基于AT89S51单片机的超声波测距系统.doc

摘要 随着生活质量的提高，工作的需要，科技的发展，人们将越来越多的在生活中和工作中将汽车作为其日常的交通工具。给汽车安装了倒车雷达系统，将使汽车安全性大大提高，以确保行车安全。 本系统是基于单片机控制的汽车倒车“雷达”系统，主要实现驾驶员在无后视的情况下能通过系统的数字显示，清楚车后障碍物的状况，并通过报警信号避免撞车，在本系统的协助下安全的完成倒车。 本文主要内容如下： 1.系统的阐述倒车雷达的可行性和实现方法。 2. 阐述了倒车“雷达”系统的系统组成。 3.详细介绍其硬件电路构成，软件设计和功能实现过程。 4.说明硬件电路和软件电路的调试过程。 关键字：单片机;汽车；超声波；测距 Abstract In the condition of the life quality raise, necessaries of work, development of science and technology, more and more people will use automobile as their important tool in the living life and neutralization work .To fix a back car radar system in the motor vehicle will make cars backward more secure. And will improve the security of driver. This radar system is based on one-chip computer to control a automobile and to help a driver to backed a car . Below the situation that the main driver cant see the afterwards of car, by means of the systematic LED digital display, the driver can see the distance between the car to the obstacle state. Moreover, it can avoid the collision of vehicles by the means of the alarm averts. And make backed a car secure complete by the systematic help. The original chiefly act as the below substance: 1. The systematic elaborates backing car radar feasible quality and the realization means. 2. Elaborating what the systematic system is marked up. 3. Detailedly introducing such hardware electric circuit constitutes, software design and the process that how to really process. software design and the process that how to really process. 4. Directions hardware electric circuit and software debug process. Key words: MCU; Automobile; Ultrasonic ; Distance- measurement 目 录 Abstract 1 第1章 绪论 3 1.1 课题背景，目的和意义 1.2国内外研究现状简述 1.3超声波测距的应用 1.4于单片机的超声波测距系统 3 1.5题主要内容 4 第2章 超声波测距原理概述 5 2.1超声波传感器 6 2.1.1 超声波发生器 6 2.1.2 压电式超声波发生器原理 6 2.2单片机超声波测距系统构成 2.3超声波测距的原理 第3章 设计方案 3.1方案选择的论证和选择 3.2 AT89S51单片机 8 3.3 超声波测距系统构成 11 3.3.1 超声波