Robojelly 2.0: Robotic jellyfish now powered by hydrogen The robotic jellyfish gets its power from hydrogen gas, which is pumped in through a tube at the top of the bell. Courtesy of IOP Publishing March 21, 2012, 12:40 p.m. The official term for the robotic jelly is "biomimetic jellyfish," but we prefer to think of it as Robojelly -- flexible robotic king of the high seas. Robojelly is about the size of the palm of your hand and has the ability to change its size and shape as a result of external stimuli, just like its animal counterpart. Engineers used a shape memory alloy (SMA) and silicon to create the robojelly's body, which one researcher described as feeling a bit like an artificial breast implant. The robojelly concept has been floating around since 2009, thanks to a grant from the U.S. Navy, but in a paper published this week in the journal Smart Materials and Structure, scientists say they have made a robotic jellyfish that uses hydrogen to power the opening and closing of the robojelly's bell -- the action allows the jellyfish to move through water. Previous iterations of robojellies needed electricity to function. Someday, robojelly may be able to collect hydrogen from its watery environment to use as a source of fuel, but for now, study lead author Yonas Tadesse said he can imagine robojellies heading out to sea with a little tank of hydrogen attached to their bodies -- like a little scuba tank. And in case you are wondering, Robojellies do have a practical application. They are relatively cheap to produce and can be outfitted with sensors that can detect pollution levels in different parts of the ocean and send that information back to a receiving station. Is Facebook profiling of job applicants fair or legal? Robo-cheetah sets record as fastest animal on four legs