Research News

World’s largest open-track traffic experiment being conducted in Nashville Nov. 14–18

The CIRCLES Consortium, consisting of Vanderbilt University and several other universities, in coordination with Nissan North America, Toyota, GM, and the Tennessee Department of Transportation, will test 100 AI-equipped vehicles in an effort to mitigate human-caused traffic jams.

The experiments are scheduled to occur along a four-mile stretch of I-24 starting on Monday, Nov. 14 through Friday, Nov. 18, 2022between the hours of 5 a.m. and 10:30 a.m., integrated into the normal flow of traffic.

The I-24 MOTION testbed, where the AI-equipped vehicles will travel in the normal flow of traffic, is the only automotive testing environment of its kind in the U.S. It is opening in fall 2022 and is equipped with 300 4K digital sensors that are mounted on poles spaced 600 feet apart. The system generates data on the 260,000,000 vehicle-miles of traffic that occurs annually within the testbed.

In this experiment, researchers from the CIRCLES Consortium will deploy up to 100 vehicles, comprised of Nissan Rogue, Toyota RAV4 and a Cadillac XT5, that each include an AI-equipped adaptive cruise control technology used in an earlier experiment.

In that test—conducted with 20 cars on a closed track—just one vehicle equipped with the AI system changed the driving behavior of the other 20 cars, alleviating the stop-and-go dynamic that often leads to traffic jams with no obvious cause. Because of the ripple effects that the AI-equipped cars had on other drivers, researchers measured a sizeable fuel savings compared with driving in typical traffic jams.

As researchers increase the scale of the testing and introduce real world driving conditions, they will investigate whether the improved traffic and fuel-economy outcomes measured in the smaller study continue to hold.

This research is supported by the National Science Foundation, as well as the U.S. Departments of Transportation and Energy. Support was also provided by Toyota North America and General Motors.

CIRCLES Researchers and Original Equipment Manufacturers

Alexandre Bayen, associate provost and Liao-Cho Professor, Department of Electrical Engineering & Computer Science, University of California, Berkeley

Maria Laura Delle Monache, assistant professor, Department of Civil and Environmental Engineering, University of California, Berkeley

Jonathan Lee, senior engineering manager and project manager, Institute of Transportation Studies, University of California, Berkeley

Benedetto Piccoli, Vice Chancellor for Research and Joseph and Loretta Lopez Chair Professor, Department of Mathematical Sciences, Rutgers University-Camden

Benjamin Seibold, professor, Department of Mathematics, Temple University

Jonathan Sprinkle, professor, Department of Computer Science, Vanderbilt University

Daniel Work, professor, Department of Civil and Environmental Engineering, Vanderbilt University

Nissan North America


General Motors