By Andy Choi
Researchers from America have designed a robotic jellyfish called Robojelly.
With various integrated features and powered by hydrogen, it is suitable for rescue operations and underwater search.
Robojelly is designed using smart materials that are capable of generating conformational changes when stimulated. When placed in a water tank, powered by chemical reactions on its surface, Robojelly will imitate the natural movements of a jellyfish.
The results provided by Virgina Tech researchers for constructing Robojelly have been published in IOP Publishing's journal Smart Materials and Structures dated 21 March.
The jellyfish, being an invertebrate shows two prominent swimming mechanisms such as ‘rowing’ and ‘jetting’. The mechanism involving the contraction and the subsequent progressive movement of the jellyfish with the help of its bell has been adopted while constructing the vehicle. Commercially-available shape memory alloys (SMA) serve as smart material-components for construction. These materials are protectively enclosed in carbon nanotubes, with a platinum black powder coating and remember their original shape.
The robot is fuelled by chemical reactions between the platinum on its surface and the oxygen and hydrogen in water that can generate heat. The heat resulting from the reactions is transmitted on to the robot’s artificial muscles, thereby stimulating transformational changes in it. Without any external power source, Robojelly is capable of regenerating fuel from its natural surroundings.
At present, installed in a water tank, the hydrogen-powered Robojelly is functional. According to the researchers, the robot has to undergo further developments to attain maximum efficiency and full functionality.
Supported by the Office of Naval Research, this study is part of the MURI initiative.