基于嵌入式技术车辆信息检测装置设计 - 图文

摘要

摘要

智能交通系统利用尖端的电子信息技术，构成人员、车辆和公路三位一体的新型公路交通系统。它将先进的计算机处理技术、信息技术、数据通信传输技术、 自动控制技术、人工智能及电子技术等有效地综合运用于交通运输管理体系中，建立一种在大范围内、全方位发挥作用的准时、准确、高效的交通运输管理体系。本文着重研究了智能交通系统中的道路交通检测系统，设计了基于环形线圈的车辆检测器。采用双环形线圈检测技术，对车辆通过线圈时检测电路所产生的振荡频率进行数据分析，从而完成车流量监测。本文介绍了一种基于单片机的环形线圈车辆检测器系统，并分析了系统的结构和功能。该系统的硬件主体以 AT89C51为控制核心。实现了路面动态交通数据的采集，采集到的数据实时反映了车辆的通过或存在状况。该系统结构简单，操作容易，能较精确地检测出车辆的存在，可应用于交通检测和道路监控领域。最后给出了该检测器详细的软硬件设计方案。

关键词：智能交通系统；环形线圈；交通流检测；AT89C51

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Abstarct

Abstract

Intelligent Transportation Systems is a new highway traffic system, which is the trinity of personnel, vehicles and road, using sophisticated electronic information technology. ITS is a kind of systems combined with the advanced computer technology, information technology Data-communication technique, auto control art, artificial intelligence and electronic technology etc. It has been applied in traffic transportation management system, helps to establish a wide-extent, whole-direction, accurate, punctual, efficient traffic-transportation management system. This thesis studies emphatically on the traffic detector of intelligent transportation system. We designed the loop induction detector by using double loop detection technology. when vehicle goes through the loop, the waffle detectors gather the data of oscillation frequency by analyze the difference of frequency characteristics, thus we finished the test for cars. This thesis introduces a loop detector system which is based On microntoller, and analyzes the structure and function this system. The part of the hard—ware in this system is chiefly controlled by C8051, this system realizes the dynamic traffic information collection, and the collected data eflect the pass or existence condition of the vehicles real-timely. This systems simple, and is easy to perate it can detect vehicles precisely, and can be used in the highway traffic flow detection and the road security system. The design of hardware and software of this detector is given.

Key Words: intelligent transportation. n system(ITS); 1oop; traffic flow Detection; C8051.

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目录

目录

1 绪论 ................................................................... 1

1.1 车辆检测系统概述 ................................................. 3 1.2 传统车辆检测系统的不足 ........................................... 4 1.3 我国车辆检测系统的发展状况 ....................................... 5 1.4 研究的意义 ....................................................... 6 2 车辆检测器结构 ......................................................... 7

2.1 地感线圈车辆检测器 ............................................... 7 2.2 地感线圈车辆检测器基本原理 ....................................... 7 2.3 检测器的组成 ..................................................... 9

2.3.1 中央处理器 .................................................. 9 2.3.2 检测卡 ...................................................... 9 2.4 检测器协议的架构 ................................................ 10 2.5 检测器的算法概述 ................................................ 10 2.6 监控系统车辆检测器的综合评比 .................................... 10 3 地感线圈检测器实际操作 ................................................ 12

3.1 检测方法 ........................................................ 12 3.2 车辆检测器的埋地方法车辆检测器的埋地方法 ........................ 14 3.3 地感线圈检测器的电磁感应工作原理 ................................ 15 3.4 阈值的选取 ....................................................... 16 3.5 线圈检测的方法介绍 ............................................... 17 4 感应线圈交通流检测系统硬件设计 ........................................ 19

4.1 系统硬件结构系统硬件结构 ........................................ 19 4.2 锁相环工作原理 .................................................. 21

4.2.1鉴相器 ...................................................... 22 4.2.2环路滤波器 .................................................. 23 4.2.3压控振荡器 .................................................. 25 4.3 信号输入电路的设计 .............................................. 27 4.4 复位电路设计 .................................................... 29 4.5 整形电路设计 ................................................... 30 4.6 显示电路设计 .................................................... 31

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目录

5 地感线圈交通检测系统软件设计 .......................................... 32

5.1 设计时需要注意的几点 ............................................ 32 5.2 程序流程图程序流程图 ............................................ 33 结论 .................................................................... 34 致谢 .................................................................... 36 参考文献 ................................................................ 37 附录 .................................................................... 39

总体电路原理图 ....................................................... 39 总流程图 ............................................................. 40

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