Engineers Create A Prosthetic Device That Helps Jellyfish Swim Faster

Engineers from Stanford and Caltech have announced that they have created a tiny prosthetic device that can be attached to jellyfish to make them swim faster and more efficiently than normal. They say that the prosthetic device doesn't stress the jellyfish either. The team thinks that in the future, jellyfish equipped with sensors could be directed to explore and record information about the ocean.

Jellyfish use a pulsing motion to propel themselves forward and swish their tentacles around to capture prey. The new prosthetic device the team created uses electrical impulses to regulate and speed up that pulsing. They say that the device is similar to how a cardiac pacemaker regulates the heart. In water, the prosthetic is neutrally buoyant and is about two centimeters in diameter.

It's attached to the jellyfish with a small wood barb. Typically, a jellyfish swims at a rate of two centimeters per second. While they can swim faster, doing so doesn't aid them in ensnaring prey. In testing, the team fitted a jellyfish with a microelectronic controller pulsing at three times faster than the usual body pulses. The result was an increase in speed of around 4-6 cm per second.

The electrical jolts also made the swimming more efficient. While the jellyfish were more efficient and swam three times faster than usual, they used twice as much energy to do so. The jellyfish are said to be 1000 times more efficient than swimming robots. Engineers on the project say that the jellyfish were closely monitored to make sure they weren't harmed.

While the jellyfish has no brain or pain receptors, they secrete mucus when stressed, and no secretion was observed in the experiment. When the prosthetic was removed, they went back to swimming normally.