Speed Advice for Connected Vehicles at an Isolated Signalized Intersection in a Mixed Traffic Flow Considering Stochasticity of Human Driven Vehicles

This paper introduces the common methods of delay analysis in signalized intersection. Focuses on point sample method (PSM), and puts forward the improved point sample method (IPSM) that is easier to actual operation and accurate. Because the control delay takes the place of the stop delay and the statistics of period takes the place of the statistics of moment. Apply the IPSM and the HCM delay model to analysis delay of signalized intersection in Hohhot. It is a linear relationship between the two results. And the applicability of the IPSM is verified. The IPSM is more applicable and accurate to the mixed-traffic flow in China.

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Inter-Green Time Design Method of Signalized Intersection under Mixed Traffic Flow Condition

CICTP 2020 ◽

10.1061/9780784482933.049 ◽

2020 ◽

Author(s):

Hailun Liang ◽

Xiaoguang Yang

Keyword(s):

Traffic Flow ◽

Flow Condition ◽

Design Method ◽

Signalized Intersection ◽

Mixed Traffic ◽

Mixed Traffic Flow

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How Does Heterogeneity Affect Freeway Safety? A Simulation-Based Exploration Considering Sustainable Intelligent Connected Vehicles

Sustainability ◽

10.3390/su12218941 ◽

2020 ◽

Vol 12 (21) ◽

pp. 8941

Author(s):

Yuntao Shi ◽

Ye Li ◽

Qing Cai ◽

Hao Zhang ◽

Dan Wu

Keyword(s):

Traffic Flow ◽

Dynamic Models ◽

Sustainable Transportation ◽

Individual Heterogeneity ◽

Model Parameters ◽

Connected Vehicles ◽

Mixed Traffic ◽

Cruise Control ◽

Negative Effects ◽

Mixed Traffic Flow

Intelligent connected vehicles (ICVs) are recognized as a new sustainable transportation mode, which could be promising for reducing crashes. However, the mixed traffic consisting of manually driven vehicles and ICVs may negatively affect road safety due to individual heterogeneity. This study investigated heterogeneity effects on freeway safety-based simulation experiments. Two types of vehicle dynamic models were employed to depict dynamic behaviors of manually driven vehicles and adaptive cruise control (ACC) vehicles (a simplified version of ICVs), respectively. Real vehicle trajectories were utilized to calibrate model parameters based on genetic algorithms. Surrogate safety measures were applied to establish the relationship between vehicle behaviors and longitudinal collision risks. Simulation results indicate that the heterogeneity has negative effects on longitudinal safety. With the higher degree of heterogeneity, longitudinal collision risks are increased. Compared to traffic flow consisting of human drivers only, mixed traffic flow may be more dangerous when the market penetration rate of ACC is low, since the ACC system can be recognized as a new source of individual heterogeneity. Findings of this study show that necessary countermeasures should be developed to improve safety for mixed traffic flow from the perspective of transportation safety planning in the near future.

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