A variable time headway model for the mixed car-following process considering multiple front vehicles information in foggy weather  

作　　者：Ziwei Liang Mingbao Pang 

机构地区：[1]Department of Transportation,School of Civil and Transportation,Hebei University of Technology,Tianjin 300401,China

出　　处：《Transportation Safety and Environment》2024年第4期140-155,共16页交通安全与环境(英文)

基　　金：supported by the National Natural Science Foundation of China(Grant No.50478088);the Science and Technology Project of Hebei Education Department in China(Grant No.ZD2021028);the Cooperation Special Project of Beijing-Tianjin-Hebei Basic Research in China(Grant No.F2024202106).

摘　　要：The aim of this work is to investigate the fog-related variable time headway(FVTH)model of connected and automated mixed flow considering multiple front vehicles information in a reduced visibility environment for driving safety.The car-following modes of mixed vehicles are analysed and the vehicle ratio for each mode based on Markov chain models is derived,where the number of front vehicles,the connected and automated vehicles penetration rate and the platoon intensity are considered.The combined coupling effect of visibility and driving speed on time headway is explored,and a variable time headway strategy is proposed.Their relationship equations are deduced as the FVTH model.The perturbation method is used to discuss the stability of traffic flow and obtain its stability judgement conditions.The proposed model was validated and the effects were discussed via simulation experiments.The results indicate that the acceleration and deceleration times of vehicles and collision possibility decrease significantly using the proposed method.When penetration rate is 50%,the number of front vehicles is three and platoon intensity is zero,the time to return to a stable state is reduced by 18.9%-30.3%and 24.7%-39.4%,respectively,and Time-Exposed Time to collision is reduced by 26.1%-48.9%and 43.7%%-65.4%,respectively,compared with the basic intelligent driver model(IDM)method,and the IDM method that considers multiple front vehicles information.As visibility decreases,the reduced degree of these indicator values increases.The driving efficiency and safety level can be enhanced.

关 键 词：connected and automated vehicles(CAVs) variable time headway model mixed traffic flow foggy weather multiple front vehicles information 

分 类 号：U49[交通运输工程—交通运输规划与管理]