汽车倒车测距仪word版

密级：公开

汽车倒车测距仪的研究Design for the Car Parking Sensor 学院：信息科学与工程学院

专业班级：电子信息工程XXXX班

学号：XXXX

学生姓名：XXX

指导教师：XXX （副教授）

2012 年 6 月

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摘要

随着社会经济的发展，交通运输业日益兴旺，汽车的数量在大幅攀升，交通拥挤状况也日趋严重，撞车事件屡屡发生，造成了不可避免的人身伤亡和经济损失，针对这种情况，设计一种响应快，可靠性高且较为经济的汽车防撞预警系统势在必行。

本文介绍了一种基于80C51单片机控制的汽车倒车测距仪。采用超声波测距技术与单片机技术相结合，利用超声波传输中距离和时间的关系运算，80C51单片机计算出车后的障碍物与汽车尾部的距离，并通过数码显示车后的障碍物与汽车尾部的距离远近，实时发出报警信号，使驾驶员能时刻了解倒车时车后的环境并采取积极有效措施，从而大大提高了驾驶的安全性。

文章对总体设计思想进行了论述，分析了系统主要功能并以系统硬件设计框图的形式体现，进行了方案选择与方案论证。完成了硬件电路的设计，描述了各模块电路的组成，其中包括超声波发射电路、超声波接收电路、显示电路、蜂鸣器报警电路等，分析了电路中所用芯片的主要功能及各部分电路的工作原理。

本设计通过对各模块的硬件和软件的设计，基本能够达到设计要求，满足汽车倒车安全指标。

关键词：超声波；单片机；测距

Abstract

With the development of social economy, transportation industry is booming. The number of cars climbed sharply, traffic congestion has become more and more serious. Crash ongoing caused the inevitable personal casualty and economic loss. In this kind of situation, design a kind of fast response, high reliability and more economical car crash warning system is imperative.

This paper introduces a kind of Car Parking Sensor based on 80C51 single chip microcomputer. Using ultrasonic transmission distance and time relationship operations, along with the ultrasonic ranging technology and single chip microcomputer combined, 80C51 single chip computer calculate the distance between the obstacles and the rear of the car, showing the distance with Digital tube and sending real-time warning signal. This made the driver can always know the environment reverse of the car and take positive and effective measures, which greatly improve the driving safety.

It discusses the overall design thought, analyses the main function and show the hardware design of the system with a diagram, and give the plan selection and scheme comparison. Completed the design of the hardware circuit, described the module of the circuit component, which include the ultrasonic transmitter circuit, ultrasonic receiver circuit, display circuit, the buzzer warning circuit. Analysis of the main function of the chip used in the circuit and the works for various parts of the circuit.

Through the design for the software and hardware of each module, it can basically meet the design requirements and the reversing safety indicators.

Keywords: ultrasonic; single chip microcomputer; ranging

目录

摘要 ....................................................................................................................... I Abstract ......................................................................................................................... I I 第1章绪论 .. (1)

1.1 课题研究的意义和背景 (1)

1.2 国内外发展现状 (1)

1.3 研究内容及论文构成 (2)

第2章设计思想及方案论证 (4)

2.1 方案选择 (4)

2.1.1 测距传感器模块 (4)

2.1.2 显示模块 (5)

2.1.3 报警模块 (5)

2.2 系统总体设计思想 (5)

2.3 本章小结 (6)

第3章硬件电路设计 (7)

3.1 超声波发射及接收电路设计 (7)

3.1.1 超声波的介绍 (7)

3.1.2 超声波的特点 (7)

3.1.3 超声波的应用 (7)

3.1.4 超声波传感器 (8)

3.1.5 超声波测距原理 (8)

3.1.6 超声波发射电路设计 (10)

3.1.7 超声波接收电路设计 (10)

3.1.8 HC-SR04超声波测距模块 (11)

3.2 显示模块设计 (14)

3.3 报警电路设计 (15)

3.4 单片机控制电路设计 (16)

3.4.1 主控芯片STC12C56 (16)

3.4.2 时钟电路 (17)

3.4.3 复位电路 (18)

3.5 本章小结 (19)

第4章系统的软件设计 (20)