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Virtual sensing of subsoil strain response in monopile-based offshore wind turbines via Gaussian process latent force models

Zou, Joanna (author), Lourens, E. (author), Cicirello, A. (author)

Virtual sensing techniques have gained traction in applications to the structural health monitoring of monopile-based offshore wind turbines, as the strain response below the mudline, which is a primary indicator of fatigue damage accumulation, is impractical to measure directly with physical instrumentation. The Gaussian process latent force...

journal article 2023

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Roadmap on measurement technologies for next generation structural health monitoring systems

Laflamme, Simon (author), Ubertini, Filippo (author), Di Matteo, Alberto (author), Pirrotta, Antonina (author), Perry, Marcus (author), Fu, Yuguang (author), Glisic, Branko (author), Shu, Yening (author), Giardina, Giorgia (author)

Structural health monitoring (SHM) is the automation of the condition assessment process of an engineered system. When applied to geometrically large components or structures, such as those found in civil and aerospace infrastructure and systems, a critical challenge is in designing the sensing solution that could yield actionable information...

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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Barely visible impact damage detection in composite structures using deep learning networks with varying complexities

Tabatabaeian, A. (author), Jerkovic, Bruno (author), Harrison, Philip (author), Marchiori, Elena (author), Fotouhi, M. (author)

Visual inspection is one of the most common non-destructive testing (NDT) methods that offers a fast evaluation of surface damage in aerospace composite structures. However, it is highly dependent on human-related factors and may not detect barely visible impact damage (BVID). In this research, low velocity impact tests with different energy...

journal article 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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Digital Thread Roadmap for Manufacturing and Health Monitoring the Life Cycle of Composite Aerospace Components

Eskue, N.D. (author)

This paper provides a detailed review of a digital thread for composite aerospace components. The current state of the digital thread continues to progress and at an ever-accelerating rate due to advancements in supporting technologies such as AI, data capture/processing/storage, sensors, simulation, and blockchain. While the individual steps...

review 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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Bayesian system identification for structures considering spatial and temporal correlation

Koune, I.C. (author), Rózsás, Árpád (author), Slobbe, Arthur (author), Cicirello, A. (author)

The decreasing cost and improved sensor and monitoring system technology (e.g., fiber optics and strain gauges) have led to more measurements in close proximity to each other. When using such spatially dense measurement data in Bayesian system identification strategies, the correlation in the model prediction error can become significant. The...

journal article 2023

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Acoustic Emission Monitoring of Naturally Developed Damage in Large-scale Low-speed Roller Bearings

Scheeren, B. (author), Kaminski, M.L. (author), Pahlavan, Lotfollah (author)

This article presents an approach to identify naturally developed damage in low-speed bearings using waveform-similarity-based clustering of acoustic emissions (AEs) under fatigue loading. The approach is motivated by the notation that each recorded AE signal from a particular damage is defined by the convolution of the source signal, transfer...

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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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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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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Fibre Optic Shape Sensing and Load Monitoring of Adaptive Aerospace Structures

Nazeer, N. (author)

The aerospace industry is an ever-evolving field that has seen many technological advances over the past decades. The desire for aircraft to be not only efficient and reliable but also cheaper and safer has brought about many proposals across the industry. One of these advances is towards morphing aircraft wings to make wings lighter, more...

doctoral thesis 2022

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An efficient and robust sampler for Bayesian inference: Transitional Ensemble Markov Chain Monte Carlo

Lye, Adolphus (author), Cicirello, A. (author), Patelli, Edoardo (author)

Bayesian inference is a popular approach towards parameter identification in engineering problems. Such technique would involve iterative sampling methods which are often robust. However, these sampling methods often require significant computational resources and also the tuning of a large number of parameters. This motivates the development...

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

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Use of dictionary learning for damage localization in complex structures

Nokhbatolfoghahai, A. (author), M. Navazi, H. (author), Groves, R.M. (author)

In this paper, to increase the performance of the sparse reconstruction method in real complex engineering structures an adaptive dictionary learning framework is proposed which updates the dictionary matrix, to allow improved compatibility with the complex structure. This proposed framework was developed by combining analytical modeling with...

journal article 2022

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The Need for Multi-Sensor Data Fusion in Structural Health Monitoring of Composite Aircraft Structures

Broer, Agnes A.R. (author), Benedictus, R. (author), Zarouchas, D. (author)

With the increased use of composites in aircraft, many new successful contributions to the advancement of the structural health monitoring (SHM) field for composite aerospace structures have been achieved. Yet its application is still not often seen in operational conditions in the aircraft industry, mostly due to a gap between research focus...

journal article 2022

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A Framework for Optimal Sensor Placement to Support Structural Health Monitoring

Li, Shen (author), Coraddu, A. (author), Brennan, Feargal (author)

Offshore or drydock inspection performed by trained surveyors is required within the integrity management of an in-service marine structure to ensure safety and fitness for purpose. However, these physical inspection activities can lead to a considerable increase in lifecycle cost and significant downtime, and they can impose hazards for the...

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