Published on May 6th, 2017 | 5,130 views
The Security System That Sees Through Walls
Some require sensors on every door and window, or motion detectors in every room. Lots of DIY security systems rely on streaming cameras, which can have the creepy side effect of turning your family life into a reality show.
So what if I told you we now have the technology to “see” through walls, around corners and through your house—without cameras? It’s possible because researchers figured out how to measure disruptions in the invisible radio waves all around us. They put eyes on your Wi-Fi.
This sounds like a hallucination, but it’s real and it works. I’ve been testing the first consumer radio-wave sensing device, the $500 Aura, in a few different locations. It’s pricey and can’t cover all homes or security situations, yet it holds a lot of promise as a simpler, less-invasive way to buy a little peace of mind.
Aura isn’t a home security system like ADT, installed and monitored by professionals for a monthly fee. Plenty of folks swear by those traditional systems, but smart-home tech is making it more feasible than ever to take a do-it-yourself approach to security that’s not only potentially cheaper, but also friendlier to a world centered on smartphones.
Radio waves fill our homes, whether we like to think about that or not. These are like ripples in a pond, flowing through walls and bouncing around in pretty regular patterns, until something—or someone—gets in the way. By scanning those waves, Aura is literally looking for…disturbances in the Force. (Sorry, couldn’t help myself.)
That’s why I tested it by trying to break into my own house. Moments after I climbed through the back window, Aura’s sensors caught me. In the app, I could see my movement plain as day, in a waveform like a seismograph reading of an earthquake. When I stopped moving, the waveform flatlined. When I crept along slowly, on all fours, it even registered that, too.
This tech, developed over years in the lab, beats old-school motion sensors because a single pair of Aura sensors can spot movement through large swaths of a multistory home. And its maker, Waterloo, Ontario-based Cognitive Systems Corp., figured out which radio disruptions might indicate an intruder, rather than a spinning fan, a puttering pet or a leaf falling off the plant you forgot to water.
It’s complicated science, but pretty simple to set up. In one corner of the house you plug in a hub the size of a tissue box. And in another corner, you plug in candybar-sized sensor. Aura then constantly measures a field the shape of a football in between them. Placement is extremely important: Homes can have funny shapes, and obviously Aura can’t pick up motion that’s not between the nodes.
You can arm it manually with your phone, like a regular system. Or you can tell Aura to watch for the comings and goings of smartphone-carrying family members, automatically arming when nobody’s home.
When it’s armed and detects motion, Aura can set off an alarm, alert your phone or—using a free service called If This Then That—trigger something else to happen in a smart home, like switching on lights or a security camera.
The size of homes, their layouts and often the materials they’re made out of can all affect Aura’s reach. In my open-plan office, I could get decent Aura coverage with 40 feet between the nodes. In my 1910s-era San Francisco condo, old walls with plaster built around chicken wire blocked Aura considerably, so I could only fully cover a central hallway. Aura’s maker says it is working on additional sensors to expand its range.
My colleague had fewer problems in a 1920s-era single family home in New Jersey, which had a mixture of building materials, and where Aura covered about 60% of the house. I had been worried the sensors might pick up activity from any neighbors or people out in the street, but that never happened in our tests.
Aura behaves like other home DIY security systems. For instance, it continues on battery power if the power is cut, detecting motion and setting off an alarm (though it can’t send updates to your phone without internet access). If you set up automatic arm/disarm, it can send a notification when people come home and when they leave.
But there are some holes in Aura’s current functionality that should give initial buyers pause: Aura can’t connect to other security systems or call the cops for you if someone has really broken in. It can’t warn you about break-ins that might occur while you’re home, and possibly sleeping. There’s no way yet to adjust its sensitivity to weed out alerts about movements from more active pets. And unlike those pesky cameras, it won’t produce photographic evidence for the cops.
And like many new technologies, Aura also raises some new concerns about privacy. It’s an invisible tracking tech that could technically be used to snoop or surveil without its target knowing. Over time, could software upgrades even allow it to keep track of particular people or types of activity?
Could bad guys burgle or stalk you using Aura data? Cognitive Systems says its CEO developed the encryption code for BlackBerry ,and its tech uses a cryptographic chip. The company says it doesn’t ever look at your private activity, which it keeps separate from any identifiable customer data. Aura says it holds on to the data for seven days.
There are cheaper or more comprehensive ways to secure a home. But my guess is, we’ll see this kind of tech built into Wi-Fi routers, which could then bill themselves as security systems, too. The walls really can finally talk—and that’s a part of our future for better and for worse.