Scientists have created a computing ring that could be used to make phone calls, send voicemails or answer text messages - all without the wearer reaching for their phone or even looking at it.
The system called Fingersound is triggered by a thumb ring outfitted with a gyroscope and tiny microphone. It allows people to trace letters on their fingers and see the figures appear on a nearby computer screen.
As wearers strum their thumb across the fingers, the hardware detects the movement, said researchers from Georgia Institute of Technology in the US.
While other gesture-based systems require the user to perform gestures in the air, Fingersound uses the fingers as a canvas.
This allows the system to clearly recognise the beginning and end of an intended gesture by using the microphone and gyroscope to detect the signal.
In addition to helping recognise the start and end of a gesture, it also provides tactile feedback while performing the gestures. This feedback is crucial for user experience and is missing on other in-air gestures.
"Our system uses sound and movement to identify intended gestures, which improves the accuracy compared to a system just looking for movements," said Cheng Zhang, from the Georgia Institute of Technology.
"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."
Fingersound sends the sound captured by the contact microphone and motion data captured by the gyroscope sensor through multiple filtering mechanisms.
The system then analyses it to determine whether a gesture was performed or whether it was simply noise from other finger-related activity.