December 25, 2020 by Luke James
Researchers at the University of Glasgow have developed a new type of solar-powered e-skin that uses light to mimic the human sense of touch. The scientists claim that the ‘skin’ could hold the potential to truly revolutionise the field of affordable prosthetics by using its light-capturing cells to mimic touch.
In the Glasgow University’s paper, published in IEEE Transactions on Robotics, the researchers describe how a robotic hand wrapped in their flexible solar e-skin is capable of interacting with physical objects, enabling it to sense the shape and proximity of objects in its grasp.
By using calculations based on the level of light received by the device’s solar cells and LEDs, the researchers have been able to eliminate the use of dedicated touch sensors (commonly found in conventional prosthetics) that are expensive and power-hungry.
In addition to the above-mentioned light-based calculations, the technology’s standard LEDs in-between the solar cells bounce infra-red light off nearby objects to measure distance.
When combined, the two forms of light measurement give the skin a sense of ‘touch’ that could massively enhance prosthetic limbs and robotics. During lab-based testing, the research team was able to use a prototype robotic hand to grasp objects placed in front of it.
Said Professor Ravinder Dahiya, the research team’s leader at Glasgow’s James Watt School of Engineering: “It’s one step closer to a completely self-powered prosthetic wrapped in flexible skin made from relatively inexpensive components”. Dahiya went on to add that the sensing capabilities built into the skin could enable it to ‘see’.
The researchers are so confident in their e-skin, in fact, that they claim—with further refinements—it could identify approaching objects before they even make physical contact.
The University of Glasgow’s overview of its flexible electronic skin. Pictured: the device’s main components and their integration in the 3D-printed robotic hand, along with a block diagram that outlines the device’s three subsystems: actuation, sensing, and power management. Image Credit: the University of Glasgow via the IEEE.
Professor Dahiya says that the lack of sensors in the e-skin means that it requires “no conventional power source.” He added that the skin itself is the source of energy capable of powering the hand and any devices attached to it.
“It’s one step closer to a completely self-powered prosthetic wrapped in flexible skin made from relatively inexpensive components. The sensing capabilities built into the skin could even lead to a skin that can ‘see’—further refinements could help the skin identify approaching objects even before they make contact,” he explains.
The team plans to experiment further with their e-skin: for example, by adding supercapacitors so that the skin can continue operating in the absence of daylight.
More information on the University of Glasgow’s prosthetics technology can be read here on Electronics Point.
