A Dynamic CAV-Dedicated Lane Allocation Method With the Joint Optimization of Signal Timing Parameters and Smooth Trajectory in a Mixed Traffic Environment

Abstract

Owing to the difference in utilization efficiency of road between a connected-automated vehicle (CAV) and connected human-driven vehicle (CHV), caused by trajectory controllability, the optimization methods reported in literature for the mixed traffic of CAVs and CHVs at signalized intersections do not consider the dynamic adjustment of the approach lane utilization due to variations in the CAV penetration rate and traffic demand. Accordingly, a dynamic CAV-dedicated lane allocation method with the joint optimization of signal timing parameters and smooth trajectory is proposed to avoid using transitional or inefficient CAV-dedicated lanes and improve the performance of the intersections. In addition, a CAV trajectory control model for the CAV-dedicated lane is built to avoid the start-up loss time and maximize the utilization of green time. The delay and stops are weighted to form an integrated performance index (PI), and a PI model is established to evaluate the proposed method. A simplified solution procedure is designed to solve the joint optimization problem. The simulation results show that the proposed method in this paper can reduce the average PI per vehicle at intersections by 15.7% or more compared with that of a fully actuated signal control scheme, which indicates that it is necessary to drive the CAVs in one or more CAV-dedicated lanes when the CAV penetration rate exceeds a certain threshold. Compared with the existing signal and trajectory control approaches, the proposed method is more suitable for multi-lane signalized intersection with high saturation and high CAV penetration rate.