Their underwater robot is essentially a copy of an octopus’s head, which expands when it is filled with water and squirts it out through a nozzle at the rear. This robot has no tentacles but instead, the team fitted small fins to the rear to stabilise its movement through the water.

So the robot is roughly ellipsoidal in shape, measuring 27 centimetres in length and is 5 times longer than it is wide. It is created by stretching a rubber membrane over a set of polycarbonate ribs. Weymouth and co chose this shape because of its ability to glide many body lengths through water.

The results are extraordinary. As the water starts to squirt out of the nozzle, the robot begins to accelerate. However, it moves little during the first half second or so since its bluff body shape prevents efficient progress.

But then, as the robot shrinks, it accelerates rapidly. And here’s the thing: Weymouth and co say that its maximum acceleration is 14 body lengths per second squared and that it reaches speeds of 10 body lengths per second.

That’s unprecedented for an underwater robot. “The robot is found to experience extraordinary speeds,” say Weymouth and co.

Words cannot describe how cool this is!