AIR QUALITY MONITOR AND ALERT SYSTEM

This is a easy Arduino project that you could create to impress your lecturer and friends. DIY arduino nano air quality monitor which can measure surrounding air quality also shows temperature and humidity in your room.

ABOUT THIS PROJECT

Many times we feel very week while waking up from the bed even after getting a good sleep at night. This sometimes happens because of the poop air quality in the closed room at night.

This is a low cost air quality monitor which can monitor the air quality of room using MQ135 air quality sensor. It also measure the room temperature and humidity using DHT11 and shows the data on a OLED display. It is a fun little project and very helpful too.

What is an air quality monitor?

The Air Quality monitor is a facility to measure air quality using sensors, processing using microcontrollers and showing results using various displays.

What sensor can detact air quality?

Nowdays, progress in electronics parts and avaibility of various sensor like MQ-135, MQ-2, MQ-3, MQ-4, MQ-5, MQ-6 to measure the air quality, different systems are developed to monitor the number of air quality in the air. MQ-135 is one of the most popular sensors.

HARDWARE COMPONENTS

Arduino

MQ-135 Air Quality Sensor

DHT11 Temperature & humadity Sensor

Buzzer

POWER/CONNECTIONS

Wires

USB

APPS AND ONLINE SERVICES

Arduino IDE

Before we began this project, We went through a planning process to choose what to undertake. We couldn't locate anything on air quality monitor and alert system, and wanted to make something original that had never been done before. We thus had immediate confirmation of our proposal concept. Background information on the most significant and complex components is provided in this section.

ARDUINO :

- Open-source electronics platform Arduino makes use of straightforward hardware and software to make it simple to use. Arduino boards may transform inputs, such light from a sensor, a user pressing a button, or a tweet, into outputs, like turning on an LED, starting a motor, or posting something online. The format code of C++ is used by the Arduino.

DHT11 :

- The DHT11 is a basic, ultra low-cost digital temperature and humidity sensor. It uses a capacitive humidity sensor and a thermistor to measure the surrounding air and spits out a digital signal on the data pin (no analog input pins needed).

MQ-135 :

- The MQ-135 Gas sensor can detect gases like Ammonia (NH3), sulfur (S), Benzene (C6H6), CO2, and other harmful gases and smoke. Similar to other MQ series gas sensor, this sensor also has a digital and analog output pin.

BUZZER :

- A buzzer or beeper is an audio signaling device, which may be mechanical, electromechanical, or piezoelectric. Typical uses of buzzers and beepers include alarm devices, timers, train and confirmation of user input such as a mouse click or keystroke.

Insert nodemcu ESP8266 to the breadboard.

Temperature Connect the Temperature sensor to pins on nodemcu ESP8266.

1. Connect a jumper wire from + to Arduino 3V

2. Connect a jumper wire from out(e, 27) to Arduino D4

3. Connect a jumper wire from - to Arduino GND

Smoke Sensor (MQ-135)

Connect the Smoke Sensor (MQ-135) sensor to pins on nodemcu ESP8266.

1. connect the MQ135 Analog input pin to A0 of NodeMCU

2. connect its VCC and GND to NodeMCU Vin

3. GND respectively.

Buzzer.

1. Connect the passive to D2

2. Connect the active to GND

In the coding part you will need to install library to run the code

DHT.h

There is main function in the code air_sensor(). In air_sensor() function it read the analog value from the Air quality sensor gasLevel = analogRead(sensor); and define the quality for that corresponding gasLevel.

In the air_sensor() function you might need to celebrate your gas Level value for your sensor. For that power 5V to the mq135 sensor and put it on a clean environment for at least 24 hour before using it. it is (burning) necessary for this kind of sensor because the sensor comes polluted. S o burning helps it to clean itself and gives more accurate result. Then connect the sensor to your circuit and go outside with it and tune the right value for your place.

When all of the wiring and code is finished, it's time for the final assembly. I used a small cardbord to put air quality monitor and alert system arduiono. If you don't have the materials, don't worry; you can make a box out of whatever you have lying around.

1. Download thinger.io App and Create Account.

2. Name Peoject

- " Name "

- " ESP8266 "

- " WiFi "

3. Add Widget

* Temperature

- New Gauge

- Name = " Temperature "

- Input = " V0 "

- Min = " -40 " Max " 85 "

- Label = " C "

* Humidity

- New Gauge

- Name = " Humidity "

- Input = " V1 "

- Min = " 0 " Max " 100 "

- Label = " % "

If you followed the steps correctly, you should have a fully functional air quality monitor and alert system. If not, go over the steps again to see where you went wrong.