Hazardous Gas Detection and Environmental Monitoring in Coal Mines Using IoT and GSM-Based Autonomous Robot

Coal mining environments pose significant risks due to the presence of hazardous gases, extreme temperatures, and potential fire hazards. To enhance safety and real-time monitoring, this paper presents an IoT and GSM-based autonomous robot equipped with multi-sensor integration for hazardous gas detection and environmental surveillance in coal mines. The system employs an MQ-2 gas sensor for detecting combustible gases (e.g., methane, LPG), a DHT11 sensor for temperature and humidity monitoring, and a flame sensor for fire detection. Autonomous navigation is achieved using BO motors and an ultrasonic sensor for obstacle avoidance. The Node MCU ESP32 serves as the central controller, transmitting real-time data to the Blynk IoT platform for remote monitoring. In emergencies, the SIM800 GSM module triggers SMS alerts to authorized personnel, while on-site LED indicators and a buzzer provide immediate warnings. Powered by a rechargeable battery, the system ensures portability and continuous operation in remote mining areas. Experimental results demonstrate the robot’s efficacy in detecting hazards, enabling proactive safety measures, and reducing human risk in coal mines.