Your Smartphones and Smartwatches Could Use Sound to Detect Motion

Researchers at the University of Berkeley are experimenting with a different kind of user interface that relies on ultrasound technology – something that’s typically used for medicine and submarines. Named after its sound wave sonar technology, the Chirp interface would free our hands and fingers from constantly touching our screens while using very low energy and requiring hardly any light for accuracy.

Chirp measures gestures much like sonar navigation. The tiny chip sends out ultrasonic waves using an array of ultrasound transducers that sends back echoes when it detects motions and objects.  The simple device is so efficient, its miniature battery can last for up to 30 hours. With a chip as small as 1-2mm, the it’s perfect for small applications like smart watches  with screens too petite for fingers.

ultrasound chip

How sonar works