Need to turn off a light in the other room? Just flick a wrist from wherever you are in the house.
Call it the 21st century version of the clap-on, clap-off.
Relying on minute changes in Wi-Fi signals rather than cameras, motion detectors or other sensors, a new technology developed by University of Washington researchers can power on lights, change TV channels or raise the stereo volume with a mere gesture.
The researchers say the gesture technology works in a similar way to those on an Xbox Kinect device or a Samsung Galaxy S4 smartphone, but their version is cheaper because it takes advantage of existing Wi-Fi routers that can be easily modified. Users also don't have to be in the same room as the router because Wi-Fi signals pass through walls.
"Our approach is to see the motion and try using it an interesting way," said Shwetak Patel, an assistant professor of computer science and electrical engineering. "The technology can detect very minute changes in people's movement patterns."
In a paper published online this week, Patel and his colleagues have dubbed the technology WiSee. An individual's movement changes the frequency of the Wi-Fi signal, a shift that's recorded by an antenna on the router. So far, they've tuned the device to recognize nine gestures, including pushing, pulling and punching, with 94% accuracy.
Different antennas could be tuned to different individuals in a household, with a special gesture acting as a password.
The challenges the researchers have to conquer now are improving their code to handle overlapping signals and to control multiple devices at once.
Patel said he could see the technology used in several environments, from gaming to subtle motion tracking. No invasive cameras or easily detectable sensors would be needed.
Researchers at the Massachusetts Institute of Technology have looked at a similar technology that they called Wi-Vi. Patel said the MIT project was simply to capture the motion information.
The gesture-control industry is a growing one. Wearable electronics, such as an arm band that tracks movements and sends the information over Wi-Fi, are already hitting the market.