Engineers at the University of Glasgow have developed an artificial skin with tactile sensors for prosthetics and robotics. It is flexible and solar powered, which is enabled by the use of graphene.
The latest developments in artificial skin have made it possible to emulate the sensation of touch. However, many of these surfaces rely on an external battery to operate sensors, making them bulky and unlikely to be used for limb replacement or robotics.
Graphene to Power Flexible Tactile Skin
A team of engineers at the University of Glasgow has tackled the external energy problem by developing a solar-powered tactile skin that could provide haptic feedback to amputees as well as robots. For the Deus Ex fans out there, this could be the start of the augmented revolution.
Dr. Ravinder Dahiya, director of the Electronics Systems Design Centre (ESDC), and his teammates from the Bendable Electronics and Sensing Technologies group (BEST) have been working on tactile artificial skins for a long time. Their latest breakthrough stemmed from the challenge to power these skins, and obviously, they bet on solar power.
Limb replacement could be a thing soon with Dr. Dahiya's solar-powered skin.Click To Tweet
“The real challenge was,” said Dr. Dahiya, co-author of the study published in Advanced Functional Materials, “how can we put skin on top of photo-voltaic and yet allow light to pass through the skin?”
And there’s no other material that can compete with graphene in that regard. Electrically conductive, and 100 times harder than steel, graphene is transparent and lets up to 98% of light to pass through.
Ambient Energy e-Skin for Limb Replacement, Robotics, and Wearables
Researchers put a single-layer of graphene under the tactile layer of the electronic skin that is covered with sensors. Integrated into the graphene layer, photovoltaic cells harvest light energy to power the sensors. Since this e-skin requires ultra low power (20 nanowatts per square centimeter) to function, the least-efficient of photovoltaic cells available on the market could provide enough energy.
This solar power harvesting method is still a prototype, and the team is working to further develop it to power the motors of a prosthetic limb itself and make it entirely energy-autonomous.
Tactile, solar-powered artificial skins will have better portability and operating time, making them practical to integrate with prosthetic limbs and restore the sense of touch to amputees. The promise of a true limb replacement rather than just a prosthetic could mitigate the challenge of disability.
In the future, these skins could help robots perceive temperature, pressure, and texture/terrain. The technology could also be used to make precise medical wearable devices, as the UG team received funds from the Scottish Funding Council to explore this path.