Robotic Jellyfish: Unlikely but Formidable Monitor of Earth’s Oceans
Robojelly represents the latest scientific attempt to create a robot that can monitor all kinds of sea activity ranging from the movements of submarines to icebergs.
Seemingly an unusual choice for a model, the moon jellyfish was chosen because it moves easily and silently through the water, utilizing minimal energy.
Its utility as a surveillance tool could be invaluable for both the U.S. Navy’s underwater rescue operations and stealth surveillance, as well as for scientists.
Robojelly is an almost living and almost breathing research tool that could uniquely amass data concerning fish migrations and the development of icebergs over periods of time without disturbing marine life.
“The live moon jellyfish, on which Robojelly is modeled, is a stunningly efficient animal. We looked at the way it moves, swims. Our goal was to create a robot to replicate these things,” says Virginia Tech graduate student and Robojelly creator Alex Villanueva.
What makes Robojelly so unusual is the fact that it represents the first successful powering of an underwater robot using external hydrogen as a fuel source. By running on hydrogen and oxygen, the robot is more adaptable to remaining for long periods in the ocean.
Robojelly is able to mimic the motion of a jellyfish via its rubber silicone dome that expands and contracts. This activity is controlled by heat-sensitive, wires coated with platinum and carbon nanotubes, located under the dome. These wires are rigged up to strings that thread their way outward through each of eight sections on the silicone dome. When the wires come in contact with hydrogen and oxygen, the platinum and carbon ignite and release heat, which in turn causes the wires to tug at the strings. This causes the puffing and unpuffing that characterizes Robojelly’s movements through the ocean.
Robojelly’s design still needs some adjustment before it will be ready to submerge. Currently, Robojelly can travel in only one direction because all eight segments are activated at the same time.
The ultimate goal of Robojelly’s creators is to make the bot completely energy-independent, with the ability to suck in hydrogen and oxygen from the water within which it swims.
For now, it must carry its own energy source, but when it is ready, there is no question that Robojelly will hold its own among other bots that swim undetected in the ocean.
Robojelly and its creators have been featured in the journal, Smart Materials and Structures, published by Britain’s Institute of Physics.