1、 题 目 酒精浓度探测仪 毕业设计毕业设计( (论文论文) )说明书说明书 摘摘 要要 本设计实现了对不同浓度酒精的检测和显示，通过适当改进可以用于检测酒后驾车。本文用 STC12C5A16AD 单片机与 MQ-3 型气体传感器实现了对酒精浓度的测量，并对测量数据进行显示。 本设计主要研究了（1）硬件方面，MQ-3 气体传感器技术参数的检测和将它接入到酒精浓度检测模 块中；将采集到的模拟电压信号通过单片机控制经 A/D 转换，得到数字电压信号；用于显示浓度的数码 管显示模块。 （2）软件方面，主要研究了电压到浓度的线性转换和最终浓度值的数码管显示。 （3）对设 计的传感器进行了标定。设计的传感
2、器对酒精气体反应灵敏，能在有效范围内测量它的浓度值。并且在 检测低浓度酒精时误差较小，最大误差为 8.2%满足设计要求。 本设计的特色在于标准的确定。对于流动空气，样品的稳定性和水蒸气的影响，提出了解决方案和 验证方法。对不同的区间浓度和电压转换关系做线性化处理，简化了硬件电路的设计。设计的传感器可 以检测不同浓度的酒精气体，改进之后对解决酒后驾车事故和特殊场合酒精检测都可以使用。 关键词关键词：气体传感器;模数转换;单片机 AbstractAbstract Different concentrations of alcohol solution are detected and showed
3、 in the design. The design can be used to the detection of drunk driving through improvement. In this thesis, the concentration of alcohol can be measured and displayed by using the gas sensor based on STC12C5A16AD MCU and MQ-3. In the thesis Major researches are three points. (1) In the hardware, d
4、etecting the technology parameters MQ-3 gas sensor, and connecting it to a testing part of the alcohol gas concentration; Analog voltage signal amplification to drive light-emitting diode light to alarm; conversing the voltage signal through the A/D conversion at the control of the single-chip, obta
5、ining the digital voltage signal; displaying the concentration in the digital tube display module.(2)In the Software, linear conversion between the concentration of the alcohol and the voltage and the digital display of the final concentration value.(3) The designed sensor is calibrated. The design
6、of gas sensor is responsive to the alcohol, can measure concentration in the effective range of its concentration. And in the low concentration of alcohol in the test the error is small with the maximum error 8.2%, meeting requirements of the design. The characteristics of the thesis are to determine the standard. The solutions and verification methods are proposed about the flow of air samples, the sample stability and water vapor. The conversion between voltage and concentration in di
