The Smart Columbus Demonstration Program Evaluated the Performance of the Connected Vehicle Environment, a High-Speed Roadside and On-Board Wireless Communications Network for Vehicle Safety.
Primarily funded by the USDOT’s Smart City Challenge, the Smart Columbus Program is a collection of eight transportation, mobility and data studies aimed at improving access to jobs, enhancing tourism, stimulating the economy, connecting residents to safe and reliable transportation, and supporting efficient and sustainable movement of people and goods throughout Columbus. The Connected Vehicle Environment (CVE) study was one of the eight Smart Columbus studies with the goal to enhance safety and mobility for vehicle operators, both private and public, and to improve pedestrian safety in school zones. The CVE study deployed secure, high-speed wireless communication technology in 1,000 vehicles and at 85 signalized intersections along four district corridors to exchange critical situational data between the infrastructure and vehicles, and between individual vehicles. The collected data was then used to alert drivers of potential safety issues through a heads-up display via the following applications: Red Light Violation Warning, Reduced Speed School Zone Warning, Emergency Vehicle Preemption, Transit Signal Priority, Intersection Movement Assist, Lane Change Warning/Blind Spot Warning, Emergency Electronic Brake Light Warning, and Forward Collision Warning. The CVE launched in October 2020 and continued through May 31, 2021.
The key performance metrics that were collected by the CVE and stored for data analysis included hard braking events, instances of red light-running, approach speeds, and acceleration/deceleration, with data being captured at a rate of 65 million records per day. During the final months of the Smart Columbus Program and post-demonstration, survey responses were collected to evaluate the impacts of the CVE. Surveys were distributed to the public and private drivers of CV-equipped vehicles and the resulting feedback was combined with the performance metrics obtained from the CVE and stored on the Smart Columbus Operating System (SCOS).
The CVE Safety outcomes were successful in all three objectives, including emergency response times, awareness of signal status, and awareness in school zones:
- The CVE’s Emergency Vehicle Preemption application improved average speed and travel time for all approaches when preemption was granted, decreasing travel time by up to 5.6 seconds with an average of 1.64 seconds. Improvements to signal priority with the CVE additionally provided opportunities to reduce truck-related emissions and fuel consumption.
- Results suggest that the red-light warnings provided by the CVE prevented some crashes, especially when speeds exceeded 20 miles per hour more than 50 feet from an intersection. In this regime of cases, the average vehicle speed decreased by 2.3 miles per hour.
- The CVE increased compliance of posted speed limits in school zones from 18 percent to 56 percent. Thirteen percent of vehicles decreased to below the school zone speed limit (20 miles per hour) in under two seconds after a warning had been issued.
- Based on the survey results, 62 percent of private vehicle participants said they would recommend CV technology to friends and family, indicating an endorsement of further usage of the technology.