FingerSound Number Illustrations. FingerSound uses wearable ring technology to detect numbers and letters drawn on fingers. Credit: Georgia Tech

New technology will allow users to write down numbers and letters on a computer screen without having to look at or touch the actual computer.

Researchers from the Georgia Institute of Technology have developed a new computing ring that allows a user to trace letters and numbers with their fingers and see the figures appear on a nearby computer screen.

A thumb ring outfitted with a gyroscope and small microphone triggers the system, which is being called Fingersound.

“A ring augments the fingers in a way that is fairly non-obstructive during daily activities,” Cheng Zhang, the Georgia Tech graduate student who created the technology, said in a statement. “A ring is also socially acceptable, unlike other wearable input devices.”

The new system allows users to clearly recognize the beginning and end of an intended gesture by using the microphone and gyroscope to detect the signal. The system also provides tactile feedback, while performing the gesture, which is important for the user experience.

“Our system uses sound and movement to identify intended gestures, which improves the accuracy compared to a system just looking for movements,” Zhang said. “For instance, to a gyroscope, random finger movements during walking may look very similar to the thumb gestures.

“But based on our investigation, the sounds caused by these daily activities are quite different from each other,” he added.

The system sends the sound captured by the contact microphone and motion data captured by the gyroscope sensor through multiple filtering mechanisms and then analyzes the sound to determine whether a specific gesture was performed or whether it was noise from inadvertent finger-related activity.

The researchers said that the technology could eventually be used to send phone calls to voicemail or answer text messages without the user reaching for their phone or even looking at it.

“When a person grabs their phone during a meeting, even if trying to silence it, the gesture can infringe on the conversation or be distracting,” Thad Starner, the Georgia Tech School of Interactive Computing professor leading the project, said in a statement. “But if they can simply send the call to voicemail, perhaps by writing an ‘x’ on their hand below the table, there isn’t an interruption.”

The research was presented earlier this year at Ubicomp and the ACM International Symposium on Wearable Computing along with two other papers that feature ring-based gesture technology. FingOrbits allows the wearer to control apps on a smartwatch or head-mounted display by rubbing their thumb on their hand. With SoundTrak, people can write words or 3-D doodles in the air by localizing the absolute position of the finger in 3-D space, then see the results simultaneously on a computer screen.