Driving mechanism of a new jellyfish-like microrobot

In recent years, many kinds of underwater microrobots have been developed. Some of them are multi-DOF and flexible. In this paper, we present a novel type of underwater jellyfish-like microrobot, mimicking the prototype of hydrozoan medusae. Its anatomic configuration is analyzed and a simple driving device is advanced to simulate the jet propulsion of jellyfish. The microrobot is driven by a SMA (shape memory alloy) coil spring and two ICPF (Ionic Conducting Polymer Film) actuators. The main driving mechanism is a wooden quadrangular framework controlled by the SMA actuator and two ICPF actuators help to change the swimming direction. Experiments are given and the morphological parameters and the thrust force of the jellyfish-like microrobot are calculated. The theoretical parameters and actual parameters are also compared for further improvement.