混入智能车的下匝道瓶颈路段交通流建模与仿真分析  

Hybrid traffic flow model for intelligent vehicles exiting to off-ramp

作　　者：董长印 王昊 王炜 李烨 华雪东 Dong Chang-Yin;Wang Hao;Wang Wei;Li Ye;Hua Xue-Dong(Jiangsu Key Laboratory of Urban Intelligent Traffic System,School of Transportation,Southeast University,Nanjing 210096,China;Jiangsu Province Collaborative Innovation Center of Modern Urban Traffic Technologies,Nanjing 210096,China;School of Architecture,Southeast University,Nanjing 210096,China)

机构地区：[1]东南大学交通学院城市智能交通江苏省重点实验室,南京210096 [2]现代城市交通技术江苏高校协同创新中心,南京210096 [3]东南大学建筑学院,南京210096

出　　处：《物理学报》2018年第14期173-187,共15页Acta Physica Sinica

基　　金：国家自然科学基金(批准号:51478113;51508122);江苏省博士后科研资助计划(批准号:1701082B);东南大学优秀博士学位论文培养基金(批准号:YBJJ1734)资助的课题~~

摘　　要：以下匝道瓶颈路段为研究背景,以手动驾驶汽车和两类智能车为研究对象,包括自适应巡航(ACC)汽车和协同自适应巡航(CACC)汽车,建立了混入智能车的混合交通流模型.在车辆的纵向控制层面,分别构建了手动驾驶汽车改进舒适驾驶元胞自动机规则和智能车的跟驰模型;基于车辆下匝道行驶特性,引入车辆感知范围R、换道控制区域LLC、换道冒险因子λ等参数,建立了控制车辆横向运动的自由换道和强制换道模型.通过对混合交通流模型进行数值仿真发现,CACC车辆混入率PCACC、车辆感知范围R、换道区域长度LLC和换道冒险程度λ均对下匝道交通系统产生影响.当CACC车辆混入率低于0.5时,CACC退化为ACC的概率增大,系统稳定性下降,交通拥堵呈恶化趋势;当CACC车辆混入率大于0.5时,车辆运行速度显著提升,拥堵消散能力提高.增大车辆感知范围、加长换道区域长度、提高换道冒险程度,都能够有效缓解改善下匝道瓶颈路段主线的拥挤状况,而对匝道运行效率影响并不明显.With the rapid development of vehicular technology, hi-tech manufacturing facilities are equipped in intelligent vehicles to improve road capacity and traffic safety. However, freeway diverge segment has significant influence on current traffic flow, and could affect the heterogeneous traffic flow consisting of manual and intelligent vehicles. The primary objective of this study is to evaluate how intelligent vehicles affect traffic flow at an off-ramp bottleneck.In order to depict the car-following dynamics of manual vehicles, the modified comfortable model, one of the most classic cellular automata models, is employed to distinguish intelligent vehicles. In this paper, intelligent vehicles consist of adaptive cruise control（ACC） vehicles cooperative adaptive cruise control（CACC） vehicles. The ACC and CACC model are proposed by partners for advanced transportation technology（PATH）, which are validated by real experimental data. Besides, vehicles equipped with CACC will degrade ACC vehicle if the leading vehicle is driven manually. From the perspective of vehicle＇s lateral movement, two novel lane-changing models, including the discretionary lane-change（DLC）model and mandatory lane-change（MLC） model, are developed to model the future behaviors of intelligent vehicles. A risk factor λ is introduced into the DLC model to distinguish vehicles from conventional ones. Based on environment perception technology, a five-step MLC decision-making model is designed specifically for intelligent vehicles exiting to off-ramp. It is comprised of environment perception, safe gap computation, measured gap ranking, measured gap classification and lane-changing gap selection. Based on the proposed hybrid traffic flow model, numerical simulations are conducted to study the influences of intelligent vehicles on the traffic flow near an off-ramp. Apart from the market penetration of intelligent vehicles, parameters considered in this paper include the demands of mainlines and off-ramp,range of environment perce

关 键 词：智能车 换道模型 下匝道路段 自适应巡航控制 

分 类 号：U491[交通运输工程—交通运输规划与管理]