New technology will allow you to track smartwatches finger in the air using sound waves

Scientists, including those of Indian origin, have developed a new sonar technology that lets you interact with mobile devices by writing or making gestures on a table, a sheet of paper or even in the air.

An application, FingerIO tracking finger movements fine-grained turning smartphones or smartwatches on active sonar system using microphones and speakers own device.

Because sound waves travel through the web and do not require a line of sight, even users can interact with a phone in a front pocket or hidden under SmartWatch sleeve jersey.

Researchers at the University of Washington (UW) showed that FingerIO can accurately track finger movements of two dimensions within 8 mm, which is sufficiently precise to interact with mobile devices today.

"You can write very easily in a SmartWatch screen, so we wanted to transform a desk or any area around a device on an input surface," said lead author Rajalakshmi Nandakumar, a doctoral student at the University of Washington.

"I do not need an instrument of my fingers with any other sensor - just use your finger to write something on a table or other surface and the device can track with high resolution," Nandakumar said.

Using FingerIO, you could use the flick of a finger to turn up the volume, press a button or scroll through menus on a smartphone without touching it, or even write a search command or text in the air instead of typing in a small screen.

FingerIO converts a SmartWatch or smart phone in a sonar system using the device itself speaker to emit an inaudible sound wave.

That signal bounces off the finger, and the "echoes" are recorded by microphones of the device and is used to calculate the location of the finger in space.

Using sound waves to track finger movement offers several advantages over other technologies such as cameras and radar that require both hardware custom sensor and greater computing power, said Shyam assistant professor Gollakota.

"Acoustic signals are large - because sound waves travel much slower than radio waves used in radar, you do not need much bandwidth processing, so everything is simpler," Gollakota said.

The researchers created a prototype smartphone application FingerIO and personalized SmartWatch with two microphones, which are required to follow the movement of the finger in two dimensions.

The researchers asked the testers to draw shapes like stars, squiggles or figure 8s on a touch panel next to a smart phone or running FingerIO SmartWatch.

Then they compared the tracings of the touchpad to the forms created by tracking FingerIO.

The mean difference between the drawings and tracings FingerIO was 0.8 centimeters by 1.2 centimeters smartphone and for the SmartWatch.

"Given that the finger is already a centimeter thick, that's enough to accurately interact with devices," graduate student Vikram Iyer said.