SkinTrack transforms forearm into a smartwatch touchpad
Researchers at Carnegie Mellon University are working on a project called SkinTrack, that could see the human arm used in the same way as a touchscreen. By combining a ring that gives off an electrical signal, picked up by a electrode-laden smart watch, scientists say instead of trying to work their way round a tiny touchscreen, users can swipe up and down their forearm, playing games, navigate maps or make calls, all in real-time. Gierad Laput, a graduate student at the university and one of the researchers behind SkinTrack, said modifications would be needed to the existing prototype, and thought it would be a “few years” before it was good enough to use.

SkinTrack, a research project from Carnegie Mellon University, lets you use your arm as a touch pad for a smart watch.

Wearable gadgets like smart watches can be hard to interact with because they tend to have tiny displays. So the researchers figured that using your skin—specifically your wrist and hand—as a touch pad could make it easier to do things like navigate maps, make calls, or play games.

Gierad Laput, a graduate student at Carnegie Mellon University and one of the researchers behind the project, says SkinTrack works similarly to how cell towers triangulate signals to figure out your phone’s location. The researchers got SkinTrack to determine when the finger was on the skin 99 percent of the time. And by arranging the electrodes in the smart watch in a certain way, they could determine in real time where the finger was, tracking its movements on the arm and hand.

SkinTrack can sense where your finger is on your skin and track it in real time.

With SkinTrack, your arm could be used as a touch pad for all kinds of gestures, like dialing a virtual keypad.

To try out SkinTrack, the researchers made several demos, including one of an Angry Birds game that could be played on their smart watch. You swipe your finger up your arm to pull the bird back in a slingshot on the watch’s display. “And when you release, the app can know the finger is off the skin, so that’s like releasing the slingshot,” he says.

As a video of the project shows, it can also be used for all kinds of gestures—like swiping left, right, up, or down. It could also be used for making the skin a virtual number pad or other kind of button pad, Laput says, or opening an app by tapping a specific spot or gesturing a letter on your arm (writing an “M” with your finger might prompt music to start playing, for instance).