Engineers from the University of Glasgow have published the results of their research into developing an electronic skin that can learn to feel ‘pain’.
The paper, titled ‘Printed Synaptic Transistors based Electronic Skin for Robots to Feel and Learn’ published in Science Robotics, highlights artificial skin with a new type of processing system based on synaptic transistors, which mimics the brain’s neural pathways in order to learn. It means, a robot hand using the smart skin “shows a remarkable ability to learn to react to external stimuli”.
In the paper, the researchers describe how their new form of electronic skin draws inspiration from the way in which the human peripheral nervous system interprets signals from skin, processing input from the point of contact and reducing the sensory data sent to the brain so that it receives only the vital information needed to respond with an appropriate bodily reaction.
The researchers printed a grid of 168 synaptic transistors made from zinc-oxide nanowires directly onto a flexible plastic service, then 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 electrical resistance, designed to mimic sensory neurons in the human body. A circuit built into the skin acts as an artificial synapse and reduces the input into a spike of voltage, with frequency varying according to the level of pressure applied. The researchers used the varying output of the voltage spike to teach the skin how to respond appropriately to simulated pain, triggering the robot hand to react and recoil.
This development is the latest breakthrough in flexible and stretchable printed surfaces from Glasgow’s Bendable Electronics and Sensing Technologies (BEST) Group, led by Professor Ravinder Dahiya.
Co-author and member of BEST, Fengyuan Liu, said, “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.”
The research was supported by funding from the Engineering and Physical Sciences Research Council.
