汽车车型进行自动识别系统设计

专科生毕业设计（论文）

摘 要

目前由于交通建设的高速发展，公路，桥梁等收费有偿类交通设施的建设越来越多，相应对其交通控制管理及收费方式的要求也在不断提高。目前车型的大小主要靠人工判断，还没有达到智能化。如果能够对汽车车型进行自动识别，就可以为公路的智能化收费系统的实施解决了关键问题。所以本系统针对以上问题进行设计。

本文简要介绍了8位单片机AT89S52，并详细阐述了利用单片机实现车辆车型自动检测的设计方案。主要以超声波传感器为检测元件；下位机与主PC机通信所构成的系统。AT89S52单片机作为整个下位机系统的核心，通过软件编程，来采集车辆信息从而达到车型的自动识别与收费控制。

本系统可分为硬件设计和软件设计两部分。在硬件设计部分对系统主要组成，设计方法选择做了详细阐述。硬件电路由单片机、显示电路、报警电路、检测电路、电源电路、栏杆控制电路组成。软件部分采用汇编语言编写。软件设计中给出了程序的流程图、初始化程序、以及检测程序、控制程序。

关键词：单片机AT89S52；超声波传感器；RS232；车型检测

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专科生毕业设计（论文）

Abstract

As the current rapid development of transportation construction, highways, bridges and other fees paid transport facilities such as the construction of more and more, corresponding to its traffic control management and pricing requirements are also rising. The current models rely mainly on the size of judgement, has not yet reached intelligent. If the Automatic Vehicle Identification, we can intelligent highway system in the implementation of the settlement of the key issues. Therefore, the system designed for the above-mentioned problems.

System gave a briefing on 8-bit microcontrollers AT89S52, and elaborate on the use of MCU vehicle inspection system design. Focused on the practical applications of SCM in the merits. Introduced to ultrasonic sensors to detect components; under the crew and the main phase of PC communications systems. AT89S52 SCM as a whole under the crew the heart of the system, through software programming, to collect information vehicles to reach the semi-automatic charging the purpose.

The system can be divided into the design of hardware and software design in two parts. System and the main component of the structure, design methods and equipment choices made elaborate. Hardware circuit by the microcontroller, display circuit, alarm circuits, detection circuit, the power circuit, railings control circuit. And gives a detailed flow chart of the design process, initialization procedures and testing procedures, control procedures. Assembly language software used to prepare.

Key words: SCM AT89S52; ultrasonic sensors; RS232; model testing

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专科生毕业设计（论文）

目 录

第1章 绪 论 .......................................................................................................... 1

1.1 关于自动检测收费的发展趋势 ............................................................... 1 1.2 本课题研究意义及内容 ........................................................................... 1 1.3 系统的经济可行性 ................................................................................... 2 第2章 系统设计方案论证 .................................................................................... 3

2.1 车辆分类方法 ........................................................................................... 3 2.2 车型检测方法选择 ................................................................................... 4 2.3 系统功能 ................................................................................................... 4 2.4 车型自动识别系统组成 ........................................................................... 5 第3章 系统硬件设计 ............................................................................................ 6

3.1 单片机选择 ............................................................................................... 6 3.2 单片机基本电路设计 ............................................................................... 9

3.2.1 时钟电路设计 ................................................................................ 9 3.2.2 复位电路设计 ................................................................................ 9 3.2.3 看门狗定时器 .............................................................................. 10 3.3 传感器选择和设计 ................................................................................. 11

3.3.1 超声波传感器 .............................................................................. 11 3.3.2 电磁传感器 .................................................................................. 17 3.4 栏杆控制器电路设计 ............................................................................. 17

3.4.1 光电隔离管与继电器简介 .......................................................... 17 3.4.2 抬杆电路接线图及工作原理 ...................................................... 18 3.5 显示电路 ................................................................................................. 19

3.5.1 LED显示器结构与原理 ............................................................... 19 3.5.2 LED显示方式 ............................................................................... 20 3.5.3 显示器与单片机连接图 .............................................................. 21 3.6 单片机与主PC机通信接口 ................................................................... 23 3.7 电源部分 ................................................................................................. 24 3.8 报警电路 ................................................................................................. 25 3.9 键盘电路 ................................................................................................. 25 第4章 系统软件设计 .......................................................................................... 27

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专科生毕业设计（论文）

4.1 系统软件设计思想 ................................................................................. 27 4.2 地址及内存分配 ..................................................................................... 27 4.3 主程序 ..................................................................................................... 28 4.4 信号采集子程序 ..................................................................................... 29 4.5 数据抗干扰算法流程图 ......................................................................... 30 4.6 单片机与主机通信程序 ......................................................................... 31 4.7 中断子程序 ............................................................................................. 32 4.8 车型识别及显示子程序 ......................................................................... 33 第5章 结 论 ........................................................................................................ 34 参考文献 ................................................................................................................ 35 致 谢 ...................................................................................................................... 36 附 录 ...................................................................................................................... 37

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