Pliant Energy Systems recently showed off a robot with a novel propulsion system. Instead of using wheels, rotors, or even legs to move, Pliant's bot uses a set of actuators attached to flexible "fins" that resemble a cuttlefish, allowing it to move over almost any surface. In the video here, the researchers show it off on sand, ice, and water. Plaint envisions militaries using the robot for resupply or reconnaissance missions, and also seems to think it would excel at underwater wildlife observation. While they haven't given the underwater robot any autonomy with machine learning, like iBubble, I'm sure it's only a matter of time.