By Rob Mitchum // July 13, 2015
Imagine you are an asthma sufferer who works in a downtown Chicago office building. One morning, the weatherman warns of a high pollen count, but with no details beyond the city’s overall pollen level that day. So you open up an app on your phone that shows you a real-time map of the pollen count on each city block, and even plots the route with the cleanest air from the train station to the office. Along your walk, artful boxes mounted on streetlights change color as new data updates the local pollen levels, further guiding your path.
That is just one potential application of the data that will be collected and released by the Array of Things, a new urban sensing project developed by scientists from the University of Chicago, Argonne National Laboratory, and the Computation Institute, in partnership with the City of Chicago and the School of the Art Institute of Chicago. Open data collected by interactive sensor “nodes” will serve as a “fitness tracker” for the city, providing valuable new information for residents, scientists, and policymakers to build a safer, cleaner, and more efficient urban environment.
The first two nodes were activated this week at the Reva and David Logan Center for the Arts and Regenstein Library at UChicago, part of a pilot phase that will bring 10 to 12 nodes to the campus. Eventually, the Array of Things team hopes to mount hundreds of nodes throughout Chicago neighborhoods. Each one will contain sensors for temperature, humidity, light, sound levels, air quality and more, to take the pulse of the city at unparalleled resolution. All data will be available to the public, for use in research studies, application development, or civic improvement, stimulating the local tech industry and community engagement with the city.
“The Array of Things will create a new public utility of open data for the citizens of Chicago,” said Charlie Catlett, director of the Computation Institute’s Urban Center for Computation and Data and senior computer scientist at Argonne. “The unprecedented flow of data from these sensors will create exciting new opportunities for research, technology development, and education that will enrich our knowledge about the city.”
Data For A Better City
To get a city into better shape, you want to start with the best possible information. For instance, how healthy is the air that its residents breathe? What are the bottlenecks for vehicle and pedestrian traffic? Where are the pockets of unusual weather patterns that may require more attention from city services?
While cities today release more data for public use, many of these questions are beyond the scope of what governments currently measure and collect. The Array of Things will gather rich additional data to address such questions, with several kinds of measurements taken often and at numerous locations. By making the sensor output free and open, the project hopes to supply Chicago’s thriving tech and programming communities with the raw material to build valuable, useful new tools for city residents.
After early discussions with the City of Chicago Department of Innovation and Technology, the Array of Things was included as a “next-generation infrastructure” in Mayor Rahm Emanuel’s Chicago Tech Plan, released in late 2013. As the project expands beyond campus, the City will manage the installation of the nodes on streetlights and lead an executive committee that grants final approval for all instrumentation and data collection.
“The Array of Things is a system that collects data about Chicago at the micro level to drive a deeper understanding of how the city works and how it can be improved to meet the needs of its residents today and in the future,” said Brenna Berman, Chief Information Officer for the City of Chicago.
Array of Things data will also provide a resource for researchers from many scientific disciplines. Hyper-local weather data will give climate researchers the ability to study micro-climates and heat pockets within the city. Public health experts can combine data on air quality, humidity, excessive noise, and other measures with medical statistics to look for possible environmental contributors to disease. Social scientists may use data on noise level, weather, or foot traffic to see how these urban factors affect crime or livability in different neighborhoods.
“The meteorological sensors included in an Array of Things node will help us understand phenomena such as the urban heat island,” said Robert Jacob, computational climate scientist at Argonne and Computation Institute senior fellow. “The dense coverage and 24/7 uptime will provide an entirely new way of looking at the urban atmosphere.”
The creation of a citywide network of modular sensor nodes should also spur economic development in Chicago, as companies seeking a platform for testing new technologies on this unique platform bring their business to the area. Already, early partnerships with Cisco, Microsoft, Intel, Motorola Solutions, Schneider Electric, Zebra Technologies, Qualcomm, and others have brought industry input and expertise to the design of the pilot nodes.
“Throughout the Array of Things design process we have interacted with a broad range of scientists, policymakers, and citizens, each with questions about the city that cannot be answered with today’s data,” Catlett said. “The dynamics of cities that unfold on a neighborhood level, whether related to asthma and air quality or noise and traffic patterns, cannot be understood by studying daily air quality measurements for the entire South Side, or noise measurements in a dozen locations across a 588-square-kilometers city like Chicago.”
What’s Inside the Node?
On the outside, each node is a smoothly contoured, hard plastic shell, not much bigger than a cereal box, with a webbed, laser-cut design on the face. But inside is a densely-packed assembly of sensors and computer hardware, designed to withstand the harsh extremes of Chicago weather. Based on the Waggle sensor platform, developed by Argonne scientists Catlett, Pete Beckman, and Rajesh Sankaran, Array of Things nodes will draw power from the city streetlights where they will be mounted and will upload data as often as twice per minute, 24 hours a day, 365 days a year.
Unlike sensor boxes used in other cities, Array of Things nodes will be modular so that researchers can swap different kinds of sensors in and out of the enclosure as technologies improve and research questions evolve. Initially, Array of Things nodes will contain sensors measuring temperature, humidity, barometric pressure, light, vibration, carbon monoxide (CO), nitrogen dioxide (NO2), sulfur dioxide (SO2), ozone (O3), vibration, and ambient sound intensity.
Subsequent phases will incorporate more expensive technology needed for detecting precipitation, wind, and pollutants such as carbon dioxide and volatile organic compounds. Future nodes may also use a wireless network to estimate nearby pedestrian traffic by counting the number of WiFi- or Bluetooth-enabled devices in range. No personal data will ever be collected by this method or any other sensor installed in Array of Things nodes.
But the innovation behind Array of Things goes beyond the sensors and computational technology. In designing the node enclosures, lead designers Douglas Pancoast and Satya Mark Basu, of the School of the Art Institute of Chicago, explored a variety of node enclosure designs that can be customized for installation sites in various parts of the city. Their mission was to create attractive, eye-catching structures that fit into the Chicago urban landscape, so that community members perceive and understand the Array of Things as a valuable new urban infrastructure.
The UChicago pilot installation will test the materials and the design, so that for future expansions, the designers can collaborate with community members to create unique designs and functions that represent the neighborhoods where nodes are mounted. Newer generations of the nodes may also include interactive features, such as LED lighting for directly visualizing and communicating data to passersby.
“The University of Chicago pilot is a great way to carefully initiate the Array of Things project,” Pancoast said. “For the full network to work, it really needs to grow from the ground up, where each installation provides some learning opportunity on neighborhood fit and value that can be applied to future installations. We have the opportunity to begin that here.”
Last summer, a group of high school students from Chicago’s Woodlawn neighborhood gathered on the UChicago campus to learn firsthand what sensor technology could tell them about their surroundings. Students took home early versions of Array of Things sensors for temperature, humidity, and air quality, and placed them in locations of their own choosing: a garden, a city street, inside their home. A week later, they brought the devices back and visualized the data with Array of Things researchers, discovering some surprising results, such as buildings where the air quality inside is worse than outside.
This workshop offered a glimpse at a key component of the Array of Things project as it grows: collaboration with the community. Before nodes are installed in a neighborhood, researchers will meet with residents, students, and local leaders to brainstorm not just the design of the nodes, but the types of questions researchers and community members will address and the sensors needed for those questions. One community may want to prioritize air pollution research due to concerns about a nearby power plant. Another may prefer to measure foot traffic, to provide useful data on how local businesses should set their hours.
The Array of Things team will also hold frequent “hackathons” for experienced programmers, curious residents, and students of all ages to dive into the data and collaborate on new applications and ideas.
“We believe this network will help build communities and encourage civic participation by making very resolute data on city environments available and accessible to all,” said Pancoast, associate professor in the Department of Architecture, Interior Architecture, and Designed Objects at SAIC. “The Array of Things is primarily a platform and instrument for urban science, but it is also a form of community technology.”
For more information about Array of Things, visit arrayofthings.us, or contact the project team at firstname.lastname@example.org.