Here’s SoFi, the world’s first robotic fish. SoFi, short for soft robotic fish, looks like a fish and swims like a fish, but it actually is the most versatile robot of its kind. Created at MIT’s computer science and AI lab CSAIL, SoFi (pronounced Sophie) is 18.5 inches long, weighs 3.5 pounds, and can stay underwater at depths of up to 60 feet for 40 minutes. SoFi is built with printed 3D plastics and has a built-in buoyancy tank full of compressed air. A hydraulic actuator pumps water in and out of a pair of chambers to make SoFI go,…