University: Daffodil International University
Department: Computer Science and Engineering
Course: Embedded Systems and IoT Project
This project is an IoT-enabled safety system designed to detect gas leakage (LPG, Methane, Smoke) in residential and industrial environments using the ESP32 DevKit V1. The system utilizes three MQ2 gas sensors placed at different heights (ceiling, stove level, ventilation outlet) to ensure accurate detection. Upon detecting gas levels above calibrated thresholds, the system triggers a local alarm (Buzzer + Red LED), automatically activates an exhaust fan via a relay, and sends real-time alerts (Push Notifications + Email) to a smartphone via the Blynk IoT Platform.
- Multi-Point Detection: Uses 3 calibrated MQ2 sensors for different zones (Source, Ceiling, Vent).
- Automatic Ventilation: Active mitigation system that turns on an exhaust fan immediately when a leak is detected.
- IoT Connectivity: Real-time monitoring dashboard and remote alerts using the Blynk Mobile App.
- Dual Alert System: * Local: LCD Display (16x2 I2C), Buzzer, and Status LEDs.
- Remote: Push notifications and automated emails.
- Microcontroller: ESP32 DevKit V1
- Sensors: 3x MQ2 Gas Sensors
- Actuators:
- Relay Module (SPD-05VDC-SLC)
- DC Ventilation Fan (12V)
- Piezo Buzzer
- Display: 16x2 LCD with I2C Interface
- Indicators: Red & Green LEDs
| Component | ESP32 GPIO Pin | Description |
|---|---|---|
| MQ2 Sensor 1 | GPIO 39 (VN) | Ceiling Level (Threshold: 1400) |
| MQ2 Sensor 2 | GPIO 36 (VP) | Stove Height (Threshold: 350) |
| MQ2 Sensor 3 | GPIO 34 | Vent Outlet (Threshold: 1600) |
| Relay (Fan) | GPIO 18 | Active LOW trigger |
| Buzzer | GPIO 4 | Alarm Output |
| Green LED | GPIO 15 | Safe Status Indicator |
| Red LED | GPIO 2 | Danger Status Indicator |
| I2C LCD | GPIO 21 (SDA), GPIO 22 (SCL) | System Display |
- Monitoring: The ESP32 continuously reads analog values from all three sensors.
- Analysis: The system compares readings against custom thresholds calibrated for each sensor's location:
- Sensor 1 (Ceiling): > 1400
- Sensor 2 (Source/Stove): > 350
- Sensor 3 (Vent): > 1600
- Trigger: If any sensor exceeds its threshold:
- Visual/Audio: Red LED and Buzzer turn ON.
- Action: Relay switches LOW to activate the Exhaust Fan.
- IoT: Blynk sends a "Gas Leak Detected" notification and Email.
- Display: LCD updates to show "Warning: Gas Detected".
- Safety: Once levels return to normal, the system resets to Green LED and "All Normal" status.
Figure: Real implementation of the monitoring unit.
Figure: Mobile dashboard showing real-time PPM levels and fan status.
- Showrav Das (ID: 221-15-5425)
- Adnan Rahman Sayeem (ID: 221-15-5505)
- Niloy Biswas (ID: 221-15-5894)
- Shahnewaz Saeem (ID: 221-15-5442)
- Pronob Chandra Sarkar (ID: 221-15-4840)
Supervised By: Indrojit Sarkar
Lecturer, Department of CSE
Daffodil International University
Created: August 2025