A couple of years ago, a team of scientists from the University of Leeds succeeded in getting live stickleback fish to follow a computer-controlled "Robofish" as it was moved through their aquarium. Part of the reason for the experiment was to learn about fish behavior, in hopes that human interference in their migration routes could be minimized. While the Robofish was simply a plaster model, researchers from the Polytechnic Institute of New York University recently conducted a similar experiment, but using an actual tail-flapping robotic fish. Their discoveries could help save wild fish populations in the event of environmental disasters.

The study was conducted by NYU-Poly's Maurizio Porfiri and Stefano Marras. Their biomimetic fish, as it was called, was placed in a tunnel of flowing water, along with a school of golden shiners. At first, the scientists kept its tail absolutely still, and the shiners showed little interest. As its tail began to move, however, the shiners started to fall in behind it.

Through varying the speed of its tail beats, the researchers noted that the tail beats of the following fish were always accordingly somewhat slower, which suggested that they were saving energy by riding in the slipstream of the robot. This falls in line with what has been observed in nature, where leading fish exhibit faster tail beats than the rest of the school.

It is hoped that in the future, descendants of the biomimetic fish could be used in natural settings, to lead groups of wild fish away from polluted areas or structures such as dams. Likewise, devices such as robotic birds could perhaps be used to lead other types of animals to safety.

"These experiments may open up new channels for us to explore the possibilities for robotic interactions with live animals - an area that is largely untapped," said Porfiri. "By looking to nature to guide our design, and creating robots that tap into animals' natural cues, we may be able to influence collective animal behavior to aid environmental conservation and disaster recovery efforts."

A paper on the research was recently published in the Journal of the Royal Society Interface.

Source: Polytechnic Institute of New York University