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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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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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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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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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Smart hybrid composite sensor technology to enhance the detection of low energy impact damage in composite structures

Fotouhi, Sakineh (author), Jalalvand, Meisam (author), Wisnom, Michael R. (author), Fotouhi, M. (author)

This paper introduces novel structural health monitoring (SHM) sensors to improve the detection of low energy impact damage in laminated composites. The sensor is a purposely designed thin-ply hybrid composite, composed of a layer of unidirectional S-glass/epoxy and another layer of unidirectional ultra-high modulus (UHM) carbon/epoxy. The...

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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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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A hybrid methodology for structural damage detection uniting FEM and 1D-CNNs: Demonstration on typical high-pile wharf: Demonstration on typical high-pile wharf

Zhou, Yujue (author), Zheng, Yonglai (author), Liu, Yongcheng (author), Pan, Tanbo (author), Zhou, Y. (author)

Vibration-based structural damage detection (SDD) has been a subject of intense research in structural health monitoring (SHM) for large civil engineering structures over the decades. The performance of the conventional SDD approaches predominantly relies on the rational choices of the damage feature and classifier. Hand-crafted features or...

journal article 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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Assessment of the Measurement Performance of the Multimodal Fibre Optic Shape Sensing Configuration for a Morphing Wing Section

Nazeer, N. (author), Groves, R.M. (author), Benedictus, R. (author)

In this paper, with the final aim of shape sensing for a morphing aircraft wing section, a developed multimodal shape sensing system is analysed. We utilise the method of interrogating a morphing wing section based on the principles of both hybrid interferometry and Fibre Bragg Grating (FBG) spectral sensing described in our previous work....

journal article 2022

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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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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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Static and dynamic testing of delamination in hybrid SHCC/concrete beams

Cabboi, A. (author), Harrass, Othman (author), Sánchez Gómez, S. (author), Lukovic, M. (author)

The focus of this study is to characterize delamination using static and dynamic tests and to assess the interface failure mechanism of an innovative hybrid concrete beam, made out of conventional concrete and a special class of fibre reinforced material, known as Strain Hardening Cementitious Composite (SHCC). Three SHCC beams were subject to...

journal article 2021

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Evaluation of the sparse reconstruction and the delay-and-sum damage imaging methods for structural health monitoring under different environmental and operational conditions

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

In this paper, the performance of the sparse reconstruction (SR) and the delay-and-sun (DAS) methods for damage localization, were evaluated for various environmental and operational conditions, both numerically and experimentally. To assess these damage localization methods, a methodology based on the Taguchi method was used to make the...

journal article 2021

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A general substructure-based framework for input-state estimation using limited output measurements

Tatsis, K. E. (author), Dertimanis, V. K. (author), Papadimitriou, C. (author), Lourens, E. (author), Chatzi, E. N. (author)

This paper presents a general framework for estimating the state and unknown inputs at the level of a system subdomain using a limited number of output measurements, enabling thus the component-based vibration monitoring or control and providing a novel approach to model updating and hybrid testing applications. Under the premise that the...

journal article 2021

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Health monitoring of aerospace structures utilizing novel health indicators extracted from complex strain and acoustic emission data

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

The development of health indicators (HI) of diagnostic and prognostic potential from generally uninformative raw sensor data is both a challenge and an essential feature for data‐driven diagnostics and prognostics of composite structures. In this study, new damage‐sensitive features, developed from strains acquired with Fiber Bragg Grating ...

journal article 2021

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Sensing, actuation, and control of the smartx prototype morphing wing in the wind tunnel

Nazeer, N. (author), Wang, Xuerui (author), Groves, R.M. (author)

This paper presents a study on trailing edge deflection estimation for the SmartX camber morphing wing demonstrator. This demonstrator integrates the technologies of smart sensing, smart actuation and smart controls using a six module distributed morphing concept. The morphing sequence is brought about by two actuators present at both ends of...

journal article 2021

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Perception modelling by invariant representation of deep learning for automated structural diagnostic in aircraft maintenance: A study case using DeepSHM

Ewald, Vincentius (author), Sridaran Venkat, Ramanan (author), Asokkumar, Aadhik (author), Benedictus, R. (author), Boller, Christian (author), Groves, R.M. (author)

Predictive maintenance, as one of the core components of Industry 4.0, takes a proactive approach to maintain machines and systems in good order to keep downtime to a minimum and the airline maintenance industry is not an exception to this. To achieve this goal, practices in Structural Health Monitoring (SHM) complement the existing Non...

journal article 2021