This Skin-Friendly Silk and Hydrogel Wearable Turns Your Arm Into a Touch-Sensitive Input Device
A combination of hydrogel and silk, this touch-responsive armband can serve as a keyboard, game controller, or doodle pad.
Researchers from Qingdao University and Shenzhen University have developed a wearable sleeve that doubles as a touch-sensitive input device — demonstrating its use for everything from text input and game control to doodling.
"Touch panels are deemed as a critical platform for the future of human–computer interaction and [the] metaverse," the researchers explain by way of background to their work. "Recently, stretchable iontronic touch panels have attracted attention due to their superior adhesivity to the human body. However, such adhesion can not be named 'real wearable,' leading to discomfort for the wearer, such as rashes or itching with long-time wearing."
Nobody wants rashes form their wearable, regardless of how useful it may be, which is the problem the team set out to solve — creating a "real wearable" version of an iontronic interface that combines a hydrogel with knit silk fabric layers. In doing so, the user is insulated from the hydrogel — meaning it doesn't stick — while the mechanical performance of the resulting touch device is dramatically improved, by three orders of magnitude according to the team's testing.
To prove the concept, the researchers built a prototype wearable in the form of a fabric armband and put it to work in a range of tasks: serving as a keyboard for text input; controlling a Tetris-style falling block game; and, combined with a stylus for better precision, drawing a range of shapes including a heart, a hand, the Olympic rings, a panda, and SpongeBob SquarePants.
Key advantages of the team's armband over rival designs, in addition to its comfort for long-term use, include its ability to operate accurately even when stretched or deformed and its insensitivity to stable pressure from external sources — ranging from a lightweight silver fiber, which may be used alongside the pad in fabric-based wearable electronics projects, to a 10kg (22lb) metal block.
The team's work has been published under closed-access terms in the journal ACS Nano; no roadmap has been given for potential commercialization.