Design And Implementation Of Wearable Air Quality Monitoring System Based On MEMS Sensors

In recent years,the burning of fossil fuels and the setting off of fireworks and firecrackers have caused serious air pollution problems,resulting in the continuous decline of air quality.No matter the country,the government or the people want to evaluate the air quality,in order to take corresponding measures to control the air quality in a reasonable range.However,the existing air quality detectors on the market have some disadvantages,such as large volume and not easy to carry.If we can combine the advantages of small size and easy wearing of wearable devices,we can monitor the air quality of the surrounding environment anytime and anywhere,so that people can know what level of air quality is at this moment in time,and remind people to stay away from the current environment as soon as possible when the air quality exceeds the standard.Therefore,the design of a wearable and real-time air quality monitoring system is of great significance to ensure people’s health.Based on the analysis and research of embedded technology and MEMS sensor technology,a wearable air quality monitoring system based on MEMS sensors is designed.The system is mainly composed of STM32 minimum system,power module,MEMS formaldehyde sensor module,MEMS TVOC sensor module,vibration motor module,Bluetooth module,display screen and Android mobile app.The modular design idea is adopted to simplify the design process and improve the portability.The system takes STM32F407ZGT6 chip as the control core and uses MEMS TVOC sensor module and MEMS formaldehyde sensor module collect TVOC concentration and formaldehyde concentration in the air respectively,and use fuzzy control algorithm to get air quality index,and divide it into different levels.At the same time,μ C / OS-Ⅲoperating system and stmwin graphical interface are used to realize multi task management and data visualization.When the air quality exceeds the set threshold,a window will pop up and a vibration will be sent out to remind the user.If the user clicks the "help" button on the screen or does not operate the screen for a long time,it indicates that the user’s health has been affected.At this time,a message will be sent to the android app through the Bluetooth module.After receiving the corresponding message,the Android mobile app will send a distress message containing location information to the emergency contact,so that the emergency contact can carry out the rescue.The experimental results show that the wearable air quality monitoring system designed in this paper can be worn on the wrist for real-time monitoring of air quality,and has the advantages of small size and high sensitivity,which has a certain application prospect and promotion value.