Existing signal control systems for urban traffic are usually based on traffic flow data from fixed location detectors.Because of rapid advances in emerging vehicular communication,connected vehicle(CV)-based signal c...Existing signal control systems for urban traffic are usually based on traffic flow data from fixed location detectors.Because of rapid advances in emerging vehicular communication,connected vehicle(CV)-based signal control demonstrates significant improvements over existing conventional signal control systems.Though various CV-based signal control systems have been investigated in the past decades,these approaches still have many issues and drawbacks to overcome.We summarize typical components and structures of these existing CV-based urban traffic signal control systems and digest several important issues from the summarized vital concepts.Last,future research directions are discussed with some suggestions.We hope this survey can facilitate the connected and automated vehicle and transportation research community to efficiently approach next-generation urban traffic signal control methods and systems.展开更多
This paper presents a fuzzy logic adaptive traffic signal control method for an isolated four-approach intersection with through and left-turning movements. In the proposed method, the fuzzy logic controller can make...This paper presents a fuzzy logic adaptive traffic signal control method for an isolated four-approach intersection with through and left-turning movements. In the proposed method, the fuzzy logic controller can make adjustments to signal timing in response to observed changes. The 'urgency degree' term that can describe different user's demands for a green light is used in the fuzzy logic decision-making. In addition, a three-level fuzzy controller model decides whether to extend or terminate the current signal phase and the sequence of phases. Simulation results show that the fuzzy controller can adjust its signal timing in response to changing traffic conditions on a real-time basis and that the proposed fuzzy logic controller leads to less vehicle delays and a lower percentage of stopped vehicles.展开更多
针对高峰时期公交专用道利用率较低的问题,提出一种基于信号预控的动态公交专用道策略,提升道路资源时空利用。在保证公交优先基础上对交通流构成比例进行影响分析,确定了APL、IBL和DBL三种常用车道控制模式适用范围;以路段人均时耗最...针对高峰时期公交专用道利用率较低的问题,提出一种基于信号预控的动态公交专用道策略,提升道路资源时空利用。在保证公交优先基础上对交通流构成比例进行影响分析,确定了APL、IBL和DBL三种常用车道控制模式适用范围;以路段人均时耗最小为目标函数,建立动态公交专用道规划模型,确定了各车道模式临界流量值;考虑交叉口信号差异下车道排队消散时长不同,构建基于信号预控下路段清空条件,实现公交专用道提前预控,建立了信号预控下动态公交专用道控制流程。以重庆市某段路为案例,选取全时段普通混合车道(all purpose lane,APL)、间歇式公交专用道(intermittent bus lane,IBL)和完全式公交专用道(dedicated bus lane,DBL)为参照,分别对实验路段和公交专用道进行评价分析。结果表明:本文动态公交专用道策略能够提高公交专用车道资源利用率,有效缓解公交优先和路段整体交通效率之间的矛盾。展开更多
为了在保证路段行人过街安全与过街需求的前提下,同时提升路段车辆运行效率,充分考虑了车队离散到达与路段行人过街的动态影响,建立了路段行人过街感应式信号控制方法。首先,基于Robertson车队离散模型,以车头时距对上游到达车队进行动...为了在保证路段行人过街安全与过街需求的前提下,同时提升路段车辆运行效率,充分考虑了车队离散到达与路段行人过街的动态影响,建立了路段行人过街感应式信号控制方法。首先,基于Robertson车队离散模型,以车头时距对上游到达车队进行动态划分,并根据路段行人过街点位预测下游车辆排队状态;以车队离散度选择下游到达车队中车辆作为信号优化输入参数建立感应控制方法,同时分析了路段行人过街位置对配时方案的影响;然后,通过SUMO软件的交通控制接口(traffic control interface,TraCI)搭建仿真环境,以车辆与行人的综合平均延误,分别对路段单向与双向交通环境的信号配时方案进行仿真验证与对比分析。结果表明,相比传统感应控制而言,优化后的感应控制在单向交通与双向交通情况下,行人与车辆综合平均延误分别降低5.56%、7.06%。展开更多
基金supported by National Key R&D Program of China(Grant No.2018YFE0204302)National Natural Science Foundation of China(Grant No.52062015,No.61703160)+1 种基金the Talent Research Start-up Fund of Nanjing University of Aeronautics and Astronautics(YAH22019)Jiangsu High Level'Shuang-Chuang'Project.
文摘Existing signal control systems for urban traffic are usually based on traffic flow data from fixed location detectors.Because of rapid advances in emerging vehicular communication,connected vehicle(CV)-based signal control demonstrates significant improvements over existing conventional signal control systems.Though various CV-based signal control systems have been investigated in the past decades,these approaches still have many issues and drawbacks to overcome.We summarize typical components and structures of these existing CV-based urban traffic signal control systems and digest several important issues from the summarized vital concepts.Last,future research directions are discussed with some suggestions.We hope this survey can facilitate the connected and automated vehicle and transportation research community to efficiently approach next-generation urban traffic signal control methods and systems.
基金Supported by the Major Research Project of theDepartm ent of Communication of China and ChinaPostdoctoral Science Foundation
文摘This paper presents a fuzzy logic adaptive traffic signal control method for an isolated four-approach intersection with through and left-turning movements. In the proposed method, the fuzzy logic controller can make adjustments to signal timing in response to observed changes. The 'urgency degree' term that can describe different user's demands for a green light is used in the fuzzy logic decision-making. In addition, a three-level fuzzy controller model decides whether to extend or terminate the current signal phase and the sequence of phases. Simulation results show that the fuzzy controller can adjust its signal timing in response to changing traffic conditions on a real-time basis and that the proposed fuzzy logic controller leads to less vehicle delays and a lower percentage of stopped vehicles.
文摘针对高峰时期公交专用道利用率较低的问题,提出一种基于信号预控的动态公交专用道策略,提升道路资源时空利用。在保证公交优先基础上对交通流构成比例进行影响分析,确定了APL、IBL和DBL三种常用车道控制模式适用范围;以路段人均时耗最小为目标函数,建立动态公交专用道规划模型,确定了各车道模式临界流量值;考虑交叉口信号差异下车道排队消散时长不同,构建基于信号预控下路段清空条件,实现公交专用道提前预控,建立了信号预控下动态公交专用道控制流程。以重庆市某段路为案例,选取全时段普通混合车道(all purpose lane,APL)、间歇式公交专用道(intermittent bus lane,IBL)和完全式公交专用道(dedicated bus lane,DBL)为参照,分别对实验路段和公交专用道进行评价分析。结果表明:本文动态公交专用道策略能够提高公交专用车道资源利用率,有效缓解公交优先和路段整体交通效率之间的矛盾。
文摘为了在保证路段行人过街安全与过街需求的前提下,同时提升路段车辆运行效率,充分考虑了车队离散到达与路段行人过街的动态影响,建立了路段行人过街感应式信号控制方法。首先,基于Robertson车队离散模型,以车头时距对上游到达车队进行动态划分,并根据路段行人过街点位预测下游车辆排队状态;以车队离散度选择下游到达车队中车辆作为信号优化输入参数建立感应控制方法,同时分析了路段行人过街位置对配时方案的影响;然后,通过SUMO软件的交通控制接口(traffic control interface,TraCI)搭建仿真环境,以车辆与行人的综合平均延误,分别对路段单向与双向交通环境的信号配时方案进行仿真验证与对比分析。结果表明,相比传统感应控制而言,优化后的感应控制在单向交通与双向交通情况下,行人与车辆综合平均延误分别降低5.56%、7.06%。
