The first robo-fish was MIT's Charlie the Tuna. According to the MIT website:
In summer 1995 the researchers' original creation, patterned after a bluefin tuna, took its maiden swim down the MIT Testing Tank.That swim and others since have been exciting, reinforcing the engineers' belief that the Lycra-sheathed robot could become an important tool toward understanding the physics of swimming and more. The "robotuna" project began in 1993 with the overall goal of developing a better propulsion system for autonomous underwater vehicles.
Sure, it looks pretty old fashioned and Captain Nemo-like. But progress marches on.
Late last year, from Britain:
October 7, 2005 (BBC)—This week the London Aquarium unveiled the newest "species" to join its collection: robo-carp.This is a very pretty looking machine, one of the best looking robots.
Computer scientists at the University of Essex in the U.K. developed the self-guided robot fish, seen here swimming in the aquarium. The designers say it is the smartest such robot yet created—the fish uses artificial intelligence and built-in sensors to avoid obstacles and respond to environmental changes.
The fish's battery lasts for up to five hours, though the scientists hope to one day program it to search for and access a recharging station when it runs low.
And now, from clever engineers in Japan, we get this:
According to the very interesting "Pink Tentacle website:
“Robo-carp” rehearses for public debut
April 14 2006: The robotic koi carp unveiled last month by a group of Hiroshima engineering companies (led by Ryomei Engineering) is scheduled to make its first public appearance this weekend.
It was spotted during rehearsal in a large tank at Miyajima Aquarium (in Hatsukaichi city in Hiroshima prefecture), practicing its trademark moves of spinning around, treading water, and swimming in reverse.
The robot appeared to be getting along will with the other fish in the tank — an alligator gar and three endangered pirarucu that measure over 2 meters in length. “It looks like a robot, but it behaves like a real fish,” said one surprised onlooker.