Robots can already mimic people, dogs, cats and insects. They can even walk on water. Now roboticists at the University of Washington have built a school of three robotic fish that swim and communicate wirelessly with one another using sonar signals. So far the fish are swimming happily in a laboratory tank, but researchers plan to build 20 of the aqua bots and unleash them in the Puget Sound next year to help track fish and whale migration, and contaminants in the water.
Robot fish have been around for a few years (pictured above in the London Aquarium, from 2005), but the UW invention is a milestone because it's the first group of robofish that can school through active communication. Biological fish form dazzling schools by communicating through their lateral lines and in a sense the bots do the same thing, only their communication is based on sonar. The fish are also equipped with 3-d compasses so they know where they are in the water, and pressure sensors to keep track of how deep they dive.
Admittedly they're not as sexy as their biological cousins, but videos of them swimming here show they make spooky stand-ins for the real thing.