摘  要

城市交通信號(hào)控制是通過(guò)對(duì)交通流量的調(diào)節(jié)以達(dá)到改善人和貨物的安全運(yùn)輸，提高運(yùn)營(yíng)效率。交通系統(tǒng)是一個(gè)具有隨機(jī)性、模糊性和不確定性的復(fù)雜系統(tǒng)，建立數(shù)學(xué)模型非常困難，有時(shí)甚至無(wú)法用現(xiàn)有的數(shù)學(xué)方法加以描述。目前大多采用的是自適應(yīng)信號(hào)控制，它需要數(shù)學(xué)建模，且不考慮交通延誤、停車(chē)次數(shù)等。所以經(jīng)典控制法很難得到滿意的效果。而模糊控制是一種無(wú)須建立數(shù)學(xué)模型的控制方法，它能模仿有經(jīng)驗(yàn)的交警指揮交通時(shí)的思路，達(dá)到很好的控制效果。近些年來(lái)我國(guó)的許多學(xué)者也都以不同的思路對(duì)單個(gè)交叉口、交通干線的模糊控制進(jìn)行了研究，但因研究的局限性，實(shí)際中得到應(yīng)用的寥寥無(wú)幾，本文實(shí)現(xiàn)基于PLC的交通信號(hào)的控制系統(tǒng)。

    根據(jù)前后相流量來(lái)決定信號(hào)燈配時(shí)的模糊控制系統(tǒng)的理論研究成果，用PLC實(shí)現(xiàn)單個(gè)十字路口交通信號(hào)燈模糊控制的方法，以單個(gè)十字路口4相位交通燈為例，把PLC作為一個(gè)模糊控制器，采用梯形圖編程。通過(guò)實(shí)驗(yàn)保證了系統(tǒng)運(yùn)行穩(wěn)定可靠，能根據(jù)不同的交通流量進(jìn)行模糊控制決策，優(yōu)化信號(hào)燈的配時(shí)，從而可以有效的解決交通流量不均衡、不穩(wěn)定帶來(lái)的問(wèn)題。

近年來(lái)隨著科技的飛速發(fā)展，一個(gè)以微電子技術(shù)、計(jì)算機(jī)技術(shù)和通信技術(shù)為先導(dǎo)的信息革命正在蓬勃發(fā)展。計(jì)算機(jī)技術(shù)作為三者之一，怎樣與實(shí)際應(yīng)用更有效的結(jié)合并發(fā)揮其作用。單片機(jī)作為計(jì)算機(jī)技術(shù)的一個(gè)分支，正在不斷的應(yīng)用到實(shí)際生活中，同時(shí)帶動(dòng)傳統(tǒng)控制檢測(cè)的更新。在實(shí)時(shí)檢測(cè)和自動(dòng)控制的應(yīng)用系統(tǒng)中，單片機(jī)往往是作為一個(gè)核心部件使用，針對(duì)具體應(yīng)用對(duì)象的特點(diǎn),配以其它器件來(lái)加以完善。靠的是交通信號(hào)燈的自動(dòng)指揮系統(tǒng)，來(lái)實(shí)現(xiàn)交通的井然有序。交通信號(hào)燈控制方式很多。本系統(tǒng)采用美國(guó)ATMEL公司生產(chǎn)的單片機(jī)AT89S51，以及其它芯片來(lái)設(shè)計(jì)交通燈控制。實(shí)現(xiàn)了通過(guò)AT89S51芯片的P1口設(shè)置紅、綠燈點(diǎn)亮的功能，通過(guò)AT89S51芯片的RXD、TXD輸入、輸出設(shè)置顯示時(shí)間。交通燈的點(diǎn)亮采用發(fā)光二極管實(shí)現(xiàn)，時(shí)間的顯示采用七段數(shù)碼管實(shí)現(xiàn)。單片機(jī)系統(tǒng)采用的直流供電。為了系統(tǒng)穩(wěn)定可靠，系統(tǒng)內(nèi)集成了“看門(mén)狗”芯片，避免了系統(tǒng)因?yàn)樗罊C(jī)而停止工作的情況發(fā)生。系統(tǒng)實(shí)用性強(qiáng)、操作簡(jiǎn)單、擴(kuò)展性好。

關(guān)鍵詞： 交通燈 PLC 智能控制

Abstract

City traffic signal control is through the adjustment of the traffic flow in order to improve the safety of transport of people and goods, improve operational efficiency. Transport system is a random, fuzzy and uncertainty of complex systems, it is difficult to build mathematical model, sometimes impossible to use existing mathematical methods described. At present most adaptive signal control is used, it needs mathematical model, without considering traffic delays, number of stops. So the classical control method is very difficult to get a satisfied effect. Fuzzy control is a kind of does not need to establish the mathematical model to control methods, it can imitate experienced police directing traffic, ideas, achieve good control results. In recent years, many Chinese scholars have different ideas of fuzzy control to the traffic single intersection, were studied, but because of the limitations of the research, application of scanty practice, the implementation of traffic signal control system based on PLC.

Decision fuzzy signal control system theory research results according to the method and flow, using PLC to achieve a single traffic lights at the crossroads of fuzzy control, the single crossroads 4 phase of traffic lights, for example, the PLC as a fuzzy controller, using ladder programming. Through the experiment to ensure the reliable operation of the system, can be fuzzy control decision according to the different traffic flow, optimize signal distribution, which can effectively solve traffic imbalance, instability problems.

In recent years, with the rapid development of science and technology, a microelectronics technology, computer technology and communication technology as the forerunner of the information revolution is booming. As one of the three computer technology, combined with practical application more effective and play its role. Single chip microcomputer as a branch of computer technology, has been applied to real life, and promote the traditional control detection update. In real-time detection and automatic control system, SCM is often used as a core component, according to the characteristics of the specific application object, match with other devices to be perfect. Relying on the automatic command system of traffic signal lamp, traffic in order to achieve. A lot of traffic signal control. This system uses the American ATMEL company AT89S51 microcontroller, and other chip to design the control of traffic lights. Through the implementation of the AT89S51 chip set P1 mouth red, green light function, through the AT89S51 chip RXD, TXD input, output is set to display the time. Traffic lights lit by the light emitting diode, the time display using seven digital tube. DC power supply used in SCM system. In order to the system is stable and reliable, the system integrates "watchdog" chip, to avoid the system crashed and stop work because of the situation. The system practical, simple operation, good scalability.

Key words：The traffic lights PLC intelligent control

 

目 錄

摘  要 I

Abstract II

1 引言 1

2 交通管理方案論證 2

2.1 設(shè)計(jì)任務(wù) 2

2.2 方案介紹 2

3 交通燈系統(tǒng)硬件設(shè)計(jì) 5

3.1 單片機(jī)概述 5

3.2 系統(tǒng)構(gòu)成 5

3.3芯片選擇與介紹 6

4 交通燈軟件設(shè)計(jì) 11

4.1 程序設(shè)計(jì)流程圖 11

4.2延時(shí)的設(shè)定 13

4.3 程序的主控制循環(huán)調(diào)用 15

4.4 對(duì)現(xiàn)有程序的擴(kuò)充 15

5實(shí)驗(yàn)平臺(tái) 17

5.1實(shí)驗(yàn)平臺(tái) 17

5.2實(shí)驗(yàn)步驟 17

結(jié)   論 19

致   謝 20

參考文獻(xiàn) 21

附   錄 22