A ‘supersmart’ artificial skin has been revealed that could give patients back a sense of touch. Researchers in South Korea say their skin is extremely similar to human skin. It is stretchy, like real skin, and even has a built-in heater so it feels like living tissue. It can sense pressure, temperature, and humidity, and researchers tested the artificial skin on a prosthetic hand, and found the wearer could even sense if a diaper was wet or dry.
‘The prosthetic hand and laminated electronic skin could encounter many complex operations such as hand shaking, keyboard tapping, ball grasping, holding a cup of hot or cold drink, touching dry or wet surfaces and human to human contact,’ they write in the paper, which was published today in Nature Communications. The bulk of the new skin is composed of a flexible, transparent silicone material called polydimethylsiloxane — or PDMS.
Embedded within it are silicon nanoribbons that generate electricity when they’re squished or stretched, providing a source of tactile feedback. They can also sense whether an object is hot or cold. The humidity sensors are made up of capacitors, and were tested using a diaper. Researchers had the prosthetic hand prod various diapers, and it turned out it was able to distinguish between wet and dry diapers. The team also decided that to give the feel of real skin, the skin needed to be warm. ‘For prosthetic devices and artificial skin to feel natural, their temperature profile must be controlled to match that of the human body,’ the authors write.
To test whether or not the skin maintains a steady 98 degrees Fahrenheit, the researchers put the hand on a plastic baby doll and measured the amount of heat the hand transferred to the doll. By adjusting the shape of the silicon nanoribbon patterns, the researchers can adjust how stretchy the skin is. For regions where the skin doesn’t need to stretch, such as the fingertips, the nanoribbons are packed in a tight linear pattern to maximize sensitivity. For areas like the wrist, which need more flexibility, the nanoribbons form a more loopy pattern, allowing for more room to expand by up to 16 percent. ‘This is an important demonstration of the applications of stretchable electronics,’ said Bao.
‘Currently we have demonstrated our system in small animals. But the next step is to continue the development for the advanced version, such as a complicated array of sensors that emulate real mechano- and thermo- sensory functions of the human,’ Kim Dae-Hyeong, co-author of the study , told CBS.
HOW IT WORKS
The bulk of the new skin is composed of a flexible, transparent silicone material called polydimethylsiloxane - or PDMS. Embedded within it are silicon nanoribbons that generate electricity when they’re squished or stretched, providing a source of tactile feedback. They can also sense whether an object is hot or cold. Humidity sensors are made up of capacitors. Thermal actuators control how much heat the artificial skin emits.
sources: engadget, abc.net, cnet, CBS