An invisible robot arm that is virtually undetectable underwater has been developed.

Inspired by glass eel larvae it’s made of a polymer gel that’s over 90% water by weight and both light and sound waves pass through it. This makes it nearly undetectable to those around it, as the engineers at the Massachusetts Institute of Technology who created it proved with a video that showed it stealthily grabbing a fish.

The finished product is incredibly soft and squishy so it can grab living things without hurting them, and the hydraulics of the soft robots are controlled by pumping different amounts of water at specific internals through small channels inside them, which spark various actions, including the ability to grab.

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