The researchers built a small sensor that can be placed on an electronic device such as a smartphone. The sensor uses an ultra-low-power receiver to extract and classify gesture information from wireless transmissions around us. When a person gestures with the hand, it changes the amplitude of the wireless signals in the air. The AllSee sensors then recognize unique amplitude changes created by specific gestures.
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The low-power chip makes it possible to interact with mobile devices and a host of other consumer electronics using hand gesture recognition, which today is usually accomplished with camera-based sensors. A key limitation is that it only recognizes motions, such as a hand flick or circular movement, within a six-inch range.
The controller comes with the ability to recognize 10 predefined gestures, including wake-up on approach, position tracking, and various hand flicks, but it can also be programmed to respond to custom movements. Similar to the programming of voice recognition software, Microchip Technology built the gesture library using algorithms that learned from how different people make the same movements. These gestures can then be translated to functions on a device, such as on/off, open application, point, click, zoom, or scroll.