This Electronic Skin Can Feel Pain

This Electronic Skin Can Feel Pain
Image: TriStar Pictures, Columbia TriStar Films AB

Smart robots with human-like sensitivity. No, it isn’t a plot for an upcoming sci-fi movie, it’s new research out of Glasgow. Electronic skin that is capable of feeling pain. Woah.

A team of engineers from the University of Glasgow developed the electronic skin with a new type of processing system based on ‘synaptic transistors’, which mimics the brain’s neural pathways in order to learn.

The potential? An electronic skin which can learn from feeling ‘pain’ could help create a new generation of smart robots. Ones with human-like sensitivity.

“We all learn early on in our lives to respond appropriately to unexpected stimuli like pain in order to prevent us from hurting ourselves again,” Professor Ravinder Dahiya, of the University’s James Watt School of Engineering, said.

“Of course, the development of this new form of electronic skin didn’t really involve inflicting pain as we know it. It’s simply a shorthand way to explain the process of learning from external stimulus.”

The team’s electronic skin is capable of ‘distributed learning’ at the hardware level. One which doesn’t need to send messages back and forth to a central processor before taking action.

Instead, it greatly accelerates the process of responding to touch by cutting down the amount of computation required.

“We believe that this is a real step forward in our work towards creating large-scale neuromorphic printed electronic skin capable of responding appropriately to stimuli,” Dahaiya added.

So how did they approach electronic skin?

Scientists have been working for decades to build artificial skin with touch sensitivity. One widely-explored method is spreading an array of contact or pressure sensors across the electronic skin’s surface. This allows it to detect when it comes into contact with an object. You know, like touch.

Data from the sensors is then sent to a computer to be processed and interpreted. The sensors typically produce a large volume of data which can take a long time to be processed. This introduces delays in ‘reaction’. Sort of like you flinching 30 seconds after a pin pricks you. The method the researchers used mimics our ‘normal’ response more. As soon as human skin receives an input, the peripheral nervous system begins processing it. A reaction is then felt immediately.

To build an electronic skin, the researchers printed a grid of 168 synaptic transistors. They were made from zinc-oxide nanowires on a flexible plastic surface. Then, they connected the synaptic transistor with the skin sensor present over the palm of a human-shaped robot hand.

When the sensor is touched, it registers a change in its electrical resistance. A small change corresponds to a light touch, and harder touch creates a larger change in resistance. This mimics the way sensory neurons work in the human body.

“In the future, this research could be the basis for a more advanced electronic skin which enables robots capable of exploring and interacting with the world in new ways. Or building prosthetic limbs which are capable of near-human levels of touch sensitivity,” Fengyuan Liu, a member of the BEST group and a co-author of the paper, added.

You can read more about the electronic skin here.