Researchers from China's Qingdao University and Shenzhen University have developed a graphene-based proof-of-concept for a skin-friendly and wearable textile-based touch panel that converts a person's forearm into a keyboard or sketchpad. The three-layer, touch-responsive material translates what a user sketches or types into computer pictures.
Computer trackpads and electronic signature capture devices are not common in wearables. Researchers have proposed constructing flexible touch-responsive panels out of clear, electrically conductive hydrogels, but these materials are sticky, making writing on them difficult and uncomfortable for the skin. As a result, the research team sought to combine a comparable hydrogel into a comfortable fabric sleeve for drawing or playing computer games.
The researchers sandwiched pressure-sensitive hydrogel between layers of knit silk. To make the fabric electrically conductive, the top piece was covered in graphene nanosheets. When a finger slides over the sensing panel, it produces a pressure-responsive pad with real-time, rapid sensing when connected to electrodes and a data collection system.
The device was embedded in an arm-length silk sleeve with a touch-sensitive region on the forearm. In experiments, a user used an armband to control the movement of blocks in a computer game and to draw vivid cartoons in a computer drawing application.
According to the researchers, this wearable touch panel proof-of-concept could inspire the next generation of flexible keyboards and wearable sketchpads.