Optimization-Based Intersection Control for Connected Automated Vehicles and Pedestrians

Abstract

Traffic at larger or busier urban intersections is currently coordinated using traffic signals to prevent dangerous traffic situations and to regulate the flow of traffic. In future scenarios with 100% connected automated vehicles, conventional traffic signals could be replaced, and vehicles at intersections could be seamlessly coordinated via vehicle-to-vehicle and vehicle-to-infrastructure communication. In the past two decades, many such control strategies have been presented, commonly referred to as autonomous intersection management (AIM). In recent years, an evolution from simpler first come, first served to more sophisticated optimization-based AIM strategies can be observed. Optimization-based AIM can significantly improve capacity and reduce delays as compared to slot-based strategies and conventional traffic signal control (TSC). In addition, it allows for prioritizing road users. This paper is among the first to consider pedestrians in optimization-based AIM. The proposed approach consists of a signal-free vehicle control in combination with pedestrian signal phases that are fully integrated into the optimization problem. Since the communication range of the controller is limited in real-world applications, a rolling horizon scheme is presented and explained in detail. The presented strategy is implemented and evaluated using a microscopic traffic simulation framework. Results show that vehicle delays can be significantly reduced and vehicle capacity can be increased compared to fully actuated TSC, while pedestrian waiting times are comparable. In addition, focus is put on how vehicle and pedestrian delays can be balanced in the presented setup. Three different control parameters can be adjusted, which need to be tuned based on the considered demand scenario.

Characterizing Behavioral Differences of Autonomous Vehicles and Human-Driven Vehicles at Signalized Intersections Based on Waymo Open Dataset

“…(ii) During the acceleration phase (phase IV), the average acceleration for AVs is around 1.09 m/s 2 , which is within the range specified in the literature (26). The maximum acceleration is about 2.02 m/s 2 , which is lower than the value assumed for AVs in Niels et al (19) (3.0 m/s 2 ), but higher than the upper acceleration for AV in S xentu¨rk Berktas x and Tanyel (12) (1.4 m/s 2 ). The starting response time to green light of HDVs is 0.70 s, which is slightly shorter than Clement et al (17) and Abraham (20), which reported values between 0.8 and 0.9 s. Contrary to the much shorter response time expected in the literature (19,13,20), it is 1.01 s for AVs which is comparable to or slightly longer than HDVs (6).…”

“…The maximum acceleration is about 2.02 m/s 2 , which is lower than the value assumed for AVs in Niels et al ( 19 ) (3.0 m/s 2 ), but higher than the upper acceleration for AV in Şentürk Berktaş and Tanyel ( 12 ) (1.4 m/s 2 ). The starting response time to green light of HDVs is 0.70 s, which is slightly shorter than Clement et al ( 17 ) and Abraham ( 20 ), which reported values between 0.8 and 0.9 s. Contrary to the much shorter response time expected in the literature ( 19 , 13 , 20 ), it is 1.01 s for AVs which is comparable to or slightly longer than HDVs ( 6 ). In addition, some HDVs have a response time that is shorter than 0 s, meaning that they anticipate the green light and tend to react before the light turns green.…”

“…However, AVs without communication with traffic signal infrastructure or other vehicles cannot achieve a short response time ( 12 ). In the literature, the response time for AVs was suggested to be around 0.6 s ( 19 ), and the smallest default value in the AIMSUN program is 0.75 s ( 13 ). Abraham ( 20 ) employed 0 s of response time for AVs and 0.8 s for HDVs.…”

“…For human drivers, 1.5 m/s 2 ( 24 ), 1.45 m/s 2 ( 25 ), and 0.83 to 1.43 m/s 2 ( 26 ) were suggested in the literature. Niels et al ( 19 ) assumed the maximum acceleration rate for an AV to be 3.0 m/s 2 . Şentürk Berktaş and Tanyel ( 12 ) applied the upper and lower acceleration values for AV as 1.40 m/s 2 and 0.75 m/s 2 .…”