Artificial limbs and prosthetic devices have come a long way in enabling amputees to be independent. However, even with technology allowing them to control artificial limbs -- either through input mechanisms or advanced systems directly wired to their nervous systems -- they still lack the ability to feel real pressure or fluctuations in temperature.
A team of researchers from the United States and South Korea has been developing a new kind of artificial skin that will allow people who use prosthetic limbs to feel heat, pressure and moisture. The polymer that covers the sensors will even feel like warm human skin to anyone who touches it.
The breakthrough is made possible using stretchable silicon nanoribbons. These nanoribbons are thin and keep layers of different types of sensors, which are durable but can also bend and flex with greater ease. The technology also transmits a large amount of data.
According to Roozbeh Ghaffari, one of the contributing researchers, the snakelike formations that the sensors form on the nanoribbons enable them to stretch more while covering a wider area for data input on the skin. The wider coverage also allows for more information to be relayed to the nerves and brain.
"If you have these sensors at high resolution across the finger, you can give the same tactile touch that the normal hand would convey to the brain," he said.
The researchers hope that their work will one day allow amputees to have restored sense of touch, especially in their hands, in order to pick up objects without crushing or dropping them, know when a cup of coffee is too hot, or even gently feel their children's foreheads when they have a fever.
Although the development of the silicon nanoribbons is a huge step forward in artificial skin technology, the team says they still have many more hurdles to overcome and lab tests to perform on larger animals before the artificial skin can be offered for commercial use.
The team published their findings in the Dec. 9 issue of Nature Communications.