ICPF actuators, with 3‐DOF motion is introduced. It is 47 mm in diameter and 8 mm in height (in static state). It has 0.61 g of dried weight. We compared the two microrobot prototypes, and the result shows that Walker‐2 has some advantages, such as more flexible moving motion, good balance, less water resistance, more load‐carrying ability and so on. We also compared it with some insect‐inspired microrobots and some microrobots with 1‐DOF legs, and the result shows that a microrobot with this novel type of locomotion has some advantages. Its structure has fewer actuators and joints, a simpler control system and is compact. The ICPF actuator decides that it can be driven by low voltage (less than 5 V) and move in water. A microrobot with this locomotion has powerful applications in biomedical and naval fields.