Smoke Detector System using MQ135 and STM32

The Smoke Detector System utilizing the MQ135 gas sensor and STM32 microcontroller is a robust and efficient solution for detecting hazardous smoke levels in various environments. This system is ideal for homes, offices, industrial settings, and any place where early detection of smoke can prevent fire hazards and protect lives.

Key Components

1. MQ135 Gas Sensor
   • Function: The MQ135 is a versatile gas sensor that detects various gases, including smoke, ammonia, benzene, and carbon dioxide. It is highly sensitive to smoke, making it ideal for smoke detection applications.
   • Output: The sensor provides an analog output proportional to the concentration of detected gases, which is then processed by the STM32 microcontroller.
2. STM32 Microcontroller
   • Function: The STM32 microcontroller processes the analog signals from the MQ135 sensor, converts them to digital values, and determines if the smoke levels exceed predefined safety thresholds.
   • Features: It includes multiple ADC channels, timers, and communication interfaces, making it well-suited for real-time monitoring and alert systems.
3. Buzzer/Alarm System
   • Function: When the smoke levels exceed the safety threshold, the STM32 triggers an alarm through a connected buzzer, alerting occupants to the potential danger.
   • Customization: The alarm can be customized to provide different types of alerts, such as a continuous sound for high danger or intermittent beeping for moderate smoke levels.
4. LCD Display/LED Indicators
   • Function: The system can be equipped with an LCD display or LED indicators to provide real-time feedback on the smoke levels detected by the MQ135 sensor.
   • Information Displayed: The display can show the current smoke concentration, system status, and alert messages.

System Workflow

1. Initialization
   • The STM32 microcontroller initializes the system, setting up the ADC for reading analog data from the MQ135 sensor.
2. Continuous Monitoring
   • The MQ135 continuously monitors the air quality. The analog signal is read by the STM32, which processes the data to assess smoke concentration levels.
3. Threshold Detection
   • The STM32 compares the detected smoke level with predefined thresholds. If the smoke concentration exceeds a safe level, the system triggers an alert.
4. Alert and Display
   • Upon detecting high smoke levels, the system activates the buzzer or alarm and updates the LCD or LED indicators to inform users of the detected hazard.
5. Reset and Recalibration
   • After the alarm is triggered, the system can be manually reset, or it can automatically reset when smoke levels return to safe values. Periodic recalibration of the MQ135 sensor ensures continued accuracy.

Applications

• Residential: Provides early smoke detection in homes, helping to prevent fire-related accidents.
• Commercial and Industrial: Ensures safety in work environments by detecting harmful smoke or gas levels.
• Smart Homes: Can be integrated into home automation systems for enhanced safety features.

Advantages

• High Sensitivity: The MQ135’s ability to detect a wide range of gases makes it highly effective for smoke detection.
• Reliability: The STM32 microcontroller offers precise processing, ensuring accurate detection and timely alerts.
• Customization: The system can be tailored to specific requirements, including sensitivity adjustments and integration with other safety systems.

The Smoke Detector System using MQ135 and STM32 is a reliable, customizable, and essential safety tool for early smoke detection, providing peace of mind and protection in various settings.

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