DIY Air Quality Monitor

Materials Needed:

1. Microcontroller (e.g., Arduino Uno or Raspberry Pi)
2. Gas sensor module (e.g., MQ series sensors for detecting gases like CO, CO2, NO2, etc.)
3. Temperature and humidity sensor (e.g., DHT11 or DHT22)
4. Breadboard and jumper wires
5. LCD display (optional but recommended for real-time data display)
6. Power source (e.g., USB cable and power bank)
7. Enclosure (e.g., 3D-printed case or cardboard box)
8. Computer or smartphone for data visualization (optional)

Steps to Build:

1. Assemble the Hardware:
   • Connect the gas sensor module and temperature/humidity sensor to the microcontroller using jumper wires and a breadboard. Follow the wiring diagrams provided with the sensors.
   • If using an LCD display, connect it to the microcontroller as well.
2. Upload the Code:
   • Write or download code for the microcontroller that reads data from the sensors and displays it on the LCD screen (if using).
   • You can find sample code and libraries for interfacing with the sensors online. Arduino and Raspberry Pi communities often have plenty of resources for this.
3. Calibrate the Sensors:
   • Calibrate the gas sensor module according to the manufacturer’s instructions. This usually involves exposing the sensor to known concentrations of gases and adjusting the calibration parameters in the code.
   • The temperature and humidity sensor usually does not require calibration but ensure it is reading accurately.
4. Assemble and Test:
   • Assemble all components inside the enclosure, ensuring that the sensors are exposed to the air for accurate readings.
   • Power up the system and monitor the readings on the LCD display (if using). Ensure that the sensors are providing reasonable and accurate data.
5. Data Logging and Visualization (Optional):
   • If you want to log and visualize air quality data over time, you can connect the microcontroller to a computer or smartphone via USB or wireless communication (e.g., Wi-Fi or Bluetooth).
   • Write code to send sensor data to a computer or smartphone for storage and visualization. You can use software like Arduino IDE, Python, or dedicated data visualization platforms.
6. Calibration and Testing:
   • Once everything is assembled, perform calibration tests and compare the readings from your device with readings from professional air quality monitoring stations in your area.
   • Adjust calibration parameters as needed to improve accuracy.
7. Presentation and Analysis:
   • Present your air quality monitoring system to your classmates, teachers, or parents. Explain how it works and what you have learned about air quality monitoring.
   • Analyze the data collected by your system and draw conclusions about air quality in different environments or over time.

This project not only teaches school kids about air quality monitoring but also introduces them to basic concepts of electronics, programming, and data analysis. It encourages them to explore environmental issues and empowers them to take action to improve air quality in their communities.