Miniaturized IoT-based systems for structural integrity and health monitoring
File(s)
Author(s)
Dagsever, Fatih
Type
Thesis
Abstract
This PhD research presents the design, development, and validation of miniaturized IoT-based Structural Health Monitoring (SHM) systems to improve the reliability and safety of composite structures. Conventional SHM approaches are often constrained by extensive cabling, limited scalability, and bulky data acquisition units, posing significant challenges in weight-sensitive aerospace applications. To overcome these limitations, this work introduces novel miniaturized wireless SHM platforms.
The first proposed system integrates a multi-layer Printed Circuit Board (PCB), a Wireless Sensor Network (WSN), and a Graphical User Interface (GUI), providing real-time data acquisition while significantly reducing wiring complexity through ZigBee-based communication. The second system, a Passive Sensing Node, is designed for impact detection and localization, operating with a coin-cell battery-powered event-triggered comparator. Using Bluetooth Low Energy (LE) and a shared clock for time synchronization, it enables ultra-low-power operation with immediate response to impact events.
Building upon these developments, the third system is a multi-sensor platform that unifies a piezoelectric transducer, a strain gauge, an accelerometer, and an environmental sensor on a compact 3×3 cm flexible PCB. Designed for low-power Bluetooth LE communication, it enables multi-modal data acquisition for comprehensive condition monitoring. Finally, the fourth system integrates active and passive sensing within a single platform, combining an external Analog-to-Digital Converter (ADC) and a Digital-to-Analog Converter (DAC) to facilitate both guided wave-based inspections and spontaneous impact detection. In passive mode, impact-induced signals are captured and transmitted wirelessly, while in active mode, the system successfully generates actuation signals such as tone bursts for structural evaluation.
Collectively, these proposed systems offer a comprehensive solution to on-board SHM, focusing on miniaturization, wireless data transmission, light-weight, and energy efficiency along with a user interface. Experimental tests on composite panels confirm their capability for real-time SHM and highlight their potential to protect the structural integrity of composite structures.
The first proposed system integrates a multi-layer Printed Circuit Board (PCB), a Wireless Sensor Network (WSN), and a Graphical User Interface (GUI), providing real-time data acquisition while significantly reducing wiring complexity through ZigBee-based communication. The second system, a Passive Sensing Node, is designed for impact detection and localization, operating with a coin-cell battery-powered event-triggered comparator. Using Bluetooth Low Energy (LE) and a shared clock for time synchronization, it enables ultra-low-power operation with immediate response to impact events.
Building upon these developments, the third system is a multi-sensor platform that unifies a piezoelectric transducer, a strain gauge, an accelerometer, and an environmental sensor on a compact 3×3 cm flexible PCB. Designed for low-power Bluetooth LE communication, it enables multi-modal data acquisition for comprehensive condition monitoring. Finally, the fourth system integrates active and passive sensing within a single platform, combining an external Analog-to-Digital Converter (ADC) and a Digital-to-Analog Converter (DAC) to facilitate both guided wave-based inspections and spontaneous impact detection. In passive mode, impact-induced signals are captured and transmitted wirelessly, while in active mode, the system successfully generates actuation signals such as tone bursts for structural evaluation.
Collectively, these proposed systems offer a comprehensive solution to on-board SHM, focusing on miniaturization, wireless data transmission, light-weight, and energy efficiency along with a user interface. Experimental tests on composite panels confirm their capability for real-time SHM and highlight their potential to protect the structural integrity of composite structures.
Version
Open Access
Date Issued
2025-03-13
Date Awarded
2025-07-01
Advisor
Sharif Khodaei, Zahra
Aliabadi, Mohammad Hossein
Sponsor
Turkey. Millî Eğitim Bakanlığı
Publisher Department
Department of Aeronautics
Publisher Institution
Imperial College London
Qualification Level
Doctoral
Qualification Name
Doctor of Philosophy (PhD)