SkinTrack will turn your lower arm into a vast touch pad

Smart watches never really made it to the revolutionary gadget list given its two opposing facets- a bulky body and a way too small screen interface. There isn’t much you can do with that small screen. But seems like, we have a solution now. Researchers at the Future Interfaces Group (FIG), an organization within the Human-Computer Interaction Institute at Carnegie Mellon University say that we can expand interactions beyond the confines of the small watch face and turn the entire lower arm into a touchpad.
Named SkinTrack, the wearable technolgy involves a ring that emits a high-frequency signal and a wristband packed with electrodes. As the ring’s signal propagates through the body, SkinTrack measures the phase difference between electrodes on either end of the band to figure out the location of fingers on the skin. This in turn transforms the wearer’s wrist into a 2D trackpad for a smartwatch screen.
The researchers found that they could determine when the finger was touching the skin with 99 percent accuracy and they could resolve the location of the touches with a mean error of 7.6 millimeters. That compares well with other on-body finger-tracking systems and approaches touchscreen-like accuracy.

"The great thing about SkinTrack is that it's not obtrusive; watches and rings are items that people already wear every day," says Yang Zhang, a first-year Ph.D. student in HCII. He will present details of the technology May 10, 2016 at CHI 2016, the Association for Computing Machinery's Conference on Human Factors in Computing, in San Jose, California.

In a demo on YouTube, the wearer is able to scroll through music tracks, tap on their hand’s invisible phone dialer, draw letters, and even play a game of Angry Birds. The researchers note that the system works with clothing over the wrist, and can even pick up movements just above the skin.

"A major problem with smartwatches and other digital jewelry is that their screens are so tiny," says Gierad Laput, another Ph.D. student in HCII and part of the research team. "Not only is the interaction area small, but your finger actually blocks much of the screen when you're using it. Input tends to be pretty basic, confined to a few buttons or some directional swipes."

Through SkinTrack, interactions move beyond the screen onto the arm, providing much larger interface. Importantly the technology is safe. No evidence suggests that the radio frequency signals used by SkinTrack have any health effects. The body is commonly excited by daily appliances—everything from the tiny amounts of current drawn from the finger by touchscreens to the electromagnetic noise emanating from fluorescent lights—with no ill effects.

However, there’s one problem: The current prototype is pretty bulky, requiring hefty electronics on the ring and a wide wristband that has its own circuit board. But the researchers don’t see this as a long-term problem: “As our approach is compact, non-invasive, low-cost, and low-powered, we envision the technology being integrated into future smartwatches, supporting rich touch interactions beyond the confines of the small touchscreen,” they wrote on YouTube.