Something’s Fishy about this Robot
When it comes to speed and maneuverability, fish leave man-made submersibles floundering, but RoboTuna and friends may change all that
In a long and narrow basement room at the Massachusetts Institute of Technology, RoboTuna has been taught to swim. RoboTuna is a "biomimetic" (imitating nature) Atlantic bluefin tuna that was conceived in the laboratory of Michael Triantafyllou, a professor of ocean engineering there. Why, he and his collaborators wondered, had no useful technologies ever been developed from studies of how fish swim? There was a definite need to improve upon the design of autonomous underwater vehicles. Could the propulsion system used by fish be applied to submarines or even surface ships? First they had to find out what made fish such efficient swimmers.
David Barrett, then a Ph.D. candidate at MIT, designed and built RoboTuna I using what he called "reverse engineering," finding out how Mother Nature, through thousands of years of genetic changes, taught fish to swim. Once RoboTuna was swimming well, Triantafyllou and his group began to analyze the play of water around the fish. The secret to efficient swimming, they found, was vorticity control. Fish propel themselves by manipulating the eddies they encounter in the water and those they create themselves by swishing their tails.
Several descendants of RoboTuna have been spawned, including RoboPike and a free-swimming robotic tuna developed at Draper Laboratory by Jamie Anderson, called VCUUV (for Vorticity Control Unmanned Undersea Vehicle). It is hoped that one day autonomous vehicles can use the efficient mechanics of fish propulsion for scientific research at sea.