Matthew Humphries for PCMag:  Catching a fish can be tough, even if you are just trying to net a goldfish in a small tank. That's because the fish spots the danger and makes a swim for it. But what if you didn't need a net because you're controlling an invisible grabbing robot?

That's what Xuanhe Zhao, a professor of mechanical engineering at MIT succeeded in creating, but its applications go way beyond catching and releasing fish unharmed.

The robot is constructed of a transparent hydrogel, which is strong and durable but mostly made of water. As the video below explains, each arm of the robot is constructed from 3D-printed hollow cubes of hydrogel, which are then linked together. By injecting water using a syringe it's possible to make the arms curl and uncurl quickly in a grabbing motion.  Cont'd...