Networkwide Impacts of Vehicle Ecospeed Control in the Vicinity of Traffic Signalized Intersections

Ecospeed control is an advanced ecodriving or ecovehicle control algorithm that uses signal phasing and timing information from signalized intersections to generate fuel-optimum vehicle trajectories. The proposed algorithm uses connected vehicles technology to communicate between vehicles and the infrastructure. The research presented in this paper integrates the algorithm with state-of-the-art traffic simulation software, in this case the INTEGRATION software, to develop a tool capable of analyzing and evaluating systemwide impacts. The algorithm uses dynamic programming to generate fuel-efficient vehicle trajectories in the vicinity of traffic signalized intersections by controlling the vehicle variable limiting speed (VLS) to minimize fuel consumption while maintaining safe car-following behavior. Ecospeed control uses constraints upstream and downstream of the intersection to generate a longitudinal VLS function. Multiple simulations for levels of congestion (volume-to-capacity ratios) and levels of market penetration suggest that the average fuel savings per vehicle are in the range of 26% when all vehicles are equipped with such systems. Similarly, the average reduction in total delay reaches 65% within the vicinity of traffic signalized intersections. The results also demonstrate that at levels of market penetration less than 50%, the system does not produce systemwide fuel and delay savings. In addition, the savings are higher for lower levels of traffic congestion.