Pressure-sensitive robotic "skin" lights up when touched, and brightens more the harder it is pressed. UC Berkeley

In the future, holding hands with a robot won’t have to feel like gripping a cold steel claw. Scientists are working on new designs for robot skin that will allow machines to feel their environment around them, the same way that we filter the world through our fingertips. Some models of robot skin are designed to mimic our own, but others sacrifice realism for something a bit flashier.

On Sunday, in the journal Nature Materials, researchers from the University of California, Berkeley and Michigan State University unveiled their design for a special kind of robotic skin that lights up when touched. The illumination comes from an arrangement of special LED lights sandwiched between plastic and pressure-sensitive rubber. Plus, the light gets brighter the more pressure is applied, according to the authors. Here's a video of the skin in action:

“Instead of using the material to create bodysuits for Burning Man or other illuminated party tricks, scientists suggest that it might be used for smart wallpapers, health-monitoring devices, or in robotics,” Wired wrote. “The type of interactive pressure sensor developed by the Berkeley scientists could also be useful in artificial skin for prosthetic limbs.”

Having some kind of touch feedback in place for a replacement leg, arm or hand could go a long way toward helping amputees regain use of that limb. Imagine a guitarist that’s lost a few fingers given replacement digits with this kind of skin. With prosthetic fingers that can glow softer or brighter under varying pressures, they might be quicker to take up their instrument again!

“I could also imagine an e-skin bandage applied to an arm as a health monitor that continuously checks blood pressure and pulse rates,” study co-lead author Chuan Wang said in a statement.

The light-up skin could also help robots interact with their environment even better. A robotic undersea drill could have light displays that indicate pressure changes as it searches for oil and gas reserves; a robotic nanny might be able to respond to its own light-emitting pressure feedback, allowing it tend to babies without crushing them.

Scientists are also working to increase the sensitivity of robotic skin models to match our own. In April, a group of researchers led by Georgia Tech engineer Zhong Lin Wang published a paper in Science describing their new model for robotic skin, which contains an array of nanowires made up of zinc oxide. The nanowires are what’s called “piezoelectric”; when force is applied, an electric charge is generated.

In the paper, Wang and his colleagues said that the sensitivity was about two to three times more improved than the most-advanced previous model. The density and sensitivity of the sensors “is comparable to that of the skin of a human finger,” Zhong Wang says, according to the MIT Technology Review.

SOURCE: Wang et al. “User-interactive electronic skin for instantaneous pressure visualization.” Nature Materials published online 21 July 2013.