MIT gel robot is nearly invisible underwater, fast enough to grab fish

Researchers at MIT have created a new robot using hydrogel that, when placed underwater, is nearly invisible to the naked eye. Despite being made of transparent gel and powered by water, the robot is capable of reasonably fast movements, including grabbing a live fish, holding on to it, and then releasing it safely back into the water. Such a precise but gentle touch could one day have many applications, including surgical assistance.

Hydrogels are made primarily from water and are described as being both wet and soft. In the case of the video below, researchers show a robotic claw made with this hydrogel that is able to maneuver in water and grasp, in this case, a fish using a curling motion.

While the human impression of robots is that they're made of metal, many researchers — including those outside MIT — have pointed toward the need for soft artificial skins and other materials for safer interactions with humans. In this case, the researchers, including MIT's Xuanhe Zhao and Hyunwoo Yuk, have created a variety of hydrogels that may be suitable.

In addition to developing different varieties of hydrogels, the team has also developed ways to fix the gel onto surfaces that include metal, glass, rubber, and ceramic. The hydrogel is said to bond very well with the materials, being resistant to peeling despite its soft nature. We may one day see such materials used on robots that aid in surgical procedures, where delicacy and softness is as necessary as precision and durability.