Integrated optimization of traffic signals and vehicle trajectories at intersection with the consideration of safety during signal change

Abstract

This paper develops an integrated optimization of traffic signals and vehicle trajectories. The signal is optimized to improve the intersection efficiency and the calculation of intergreen interval (IGI) serves as constraints to guarantee vehicle safety during signal changing. Then the vehicle trajectory in the approach lane and inside intersection is optimized to increase fuel efficiency. The proposed method is evaluated by microscopic simulation, comparing with the actuated signal control (ASC) method and an ad hoc cooperation method between traffic signals and vehicles. Results indicate the proposed control algorithm is effective to prevent conflicts during signal changing periods. Operation Efficiency and fuel efficiency are improved. The benefit is 24.9% on vehicle delay, and is 5.5% on fuel efficiency. The proposed system can potentially be used in real-time.