Gas detection system with real-time monitoring and Buzzer alarm

The EzloPi smart devices provide automation through simple, customizable use with our open-source EzloPi platform, making daily life easier and improving human-machine interactions.

Before moving into this example, it is very important to know about the device registration, provisioning and converting the ESP32 device into an EzloPi device along with knowledge of Web Flasher, MiOS Mobile Application for Android/iOS and the MiOS Web Application.

The following example demonstrates how the MQ9 combustible gas sensor and buzzer is interfaced with the EzloPi device. The MQ9 combustible gas sensor is a gas detection module for combustible gasses widely used in electronic projects and home automation systems. It is highly sensitive to various gasses like LPG (liquefied petroleum gas), propane, methane, and other flammable gasses. We can set the threshold values for gas concentration levels that trigger alerts or actions.

By interfacing the MQ9 flammable gas sensor and buzzer with the EzloPi device, you can create a smart gas detection and alert system that helps protect and alert the users against the dangers of gas leaks in various environments, from homes and offices to industrial facilities.

Welcome to the project demonstration video section. The following video showcases the key aspects of Integrate Buzzer with MQ9 gas sensor triggered when gas detected using EzloPi Platform, providing a visual walkthrough of its implementation.

The following components are required for interfacing with the EzloPi device:

• ESP32 as an EzloPi smart device.
• MQ9 LPG Combustible Gas Sensor.
• Buzzer.

The wiring diagram for the ESP32 30 pin is represented as below:

The following connections are made in order to complete the circuit setup:

From ESP32 to the MQ9 Combustible Gas Sensor:

From ESP32 to the Buzzer:

Set up your device/hardware by visiting config.ezlopi.com

2. Log in using the credentials which you just set earlier while signing up.

3. Now, click on the Connect Device button and a pop-up window will appear.

4. Now, select COM Port to which your ESP32 device is connected. In our case, the COM3 port is used.

Click Connect.

5. If you are new to this and it's your first time configuring, select Create new Device ID. Enter Wifi SSID and Wifi Password.
6. In the Device Configuration, tab click on Other.

7. A window will open for inputting the following parameters:

• Set a device name of your choosing. In our case, we set it to MQ9 Gas Sensor.
• Set Device subtype to MQ9 LPG Flammable Gas Sensor.
• Check the box of GPIO 1.
• Set GPIO 1 to 25.
• Check the box of GPIO 2.
• Set GPIO 2 to 33.
• Then Click Apply Button.

8. Again in the Device Configuration, tab click on Digital Output.

9. A Digital Output window will open for inputting the following parameters:

• Set a device name of your choosing. In our case, we set it to Buzzer.
• Set Device subtype to LED.
• Set OUT GPIO to 15.
• Set Resistor to PULL UP.
• Set the default value to LOW.
• Then Click Apply Button.
• After clicking the apply button you can see a table of your setting in the device configuration tab.
• Press the Flash Device button.

12. A window will appear on the bottom right side of the screen displaying “Please press BOOT button while flashing begins.”

13. Hold the BOOT button down until the next window appears on the bottom right side of the screen which says “Installation prepared. Please release the boot button now.”

14. Release the BOOT button from your ESP32 when this pop-up on the bottom right window appears.

15. After some time, a popup will appear saying Device Flashed Successfully! This means that your device has been set up successfully.

1. After configuring the controller with the EzloPi web flasher, head to ezlogic.mios.com

2. Use the same credential to log in that you used for configuring the controller with the web flasher.

3. Here, on the MiOS web dashboard, you will be able to see the tiles for the MQ9 gas sensor and buzzer. These tiles will indicate the status of the Buzzer depending on the gas concentration levels being detected by the sensor.

MeshBots:

4. On the right side of the screen under Automation, click on MeshBots.

5. On meshbot screen, click on Create new MeshBot button present on the top right corner of the screen.

6. After clicking on Create new MeshBot you will see this now under Automation MeshBot click on Cloud.

7. On the next screen you will see that we can create a name of our choosing, in this case we write it as Test001.

8. In the trigger tab you can set the TRIGGER for your device and in the ACTION tab you can set the action to be performed based on the trigger which you have created.

9. Set these values in TRIGGER section:

• Set Node Type to Device.
• Set the Node to MQ9 Gas Sensor.
• Set the Capability to Gas alarm.
• Set the value to combustible_gas_detected.

10. Set these values in the ACTION section.

• Click on the TRUE part of the Add Action section..
• Set Node Type to Device.
• Set Controllable Type to Buzzer.
• Set the Capability Type to switch.
• Set the Value to true.
• Set Action to immediately.

11. Set these values in the ACTION section.

• Click on the False part of the Add Action section..
• Set Node Type to Device.
• Set Controllable Type to Buzzer.
• Set the Capability Type to switch.
• Set the Value to false.
• Set Action immediately.
• Now Click the Save button.

12. After clicking the save button you can see this screen on the top right corner of the screen.

13. Here you can see your saved MeshBot. Now click on Dashboard.

14. Now, on the MiOS web dashboard, you will be able to see the tiles for the MQ9 gas sensor and buzzer. In this condition you can see that when a certain concentration level of gas is detected by the gas sensor then our buzzer gets triggered because of the rules we have set in the meshbot.

You can download the MIOS Android app from the Google Play Store and Apple App Store.

1. After downloading the app, proceed to install the application and open it.

2. Using the MIOS mobile application, create a new Ezlo Cloud account using the sign-up option. If you already have an account, you may proceed to log in.

3. After successfully logging in, you will be able to see the number of controllers connected such as a lamp, fan, or any other device in the MiOS app. Tap on any controller of your desired ID:

4. You will be able to see the status of your controller whether it is online or offline. Access the device dashboard, and tap the device. The following view of the dashboard will appear:

5. On the MiOS mobile dashboard, you will be able to see the tiles for the MQ9 gas sensor and buzzer. These tiles will indicate the status of the Buzzer depending on the gas concentration levels being detected by the sensor.

6. In the above condition, you can see that when a certain concentration level of gas is detected by the gas sensor then our buzzer gets triggered because of the rules we have set in the meshbot.