论文汽车倒车测距仪的设计(定稿).doc

本文档系作者精心整理编辑，实用价值高。摘 要超声波汽车倒车探测器，种类繁多，应用广泛，目前在市场上呈现了一种各种档次并存，高低搭配的局面。因为它实用性强，技术成熟，所以发展很快。从第一代经过短短几年时间便发展到第五代，从纯电路模式到使用高速处理器；从单纯轰鸣器报警到显示器显示，语音报警。另外安装使用更加方便，精度及稳定性也有极大提高。在现实生活中的作用越来越大。因而汽车倒车测距仪设计的完成势必成为一种必然趋势。尽管新出厂的中高档甚至部分低价位的经济型轿车大都开始配置倒车雷达，但是，仍有许多中低档车型出厂时没有配置倒车雷达，而且现行中低档车型加装倒车雷达的市场需求也越来越大，于是自行安装倒车雷达就成了一项新兴的车辆装饰项目。目前,在一些经营汽车配件或装饰美容的商家内，甚至汽车经销商处都可安装倒车雷达。利用超声波测距原理，出于低成本、高精度的目的，提出了一种基于51系列单片机的超声波倒车雷达系统的设计方案。硬件部分采用51系列单片机作为控制器，主要有超声波发射电路、超声波接收电路、温度检测电路、LCD显示电路和报警电路。在分析超声波测距原理的基础上，给出了实现超声波倒车雷达系统的硬件设计电路图和软件设计流程图。该系统测量精度为1cm，测量范围为0.50-4.00m，完全能够满足汽车倒车系统的设计要求。关键词：单片机；超声波；测距；LCD显示屏；角度补偿AbstractUltrasonic automobile reverse detector has many different kinds of applications. Because it is practical strong , mature technology and so fast development. From the first generation after just a few short years time and development to the fifth generation, from pure circuit model to use high speed processors; The alarm to roar from the simple display, voice alarm plays an important role . In addition, using is a good kind of convenient installation. Precision and stability also have greatly improved. In the real life, function is more and more big. So car backing up the completion of design range finder will become an inevitable trend. However, there are still many low-standard cars out no configuration reverse radar, and the current low-standard cars back the radar market demand also more and more big. At present, in some business auto parts or decorative beauty in the business, and even car dealers place can install reverse radar.Because of modern production requirements, it was discovered that the need to achieve the production of non-contact distance measurement, and ultrasonic distance measurement is a good performance of the ranging approach is mainly used in reversing radar sites as well as some industrial field, this paper designed a to AT89C52 MCU as the core of the low-cost, high-precision, LCD display of ultrasonic range finder, and use some commonly used devices such as: 74HC04, etc.System consists of microcontroller, ultrasonic transmitter and ultrasonic receiver amplifier circuit and display circuit. Chip AT89C52 control calculation by the ultrasonic transmission from transmit to receive time and hence the distance to be under test. The system has easy to detect, the software fully functional, reliable, high accuracy advantages.This paper discusses the successful development of microcomputer technology, the basic principles of ultrasonic range finder, measurement method of calculating implementations. Use of software calibration, improved accuracy and machine reliability. The actual use of that greatly improves safety, reliability and accuracy. Keywords：MCU；distance meter；sensor；microcontroller；LCD本文档系作者精心整理编辑，如有需要，可查看作者文库其他文档。目 录摘 要IAbstractII1 绪 论11.1 引言11.2 研究背景及意义11.3 国内外研究现状21.4 本文研究内容32 系统总体设计42.1 超声波概述42.1.1 超声波的基本概念42.1.2 超声波的物理性质42.1.3 超声波对声场产生的作用42.2 超声波测距系统设计原理概述52.2.1 超声波传感器52.2.2 超声波测距的方案52.2.3 方案设计与论证62.2.4 控制器的选择62.2.5 测距传感器选择72.2.6 显示子系统设计72.2.7 声音报警设计82.3 系统总体结构83 系统硬件设计93.1 超声波发射和接收电路的设计93.1.1 超声波发射电路93.1.2 超声波接收电路103.2 单片机主机系统电路113.2.1 复位电路113.2.2 时钟电路113.2.3 按键电路123.2.4 蜂鸣器电路123.2.5 温度测量电路133.2.6 LCD显示电路143.2.7 电源电路154 系统软件设计164.1 系统软件设计164.2 系统主程序164.3 40KHz超声波发送子程序174.4 DS18B20温度采集程序184.5 距离计算子程序184.6 数据转换子程序194.7 LCD显示子程序205 基于Proteus的软件仿真216 PCB设计236.1 元件选择236.2 Altium Designer原理图的绘制236.3 元件封装的建立236.4 PCB的电磁兼容设计236.5 布局布线257 试验误差分析287.1 误差分析287.2 技术改进28参考文献29结束语30致 谢31附 录32部分样图精彩预览成品布线图 覆铜后的PCB 样机安装图 3D效果图如需购买全套完整论文资料，请去如下两个网址均可购买：/item.htm?spm=686.1000925.1000774.13.aYWBgpidttp://item.htm?spm=686.1000925.1000774.19.aYWBgpid论文100%本人写作，包括基于单片机的protues+keil软件的联合仿真源文件、源电路图、设计论文、开题报告、毕业答辩的PPT报告及相关文件的截图，涵盖所有毕业论文的相关文件1.1 本论文100%本人写作，包括基于单片机的protues+keil软件的联合仿真源文件、源电路图、设计论文、开题报告、毕业答辩的PPT报告及相关文件的截图，涵盖