Indigenous Integrated Track Monitoring System Using ESP32 with Multi-Sensor Fusion for Narrow Gauge Railway Defect Detection

Railway track defects such as surface cracks, rail gaps, misalignments, and abnormal vibrations pose critical safety risks to railway operations. Conventional manual inspection methods are time-consuming, hazardous, and inconsistent. This paper presents an Indigenous Integrated Track Monitoring System (ITMS) — a low-cost, autonomous trolley designed for narrow gauge (762 mm) railway tracks that continuously monitors track health in real time. The system integrates an ESP32 microcontroller with four sensors: MPU6050 6-axis accelerometer/gyroscope for vibration and tilt detection, HC-SR04 ultrasonic sensor for crack and surface defect identification, IR sensor for rail gap detection, and NEO-6M GPS module for precise fault location tagging. Upon fault detection, the system triggers a local buzzer alarm, sends SMS alerts via a GSM SIM800L module, logs fault data to an SD card, displays real-time readings on an OLED display, and broadcasts live sensor data over a Wi-Fi dashboard. Experimental results demonstrate a system accuracy of 94–99% across different fault categories. The total hardware cost is under Rs. 3,500 (USD 42), making it a truly indigenous solution for Indian railway maintenance.