Super-stretchy ‘octopus skin’ will let robots flex and change colour

Imagine a wearable smartphone that could bend and stretch with your body, all while displaying a glittering array of colours.

That’s a possible eventual use of new octopus-inspired robotic “skin” from researchers at Cornell. It can stretch to six times its original dimensions while still emitting light. Described in a study published Thursday in Science, this super-stretchy skin is also designed to give soft robots the ability to change colour and display information based on input from their sensors.

Soft robots have been gaining popularity among engineers over the past few years. Made without the stiff mechanical components of a traditional robot, they’re much better at bending and squeezing into tight spaces.

But for now, most soft robot prototypes have a lot of hard robot baggage. Engineers have to come up with new ways to build basic components such as batteries, circuit boards and displays using flexible materials.

“The clock radio in your car works in the same way [as the new octopus skin], but isn’t made with material that stretches,” lead study author Robert Shepherd, assistant professor of mechanical and aerospace engineering at Cornell, told The Washington Post. The idea for the skin came about when Shepherd challenged his graduate students to design devices that overcame the rigidity of traditional components.

The students were inspired by cephalopods, which are able to change their skin colour and also have a degree of squishiness that any soft robotics engineer would covet. But mimicking the mechanism that octopods use would have been too complicated: Those animals change colour by absorbing and reflecting light, and the team decided it would be easier to design light emitting components that could handle stretching.