Conference Paper

3D Ultrasonic Gesture Recognition

DOI: 10.1109/ISSCC.2014.6757403 Conference: International Solid State Circuits Conference


Optical 3D imagers for gesture recognition suffer from large size and high power consumption. Their performance depends on ambient illumination and they generally cannot operate in sunlight. These factors have prevented widespread adoption of gesture interfaces in energy- and volume-limited environments such as tablets and smartphones. Wearable mobile devices, too small to incorporate a touchscreen more than a few fingers wide, would benefit from a small, low-power gestural interface. Gesture recognition using sound is an attractive alternative to overcome these difficulties due to the potential for chip-scale size, low power consumption, and ambient light insensitivity. Using pulse-echo time-of-flight, MEMS ultrasonic rangers work over distances of up to a meter and achieve sub-mm ranging accuracy [1,2]. Using a 2-dimensional array of transducers, objects can be localized in 3 dimensions.

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