Wireless Crack Detection System Based on IoT and Acoustic Emission

This paper proposes a Wireless Crack Detection System (WCDS) for concrete structures based on IoT and Acoustic Emission (AE). A crack is a rupture inside the building material occurring due stress, aging, and other damaging factors. When a crack occurs, energy is released in term of an ultrasonic wave, also, known as AE. The WCDS objective is to timely detect cracks and wirelessly transmit the collected data to a central server for analysis. The AE sensor captures the crack signals, which undergo analogy signal processing to improve signal quality and remove noise. The acquired signals are analysed, and if a crack is detected, the proposed system extracts the features from the signal, generates a GPS-based timestamp with microsecond accuracy, and uses the MQTT protocol to send the data to the server (Raspberry Pi). Node-RED is utilized for data visualization, making it simple for users to monitor the system and study the crack signals.