
I-24 MOTION
Testbed for traffic management and automated vehicle technologies
Located on 4 miles of Interstate 24 in Middle Tennessee
Data sharing begins in 2023

About I-24 MOTION
The I-24 Mobility Technology Interstate Observation Network (MOTION) is a four-mile section of I-24 in the Nashville-Davidson County Metropolitan area with 294 ultra-high definition cameras. Those images are converted into a digital model of how every vehicle behaves with unparalleled detail. This is all done anonymously using Artificial Intelligence (AI) trajectory algorithms developed by Vanderbilt University.
Vehicle trajectory data allows us to uncover new insights into how traffic flow influences individual vehicle behavior. This groundbreaking understanding of traffic is more important than ever due to the increasing automation capability of individual vehicles, which are beginning to influence traffic flow through their interactions with conventional vehicles. By unlocking a new understanding of how these vehicles influence traffic, vehicle and infrastructure design can be optimized to reduce traffic concerns in the future to improve safety, air quality, and fuel efficiency.
The purpose of I-24 MOTION is to provide an environment for testing advanced traffic management and automated vehicle technologies in real freeway traffic. Automakers and suppliers are investing billions of dollars in adding connectivity and automation features to vehicles, forever changing safety and mobility. These technologies are often developed in the laboratory or closed-course settings. Testing in traffic captures the variability of real-world conditions and human behavior. Complementary congestion management technologies are being installed by TDOT along this same section of interstate as part of the I-24 SMART Corridor project.
Using the information gathered on this testbed, I-24 MOTION will provide insights to allow the industry to build better products and allow TDOT to better understand how to make the most out of these products for managing infrastructure assets. The first testbed user is the U.S. Department of Energy’s sponsored research with the CIRCLES Consortium, which is studying the possibility of smoothing traffic by introducing vehicles equipped with advanced driver-assist systems.
Timeline
- 2018 – testbed needs and strategy established
- 2019 – camera technology pilot
- 2020 – construction of 3-pole ”validation system” to study design and feasibility
- 2021 – design and build begins for full system
- July 2022 – installation of Vanderbilt, TDOT 'I-24 MOTION' cameras nears completion
- Nov. 2022 – construction completes and testbed becomes operational
- Nov. 14-18, 2022 – CIRLCES experiment on I-24 MOTION
Experimentation: CIRCLES test on I-24 MOTION
The CIRCLES Consortium, consisting of Vanderbilt University, UC Berkeley, Temple University and Rutgers University-Camden, in coordination with Nissan North America and the Tennessee Department of Transportation, concluded a five-day open-track experiment on Nov. 18. Researchers tested an AI-powered cruise control system designed to increase fuel savings and ease traffic using 100 specially equipped Nissan Rogue vehicles.
The experiment—which ran from Nov. 14 through Nov. 18 on the I-24 MOTION testbed—is based on the results from an earlier, closed-track study where a single smart vehicle smoothed human-caused traffic congestion, leading to significant fuel savings. A single AI-equipped vehicle could influence the speed and driving behavior of up to 20 surrounding cars, causing a kind of positive ripple effect in day-to-day traffic.
On November 16 alone, I-24 MOTION testbed recorded a total of 143,010 miles driven and 3,780 hours of driving. The data from the testbed, combined with vehicle energy models developed in the CIRCLES project, provided an estimation of the fuel consumption of the whole traffic flow during those hours. “The concept we are hoping to demonstrate is that by leveraging this new traffic system to collect data and estimate traffic and applying artificial intelligence technology to existing cruise control systems, we can ease traffic jams and improve fuel economy,” the CIRCLES team said in a joint statement.
The CIRCLES Consortium research is supported by the National Science Foundation and the U.S. Departments of Transportation and Energy. Support was also provided by Toyota North America and General Motors.
