汽车防撞防盗报警器的设计
学 院 专 业 班 级 学 号 姓 名 指导教师 负责教师
自动化学院 测控技术与仪器
2012年6月
摘 要
随着人们生活水平的提高，汽车已经成为人们日常生活中的必需品，而汽车的安全性问题就成为了一项重要课题。本文设计了一款防盗防撞报警器，该报警器有两个功能：一是倒车时，自动检测车后方距障碍物的距离并实时显示，在到达危险距离时，发出声光报警功能；二是在车主离开时启动防盗功能，当有人靠近车时，会发出报警信号同时关闭点火装置，而防盗功能可以通过密码输入进行解除。
该系统以AT89S52单片机为控制核心，采用超声波传感器进行距离的检测，采用红外传感器检测是否有人接近车身，防盗功能的开启和密码通过键盘来实现，距离显示采用液晶显示LCD1602。该系统结构简单，功能完善，功耗低，使用方便，具有一定的应用价值。
关键词：超声波；红外；防撞；防盗
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汽车防撞防盗报警器的设计
Automobile anti-collision and anti-theft alarm system design
Abstract
With the increasing of people's lives, in order to meet the security needs, an anti-theft and anti-collision alarm is designed. The anti-theft and anti-collision alarm can measure the distance between the rear distance obstructions in reversing environmental, and cancancel based on; in the absence of environmental anti-theft function to avoid the theft of vehicles, and owners through the keyboard input password to unlock. The crash burglar alarm design is based on the microcontroller AT89S52 which set the distance of the car by the ultrasonic sensors and infrared sensors to detect and procedures for the control of the core, display, alarm, security and other functions. The entire design is composed of scheme comparison choice, independent functional modules. On the basis of analysis of the design task of alarm, the paper gives the overall design of the alarm, and detailed description of the alarm hardware and software design processes and functions to achieve, and finally a brief introduction to the production and commissioning of the alarm system process. Programs can achieve the design objectives and requirements, but the real-time control performance is less than ideal,which needs further improvement. Keywords:Ultrasonic wave; Infra-red; Anti-collision; Anti-theft
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目 录
1 绪论 ................................................................................................. 错误！未定义书签。
1.1 立题意义及发展趋势 ............................................................................................ 1 1.2 研究内容及目标 .................................................................................................... 2 1.3 本文主要内容 ........................................................................................................ 2 2 方案论证 ........................................................................................................................... 4
2.1 任务分析 ................................................................................................................ 4 2.2 硬件方案设计 ........................................................................................................ 4
2.2.1 防撞功能模块方案实现 ............................................................................. 4 2.2.2 防盗功能模块方案实现 ............................................................................. 5 2.3 软件设计方案 ........................................................................................................ 5 2.4 系统原理框图 ........................................................................................................ 6 3 硬件设计 ........................................................................................................................... 8
3.1 单片机最小系统的设计 ........................................................................................ 8
3.1.1 时钟电路 ................................................................................................... 10 3.1.2 复位电路 ....................................................................................................11 3.2 超声波测距模块 .................................................................................................. 12
3.2.1 超声波原理 ............................................................................................... 12 3.2.2 超声波测距模块电路 ............................................................................... 13 3.2.3 超声波测距模块的工作过程 ................................................................... 13 3.3 报警模块 .............................................................................................................. 14
3.3.1 声光报警模块工作原理 ........................................................................... 14 3.3.2 声光报警模块电路 ................................................................................... 14
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