Stanford engineers have created a plastic "skin" that can detect how hard it is being pressed and relay the information via an electric signal to the brain.
The material is constructed from two layers with the top layer acting as a sensing mechanism and the bottom layer acting as the circuit to transport electrical signals and translate them into biochemical stimuli compatible with nerve cells.
The sensor in the top layer has been designed to detect pressure in the same range as human skin in order to differentiate, for example, a light finger tap from a firm handshake.
Billions of carbon nanotubes are embedded into the plastic. Putting pressure on the material squeezes the nanotubes closer together enabling them to conduct electricity. The higher the pressure, the more electricity can flow through the nanotubes, with the resulting signal emulating stronger pressure.
The researchers then engineered a line of neurons to simulate a portion of the human nervous system.
They translated the electronic pressure signals from the artificial skin into light pulses, which activated the neurons, proving that the artificial skin could generate a sensory output compatible with nerve cells.
Stanford professor Zhenan Bao has spent 10 years developing artificial skin which includes the ability to flex and heal.
"This is the first time a flexible, skin-like material has been able to detect pressure and also transmit a signal to a component of the nervous system," said Bao.
"We have a lot of work to take this from experimental to practical applications, but after spending many years in this work, I now see a clear path where we can take our artificial skin."
In the future, the 17 man team that led the research envisions developing different sensors in order to detect differences in texture, for example between corduroy and silk, or a cold glass of water from a hot cup of coffee.