In recent years, with the popularity of cars in China, the safety of cars has attracted our attention. According to the latest data, drunk driving has become the main cause of frequent traffic accidents. The number of deaths caused by drunk driving in China has increased at an average rate of 7.3% every year. Drinking driving can cause harm to others and others, and it can lead to vehicle destruction and death. In order to prevent drunk driving, it is necessary to design an intelligent circuit to detect the alcohol content in the driver’s body and cut off the power supply of the car in time.
In this design, MQ-3 alcohol sensor is used to measure the alcohol concentration in the driver’s body after drinking, and the signal is transmitted to the microcontroller. Finally, the microcontroller displays the alcohol concentration by processing the digital signal. When the threshold value is exceeded, an audible and visual alarm is given, and the vehicle power is cut off through the control relay. In terms of software, the functions of each subprogram are relatively independent, which is convenient for debugging and modification. When the alcohol concentration in the driver’s body exceeds the standard, the system can automatically cut off the power supply of the car starting system, give an audible and visual alarm, and display the alcohol concentration in real time through the digital tube.
Key words :Single chip microcomputer; Alcohol sensor; Human body heat release; Drunk driving;