Many gesture detection devices, including the Kinect and the Leap Motion, use infrared cameras to sense movement. They also have dedicated chips that process the data from the cameras. These components are power-hungry, especially if they’re turned on at all times. Researchers from the University of Washington have developed a gesture detection device that uses 1,000 to 10,000 times less power than its counterparts.
Bryce Kellogg, Vamsi Talla and their teacher Shyam Gollakota call the device AllSee. Instead of cameras and infrared light, it measures how the user’s hand affects ambient TV signals: “At a high level, we use the insight that motion at a location farther from the receiver results in smaller wireless signal changes than from a close-by location. This is because the reflections from a farther location experience higher attenuation and hence have lower energy at the receiver.”
The signal can also come from a dedicated RFID transmitter such as an RFID reader; future models may even use ambient Wi-Fi signals. The researchers even built prototypes that used TV signals both as source of data and as source of power, eliminating the need for a battery or plug.
Wave at your browser and go to the AllSee homepage for more on the device.