Data sensor
1. The plastic casing was built using 3D printing so it can be switched out easily. 2. Hexagonal cutouts frame the LED lights to differentiate the nodes from streetlights or cameras. Future nodes may be screenprinted with diagrams or logos (the Chicago flag’s stars, for example). 3. The “sensor rail” gathers basic environmental data and sends readings to the team at the Urban Center for Computation and Data at the University of Chicago. The team will then post findings to the city’s data portal. Photo: Courtesy of the Computation Institute

If you walk through Hyde Park this month, you’ll notice some odd-shaped cylinders strapped to streetlamps. No, they’re not the latest city cameras out to catch you running (maybe) a red light; they are new data trackers that may soon be rolling out across Chicago.

The project is called the Array of Things, and it comes from the Computation Institute, a collaboration between the University of Chicago and Argonne Labs. Twenty nodes scattered around the U. of C. will monitor temperature, humidity, light, sound, carbon monoxide, nitrogen dioxide, and motion. The senior fellow leading the project, Charlie Catlett, describes them as Fitbits for the city—tracking Chicago’s health.

The project is great news for data geeks, but it has the potential to help everyday Chicagoans, too. Eventually, for instance, the nodes’ infrared surface-temperature sensors could alert drivers and pedestrians that roads and sidewalks are icy. Weather data could be available block by block. And by analyzing foot traffic, the nodes could warn walkers of empty streets at night.

How, exactly? The team built in a Bluetooth modem that pings nearby cell phones, a worry for open-data skeptics but one that Catlett is not concerned about. “We’re just pinging the devices,” not peering inside, he says. “Then we’re throwing the addresses away and counting the number of responses we got.”

The team hopes to expand the project to the Loop next year, but first the nodes have to pass a big test: survive a Chicago winter.