Joint optimization of vehicle-group trajectory and signal timing: Introducing the white phase for mixed-autonomy traffic stream. (July 2020)

• Record Type: Journal Article
• Authors: Niroumand, Ramin; Tajalli, Mehrdad; Hajibabai, Leila; Hajbabaie, Ali
• Is Part Of: Transportation research. Volume 116(2020)
• Publication Date: 2020-07
• Subjects: Connected and automated vehicle -- White phase -- Mixed-autonomy traffic -- Selfdriving vehicles; Transportation -- Periodicals; Transportation -- Technological innovations -- Periodicals; 388.011
• DOI: 10.1016/j.trc.2020.102659
• Languages: English
• ISSNs: 0968-090X

Abstract

Highlights: Jointly controlling vehicle trajectory and signal timing in mixed human-driven and automated vehicle flows. Introducing a new white phase to enforce following immediate front vehicle. Using traffic lights as stationary and connected automated vehicles as moving controllers. Customizing a car-following model to incorporate signal control variables into the formulation. Utilizing white phase yields significant improvements in traffic operations. Abstract: This study develops a novel mixed-integer non-linear program to control the trajectory of mixed connected-automated vehicles (CAVs) and connected human-driven vehicles (CHVs) through signalized intersections. The trajectory of CAVs is continuously optimized via a central methodology, while a new "white" phase is introduced to enforce CHVs to follow their immediate front vehicle. The movement of CHVs is incorporated in the optimization framework utilizing a customized linear car-following model. During the white phase, CAVs lead groups of CHVs through an intersection. The proposed formulation determines the optimal signal indication for each lane-group in each time step. We have developed a receding horizon control framework to solve the problem. The case study results indicate that the proposed methodology successfully controls the mixed CAV-CHV traffic under various CAV market penetration rates and different demand levels. The results reveal that a higher CAV market penetration rate induces more frequent white phase indication compared to green-red signals. The proposed program reduces the total delay by 19.6%–96.2% compared to a fully-actuated signal control optimized by a state-of-practice traffic signal timing optimization software.