文档介绍：磬山学院
毕业设计
机电工程系
09测控1班
设计题目：超声测距单片机控制系统设计
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2013年5月 30日
超声测距单片机控制系统设计
摘要
随着社会经济的发展交通运输业日益兴旺，汽车的数量大幅攀升，交通事故频发，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，超声波测距法是最常见的一种距离测距方法，本文介绍的就是利用超声波测距法设计的一种倒车防撞报警系统。控制系统核心部分就是超声波测距仪和语音播报模块。
本次设计所采用的单片机是STC89c52,它的CPU是8位的，具有体积小，精度高，价格便宜的优点。超声测距模块采用的是HC-SR04,语音播报模块采用的是 ISD1820o整个电路采用模块化设计，由主程序模块，显示模块，语音播报模块，超声波测距模块，延时模块等组成。由单片机提供10us以上的TTL电平触发超声波测距模块，由单片机计算超声波从发射到接收的时间差，从而计算出距离值，根据单片机设定的报警范围决定是显示距离还是进行相应的语音播报。最后通过硬件和软件设计实现了各个模块的功能。相关部分附有硬件电路图、程序流程图。
最终结果表明，此设计能很好地完成汽车倒车预警的任务，并能正常显示距离和进行相应的语音提示，能较好地运用到实际生活当中。
关键词：超声波传感器；单片机；安全预警系统
Design of Ultrasonic Range Control System
based on Single-chip Microcomputer
Abstract
As social and economic development of the transport industry booming, the number of cars rose sharply,and frequent traffic accidents this situation, designing a fast response, high reliability and more economical vehicle collision avoidance warning system is imperative , ultrasonic ranging method is the most common form of distance ranging method. The thesis designs a reversing collision alarm system based on an ultrasonic distance measurement method. Control system consists of the ultrasonic range finder and voice broadcast module.
Micro-controller STC89C52 is used in the design , it is an 8-bit CPU, with small size, high accuracy, low price advantages. Ultrasonic Ranging Module uses HC_SR04 and voice broadcast module uses ISD1820. The entire circuit is modular in design, containing the main program module, display module, voice broadcast module, ultrasonic ranging module, the delay module and other components. The micro-controller provides more than lOus TTL level to trigger ultrasonic ranging time difference from the transmitter to the receiver is calculated by the micro-controller and then micro-controller calculates the distance value. Whether display or voice broadcast is according to alarm range set by the chip. Fin