Watch This Squishy, See-Through Robot Grab a Live Goldfish

Squishy, nearly transparent robots that flap, squeeze and kick when pumped with water could be the next underwater spies, at least when it comes to sneaking up on aquatic life. The researchers, led by engineer Xuanhe Zhao and graduate student Hyunwoo Yuk, created a series of the transparent robots from a rubbery material called hydrogel, including a fin-like bot that can flap back and forth, a "limb" that can kick, and a hand-shaped structure that can squeeze and let go. Because the material is composed mostly of water, the resulting robots could also have biomedical applications, the researchers said.