Implementación de un sistema de monitoreo de vibraciones para el diagnóstico de estructuras metálicas de puentes mediante IoT

Abstract

This research project aimed to implement a vibration monitoring system for the analysis and structural condition assessment of metallic bridge structures using Internet of Things (IoT) technology. The study addresses the growing need for continuous structural instrumentation in critical infrastructure, particularly considering recent structural failures and deterioration cases reported in the country. An experimental methodology was conducted using a scaled suspension bridge model (Mola Structural Kit 3), which allowed the reproduction of dynamic structural behavior under controlled laboratory conditions. The monitoring system was developed based on the high-resolution MEMS accelerometer ADXL355, integrated with a LoRa ESP32 V2.0 microcontroller responsible for signal acquisition, digital processing (filtering, RMS computation, and Fast Fourier Transform – FFT), and wireless data transmission to IoT platforms, specifically ThingSpeak and RemoteXY. During the implementation phase, mechanical components were designed and fabricated, including electronic enclosures, a custom printed circuit board (PCB), a rigid structural base, and a mechanical coupling system for attachment to a horizontal vibration table. A cross-validation procedure was performed using a commercial vibration meter as a reference instrument, obtaining relative errors below 5\%, thereby confirming the accuracy and reliability of the developed IoT system. Experimental testing was conducted under two primary excitation scenarios: low-intensity and high-intensity vibration. A total of 20 representative measurements were recorded per condition. The results demonstrated consistent variations in RMS acceleration values and dominant frequency components, allowing clear differentiation between distinct excitation states. The system exhibited low end-to-end latency (acquisition–processing–visualization), enabling near real-time structural monitoring. Regarding the general objective, a fully functional IoT-based vibration monitoring system was successfully implemented, capable of continuous measurement, digital processing, and remote data transmission. The specific objectives were achieved through the construction of the scaled structural model, the development of a low-latency acquisition system, and the experimental validation of dynamic performance under controlled vibration conditions.