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Particle filter-based fatigue damage prognosis by fusing multiple degradation models

Li, Tianzhi (author), Chen, Jian (author), Yuan, Shenfang (author), Zarouchas, D. (author), Sbarufatti, Claudio (author), Cadini, Francesco (author)

Fatigue damage prognosis always requires a degradation model describing the damage evolution with time; thus, the prognostic performance highly depends on the selection of such a model. The best model should probably be case specific, calling for the fusion of multiple degradation models for a robust prognosis. In this context, this paper...

journal article 2024

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Developing health indicators for composite structures based on a two-stage semi-supervised machine learning model using acoustic emission data

Moradi, M. (author), Chiachío, Juan (author), Zarouchas, D. (author)

Composite structures are highly valued for their strength-to-weight ratio, durability, and versatility, making them ideal for a variety of applications, including aerospace, automotive, and infrastructure. However, potential damage scenarios like impact, fatigue, and corrosion can lead to premature failure and pose a threat to safety. This...

conference paper 2023

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A Comprehensive Study on Measurement Accuracy of Distributed Fiber Optic Sensors Embedded within Capillaries of Solid Structures

Xiao, Y. (author), Rans, C.D. (author), Zarouchas, D. (author), Benedictus, R. (author)

Embedding fiber optic sensors (FOSs) within parts for strain measurement is attracting widespread interest due to its great potential in the field of structural health monitoring (SHM). This work proposes a novel method of embedding FOSs using capillaries within solid structures and investigates fiber positions and orientation uncertainties...

journal article 2023

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Delamination Size Prediction for Compressive Fatigue Loaded Composite Structures Via Ultrasonic Guided Wave Based Structural Health Monitoring

Gul, F.C. (author), Moradi, M. (author), Benedictus, R. (author), HADJRIA, RAFIK (author), LUGOVTSOVA, YEVGENIYA (author), Zarouchas, D. (author)

Under in-plane compressive load conditions, the growth of a delamination initially induced by an impact can be followed by a fast growth after a threshold level, which leads to a catastrophic failure in composite structures. To avoid reaching this critical level, it is essential to uncover the delamination size and growth pattern in real time....

conference paper 2023

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Advanced Health Monitoring of Composite Structures Through Deep Learning-Based Analysis of Lamb Wave Data for Developing Health Indicators

Moradi, M. (author), Gul, F.C. (author), Chiachío, Juan (author), Benedictus, R. (author), Zarouchas, D. (author)

A health indicator (HI) serves as an intermediary link between structural health monitoring (SHM) data and prognostic models, and an efficient HI should meet prognostic criteria, i.e., monotonicity, trendability, and prognosability. However, designing a proper HI for composite structures is a challenging task due to the complex damage...

conference paper 2023

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Acousto-ultrasonic composite transducers integration into thermoplastic composite structures via ultrasonic welding

Galiana, Shankar (author), Moradi, M. (author), Wierach, Peter (author), Zarouchas, D. (author)

Acousto-ultrasonic composite transducers (AUCT), which are made of piezoceramic materials embedded in a reinforced polymeric matrix, are promising for the health monitoring of composite structures. However, when they are integrated into highly loaded thermoplastic composite structures, ensuring proper joining properties is a challenge. The...

conference paper 2023

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Acoustic emission-based remaining useful life prognosis of aeronautical structures subjected to compressive fatigue loading

Galanopoulos, Georgios (author), Milanoski, Dimitrios (author), Eleftheroglou, N. (author), Broer, Agnes A.R. (author), Zarouchas, D. (author), Loutas, Theodoros (author)

An increasing interest for Structural Health Monitoring has emerged in the last decades. Acoustic emission (AE) is one of the most popular and widely studied methodologies employed for monitoring, due to its capabilities of detecting, locating and capturing the evolution of damage. Most literature so far, has employed AE for characterizing...

journal article 2023

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A data driven methodology for upscaling remaining useful life predictions: From single- to multi-stiffened composite panels

Galanopoulos, Georgios (author), Fytsilis, Efthimios (author), Yue, N. (author), Broer, Agnes A.R. (author), Milanoski, Dimitrios (author), Zarouchas, D. (author), Loutas, Theodoros (author)

In this paper we execute a complex test campaign to develop a novel methodology for the Remaining Useful Life (RUL) estimation of complex multi-stiffened composite aeronautical panels utilizing Machine Learning models trained with Structural Health Monitoring (SHM) data from hierarchically simpler elements, i.e., single-stiffened panels....

journal article 2023

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An SHM Data-Driven Methodology for the Remaining Useful Life Prognosis of Aeronautical Subcomponents

Galanopoulos, Georgios (author), Eleftheroglou, N. (author), Milanoski, Dimitrios (author), Broer, Agnes A.R. (author), Zarouchas, D. (author), Loutas, Theodoros (author)

Prognosis of the Remaining Useful Life (RUL) of a structure from Structural Health Monitoring data is the ultimate level in the SHM hierarchy. Reliable prognostics are key to a Condition Based Maintenance paradigm for aerospace systems and structures. In the present work, we propose a methodology for RUL prognosis of generic aeronautical...

conference paper 2023

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Intelligent Health Indicators Based on Semi-supervised Learning Utilizing Acoustic Emission Data

Moradi, M. (author), Broer, Agnes A.R. (author), Chiachío, Juan (author), Benedictus, R. (author), Zarouchas, D. (author)

Health indicators are indices that act as intermediary links between raw SHM data and prognostic models. An efficient HI should satisfy prognostic requirements such as monotonicity, trendability, and prognosability in such a way that it can be effectively used as an input in a prognostic model for remaining useful life estimation. However,...

conference paper 2023

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Intelligent health indicator construction for prognostics of composite structures utilizing a semi-supervised deep neural network and SHM data

Moradi, M. (author), Broer, Agnes A.R. (author), Chiachío, Juan (author), Benedictus, R. (author), Loutas, Theodoros H. (author), Zarouchas, D. (author)

A health indicator (HI) is a valuable index demonstrating the health level of an engineering system or structure, which is a direct intermediate connection between raw signals collected by structural health monitoring (SHM) methods and prognostic models for remaining useful life estimation. An appropriate HI should conform to prognostic...

journal article 2023

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Condition-Based Maintenance in Aviation: Challenges and Opportunities

Verhagen, W.J.C. (author), Santos, Bruno F. (author), Freeman, Floris (author), van Kessel, Paul (author), Zarouchas, D. (author), Loutas, Theodoros (author), Yeun, R.C.K. (author), Heiets, I. (author)

Condition-Based Maintenance (CBM) is a policy that uses information about the health condition of systems and structures to identify optimal maintenance interventions over time, increasing the efficiency of maintenance operations. Despite CBM being a well-established concept in academic research, the practical uptake in aviation needs to catch...

journal article 2023

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Structural integrity assessment of a full-scale adhesively-bonded bi-material joint for maritime applications

Saeedifar, M. (author), Saleh, M. (author), Krairi, Anouar (author), Teixeira De Freitas, S. (author), Zarouchas, D. (author)

The present study proposes a comprehensive integrity assessment approach for a full-scale adhesively-bonded bi-material joint for maritime applications. The joint represents a cross-section of the bond-line connection of a ship with a steel hull and a sandwich composite superstructure. The full-scale joint consists of a sandwich composite...

journal article 2023

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A novel strain-based health indicator for the remaining useful life estimation of degrading composite structures

Galanopoulos, Georgios (author), Eleftheroglou, N. (author), Milanoski, Dimitrios (author), Broer, Agnes A.R. (author), Zarouchas, D. (author), Loutas, Theodoros (author)

We present a generic methodology for developing a Health Indicator out of strain-based Structural Health Monitoring data suitable for implementation in prognostic tasks. For this purpose, an in-house test campaign is launched. Single-stringered composite panels are subjected to compression-compression fatigue with the strains being monitored...

journal article 2023

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Probability of Delamination Detection for CFRP DCB Specimens Using Rayleigh Distributed Optical Fiber Sensors

Falcetelli, F. (author), Cristiani, D.L.M. (author), Yue, N. (author), Sbarufatti, Claudio (author), Sante, Raffaella Di (author), Zarouchas, D. (author)

Distributed Optical Fiber Sensors (DOFS) show several inherent benefits with respect to conventional strain-sensing technologies and represent a key technology for Structural Health Monitoring (SHM). Despite the solid motivation behind DOFS-based SHM systems, their implementation for real-time structural assessment is still unsatisfactory...

conference paper 2023

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Damage Diagnostics on Post-buckled Stiffened Panels Utilizing the Digital-Twin Concept

Milanoski, Dimitrios (author), Galanopoulos, Georgios (author), Zarouchas, D. (author), Loutas, Theodoros (author)

A digital twin representative of a typical composite stiffened panel is utilized to monitor skin-to-stringer disbonds. A validated finite element model of the composite panel estimates the longitudinal strains of the pristine state, at the exact location where integrated fiber Bragg grating sensors are permanently installed. Experimental...

conference paper 2023

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Assessing stiffness degradation of stiffened composite panels in post-buckling compression-compression fatigue using guided waves

Yue, N. (author), Broer, Agnes A.R. (author), Briand, William (author), Rébillat, Marc (author), Loutas, Theodoros (author), Zarouchas, D. (author)

The application of structural health monitoring (SHM) in composite airframe structural elements under long-term realistic fatigue loading needs to consider the structural behavior on the global level, which is an intricate task. The overall structural stiffness is a key design parameter for composite structures and the stiffness degradation...

journal article 2022

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Interpretable neural network with limited weights for constructing simple and explainable HI using SHM data

Moradi, M. (author), Komninos, P. (author), Benedictus, R. (author), Zarouchas, D. (author)

Recently, companies all over the world have been focusing on the improvement of autonomous health management systems in order to enhance performance and reduce downtime costs. To achieve this, the remaining useful life predictions have been given remarkable attention. These predictions depend on the proper designing process and the quality of...

conference paper 2022

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Qualification of distributed optical fiber sensors using probability of detection curves for delamination in composite laminates

Falcetelli, F. (author), Cristiani, D.L.M. (author), Yue, N. (author), Sbarufatti, Claudio (author), Troiani, Enrico (author), Di Sante, Raffaella (author), Zarouchas, D. (author)

Despite the promising application of Distributed Optical Fiber Sensors (DOFS) in monitoring damage in composite structures, their implementation outside academia is still unsatisfactory due to the lack of a systematic approach to assessing their damage detection performance. The existing tool developed for non-destructive evaluation,...

journal article 2022

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Multi-level damage diagnosis on stiffened composite panels based on a damage-uninformative digital twin

Milanoski, Dimitrios (author), Galanopoulos, Georgios (author), Zarouchas, D. (author), Loutas, Theodoros (author)

In this study, a multi-level Structural Health Monitoring methodology for stiffened composite panels is introduced. A digital twin (DT), that is, a three-dimensional finite element (FE) model, representing the pristine state baseline of the test article, is developed and verified for compressive loading in the post-buckling regime. The...

journal article 2022