The Sensor Hosting Autonomous Remote Craft (SHARC), also known as Wave Glider, harvests wave and solar power for energy so it can roam the seas almost indefinitely. t can be dispatched to hard to reach places, and can operate for nearly an entire year without refuelling. On the surface, they look like black surfboards, but inside is a computer system that can collect data about the ocean. Beneath, attached by a long cord, is a sub with six fins that uses the motion of the waves to propel the robot forward. There’s also a solar-powered thruster in case it needs to go faster. So far, these robots have collectively travelled more than 2.7 million nautical miles.