Assessing the Mobility and Environmental Benefits of Reservation-Based Intelligent Intersections Using an Integrated Simulator
This study developed an integrated simulation test bed that allowed new connected vehicle applications to be designed and evaluated. Defined as an "intelligent intersection" researchers devised an application that could take advantage of real-time vehicle situation data and manage intersection efficiency using a reservation-based strategy. Using wireless V2I communications vehicles approaching the intersection would connect with an automated intersection coordinator and reserve a time slot enabling them to pass through the intersection with minimal delay relative to prevailing traffic conditions. At times when reservations conflicted the intersection coordinator would notify vehicles to slow down as needed to make more slots available and then repeat the reservation request process. Overall the reservation system used a first-come-first serve logic, but incorporated vehicle situation data to optimize mobility for the majority of vehicles to improve intersection efficiency.
The study used a microscopic traffic network simulator and emissions model to emulate traffic at three signalized intersections in the town of Amherst, NY. Two of the signalized intersections were intersections of two major roads, whereas the third intersection was an intersection of a major road and a minor road. All vehicles in the network were assumed to be able to communicate autonomously with the system (once per second) and adjust speed if needed. Mobility and environmental impacts were measured with and without intelligent intersection controls. The base case demand level represented real-world field traffic counts collected in 2010.
Results indicated that a network of autonomous vehicles with full market penetration can use intelligent intersection data to manage approach speeds and reduce average vehicle delay by 85 percent.