School buses that have priority at intersections can save time, boost fuel efficiency and enhance student safety, a pilot program shows.
A pilot program in Alpharetta, Georgia, tested connected vehicle-to-everything (C-V2X) technology provided by Applied Information that allowed two Fulton County School System buses to request green light priority at 62 traffic signals along their routes.
A recent report prepared by engineering consultant Kimley-Horn for Applied Information, indicated that the technology improved bus route efficiency. On average the number of unscheduled stops decreased by 40% and the average bus speeds increased by 18%. Fewer stops enhanced student safety, the study suggested, as children are more likely to stay seated when the bus is moving. Additionally, there was a reduction in both buses’ fuel consumption and emissions, indicating the county can save on fuel expenditures as well as foster healthier air conditions.
Data sources for the report included data loggers, fuel logs and interviews with participating bus drivers to conduct a before and after analysis of the pilot program.
As part of the program, 62 field monitoring units were installed at intersections, and each bus – one diesel-fueled and the other propane-fueled – carried an onboard unit. Applied Information configured the FMUs and OBUs to communicate with its cloud-hosted, web-based Glance traffic and infrastructure management software, according to the report.
Along the route, the OBU logged and transmitted the buses’ GPS coordinates to the Glance software every five seconds. As the bus approached a stop light, the FMU requested priority service from the local traffic signal controller, which would then either extend the current green light phase or shorten the opposing green phase, so the bus could get through the intersection more efficiently, the report explained.
“Where [the bus] was in relationship to the traffic intersection and how fast it was going and approaching the intersection – that information was all transferred to the intersection and not only the traffic intersection that’s immediately in front of the bus, but the traffic intersection that’s further down the road…” Brian Mulligan, CEO of Applied Information, said in a webinar. Long before the bus nears the signal, “the traffic intersection is figuring out does it have pedestrians in the crosswalk? Does it need to clear them? Does it need to truncate phases and so forth to safely turn the lights green for the school bus just before the school bus gets there, but with minimum disturbance of the traffic,” he said.
The technology helped reduce stress on the bus drivers to stay on schedule, allowing them to focus on safe driving practices and monitor students on board, Trey Stow, director of transportation operations for Fulton County Schools, said in the webinar. An added benefit is that students more often arrived at school in time to participate in the school’s breakfast program, which could help them learn and pay attention better, Stow said.
The C-V2X technology enables officials to reoptimize bus routing and reduce vehicle wear and tear, potentially reducing the number of buses and drivers needed, which may help address the nationwide bus driver shortage, officials said in an announcement.
“With about 86% of the nation’s school districts experiencing a driver shortage, improving the safety and efficiency of the fleet is critical,” Stow said in the announcement. “The pilot showed we can use this technology to make our fleet more efficient and serve more students safely in a shorter amount of time, all while reducing our fuel bill and helping the environment.”
Other partners in the program were IC Bus, the city of Alpharetta, Metro Trafix, Temple, Inc., HEM Data, Blue Bird and Infrastructure Automotive Technology Laboratory.