基于plc的智能交通灯控制系统设计毕业论文 下载本文

二○一三届学生毕业论文(设计) 存档编号:__________

江 汉 大 学 毕 业 论 文(设计)

论 文 题 目 智能交通灯设计

(英 文) the design of intelligent traffic lights

学 院: 专 业:

姓 名: 学 号:

指导教师:

2013年05月26日

智能交通灯设计

摘 要

PLC可编程序控制器是以微处理器为基础,综合了计算机技术、自动控制技术和通讯技术发展而来的一种新型工业控制装置。它具有结构简单、编程方便、可靠性高等优点,已广泛用于工业过程和位置的自动控制中。据统计,可编程控制器是工业自动化装置中应用最多的一种设备。专家认为,可编程控制器将成为今后工业控制的主要手段和重要的基础设备之一,PLC、机器人、CAD/CAM将成为工业生产的三大支柱。由于PLC具有对使用环境适应性强的特性,同时其内部定时器资源十分丰富,可对目前普遍使用的“渐进式”信号灯进行精确控制,特别对多岔路口的控制可方便地实现。因此现在越来越多地将PLC应用于交通灯系统中。同时,PLC本身还具有通讯联网功能,将同一条道路上的信号灯组成一局域网进行统一调度管理,可缩短车辆通行等候时间,实现科学化管理。

关键字:交通灯 PLC 通讯 科学管理 渐进式

I

智能交通灯设计

Abstract

The programmable preface in PLC controller is a kind of new industry controls the device,it regard microprocessor as the foundation, synthesizing the calculator technique, automatic control technique to develop with the communication technique .It has the construction simple, the plait distance is convenient, high etc. in dependable advantage, already extensive used for the industry process with the automatic control of the position inside.According to the covariance, the programmable controller is a kind of equipments that industry automate to equip the inside the application at most.The expert thinks, the programmable controller will become the main means that aftertime industry control with the one of the important foundation equipmentses, the PLC, robot, CAD/ CAM will become three major of pillar that industry produce.Because the PLC has to the strong characteristic in adaptability in environment in usage, its inner part settles at the same time the machine resources is abundant very, can to current widespread usage of\enter the type gradually\the signal beacon proceeds the precision controls, special the oscular control in a many branch roads can realizes expediently.So that is applied the PLC more and more now in transportation light system inside.At the same time, PLC still have the communication internet function, constitute the same of the signal beacon on the road a the bureau area net proceeds to unify to adjust a management, can shorten the vehicle go through waiting time, realizing scientific management.

Keywords: The transportation light, PLC , Communication,scientific management,enter the type gradually

II

智能交通灯设计

目 录

第一章 绪论···························································1

1.1 引言································································1 1.2 智能交通灯系统的发展背景·········································1 1.3 本课题的主要研究内容·············································2

第二章 PLC的功能介绍··············································4

2.1 PLC的基本概念和基本结构·········································4 2.2 PLC的特点和应用领域··············································6 2.3 PLC的工作原理·····················································7 2.4 PLC的性能指标和软件系统······································?9

第三章 基于PLC的智能交通灯控制系统设计·················11

3.1 PLC型号的选定以及可行性分析····································11 3.2 光电计数器与选型·················································11 3.3光电计数器的铺设·················································12 3.4设计思路···························································13 3.5 I/O地址的分配····················································17 3.6交通灯各种情况的时序分析········································18 3.7主程序的设计······················································19 3.8运行与调试························································30

第四章 总结与展望··················································31 参考文献································································32 致谢······································································33

智能交通灯设计

第一章 绪 论

1.1 引言

交通灯控制系统的发展有着悠久的历史,伴随着人类工业文明的发展,汽车以及其他各种交通工具呈现出一片欣欣向荣的景象。各种交通工具的大量使用使得人们的出行更加方便,但随之而来的是交通的压力越来越大,各个路口对于对于交通指挥系统的需求大量增加。早在1868年,全世界第一台煤气是红绿两色照明灯由英国工程师纳伊特安装在了伦敦威斯特敏斯特街口,它可以控制车辆的通行,但是不久,这种交通灯便消身匿迹了,原因是由于一场爆炸事故。盗了1914年左右,交通灯又重新出现了,美国的克利夫兰制造了一款由电力驱动的交通灯,它被安装在了纽约和芝加哥等地,这种交通灯的概念已经和现在大致相同。1926年,自动化控制的交通灯得到利用,这为现代城市交通奠定了基础。1968年,联合国《道路交通和道路标志信号协定》对交通灯的各种意义做出了明确的规定,绿灯行,绿灯车道的车辆可直行可左拐可右拐,如果前面有禁止标志的则除外。并且左右拐弯的车辆必须让直行车辆和行人先行。红灯停,红灯车道的车辆不准超过人行道。黄灯等一等,黄灯车道的车辆必须减速,但车辆已十分接近停车线而不能安全停车时可以进入交叉路口。交通灯的使用大大缓解了交通压力,使得城市的拥堵显现得到了一定程度的缓解,使人们的出行现状得到了改善。但是随着当今经济的飞速发展,汽车的拥有量不断上升,传统的交通灯系统已经越来越不能满足交通压力的需求。在这样的背景下,本次论文设计的任务主要是设计一款能根据路面车流量的变化,进而调整交通灯读秒时间的交通灯系统,从而改善路面交通压力,同时也可以节约交通资源。

1.2智能交通灯系统的发展背景

1.2.1英国TRANSYT路面交通控制系统

英国道路研究所花费了十几年的时间,在大量的实验和经验的基础之上,研制出了TRANSYT路面交通控制系统。被全球400多个车市广泛采用,可以说TRANSYT系统的成功是显而易见的。TRANSYT内部通过有线来经行通信。采用静态模式来控制交通信号灯,这种控制方案中通过数学模型来控制绿信比和相位差。但是这种交通控制系统还是存在一定的缺陷,例如它无法优化周期,而且想要获得最优的整体分配方案是相当困难的。如果想要经行离线优化,必须采用大量的路网几何和交通数据流。

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