倒车防撞系统的设计
摘要： 随着社会经济的发展和交通运输业的不断兴旺，汽车的数量在不断的增加。交通拥挤状况也日益严重，撞车事件也经常发生，造成了很多不可避免的人声伤亡和经济损失，面对这种情况，设计一种响应快、可靠性高并且比较经济的汽车防撞预警系统显得非常的重要。超声波测距法是一种最常见的距离测量方法。本文介绍的就是利用超声波测距法设计一种倒车防撞报警系统。
本文的内容是基于超声波测距的倒车防撞系统的设计，主要是利用超声波的特点和优势，将超声波测距系统和单片机结合于一体，设计出一种基于单片机的倒车防撞系统。本系统采用软硬结合的方法，具有模块化和多用化的特点。
关键字：超声波；倒车防撞；测距；单片机
Design of Reverse Collision Avoidance ystem
Abstract：With the social and economic development and transportation continues to boom, the automobile quantity climbs in the first mate. Traffic congestion condition also day by day serous, the collision event occurred repeatedly, has caused the inevitable person casualties and the economic loss, in view of this kind of situation, designed one kind to respond quickly, the reliability was high also a more economical automobile guards against hits the early warning system imperative, the ultrasonic wave range finding was the most common one distance range finder method, this article introduces is guards against using the ultrasonic wave range finding design one kind of reversing collision avoidance system.
The paper is based on the ultrasonic distance reversing collision avoidance system design, mainly using ultrasound features and advantages, ultrasound ranging system and the integration with the integration AT89S51 monolithic integrated circuit, AT89S51 monolithic integrated circuit based on the design of a reverse collision avoidance warning systems. The system used software and hardware integrated approach of modular and multi-use characteristics.
Keywords：Ultrasonic;Reverse collision; Ranging;Singlechip
目录
第1章 绪论…………………………………………………………………………………………………. 1
1.1课题设计的背景……………………………………………………………………………….. 1
1.2超声波测距的历史与大体发展现状…………………………………………………… 1
第2章设计思想及方案论证………………………………………………………………………….. 3
2.1系统总体的设计思想………………………………………………………………………… 3
2.2 模块选择…………………………………………………………………………………………. 3
2.2.1 显示模块……………………………………………………………………………….. 3
2.2.2 测距传感器模块…………………………………………………………………….. 4
2.2.3 报警模块……………………………………………………………………………….. 4
第3章 系统硬件电路设计……………………………………………………………………………. 5
3.1 超声波的介绍………………………………………………………………………………….. 5
3.1.1 超声波的特点………………………………………………………………………… 5
3.1.2 超声波的应用………………………………………………………………………… 6
3.1.3 超声波传感器………………………………………………………………………… 6
3.1.4 超声波测距原理…………………………………………………………………….. 6
3.1.5 超声波发射电路设计……………………………………………………………… 7
3.1.6 超声波接收电路设计……………………………………………………………… 8
3.1.7 HC-SR04超声波测距模块……………………………………………………….. 8
3.2 显示模块设计………………………………………………………………………………… 10
3.3 报警电路设计………………………………………………………………………………… 12
3.4 单片机控制电路设计……………………………………………………………………… 13
3.4.1 主控芯片……………………………………………………………………………… 13
3.4.2 时钟电路……………………………………………………………………………… 14
3.4.3 复位电路……………………………………………………………………………… 15
第4章 系统软件部分的设计………………………………………………………………………. 16
4.1系统的主程序设计………………………………………………………………………….. 16
4.2 系统的子程序设计…………………………………………………………………………. 18
4.2.1 中断处理程序………………………………………………………………………. 18
4.2.2 蜂鸣器分段报警程序……………………………………………………………. 18
4.3 本章小结……………………………………………………………………………………….. 20
第5章 硬件组装及调试……………………………………………………………………………… 21
5.1 硬件组装及调试…………………………………………………………………………….. 21
5.2测量结果………………………………………………………………………………………… 21
5.3 误差分析……………………………………………………………………………………….. 22
5.4本章小结………………………………………………………………………………………… 23
致 谢………………………………………………………………………………………………………… 26
参 考 文 献……………………………………………………………………………………………….. 27
附录A 程序清单…………………………………………………………………………………………. 28
单片机整体电路原理图……………………………………………………………………………….. 33
