Introduction: SmartAir

About: Student MCT at Howest (Kortrijk Belgium)

Hi, I am a student Multimedia & Communication Technology at Howest. To show what I learned this year I made a Smart Air Purifier. I made this project because a lot of people have bad in house air quality. Bad air quality can cause headaches, sneezing, couching and many more health issues. 'SmartAir' wil help you become aware of this problem and even help you to improve in house air quality.

SmartAir measures:

  • General gas concentrations in ppm
  • Humidity in %
  • Temperature in °C
  • Fine dust in µg/m³

The air quality will be represented by a RGB LED-strip. To view the data you can look on the website. The website also shows an overall score and controls to manually control the LED-strip. To finish it off there is a LCD display that shows the IP address of the site.


This project cost around €150.

  • Raspberry pi 4 model B
  • Temperature and Humidity sensor DHT11
  • Gas sensor MQ-135
  • Dust sensor GP2Y1010AU0F
  • MCP3008
  • 12V 120mm fan
  • 12V power adapter
  • Female power adapter plug
  • RGB LED-strip WS2081
  • HEPA Air filter
  • IRF830PBF transistor
  • L7805CV voltage regulator
  • HD44780 LCD Display
  • Your favorite wood
  • Glue
  • Nails

Step 1: Fritzing Schema

I used a 12v extern power supply for the fan. With a voltage regulator I brought the voltage down to 5V for the other components.

Step 2: Database

I hosted this database on my Raspberry pi using MariaDB.

There is a total of 5 tables. the sensors, the actuators, the history and a table used for the tip section.

Step 3: Setup

I used a breadbord to make my circuit. You could solder everything together if you want to but for various reasons I decided not to. The code I made can be found on my Github.

Step 4: Website

To display the data I made a clean website with lots of whitespace. The site also gives you the opportunity to control the fan and RGB LED-strip.

Step 5: Case

The case is entirely made of wood. For the connection between the filter and the fan I 3D printed a mounting piece.