Engineers have developed a new way of harnessing the sun’s rays to power “synthetic skin” that they hope can be used to create advanced prosthetic limbs capable of returning the sense of touch to amputees.
The researchers from the University of Glasgow had previously created “electronic skin” for prosthetic hands made from graphene, a highly flexible form of graphite that is only a single atom but stronger than steel.
The new skin is more sensitive and uses natural energy from the sun’s rays instead of batteries currently used by similar materials.
Graphene’s optical transparency, the researchers explain, allows around 98 percent of the light that strikes its surface to pass directly through it, making it ideal for gathering energy from the sun to generate power.
Dr. Ravinder Dahiya, from the University of Glasgow’s School of Engineering, and his colleagues from his Bendable Electronics and Sensing Technologies (BEST) group detail the research in the journal Advanced Functional Materials.
“My colleagues and I have already made significant steps in creating prosthetic prototypes which integrate synthetic skin and are capable of making very sensitive pressure measurements,” he said in a statement. “Those measurements mean the prosthetic hand is capable of performing challenging tasks like properly gripping soft materials, which other prosthetics can struggle with.”
The technology also opens the possibility of creating robots capable of making better decisions about human safety, he adds.
“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,” Dahiya said.
The new skin requires 20 nanowatts of power per square centimeter, equivalent to the lowest-quality solar cells currently available. The researchers are looking into ways to divert extra energy into batteries for future use.
“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,” Dahiya said. “This could allow the creation of an entirely energy-autonomous prosthetic limb.”