First up, the crab, which is was built by the Korean Institute of Ocean Science and Technology and goes by Crabster CR200. The beast was designed to walk the ocean floor in strong currents and treacherous waters.When CNN wrote about it last April, researchers said their chief challenge was getting the crab to go faster. At the time, it traveled 10cm per second. Now researchers have it scooting along at 25cm per second, or .5 knots. Just look at it go.
This is actually record time for an underwater walking robot. But on the other end of the spectrum is a swimming robot that uses jet propulsion, much like an octopus.
This 3-D-printed, 10-inch device fills up with water and then forcefully expels it, using the energy of the expulsion to propel itself forward — it covers ten times its body length in less than a second. The highly efficient robot has a polycarbonate skeleton covered in a plastic balloon with no other moving parts.
Some, like a commenter on the below YouTube video, have quibbled with calling it a robot, since it doesn’t have mechanical components. The University of Southampton’s Gabe Weymouth, who was a part of the team that designed the robot, replied to the criticism, writing, “Soft-robotics is an emerging field and there were some cool robots using the shape-change concept, but they were slow. We built this single-purpose version to show that it could be effective at high speed. And the performance is remarkable."
If the tortoise and the hare was too close a match for you, you’re going to love this hypothetical race between an underwater robotic crab and an underwater robotic octopus. Both of these machines represent significant steps forward for underwater walking and swimming robots. But how do they measure up against each other?