@agh.edu.pl
Department of Robotics and Mechatronics
AGH University of Science and Technology
Structural Health Monitoring, Structural Dynamics, Smart materials and Structures, Advanced signal processing, Machine learning
Scopus Publications
Rafał Radecki, Wojciech Trybulec, Mariusz Osika, and Wiesław J. Staszewski
Elsevier BV
Phong B. Dao, Tomasz Barszcz, and Wieslaw J. Staszewski
Elsevier BV
Rafał Radecki and Wiesław J. Staszewski
MDPI AG
Material nonlinearity is explored for the assessment of structural integrity. Crack–wave interactions are of particular interest. The major focus is on higher-order harmonics, generated in propagating shear horizontal (SH) waves. These harmonics are generated due to global material nonlinearity and local effects such as fatigue cracks. The theoretical background of the proposed method is explained. The method is examined using numerical simulations and experimental tests. The former involves the Local Interaction Simulation Approach (LISA), implemented for the nonlinear shear horizontal wavefield. The latter is based on a high-frequency shear excitation approach. Experimental tests are conducted using a series of beam specimens with fatigue cracks. Low-profile, surface-bonded piezoceramic shear actuators are used for excitation. The excitation frequency is selected to minimize the number of generated modes in the examined specimens. Nonlinear ultrasonic responses are collected using a non-contact laser vibrometer. The results show that higher-order harmonic generation—based on shear horizontal wave propagation—can be used for crack detection in the presence of global material nonlinearity.
Emil Aleksiewicz-Drab, Aleksandra Ziaja-Sujdak, Rafał Radecki, and Wiesław J. Staszewski
MDPI AG
In this paper, piezoceramic-based excitation of shear horizontal waves is investigated. A thickness-shear d15 piezoceramic transducer is modeled using the finite-element method. The major focus is on the directivity and excitability of the shear horizontal fundamental mode with respect to the maximization of excited shear and minimization of Lamb wave modes. The results show that the geometry of the transducer has more effect on the directivity than on the excitability of the analyzed actuator. Numerically simulated results are validated experimentally. The experimental results show that transducer bonding significantly affects the directivity and amplitude of the excited modes. In conclusion, when the selected actuator is used for shear excitation, the best solution is to tailor the transducer in such a way that at the resonant frequency the desired directivity is achieved.
Jan Długosz, Phong B. Dao, Wiesław J. Staszewski, and Tadeusz Uhl
MDPI AG
Hyperspectral imaging (HSI) is a remote sensing technique that has been successfully applied for the task of damage detection in glass fibre-reinforced plastic (GFRP) materials. Similarly to other vision-based detection methods, one of the drawbacks of HSI is its susceptibility to the lighting conditions during the imaging, which is a serious issue for gathering hyperspectral data in real-life scenarios. In this study, a data conditioning procedure is proposed for improving the results of damage detection with various classifiers. The developed procedure is based on the concept of signal stationarity and cointegration analysis, and achieves its goal by performing the detection and removal of the non-stationary trends in hyperspectral images caused by imperfect lighting. To evaluate the effectiveness of the proposed method, two damage detection tests have been performed on a damaged GFRP specimen: one using the proposed method, and one using an established damage detection workflow, based on the works of other authors. Application of the proposed procedure in the processing of a hyperspectral image of a damaged GFRP specimen resulted in significantly improved accuracy, sensitivity, and F-score, independently of the type of classifier used.
Shengbo Shan, Yuanman Zhang, Ze Liu, Fuzhen Wen, Li Cheng, and Wieslaw J Staszewski
Elsevier BV
Frank H.G. Stolze, Keith Worden, Graeme Manson, and Wieslaw J. Staszewski
Elsevier BV
M. Osika, A. Ziaja–Sujdak, R. Radecki, and W.J. Staszewski
Elsevier BV
Phong B. Dao and Wieslaw J. Staszewski
Elsevier BV
Frank H. G. Stolze, Keith Worden, Graeme Manson, and Wieslaw J. Staszewski
MDPI AG
Structural health monitoring of riveted aircraft panels is a real challenge for maintenance engineers. Here, a diffused Lamb wave field is used for fatigue-crack detection in a multi-riveted strap-joint aircraft panel. The panel is instrumented with a network of low-profile surface-bonded piezoceramic transducers. Various amplitude characteristics of Lamb waves are used to extract information on fatigue damage. A statistical outlier analysis based on these characteristics is also performed to detect damage. The experimental work is supported by simplified modelling of wave scattering from crack tips to explain complex response features. The Local Interaction Simulation Approach (LISA) is used for this modelling task. The results demonstrate the potential and limitations of the method for reliable fatigue-crack detection in complex aircraft components.
Dariusz Broda, Krzysztof Mendrok, Vadim V. Silberschmidt, Lukasz Pieczonka, and Wieslaw J. Staszewski
MDPI AG
The nonlinear interaction of longitudinal vibration and ultrasound in beams with cracks is investigated. The central focus is on the localization effect of this interaction, i.e., the locally enhanced nonlinear vibro-acoustic modulation. Both numerical and experimental investigations are undertaken. The finite element (FE) method is used to investigate different crack models, including the bi-linear crack, open crack, and breathing crack. A parametric study is performed considering different crack depths, locations, and boundary conditions in a two-dimensional beam model. The study shows that observed nonlinearities (i.e., nonlinear crack–wave modulations) are particularly strong in the vicinity of the crack, allowing not only for crack localization but also for the separation of the crack-induced nonlinearity from other sources of nonlinearity.
Wojciech Trubulec, Rafal Radecki, Mariusz Osika, Aleksandra Ziaja-Sujdak, and Wieslaw J. Staszewski
SPIE
Recent years have brought more attention to new damage detection approaches based on nonlinear phenomena associated with Shear Horizontal (SH) waves. Many nonlinear effects–previously observed in ultrasonic wave propagation–have been considered for structural damage detection. The major effort has been put on classical nonlinear effects, such as higher harmonic generation. More recently, nonlinear vibro-acoustic modulation and modulation transfer mechanisms have been also observed in SH wave propagation. However, these phenomena have not been used for structural damage detection. The paper attempts to fulfill this gap. The proposed method involves two excitation waves. The low-frequency pumping wave is used for damage perturbation. In addition, high-frequency SH wave is used as a probing wave. The probing wave is modulated by the pumping wave in the presence of structural damage. The method is used in the paper for fatigue crack detection in metallic structural components. The results demonstrate that the proposed approach has a potential for structural damage detection. Previous research work demonstrates that classical nonlinear effects (e.g., higher harmonic generation) observed in SH waves offer better sensitivity to material microdefects than similar effects observed in longitudinal wave propagation. Therefore, it is anticipated that non-classical nonlinear affects associated with SH wave propagation will show similar potential. However, more research work is needed to confirm this assumption.
Jakub Nowak, Mariusz Osika, Rafal Radecki, Aleksandra Ziaja-Sujdak, and Wieslaw J. Staszewski
SPIE
Various classical and non-classical nonlinear effects have been observed in ultrasonic wave propagation and used for contact-type damage detection. The former relates to higher harmonic generation, whereas the latter is based nonlinear vibro-acoustic modulations effects. More recently both nonlinear effects have been observed in shear horizontal wave propagation. However, the nonlinear crack-wave interaction is still not fully understood. It is assumed that this interaction is enhanced by local nonlinear elasticity and dissipation of elastic waves. The latter effect is the major focus of the paper. Previous experimental research studies demonstrate that high-frequency ultrasonic waves propagation through crack faces that are in contact–and perturbed by low-frequency excitation–exhibit local nonlinear effects of elastic and dissipative nature. The amplitude level of these effects depends on applied stresses. Both nonlinear effects have a great potential for structural damage detection. However, more theoretical and modelling research work is needed to fully understand these non-classical nonlinear effects. Numerical simulations based on nonlinear crack-wave interaction are investigated in the paper. Three models of local nonlinearity are investigated. These are: the Coulomb friction, the nonlinear viscous damping and the hysteretic stress-strain models. Nonlinear wavefield distortions–due to crack-wave interactions–are observed and analyzed. Numerical simulations are performed using the Local Interaction Simulation Approach (LISA), implemented for shear horizontal wave propagation. Wave amplitudes corresponding to generated higher harmonics and modulated sidebands are investigated in the presented work.
Kajetan Dziedziech, Krzysztof Mendrok, Tadeusz Uhl, and Wiesław J. Staszewski
CRC Press
R. Radecki, A. Ziaja-Sujdak, M. Osika, and W.J. Staszewski*
CRC Press
Aleksandra Ziaja-Sujdak, Mariusz Osika, Rafal Radecki, and Wieslaw J. Staszewski
Springer International Publishing
Mariusz Osika, Aleksandra Ziaja-Sujdak, Rafal Radecki, and Wieslaw J. Staszewski
Springer International Publishing
Rafal Radecki, Aleksandra Ziaja-Sujdak, Mariusz Osika, and Wieslaw J. Staszewski
Springer International Publishing
Jan Długosz, Phong Ba Dao, Wiesław J. Staszewski, and Tadeusz Uhl
Springer International Publishing
M. Osika, A. Ziaja-Sujdak, R. Radecki, L. Cheng, and W.J. Staszewski
Elsevier BV
Krzysztof Czeluśniak, Wiesław J. Staszewski, and Francesco Aymerich
Elsevier BV
Kajetan Dziedziech, Wiesław Jerzy Staszewski, Krzysztof Mendrok, and Biswajit Basu
MDPI AG
Short-time, abrupt events—such as earthquakes and other shock loadings—often lead to damage that is difficult to detect in structures using output-only vibration measurements. The time-variant transmissibility is proposed to tackle this problem. The approach is based on two-dimensional wavelet power spectra. The time-frequency transmissibility and relevant coherence function are used for structural damage detection in structural elements in buildings. Numerical simulations and experimental tests are used in these investigations. The results are compared with the classical transmissibility and time-variant input-output wavelet approach. The paper shows that output-only measurements and wavelet-based transmissibility can be used to monitor abrupt damage-related changes to structural dynamics.
P.B. Dao
Materials Research Forum LLC
Abstract. The cointegration method has recently attracted a growing interest from scientists and engineers as a promising tool for the development of wind turbine condition monitoring systems. This paper presents a short review of cointegration-based techniques developed for condition monitoring and fault detection of wind turbines. In all reported applications, cointegration residuals are used in control charts for condition monitoring and early failure detection. This is known as the residual-based control chart approach. Vibration signals and SCADA data are typically used with cointegration in these applications. This is due to the fact that vibration-based condition monitoring is one of the most common and effective techniques (used for wind turbines); and the use of SCADA data for condition monitoring and fault detection of wind turbines has become more and more popular in recent years.
Phong B. Dao and Wieslaw J. Staszewski
MDPI AG
Lamb waves have been widely used for structural damage detection. However, practical applications of this technique are still limited. One of the main reasons is due to the complexity of Lamb wave propagation modes. Therefore, instead of directly analysing and interpreting Lamb wave propagation modes for information about health conditions of the structure, this study has proposed another approach that is based on statistical analyses of the stationarity of Lamb waves. The method is validated by using Lamb wave data from intact and damaged aluminium plates exposed to temperature variations. Four popular unit root testing methods, including Augmented Dickey–Fuller (ADF) test, Kwiatkowski–Phillips–Schmidt–Shin (KPSS) test, Phillips–Perron (PP) test, and Leybourne–McCabe (LM) test, have been investigated and compared in order to understand and make statistical inference about the stationarity of Lamb wave data before and after hole damages are introduced to the aluminium plate. The separation between t-statistic features, obtained from the unit root tests on Lamb wave data, is used for damage detection. The results show that both ADF test and KPSS test can detect damage, while both PP and LM tests were not significant for identifying damage. Moreover, the ADF test was more stable with respect to temperature changes than the KPSS test. However, the KPSS test can detect damage better than the ADF test. Moreover, both KPSS and ADF tests can consistently detect damages in conditions where temperatures vary below 60 °C. However, their t-statistics fluctuate more (or less homogeneous) for temperatures higher than 65 °C. This suggests that both ADF and KPSS tests should be used together for Lamb wave based structural damage detection. The proposed stationarity-based approach is motivated by its simplicity and efficiency. Since the method is based on the concept of stationarity of a time series, it can find applications not only in Lamb wave based SHM but also in condition monitoring and fault diagnosis of industrial systems.
Fuzhen Wen, Shengbo Shan, Rafal Radecki, Wieslaw J Staszewski, and Li Cheng
IOP Publishing
Abstract The fundamental shear horizontal (SH) wave in thin-walled structures shows appealing features for structural health monitoring (SHM) applications. Its efficient generation and reception however remain a critical and challenging issue. Magnetostrictive transducers (MsTs) show proven ability in exciting strong SH waves due to the high piezomagnetic coefficient of the ferromagnetic foil. In this study, to investigate the fundamental SH wave generation using MsTs and their design, a theoretical model is established based on the shear-lag model and the normal mode expansion method. The coupling of an MsT with a host plate is achieved by a bonding layer, whose mechanical property is modelled through the continuous shear stress across the thickness. The theoretical model is validated using finite element simulations in terms of generation mechanism and some typical features associated with the fundamental SH wave component. Meanwhile, wave field is visualized using a 3D Laser scanning vibrometer system. Experimental results within a wide frequency range show a good agreement with the theoretically predicted results. Influences of the coil configuration and bonding conditions are further investigated using the proposed model. The study offers guidelines to system design and optimization for fundamental SH wave generation in views of guided-wave-based SHM applications.