UNIST develops smart artificial skin
Researchers at UNIST, a science and technology university based in Ulsan, Korea, have long been interested in the technology of artificial skins. Although previous studies have introduced an assortment of electronic skin (e-skin) elements, none of them were able to detect both pressure and heat with a high degree of sensitivity.
A team affiliated with UNIST has now come up with a new form of e-skin that may share the capabilities that human skin has. Through this study, the team introduced human skin-inspired multimodal e-skins based on flexible and microstructured ferroelectric films, which enhance the detection and discrimination of multiple spatiotemporal tactile stimuli, such as static and dynamic pressure, temperature, and vibration.
According to Prof Hyunhyub Ko, school of energy and chemical engineering at UNIST, “this is the first time in history that someone presents an e-skin that is capable of sensing so many different kinds of stimuli.” The functionalities of human skin are mimicked by elastomeric patterns (texture), piezoresistive (static pressure), ferroelectric (dynamic pressure and temperature), and interlocked microdome arrays (tactile signal amplification).
Prof Ko and his team placed a soft rigid film over bumpy plastic-and-graphene sheets about the thickness of a few layers of saran wrap. The touching of the e-skin pressed electrodes on the bumpy sheets together, causing current to flow through the device, which was hooked up to a machine that measures electric signals. Electric current was also observed when heating the e-skin, showing that it could also sense temperature. “Though the technology has yet to be tested outside the lab, the work takes a big step toward adding a sense of touch to prosthetic limbs and other wearable medical devices,” concludes Ko.