Wave Hello! Handheld X-Ray Device Tracks Movement Through Walls

By Nick Venable | Published

This article is more than 2 years old

x-rayWhen a conversation about X-ray vision comes up, it’s usually in the context of which of Superman’s powers I would get arrested while using. But it won’t always exist purely in the realms of comic book fiction. (Or on the back pages of comic books, next to snap gum and sea monkeys.)

Dina Katabi, a professor at MIT’s Department of Electrical Engineering and Computer Science, worked with her graduate student Fadel Adib to create a low-cost handheld device that can track an object or human’s movement through a wall. They call their system Wi-Vi, and technically, they won’t be using X-rays at all, but WiFi signals. (Which is why it isn’t called X-Vex, I guess.)

Based on concepts similar to sonar and radar imaging tactics, the Wi-Vi uses two transmitting antennas to send out a signal that is the inverse of the other, so that they cancel each other out, along with any non-moving items behind the wall they’re being pointed at, as well as the wall itself. But if something behind the wall is moving, the signals recognize this, and they can then be used to track whatever is back there. The MIT website story uses the word “human” a lot, but I’m already picturing this technology being used in a found-footage horror movie like [REC].

Attempts to create this same effect in the past have relied on large, bulky equipment and multiple receivers. The Wi-Vi fits in your hand and has just one receiver attached to it, and movement is tracked in relationship to that receiver. As you can see in the video below, a wavelength is used to identify how far away or close the movement is, and presently has the capability to track three different objects at once. So anyone hoping this technology would be extremely detailed or used for perverse purposes — definitely not me — might be disappointed by the low-tech output. Early stages, people!

This is quite different from the T-ray smartphone concept we’ve covered in the past, and I have to think that utilizing WiFi is the way to go, at least for this particular device.

“We wanted to create a device that is low-power, portable and simple enough for anyone to use, to give people the ability to see through walls and closed doors,” Katabi says. They foresee Wi-Vi being used as a personal safety device. “If you are walking at night and you have the feeling someone is following you,” Katabi adds, “then you could use it to check if there is someone behind the fence or behind a corner.”

Beyond that, they also foresee its use in search-and-rescue operations, checking to see if anyone is trapped or in danger. (Kind of like the Kinect-controlled cockroaches, just with 90% less heebie-jeebies.) Similarly, police officers could use it to assist them while entering unfamiliar areas, limiting the chance of an ambush.

For slightly less important purposes, the Wi-Vi could be implemented to give your home full gesture-operated technology, much like the recently developed WiSee system. It isn’t laziness, it’s the future! And it’s also only a matter of time before Microsoft Kinect jumps onto the WiFi bandwagon.

Don’t be surprised if hyper-superstitious grave robbers snatch up all of these as soon as they go on the market.

Subscribe for Science News
Get More Real But Weird

Science News

Expect a confirmation email if you Subscribe.