摘    要：中国作为一个人口大国，同时也是车辆拥有量较高的一个国家。在日常生活中，除了车辆的维护，交通秩序的维护也非常的重要，其中，危害交通秩序的最严重的一项当属酒后驾驶。因为酒后驾驶对交通事故的影响非常大。通过交警的识别再去通过呼气式酒精检测仪来判定是否酒驾，这种方法效率低而且误差大，并且传统的酒驾采集判定模式，存在不能每次都去监管到每位驾驶员的驾驶而且辛苦交警等情况，针对以上问题。在基于单片机MSC-51系列中AT89C51、酒精浓度传感器 MQ-3和模数转换器ADC0832芯片，本文提出了一种低成本的多点酒精浓度检测并在此基础上进行车辆闭锁的方案。

论文的主要从系统的硬件和软件两方面来叙述，其中硬件方面包括系统的硬件选型和结构，软件主要是软件的编程和仿真。

硬件部分包括主控作用的单片机，检测信号的酒精浓度传感器，A/D转换器，键盘输入，显示还有报警部分。通过MQ-3气敏传感器进行模拟量的采集，再经由A/D转换模转换；最后由液晶显示器显示驾驶酒精浓度值；车辆的闭锁电路由继电器模块构成。车辆的监护人员可以根据社会现实的需要设置合适的监测阈值，当检测到的目标的酒精浓度超过预设的阈值，且此检测值与其他两点的检测满足一定的逻辑关系时，蜂鸣器蜂鸣发出报警信号，启动相应的车辆闭锁控制电路。

系统软件主要分为5个模块：主程序模块、A/D转换子程序模块、显示子程序模块、声光报警和车辆闭锁程序模块及按键程序模块。

关键词：AT89C51；MQ-3传感器；酒精浓度检测；多点检测

Abstract：China as a country with large population, also has high car ownership.in daily life maintenanceof traffic is also very important in addition to the maintenance of vehicle.However the most serious of harming traffic order is drunk driving.Because the impact of drunk driving on traffic accidents is very large. Through the indentification of the traffic police, the breathalyzer is used to determine wether the driver is drunk.This method is inefficient and the error is large. Beside,traditional drink-driving patterns can't be supervised every time to monitor the driving of each driver and trouble the traffic police and so on.For the above problems , this paper presents a low-cost alcohol concentration detection and vehicle lockout control system program based on the single-chip MSC-51 series AT89S51, alcohol concentration sensor MQ-3 and ADC0832 chip.

The design of this paper mainly includes the design of the system hardware circuit and the design of the system software program .Hardware includes the hardware selection and structure of the system. The software is mainly about software programming and simulation.

The part of hardware includes a single chip for the main control, the alcohol concentration sensor for detecting signals, A/D converter, keyboard input and the alarm.It collects analog quantities through the mq-3 gas sensor and converts by the use of A/D conversion module.Finally, the liquid crystal display displays the driving alcohol level The vehicle's closed circuit is composed of the relay module. The guardian of the vehicle can pre-enter the preset alarm value according to the needs of the social reality.When the alcohol concentration of the detection object does not conform to the preset and this test satisfies the logical relationship with two other tests, the buzzer buzzes an alarm signal to start the corresponding vehicle latching control circuit.

System software is pided into five modules: the main program module, the alcohol concentration measurement subroutine module, display subroutine module, sound and light alarm program module and key program module.

Key words：AT89C51, MQ-3 sensor, Alcohol concentration detection；Multi-point detection