【毕业论文】基于单片机的酒精探测仪设计.doc

基于单片机的酒精探测仪设计 摘 要 机动车驾驶人员“酒后驾车”极易发生道路交通事故，严重危害了道路交通安全和人民生命财产安全。人饮酒后，酒精通过消化系统被人体吸收，经过血液循环，约有90%的酒精通过肺部呼气排出, 因此测量呼气中的酒精含量，就可判断其醉酒程度。 本探测仪采用酒精气体敏感元件作为探头，由一块集成电路对信号进行放大，并驱动十个发光二极管按信号电压高低依次显示，同时由单片机控制对信号进行模数转换用数码管输出。对刚饮过酒的人，只要向探头吹一口气，探测仪就能显示出酒精气体的浓度高低。若把探头靠近酒瓶口， 它也能轻而易举地识别出瓶内盛的是白酒还是黄酒，能区分出酒精含量的高低。 关键词：传感器；酒精探测仪；单片机；模-数转换 Abstract Driver drives very easy to happen traffic accident after drinking which endanger traffic safety and people safety of life and property seriously. After people drink, the alcohol is absorbed by the human body through the digestive system, through the blood circulation, nearly it have discharge exhaling lung alcohol of 90%. So measure the content of alcohol while exhaling , can judge its drunk degree. This detector adopts the alcohol gas sensitive element conduct to pop ones head , is amplified the signal by an integrated circuit, urge ten LED show sequentially according to signal voltage high or low prices, the Micro Controller Unit controls and changes and exports to the signal with the digital tube moduluses at the same time. To person that drink just, so long as to pop ones head one breath of blowing, detector can demonstrate density high or low prices , alcohol of gas. If pop ones head close to wine bottleneck, it can recognise whom the bottle hold white spirit or yellow rice or millet wine easy too, can distinguish out the level of the content of alcohol . Keywords: Sensor Alcohol detector Micro Controller Unit Analog to Digital Convert 目 录 摘 要 I Abstract II 第1章 绪论 1 第2章 传感器基础知识 3 2.1 传感器的定义 3 2.2 传感器的分类 3 2.3 传感器的特性 4 2.4 传感器的选择 5 2.5 传感器的发展方向 6 第3章 方案论证 8 3.1 气体传感器的选择 8 3.1.1 MQ-3基本介绍 8 3.1.2 MQ-3的检测 9 3.2 编程语言的选择 10 3.3 开发工具 11 3.3.1 单片机选择 11 3.3.2 开发环境 13 3.3.3 仿真器 13 3.4 系统框图 14 第4章 系统实现 15 4.1 发光二极管显示 15 4.1.1 LM3914基本介绍 15 4.1.2 工作原理 16 4.2 数码管显示 16 4.2.1 ADC0809主要特性 16 4.2.2 ADC0809内部结构 17 4.2.3 ADC0809外部特性 17 4.2.4 工作原理 19 4.2.5 A/D转换 20 4.2.6 显示部分 21 第5章 结论 22 5.1 结果分析 22 5.2 有待改进