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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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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

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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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Acoustic Emission Monitoring of Carbon Fibre Reinforced Composites with Embedded Sensors for In-Situ Damage Identification

Huijer, A.J. (author), Kassapoglou, C. (author), Pahlavan, Lotfollah (author)

Piezoelectric sensors can be embedded in carbon fibre-reinforced plastics (CFRP) for continuous measurement of acoustic emissions (AE) without the sensor being exposed or disrupting hydro- or aerodynamics. Insights into the sensitivity of the embedded sensor are essential for accurate identification of AE sources. Embedded sensors are considered...

journal article 2021

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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

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Damage assessment of a titanium skin adhesively bonded to carbon fiber–reinforced plastic omega stringers using acoustic emission

Saeedifar, M. (author), Saleh, M. (author), Nijhuis, Peter (author), Teixeira De Freitas, S. (author), Zarouchas, D. (author)

This study is devoted to the use of acoustic emission technique for a comprehensive damage assessment, that is, damage detection, localization, and classification, of an aeronautical metal-to-composite bonded panel. The structure comprised a titanium panel adhesively bonded to carbon fiber–reinforced plastic omega stringers. The panel contained...

journal article 2021

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Broadband signal reconstruction for SHM: An experimental and numerical time reversal methodology

Falcetelli, F. (author), Venturini, Nicolas (author), Barroso Romero, M. (author), Martinez, Marcias J. (author), Pant, Shashank (author), Troiani, Enrico (author)

Structural Health Monitoring (SHM) aims to shift aircraft maintenance from a time-based to a condition-based approach. Within all the SHM techniques, Acoustic Emission (AE) allows for the monitoring of large areas by analyzing Lamb waves propagating in plate like structures. In this study, the authors proposed a Time Reversal (TR) methodology...

journal article 2021

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Load monitoring of a cantilever plate by a novel multimodal fibre optic sensing configuration

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

Abstract: Optical fibre sensors and in particular fibre Bragg gratings (FBG) have received a lot of interest for Structural Health Monitoring in different application fields, such as aerospace, pipeline and civil engineering. FBGs are conventionally used to monitor strain and sometimes temperature. In this paper, we propose a new method for...

journal article 2021

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Planning low-error SHM strategy by constrained observability method

Peng, Tian (author), Nogal Macho, M. (author), Casas, Joan R. (author), Turmo, Jose (author)

Structural identification using dynamical parameters (such as the natural vibration frequencies and mode shapes) is an important issue, especially in bridges or high-rise buildings. However, incorrect decisions could happen on the Structural Health Monitoring (SHM) strategy and the Structural System Identification (SSI) analysis that makes...

journal article 2021

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Integrated InSAR monitoring and structural assessment of tunnelling-induced building deformations

Macchiarulo, V. (author), Milillo, Pietro (author), DeJong, Matthew J. (author), González Martí, Javier (author), Sánchez, Jordi (author), Giardina, Giorgia (author)

Structural deformation monitoring is crucial for the identification of early signs of tunnelling-induced damage to adjacent structures and for the improvement of current damage assessment procedures. Satellite multi-temporal interferometric synthetic aperture radar (MT-InSAR) techniques enable measurement of building displacements over time...

journal article 2021

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Effects of high-amplitude low-frequency structural vibrations and machinery sound waves on ultrasonic guided wave propagation for health monitoring of composite aircraft primary structures

Ochôa, Pedro (author), Groves, R.M. (author), Benedictus, R. (author)

A reliable damage diagnostic by ultrasonic guided wave (GW) based structural health monitoring (SHM) can only be achieved if the physical interactions between wave propagation, the SHM system and environmental factors are fully understood. The purpose of this research was to gain knowledge about the effects of high-amplitude low-frequency...

journal article 2020