基于单片机的倒车雷达设计 毕业论文 摘要&目录

摘要

本文的研究内容是基于STCC52单片机超声波测距系统的设计，利用超声波的特点和优势，将超声波测距电路和STCC52单片机结合于一体。本系统设计包括硬件电路设计以及软件设计，硬件电路设计主要有单片机系统电路、超声波发射电路、超声波检测电路和显示电路。软件设计包括主程序、超声波发射子程序、超声波接收中断程序和显示子程序的设计。

当人们驾驶汽车倒车时，由后部超声波发射器发射出超声波，遇到障碍物反射回来，通过超声波接收装置接收，然后通过单片机计算发射和接收的时间差进而计算出距离，并与安全距离值对比，当小于安全距离时，单片机输出高电平报警电路开始报警，通过显示器实时显示距离。

本设计采用C语言编程，实现了硬件电路的运行测试，达到了系统设计目标。经过进一步完善功能后，将对驾驶员日常驾驶提供较大的帮助。

关键词：单片机；超声波；测距

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沈阳理工大学学士学位论文

Abstract

The contents of this article ultrasonic ranging system based STCC52 microcontroller design, features and advantages of the use of ultrasound Ultrasonic Ranging circuits and STCC52 of microcomputer with in one. The system design includes a hardware circuit design and software design, hardware circuit design, microcontroller system circuit, ultrasonic transmitter circuit, ultrasonic detection circuit and display circuit. The software design includes the main design, ultrasonic emission subroutine design, ultrasonic receiver to interrupt the program and display routines.

When people drive a car reversing from the rear ultrasonic transmitter emits ultrasound, an obstacle reflected by the ultrasonic receiver receives, and then by the microcontroller to calculate the transmit and receive time difference and then calculate the distance, and compared with the safe distance values when less than a safe distance from the microcontroller output high alarm circuit alarm, display real-time display distance.

This design uses the C programming language, and run tests of the hardware circuit to achieve the system design goals. After further improve the function, driver's daily driving will provide more help.

Keywords:SingleChipMicrocomputer；Ultrasonic；Ranging

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沈阳理工大学学士学位论文

目录

1绪论 ......................................................................................................................................... 1 1.1课题背景 ........................................................................................................................... 1 1.2国内外研究现状 ............................................................................................................... 1 1.3课题研究内容 ................................................................................................................... 2 2 超声波测距原理 .................................................................................................................. 4 2.1 超声波传感器介绍 .......................................................................................................... 4 2.2超声波传感器的特性 ....................................................................................................... 5 2.3超声波测距的原理以及实现 ........................................................................................... 6 3 系统硬件设计 ........................................................................................................................ 8 3.1系统总体结构设计 ........................................................................................................ 8 3.2单片机最小系统 ............................................................................................................... 8 3.2.1单片机的选择 ............................................................................................................ 8 3.2.2STCC52简介 .......................................................................................................... 9 3.3超声波测距电路 ............................................................................................................. 10 3.4 显示器LCD1602 ......................................................................................................... 12 3.4.1液晶显示器的优点 .................................................................................................. 12 3.4.2液晶显示器的原理 .................................................................................................. 13 3.4.3LCD1602主要参数以及引脚功能 .......................................................................... 15 3.5 数字温度计DS18B20 .................................................................................................. 16 4系统软件设计 ....................................................................................................................... 18 4.1超声波测距时序 ............................................................................................................. 18 4.2主程序设计 ..................................................................................................................... 18 4.3超声波发射子程序设计 ................................................................................................. 21 4.4超声波接收中断程序设计 ............................................................................................. 22 4.5显示子程序设计 ............................................................................................................. 25 5 系统调试分析 .................................................................................................................... 28 5.1 硬件电路连接 ................................................................................................................ 28

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沈阳理工大学学士学位论文

5.2系统实物调试 ................................................................................................................. 28 5.3误差产生原因分析 ......................................................................................................... 31 5.3.1温度对超声波声速的影响 ...................................................................................... 31 5.3.2回波检测对时间测量的影响 .................................................................................. 31 5.3.3超声波传感器所加脉冲电压对测量范围和精度的影响 ...................................... 32 5.4针对误差产生原因的系统改进方案 ............................................................................. 32 结论 .......................................................................................................................................... 34 致谢 .......................................................................................................................................... 35 参考文献 .................................................................................................................................. 36 附录A 英文文献 .................................................................................................................. 37 附录B 中文文献 .................................................................................................................. 41 附录C 系统硬件电路原理图 .............................................................................................. 45 附录D超声波测距雷达设计PCB图 .................................................................................... 46 附录E程序源代码 .................................................................................................................. 47

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沈阳理工大学学士学位论文

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