Scientists have built robot jellyfish that could one day be used to track and monitor fragile marine ecosystems. The soft robots can swim through openings narrower than their bodies and are powered by hydraulic silicon tentacles. Several of the bots have already been tested squeezing through holes cut into a plexiglass plate. In future, these so-called'jellybots' could be sent into delicate environments, such as coral reefs, without risking collision and damage. Creators of the artificial animal believe they could act as'guardians of the oceans' without interfering with the delicate wildlife.
Jellyfish float through the ocean like drones of the sea. Their simple nature makes them a natural muse for robot engineers building devices that can squeeze through tight spaces, check the ocean's health, and eventually, explore the human body. This week, a team at Florida Atlantic University unveiled a new eight-inch wide robo-jellyfish built to monitor marine life and harsh underwater habitats. Researchers at Virginia Tech, for example, built a massive 170-pound mechanical one that swims with a parachute-like apparatus.
A fleet of robotic jellyfish has been designed to monitor delicate ecosystems, including coral reefs. The underwater drones were invented by engineers at Florida Atlantic University and are driven by rings of hydraulic tentacles. The robots can squeeze through tight holes without causing damage. One expert praised the design but warned that the man-made jellyfish might be eaten by turtles. The flexible, 20cm-wide bots are modelled on the appearance of the moon jellyfish during its larval stage.
Even though they lack fins and their bodies are gelatinous, jellyfish are some of the most energy-efficient swimmers. They achieve this by making use of their bells to create a wall of water to push off so they can propel themselves more quickly. When flying or swimming, an animal can get a boost from the ground effect, in which drag is reduced and lift increased as they approach a surface. The effect also comes into play in aeroplanes. But moon jellies (Aurelia aurita) spend most of their time in open water, so they don't have surfaces to push against.
Robot squid that move to a rhythm can match the power efficiency of the real animals, a trick that could be useful for designing next-generation submarines. Real squid have small fins that they use for careful manoeuvring, but when a big burst of speed is required they suck in and expel water to propel themselves. Researchers have tried to build robots that mimic this jet-like behaviour, but now a team led by Gabriel Weymouth at the University of Southampton, UK, has discovered a way to boost their efficiency. Weymouth and his colleagues created an umbrella-like robot with eight 3D-printed plastic ribs covered by a rubber skirt. It flexes outwards to suck in water and contracts to expel it, providing thrust.