A jellyfish-like robot for mimicking jet propulsion

Soft robotic links that construct a soft skeleton mechanism are needed for mimicking motion of muscle tissues. In this paper, we describe a jellyfish like robot, in which the skeleton has to be flaccid on relaxations and firm on the contractions periods. Our jellyfish robot consists of a series of springs that are connected in a unique configuration. This configuration allows the robot to propel itself forward, as well as to control its propulsion direction. A soft tissue that encases all the springs creates the bell shaped body of the jellyfish robot. Three tension springs shaped in a closed ring configuration are connected parallel to each other by lateral springs. The tension (and therefore the length) of each spring in independently controlled using a tension control mechanism. This configuration allows for various propulsion cycles, mimicking the various propulsion modes of real jellyfish.