融入公交车与自动驾驶车队的异质交通流模型

Integrated Heterogeneous Traffic Flow Model of Bus and Autonomous Vehicle Platoon

为研究网联自动驾驶车(connected autonomous vehicle,CAV)和人工驾驶车(human-pilot vehicle,HPV)所组成的异质交通流特性及公交车驾驶行为对环境的影响,首先,分析异质交通流中的4种跟驰模式:人工驾驶小汽车跟驰、人工驾驶公交车跟驰、自适应巡航控制(adaptive cruise control,ACC)跟驰和协同自适应巡航控制(cooperative adaptive cruise control,CACC)跟驰;接着,基于各跟驰模型的特点,构建车辆跟驰和换道的元胞自动机模型,综合考虑CAV车队特性、驾驶员与CAV各自反应时间特性以及HPV加塞特性,并利用跟驰模式判断参数融合不同跟驰模式特性,实现统一的模型表达;最后,仿真分析不同CAV渗透率下CAV排队强度及公交车换道行为对交通流的影响.结果表明:在一定的CAV渗透率下,促使CAV形成队列比单纯提高CAV渗透率更能有效提升道路通行效率;适量的公交换道有助于充分利用道路通行能力,过多的公交换道则会妨碍正常交通,公交换道对交通流造成的通行效率衰减随CAV渗透率的增大而减小;同步流状态下,人工驾驶小汽车执行率与道路通行效率呈负相关关系;而在堵塞流状态下,人工驾驶小汽车执行率对通行效率影响甚微.

In order to investigate the heterogeneous traffic flow characteristics formed by the combination of connected autonomous vehicles(CAVs)and human-pilot vehicles(HPVs),as well as the impact of bus driving behavior on this environment,four following modes in heterogeneous traffic flow are initially analyzed:humanpilot car following,human-pilot bus following,adaptive cruise control(ACC)following,and cooperative adaptive cruise control(CACC)following.Subsequently,based on the characteristics of each following model,a cellular automaton model for vehicle following and lane-changing is constructed,which comprehensively considers the characteristics of CAV platoons,the response time characteristics of drivers and CAVs,and the cutting-in behavior of HPVs.By setting the following mode judgment parameters,different following mode characteristics are integrated to achieve a unified model representation.Lastly,through simulation experiments,the queuing intensity of CAVs at different penetration rates and the impact of bus lane-changing behavior on traffic flow are analyzed.The results indicate that promoting CAVs to form platoons at a certain penetration rate is more effective in improving road traffic efficiency than merely increasing the CAV penetration rate;a moderate amount of bus lane-changing contributes to the full utilization of road traffic capacity,while excessive bus lanechanging hinders normal traffic.The traffic efficiency attenuation caused by bus lane-changing decreases as the CAV penetration rate increases;under synchronized flow conditions,the execution rate of human-pilot cars is negatively correlated with road traffic efficiency;however,under congested flow conditions,the impact of human-pilot car execution rate on traffic efficiency is negligible.