Researchers at Northwestern University have created a robot that mimics the movements of a knifefish
, a creature that deftly swishes its lone fin in a ribbon-like motion to swim vertically. According to Fast Company, professor Malcolm MacIver noticed the curious way in which a knifefish he had in his aquarium tank would shoot upward. After studying the fish, MacIver and his colleagues discovered that it used different fin movements to swim in different directions. To move horizontally, the fish moves either the front or the back of its fin, independently of each other, one way or the other. But to move vertically, the researchers discovered, the knifefish simultaneously moves the front and back of its fin, creating two waves of force that meet in the middle to propel the fish vertically.
Of course, MacIver and his team didn't want to just learn about the fish and how it moved; they wanted to replicate what the fish can do underwater. So, the researchers spent $200,000 designing a knifefish robot, dubbed GhostBot. The underwater 'bot has 32 independently moving parts that wiggle its ribbon fin, and replicate the movements of a real knifefish. One day, the agile GhostBot could be used for rescue operations, studying coral reefs, or -- God forbid that it's ever needed -- repairing a damaged underwater oil well. Check out a video of the GhostBot after the break.