基于实时交通流的信号控制系统的设计与研究

发布时间：2019-02-13 12:52

【摘要】：近年来,随着我国城市化进程的加快,各类机动车保有量急剧攀升,交叉路口承载的负荷越来越大。传统的固定信号灯配时方案使车辆在交叉路口的滞留时间过长,而车辆在滞留期间会产生大量的二氧化碳气体,这对整个生态环境构成了巨大威胁。因此,一个合理的智能交通控制方案对于改善城市道路交通状况和提高城市生态环境质量具有现实意义。本文主要以实时交通流信息为前提,对城市道路中单个交叉路口处车辆的速度控制和交通信号灯控制方法进行了研究,旨在减少车辆经过交叉路口时的红灯等待时间以及车辆二氧化碳排放量。首先,本文概述了交通控制的发展历程,并对几个经典的道路交通控制系统优缺点进行了简要分析。由于车流的信息获取是交通系统控制的基础和前提,本文介绍了几种比较成熟的车辆信息检测技术。此外,本文还从数学的角度上对交叉路口进行了描述,分析并探讨了交通控制的基本概念以及交通控制优化决策方法。其次,本文提出了由速度控制模块和信号灯控制模块组成的单点控制系统。在速度控制模块中,车辆的速度和位置通过V2V和V2R通信方式发送给速度控制中心,根据交通信号灯当前的相位和剩余时间,驾驶者会收到一个相关的反馈速度,这样可以保证VANETs环境中的车辆即使在视距不够充足的情况下也能以最平滑的运动状态通过交叉路口。在信号控制模块中,借助于自适应巡航控制器的应用,控制对象由离散的车辆变为前后车间距可测的车队流,当车队的头节点车辆进入交叉路口的信息侦测范围时,车队中其它车辆的状态信息会以多跳的方式沿着车辆行驶的方向从后往前传输。根据接收到的实时交通流信息,以先进先出为基本原则,控制中心会生成相应的信号灯变化策略以最大程度上避免车辆停车等待红灯。通过MATLAB仿真实验可以得出结论,相对于传统的固定信号灯配时方案,本文提出的单点控制系统确实能够减少车辆经过交叉路口时红灯等待时间以及二氧化碳排放量。最后,本文结合实际的案例,通过VISSIM软件仿真分析指出了传统的固定信号灯配时方案存在的不足之处。在此基础上,将公交优先的信号控制策略与单点控制系统方案相结合,提出了一种基于快速公交优先的两级调度方案。根据MATLAB的仿真结果可以得出,在快速公交优先的前提下,该方案依然可以减少普通车辆通过交叉路口时的二氧化碳排放量。
[Abstract]:In recent years, with the acceleration of urbanization in our country, the number of various kinds of motor vehicles has risen sharply, and the load of intersection has become more and more heavy. The traditional fixed signal timing scheme makes the vehicle stay at the intersection for a long time, while the vehicle will produce a large amount of carbon dioxide gas during the detention period, which poses a great threat to the whole ecological environment. Therefore, a reasonable intelligent traffic control scheme is of practical significance for improving urban road traffic conditions and improving the quality of urban ecological environment. On the premise of real-time traffic flow information, this paper studies the methods of vehicle speed control and traffic signal light control at a single intersection of urban roads. The aim is to reduce red light waiting times and vehicle carbon dioxide emissions at intersections. Firstly, this paper summarizes the development of traffic control, and briefly analyzes the advantages and disadvantages of several classical road traffic control systems. As the traffic flow information acquisition is the basis and premise of traffic system control, this paper introduces several mature vehicle information detection techniques. In addition, this paper describes the intersection from a mathematical point of view, analyzes and discusses the basic concept of traffic control and the optimal decision method of traffic control. Secondly, this paper presents a single point control system composed of speed control module and signal control module. In the speed control module, the speed and position of the vehicle are sent to the speed control center via the V2V and V2R communication mode. According to the current phase of the traffic signal and the remaining time, the driver receives a related feedback speed. This can ensure that vehicles in VANETs environment can pass through the intersection in the smoothest state of motion even if the sight distance is not enough. In the signal control module, with the application of adaptive cruise controller, the control object is changed from discrete vehicle to vehicle flow which can measure the distance between front and rear vehicles. When the head node vehicle of the motorcade enters the information detection range of intersection, The status information of other vehicles in the motorcade is transmitted backward and forward in a multi-hop manner. According to the received real-time traffic flow information and based on the principle of first-in-first-out (FIFO), the control center will generate the corresponding signal change strategy to avoid the vehicle stopping and waiting for the red light to the greatest extent. The MATLAB simulation results show that compared with the conventional fixed signal timing scheme, the single point control system proposed in this paper can reduce the red light waiting time and the carbon dioxide emission when the vehicle passes through the intersection. Finally, combining with the actual cases, the paper points out the shortcomings of the traditional fixed signal lamp timing scheme through the simulation analysis of VISSIM software. On this basis, combining the signal control strategy of bus priority with the scheme of single-point control system, a two-level scheduling scheme based on bus rapid transit priority is proposed. According to the simulation results of MATLAB, it can be concluded that under the premise of bus rapid transit priority, the scheme can still reduce the carbon dioxide emissions of ordinary vehicles passing through intersections.
【学位授予单位】：扬州大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：U491.51

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