What is Array of Things?

The Array of Things (AoT) is an urban sensing project, a network of interactive, modular sensor boxes that will be installed around Chicago to collect real-time data on the city’s environment, infrastructure, and activity for research and public use. AoT will essentially serve as a “fitness tracker” for the city, measuring factors that impact livability in Chicago such as climate, air quality and noise.

What are the goals of Array of Things?

Array of Things is an urban-scale “instrument” that will enable the City, urban planners, residents, and researchers to monitor and examine Chicago’s environment, infrastructure and activity, including detecting trends and changes over time. Ultimately, the goal is to measure the city in sufficient detail to provide data to help engineers, scientists, policymakers and residents work together to make Chicago and other cities healthier, more livable and more efficient.

How will AoT benefit Chicago?

AoT will provide real-time, location-based data about the city’s environment, infrastructure and activity to researchers and the public. This initiative has the potential to allow researchers, policymakers, developers and residents to work together and take specific actions that will make Chicago and other cities healthier, more efficient and more livable. The data will help make Chicago a truly “smart city,” allowing the City to operate more efficiency and realize cost savings by anticipating and proactively addressing potential problems like urban flooding.

Because the data will be published openly and without charge, it will also support the development of innovative applications, such as a mobile application that allows a resident to track their exposure to certain air contaminants, or to navigate through the city based on avoiding urban heat islands, poor air quality, or excessive noise and congestion.

What data will be collected by AoT?

The nodes will initially measure temperature, barometric pressure, light, vibration, carbon monoxide, nitrogen dioxide, sulfur dioxide, ozone, ambient sound intensity, pedestrian and vehicle traffic, and surface temperature. Continued research and development will help create sensors to monitor other urban factors of interest such as flooding and standing water, precipitation, wind, and pollutants.

Who will have access to the AoT data?

Data collected by AoT will be open, free, and available to the public. The nodes will transmit data to a secure central database server at Argonne National Laboratory. Data will then be published openly to allow individuals, organizations, researchers, engineers and scientists to study urban environments, develop new data analysis tools and applications, and inform urban planning. Raw data will also be posted to the City of Chicago’s open data network and Plenario, a web-based portal that supports open data search, exploration, and download with open datasets from Chicago and around the world.

What can be done with this data?

Potential applications of data collected by the Array of Things include:

But importantly, the team expects that many unanticipated, innovative applications will be constructed by outside parties using the open Array of Things data, realizing the potential of an open, community-based initiative.

When and where will nodes be installed?

In partnership with the City of Chicago, a total of 500 nodes will be mounted on streetlight traffic signal poles around the city over the next two to three years. The first prototype nodes were installed in summer 2016, and more will be installed throughout 2017 and 2018. The Array of Things team will work with several partners, including the City of Chicago’s Department of Information and Technology and Department of Transportation, researchers, neighborhood groups and community members, to determine the best locations for the deployment of AoT. View a map of the proposed locations for the first 42 nodes

How will privacy and security be protected?

All hardware, software and data being collected will be regularly reviewed by a Technical Security and Privacy Group chaired by Von Welch, director of Indiana University’s Center for Applied Cybersecurity Research. Operating as an external, independent review team, the committee will also be consulted whenever there is a request for a new kind of data to be collected.

The Array of Things Executive Oversight Council will be co-chaired by the Commissioner of the City's Department of Innovation and Technology and the Urban Center for Computation & Data Director, with additional members selected from academia, industry, non-profits, and the community. No data will be monitored without the approval of the privacy and security external oversight committee, the City of Chicago and the AoT executive committee, and the operation of the Array of Things will be governed by privacy policies that will be published prior to installation of nodes.

Will the nodes collect information about people?

Array of Things is interested in monitoring the city’s environment and activity, not individuals. In fact, the technology and policy have been designed to specifically avoid any potential collection of data about individuals, so privacy protection is built into the design of the sensors and into the operating policies.

To this end, each sensor that has a potential impact on privacy is operated with specific safeguards in place. The sound sensor will only collect data on ambient volume (the level of noise at the node) and will neither record nor transmit the raw microphone data. A low-resolution infrared camera will be included in each node, pointed at the road surface and sidewalk, with the sole purpose of measuring surface temperature. An imaging camera will be included in each node to detect features such as standing water, weather conditions, and sky color (an indicator of pollution), or to count the number of pedestrians and various types of vehicles on public streets. All images will be processed into numerical data within the node, after which image data will be immediately deleted. After initial calibration, no images or video will be stored within or transmitted from the nodes.

I heard that sensors will be installed to monitor Bluetooth-enabled devices and WiFi signals. Is this true?

No, none of the AoT sensors will measure the presence of Bluetooth/WiFi devices or communicate in any way with devices—the nodes are programmed to communicate only with the central database at Argonne. Previously, the project considered including such sensors in the nodes, but we decided against it for two reasons: we realized it would be biased toward people who own connected devices and thus would not provide the most accurate indicator of foot traffic, and the public expressed concerns about their devices being contacted or detected in any way.

What other cities will be using AoT nodes?

The project has received over 100 requests from cities and universities to partner with the Array of Things team. We are currently in various stages to commission 8-12 pilot projects in other cities over the next few quarters. Examples of pilot locations include Detroit, Denver, Seattle, Portland, Syracuse, and Chapel Hill, as well as several international cities. Each pilot city or university will receive three to ten nodes for use in monitoring local environmental, infrastructure and activity data.

I had heard AoT was planning to install the first nodes last year. Why was the project delayed?

Our initial installation projections were ambitious. As we did additional research and preparation for the installation, we realized a lengthier process was needed to further test and refine the technology to ensure the sensors and nodes would measure and transmit data effectively and that the devices would be highly resilient to harsh weather conditions. That extra time allowed us to not only fine-tune the devices and develop a more efficient production process, but the technology also improved over the past year to produce more reliable measurements and a cost savings of nearly 50 percent for the project. A pilot project underway on the University of Chicago campus has also helped us test and calibrate the node technologies.

Who is the Array of Things team?

The Array of Things project is led by Charlie Catlett and researchers from the Urban Center for Computation and Data of the Computation Institute, a joint initiative of Argonne National Laboratory and the University of Chicago. The underlying software and hardware design, known as Waggle, was developed at Argonne National Laboratory by Pete Beckman and Rajesh Sankaran. The custom enclosure for the sensor nodes was developed by Product Development Technologies, based on early designs from Douglas Pancoast and Satya Mark Basu of the School of the Art Institute of Chicago. The project is executed in partnership with the City of Chicago.

The Array of Things project also involves partnerships with scientists at academic institutions including Northern Illinois University, University of Illinois at Chicago, University of Illinois at Urbana-Champaign, DePaul University, Illinois Institute of Technology, Purdue University, University of Notre Dame, Arizona State University, the Santa Fe Institute, University College London, Clemson University, and the Institute for Advanced Architecture of Catalonia. Technical advice and support comes from a growing number of industry partners including Cisco, Microsoft, Schneider Electric, Intel, Motorola Solutions, and Zebra Technologies.

Who is funding AoT?

The University of Chicago received a $3.1 million grant from the National Science Foundation for the AoT project. The project has also received investments of $150,000 each from the Chicago Innovation Exchange and Argonne National Laboratory to fund the pilot project. The underlying platform technology is the result of over $1 million of internal research funding from Argonne National Laboratory. Additionally, the City of Chicago will fund the installation of nodes and provide electricity to them from the City’s power supply via the traffic signal poles to which nodes will be attached.

How much does an AoT node cost?

AoT nodes are experimental, and we expect that some nodes may have expanded capabilities, such as anemometers (to measure wind speed), precise air particle sensors (to measure pollutants like smoke or pollen), and sky-facing imagers to understand cloud cover and sunlight. The cost will vary based on the exact selectin of sensors and other components.

How much will this project cost the City of Chicago?

The City of Chicago will fund the installation of nodes and provide electricity to them from the City’s power supply via the traffic signal poles to which nodes will be attached. The City is providing an extremely small amount of electricity to the nodes on City street lights (less than needed to charge a cell phone) and DoIT and CDOT are providing support services as described above.