Researchers created glowing skin for robots that can be stretched to more than six times its original size and even sense touch. This artificial skin, developed by a team of scientists from Cornell University, was inspired by the flexible bodies and color-changing organs of squid and octopuses.
The research team, led by Chris Larson, developed this superstretchy material using a hyperelastic, light-emitting capacitor (HLEC) embedded in a matrix of silicone. The capacitors respond to changes in pressure and can, therefore, act as sensors. Furthermore, the capacitors contain zinc sulfide that, with the addition of different transition metals, allows them to change color. For example, adding copper creates a blue light and magnesium creates yellow. When stretched, the electrical field of the artificial skin increases and emits more light.
The hope, researchers said, is to use this artificial skin in the development of health care robots that can display a patient's temperature and pulse - and even react to their mood.
"This material can stretch with the body of a soft robot, and that's what our group does," said Rob Shepherd, assistant professor of mechanical and aerospace engineering, in a news release. He added that the material has two key properties: "It allows robots to change their color, and it also allows displays to change their shape."
Previously, artificial skin was limited to being stretched to about only 120 percent of its original size. This new skin, however, is able to maintain its display while being stretched up to 480 percent - four times more than any previous luminescent "skin," said researchers.
"We can take these pixels that change color and put them on these robots, and now we have the ability to change their color," Shepherd explained. "Why is that important? For one thing, when robots become more and more a part of our lives, the ability for them to have emotional connection with us will be important. So to be able to change their color in response to mood or the tone [atmosphere] of the room we believe is going to be important for human-robot interactions."
So far researchers have only created a three-chamber robot with the artificial skin on top and inflatable layers below that allow for worm-like movement. In the future, however, researchers will have to make the panels more luminous, higher-resolution and thinner in order for them to be used more widely.
Their findings were recently published in the journal Science.
