Synthetic skin capable of touch sensitivity could make smart prosthetic hands more useful for amputees
Scientists have developed a new type of robotic skin that can harvest energy from the sun and is more sensitive to touch than a human hand.
The synthetic skin is made from “wonder material” graphene, which despite being just a single atom thick, is stronger than steel, electrically conductive, and transparent.
Engineers from the University of Glasgow have used the synthetic skin to cover prosthetic hands, enabling the prosthetics to make very sensitive pressure measurements.
This means they can to perform challenging tasks like gripping soft materials, which other prosthetics can struggle with, and represents a further step towards the development of prosthetic limbs or robots with a sense of touch.
“Human skin is an incredibly complex system capable of detecting pressure, temperature and texture through an array of neural sensors which carry signals from the skin to the brain,” said Dr Ravinder Dahiya, from the University of Glasgow’s School of Engineering.
“Skin capable of touch sensitivity opens the possibility of creating robots capable of making better decisions about human safety.
“A robot working on a construction line, for example, is much less likely to accidentally injure a human if it can feel that a person has unexpectedly entered their area of movement and stop before an injury can occur.”
Teams around the world are working to develop flexible versions of synthetic skin that can feel by mimicking the different kinds of sensory receptors found in human skin, but powering such systems is a challenge.
Dr Dahiya claims that graphene’s optical transparency, which allows around 98% of the light which strikes its surface to pass directly through it, which makes it ideal for gathering energy from the sun to generate power.
The synthetic skin requires just 20 nanowatts of power per square centimetre, which is easily met even by the poorest-quality photovoltaic cells currently available on the market.
Although currently energy generated by the skin’s photovoltaic cells cannot be stored, the team is already looking into ways to divert unused energy into batteries, allowing the energy to be used as and when it is required.
“The other next step for us is to further develop the power-generation technology which underpins this research and use it to power the motors which drive the prosthetic hand itself,” Dr Dahiya said.
“This could allow the creation of an entirely energy-autonomous prosthetic limb.”
Smart prosthetic hands can already reproduce many mechanical properties of human limbs. Giving them a skin-like sense of touch would make them even more useful for amputees.
The team’s paper, titled “Energy Autonomous Flexible and Transparent Tactile Skin”, is published in Advanced Functional Materials.
Source of the Article: mirror.co.uk