The curled metal fixtures set to go up on a handful of Michigan Avenue light poles later this summer may look like delicate pieces of sculpture, but researchers say they'll provide a big step forward in the way Chicago understands itself.

The curled metal fixtures set to go up on a handful of Michigan Avenue light poles later this summer may look like delicate pieces of sculpture, but researchers say they'll provide a big step forward in the way Chicago understands itself by observing the city's people and surroundings.

The smooth, perforated sheaths of metal are decorative, but their job is to protect and conceal a system of data-collection sensors that will measure air quality, light intensity, sound volume, heat, precipitation and wind. The sensors will also count people by measuring wireless signals on mobile devices.

Some experts caution that efforts like the one launching here to collect data from people and their surroundings pose concerns of a Big Brother intrusion into personal privacy.

In particular, sensors collecting cellphone data make privacy proponents nervous. But computer scientist Charlie Catlett said the planners have taken precautions to design their sensors to observe mobile devices and count contact with the signal rather than record the digital address of each device.

Researchers have dubbed their effort the "Array of Things" project. Gathering and publishing such a broad swath of data will give scientists the tools to make Chicago a safer, more efficient and cleaner place to live, said Catlett, director of the Urban Center for Computation and Data, part of a joint initiative between the University of Chicago and Argonne National Laboratory, near Lemont.

The novelty of a permanent data collection infrastructure may also give Chicago a competitive advantage in attracting technological research, researchers contend.

"The city is interested in making Chicago a place where innovation happens," said Catlett.

Many cities around the globe have tried in recent years to collect enormous piles of "big data" in order to better understand their people and surroundings, but scientists say Chicago's project to create a permanent data collection infrastructure is unusual.

Data-hungry researchers are unabashedly enthusiastic about the project, but some experts said that the system's flexibility and planned partnerships with industry beg to be closely monitored. Questions include whether the sensors are gathering too much personal information about people who may be passing by without giving a second thought to the amount of data that their movements — and the signals from their smartphones — may be giving off.

The first sensor could be in place by mid-July. Researchers hope to start with sensors at eight Michigan Avenue intersections, followed by dozens more around the Loop by year's end and hundreds more across the city in years to come as the project expands into neighborhoods, Catlett said.

"Our intention is to understand cities better," Catlett said. "Part of the goal is to make these things essentially a public utility."

Over the last decade many cities have launched efforts to collect data about everything from air quality and temperature at street level to the traffic flow of pedestrians and vehicles, all in the name of making urban centers run more efficiently and safely.

Much of the useful data has been "exhaust" from an increasingly digital and technological world, scientists say. Improvements in such technologies have led to novel conveniences like smartphone applications that tell you whether your bus is on time or how backed up the expressway is likely to be when you head home.

But Chicago researchers are hoping to put in place a system that will make this city a leader in research about how modern cities function, Catlett said.

The decision to move forward with the system has unfolded without much attention outside the technology community. Mayor Rahm Emanuel, who rarely misses a chance to push Chicago as an emerging digital hub, has yet to tout the project publicly.

City officials don't have firm expectations about what the data may yield but share researchers' desire to push "Chicago as a test bed of urban analytical research," said Brenna Berman, the city's commissioner of information and technology. "Part of why this is so exciting is a lot of the analytics we do is targeted to a specific problem, and this is more general."

Berman said the investment from the city will be minimal: Between $215 and $425 in city electrician wages to install each box and then an estimated $15 a year for electricity to power each box.

Berman's office had a say in picking the initial sensor lineup, and she said the list was limited to "nonpersonal" data because the city is still working on a privacy and security policy to govern the protection and confidentiality of any data that the system may collect in the future. Berman expects she and Emanuel will agree on a final version of the document by the end of July.

"We've been extremely sensitive to the security and the privacy of residents' data," Berman said.