Now you see it, now you don’t.
Inspired by cephalopods like octopuses and cuttlefish, which change their skin textures for camouflage, researchers fabricated a stretchy material that inflates into various 3-D shapes and flattens back out. These shape-shifting “skins,” described in the Oct. 13 Science, could someday help robots don quick disguises.
Scientists have previously taken inspiration from cephalopod camo to fashion material that changes colors in response to changes in lighting (SN: 10/4/14, p. 5). The new material is modeled after papillae — the tiny bumps that cephalopods raise and lower on their skin to mimic the textures of coral, seaweed and other surroundings, explains study coauthor James Pikul, an engineer at the University of Pennsylvania. Each pad of synthetic skin (shaped like a whoopee cushion) is made of silicone rubber with a specific pattern of stiff, fabriclike mesh embedded in its top layer. When researchers pump air into this sleeve, the silicone stretches but the fibrous material doesn’t, forming a particular shape.
Researchers could create pop-ups of many different configurations by changing the layout of rigid material implanted in the silicon. For this study, the engineers fabricated skins that assumed the form of a succulent, or matched the shape of surrounding stones in a rock bed. These designs are “excellent camouflage,” says Cecilia Laschi, a bioroboticist at Sant’Anna School of Advanced Studies in Pisa, Italy. “They show a very strong similarity with the surroundings.”
Robots wearing such camouflaging skins could covertly observe animals in their natural habitats, or help with military operations in hostile territory.
IN AND OUT New synthetic skins inflate into 3-D configurations (like this succulent bloom) and flatten back into 2-D sheets in a matter of seconds. “Theoretically, you could do this really, really quick — milliseconds,” says study coauthor James Pikul. It’s just a matter of pumping air in and out faster. J.H. Pikul et al/Science 2017