It’s time to roll up your sleeves for the next advance in wearable technology – a fabric armband is actually a touch panel. in ACS NanoResearchers say they have created a method that makes it easier to play video games, draw cartoons and sign documents. This proof-of-concept silk wristband turns a person’s forearm into a keyboard or drawing board. The touch-responsive three-layer material interprets what a user draws or writes and turns it into images on a computer.
Computer trackpads and electronic signature capture devices seem to be everywhere, but they are not widely used in wearable devices. The researchers proposed making flexible, touch-responsive panels out of transparent, electrically conductive hydrogels, but these materials are sticky, making writing on them difficult and irritating to the skin. Therefore, Xueji Zhang, Lijun Qu, Mingwei Tian, and colleagues wanted to incorporate a similar hydrogel into a comfortable fabric sleeve for drawing or playing games on a computer.
The researchers sandwiched a pressure-sensitive hydrogel between layers of woven silk. The top piece was coated with graphene nanosheets to make the fabric electrically conductive. Connecting the sensor pad to the electrodes and data collection system produced a pressure-responsive pad with rapid real-time sensing when a finger slid over it, typing out numbers and letters. The device is then integrated into an arm-length silk wrap with a touch-responsive area on the forearm. In the experiments, a user controlled the orientation of blocks in a computer game and drew colorful animations in a computer drawing program from an armband. Researchers say a proof-of-concept wearable touchpad could inspire the next generation of flexible keyboards and wearable drawing boards.