Researchers at Florida Atlantic University and the US Office of Naval Research developed soft robotic jellyfish to monitor the reefs, 3D printed from rubber.

The team used the shape of the moon jellyfish (Aurelia aurita) during the larvae stage of its life cycle as inspiration for the design. They 3D printed five jellyfish robots using silicon rubber for the actuators Each jellyfish is made from rubber with a different hardness to test which effect it had on the propulsion efficiency. The jellyfish use hydraulic networks to propel themselves forward.

The robotic jellyfish are designed to swim freely, steer around and swim through narrow openings in order to monitor the ocean’s most fragile parts. The soft hydraulic network actuators prevent any inadvertent damage. The design also removed the need for valves, reducing control complexity, space requirements and cost.

Live jellyfish have neutral buoyancy. To mimic this, the researcher used water to inflate the actuators while swimming.

The researchers also tested the robots’ ability to swim through narrow openings, simulated using circular holes in a plexiglass plate. The robots were able to swim through openings narrower than the nominal diameter of the jellyfish.

In the future, the engineers plan to incorporate environmental sensors like sonars, to enable it to find gaps and determine if it can swim through them.

Photo: Simon Davies (via Techxplore)