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The console camera of the future could track your movements through walls

MIT researchers have developed a camera that can build 3D models of users throughout a house - a potential game controller of the future.

A researcher using the WiTrack system. (Image: MIT)

The newest generation of consoles is going to get us used to being constantly watched by cameras in our living rooms. This might not be how Microsoft would put it, but that’s what the effect of an always-on Kinect will be. People have been penalised for swearing, at themselves, in their own living rooms:

To clarify, that’s a man getting an in-game penalty in NBA 2k14 because he swore outside of the game. Other games have been found to have similar features. Players can toggle the game’s listening-in on or off, but the important point here is that it’s incredibly creepy, and it’s the default, by choice of the developers. The console offers that function, so games will use it.

Let’s look forward, then, to what we might see in the generation after this one. We’re probably going to have cameras that track us through walls. Researchers at the MIT Computer Science and Artificial Intelligence Lab (CSAIL) have developed a system called “WiTrack” that uses radio waves to build 3D images of game players as they move throughout their home, even when they’re in other rooms.

It builds on an earlier system called “WiVi”, developed by some of the same researchers, that was a rough system for tracking people using the Wi-Fi on a typical smartphone. It works based on quite a simple, but clever, insight - the radio waves that a Wi-Fi device emits, like a smartphone or router, are deflected and reflected by objects they come across in just the same way that the radio waves used in radar systems do.

The resolution of Wi-Vi was pretty unimpressive - it could pretty much only tell you if something was moving closer towards you or further away - but it was an exciting idea. At the time, it was suggested that it could be used in hostage situations to figure out where people were inside buildings, or used by rescue teams to find those trapped beneath rubble in the aftermath of an earthquake.

WiTrack, conversely, uses its own radio waves instead of Wi-Fi, meaning it can build up full 3D models of its immediate environment. Here’s more info from MIT:

WiTrack operates by tracking specialized radio signals reflected off a person’s body to pinpoint location and movement. The system uses multiple antennas: one for transmitting signals and three for receiving. The system then builds a geometric model of the user’s location by transmitting signals between the antennas and using the reflections off a person’s body to estimate the distance between the antennas and the user. WiTrack is able to locate motion with significantly increased accuracy, as opposed to tracking devices that rely on wireless signals, according to Adib.

“Because of the limited bandwidth, you cannot get very high location accuracy using WiFi signals,” Adib says. “WiTrack transmits a very low-power radio signal, 100 times smaller than WiFi and 1,000 times smaller than what your cell phone can transmit. But the signal is structured in a particular way to measure the time from when the signal was transmitted until the reflections come back. WiTrack has a geometric model that maps reflection delays to the exact location of the person. The model can also eliminate reflections off walls and furniture to allow us to focus on tracking human motion.”

If that's not enough, there's a video that walks through how it works:

Gamers can look forward, in theory, to a future Kinect-like system with WiTrack capability that can track them throughout their homes. You could lead a squad of soldiers into your kitchen, make a sandwich, and head back to the action in the living room. Or, more usefully, it could be deployed in care homes to detect when elderly patients fall.

It is also, as a bit of technology that can literally see through walls, quite creepy. Imagine the privacy headache that could arise if everyone in a block of flats could see through into their neighbours’ homes, and imagine the paranoia that people would have that the NSA was keeping watch on them (especially considering that we now know that governments have infiltrated games like World of Warcraft).

It's still hard to see quite how this technology could be rolled out in a consumer setting, but give it time and there are probably hints of what's yet to come here.

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