Researchers develop low-cost gesture recognition system
A team of computer scientists from the University of Washington has developed a low-cost gesture recognition system, called "AllSee," that runs without batteries and lets users control their electronic devices hidden from sight with simple hand movements. The technology uses existing TV signals as both a power source and the means for detecting a user's gesture command the researchers stated.
This development has put gesture control for electronics in the realm of possible alternatives to touchscreens and sensing technologies that use a lot of power and only work when users can see their smartphones and tablets.
"This is the first gesture recognition system that can be implemented for less than a dollar and doesn't require a battery," said Shyam Gollakota, a UW assistant professor of computer science and engineering. "You can leverage TV signals both as a source of power and as a source of gesture recognition."
The AllSee prototype is integrated with an off-the-shelf mobile phone. This technology enables new applications such as gesture recognition with the phone still in your pocket. Source: University of Washington.
The researchers built a small sensor that can be placed on an electronic device such as a smartphone was built that 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.
Sensors use three to four times less power than existing gesture recognition systems by harvesting power from wireless transmissions. This enables mobile devices to always have the gesture technology on and enabled.
AllSee detects the unique signal changes (shown on the oscilloscope) and classifies a rich set of hand gestures. Source: University of Washington.
Gesture recognition already is possible on some mobile devices, including the Samsung Galaxy S4 smartphone. But users have to first manually enable the feature and be able to see the device for the gesture technology to work, and if left on, the gesture system quickly drains the phone's battery. In contrast, AllSee consumes only tens of microwatts of power and can always be left on. The user could gesture at the phone in a pocket or handbag to change the volume or mute the phone without having to touch or see the phone.
This technology could also allow sensors to be attached to household electronics, making it possible to interact with everyday objects using gestures and also connect them to the Internet and to each other in an "Internet of Things" world.
"Beyond mobile devices, AllSee can enable interaction with Internet of Things devices. These sensing devices are increasingly smaller electronics that can't operate with usual keypads, so gesture-based systems are ideal," said Bryce Kellogg, a UW doctoral student in electrical engineering.
The UW team tested AllSee's capabilities on smartphones and battery-free sensors using eight different hand gestures such as pushing or pulling to zoom in and out. The prototype could correctly identify the gestures more than 90 percent of the time while performed more than two feet away from the device.
Researchers have tested the technology for response time and whether it can distinguish between other motions and those directed at it. They found that the technology's response time is less than 80ms, which is 1,000 times faster than blinking an eye.
"This enables a seamless and interactive experience for the user," said Vamsi Talla, a UW doctoral student in electrical engineering. The researchers also designed a wake-up gesture that allows the system not to confuse unintentional motions for actual gestures.
Beyond mobile devices, AllSee can also enable interaction with Internet of Things devices such as home monitoring solutions. Source: University of Washington.
This technology builds on previous work by Gollakota on leveraging Wi-Fi signals around us for gesture recognition around the home. Prior wireless gesture recognition techniques, however, consume tens of watts of power and aren't suitable for mobile or Internet of Things devices.
- Jean-Pierre Joosting
EE Times Europe