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Nonlinear inversion of ultrasonic guided waves for in vivo evaluation of cortical bone properties

Chinese Physics B 2022年第7期31卷 371-378页

作者：宋小军樊天地曾俊冬石勤振黄琼顾美琳 Petro Moilanen 李义方他得安 Center for Biomedical Engineering Fudan UniversityShanghai 200433China College of Electronics and Information engineering Shanghai University of Electric PowerShanghai 200090China Department of Physics University of HelsinkiHelsinkiFinland Academy for Engineering and Technology Fudan UniversityShanghai 200433China

ultrasonic guided waves(UGWs),which propagate throughout the entire thickness of cortical bone,are attractive for the early diagnosis of osteoporosis.However,this is challenging due to the impact of soft tissue and the inherent difficulties related to multiparametric inversion of cortical bone quality factors,such as cortical thickness and bulk wave velocity.Therefore,in this research,a UGW-based multi-parameter inversion algorithm is developed to predict strength-related factors.In simulation,a free plate(cortical bone)and a bilayer plate(soft tissue and cortical bone)are used to validate the proposed method.The inversed cortical thickness(CTh),longitudinal velocity(V_(L))and transverse velocity(V_(T))are in accordance with the true values.Then four bovine cortical bone plates were used in in vitro experiments.Compared with the reference values,the relative errors for cortical thickness were 3.96%,0.83%,2.87%,and 4.25%,respectively.In the in vivo measurements,UGWs are collected from the tibias of 10 volunteers.The theoretical dispersion curves depicted by the estimated parameters(V_(T),V_(L),CTh)match well with the extracted experimental ones.In comparison with dual-energy x-ray absorptiometry,our results show that the estimated transverse velocity and cortical thickness are highly sensitive to osteoporosis.Therefore,these two parameters(CTh and V_(T))of long bones have potential to be used for diagnosis of bone status in clinical applications.

关键词： ultrasonic guided waves inversion algorithm transverse velocity bone evaluation

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Robust Damage Detection and Localization Under Complex Environmental Conditions Using Singular Value Decomposition-based Feature Extraction and One-dimensional Convolutional Neural Network

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Chinese Journal of Mechanical Engineering 2023年第3期36卷 252-261页

作者： Shengkang Zong Sheng Wang Zhitao Luo Xinkai Wu Hui Zhang Zhonghua Ni Jiangsu Key Laboratory for Design and Manufacture of Micro-Nano Biomedical Instruments School of Mechanical EngineeringSoutheast UniversityNanjing 211189China

ultrasonic guided wave is an attractive monitoring technique for large-scale structures but is vulnerable to changes in environmental and operational conditions(EOC),which are inevitable in the normal inspection of civil and mechanical structures.This paper thus presents a robust guided wave-based method for damage detection and localization under complex environmental conditions by singular value decomposition-based feature extraction and one-dimensional convolutional neural network(1D-CNN).After singular value decomposition-based feature extraction processing,a temporal robust damage index(TRDI)is extracted,and the effect of EOCs is well removed.Hence,even for the signals with a very large temperature-varying range and low signal-to-noise ratios(SNRs),the final damage detection and localization accuracy retain perfect 100%.Verifications are conducted on two different experimental datasets.The first dataset consists of guided wave signals collected from a thin aluminum plate with artificial noises,and the second is a publicly available experimental dataset of guided wave signals acquired on a composite plate with a temperature ranging from 20℃to 60℃.It is demonstrated that the proposed method can detect and localize the damage accurately and rapidly,showing great potential for application in complex and unknown EOC.

关键词： ultrasonic guided waves Singular value decomposition Damage detection and localization Environmental and operational conditions One-dimensional convolutional neural network

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Temperature Dependence of ultrasonic Longitudinal guided Wave Propagation in Long Range Steel Strands

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Chinese Journal of Mechanical Engineering 2011年第3期24卷 487-494页

作者： LIU Zenghua ZHAO Jichen WU Bin HE Cunfu College of Mechanical Engineering and Applied Electronics Technology Beijing University of Technology Beijing 100124 China

ultrasonic guided wave inspection is an effective non-destructive testing method which can be used for stress level evaluation in steel strands.Unfortunately the propagation velocity of ultrasonic guided waves changes due to temperature shift making the prestress measurement of steel strands inaccurate and even sometimes impossible.In the course of solving the problem,this paper reports on quantitative research on the temperature dependence of ultrasonic longitudinal guided wave propagation in long range steel strands.In order to achieve the generation and reception of a chosen longitudinal mode in a steel strand with a helical shaped surface,a new type of magnetostrictive transducer was developed,characterized by a group of thin clips and three identical permanent magnets.Excitation and reception of ultrasonic guided waves in a steel strand were performed experimentally.Experimental results shows that in the temperature range from-4 ℃ to 34 ℃,the propagation velocity of the L（0,1） mode at 160 kHz linearly decreased with increasing temperature and its temperature dependent coefficient was 0.90（m·s-1 ·（℃）-1） which is very close to the theoretical prediction.The effect of dimension deviation between the helical and center wires and the effect of the thermal expansion of the steel strand on ultrasonic longitudinal guided wave propagation were also analyzed.It was found that these effects could be ignored compared with the change in the material mechanical properties of the steel strands due to temperature shift.It was also observed that the longitudinal guided wave mode was somewhat more sensitive to temperature changes compared with conventional ultrasonic waves theoretically.Therefore,it is considered that the temperature effect on ultrasonic longitudinal guided wave propagation in order to improve the accuracy of stress measurement in prestressed steel strands.Quantitative research on the temperature dependence of ultrasonic guided wave propagation in steel strands provides an important basis for the compensation

关键词： steel strand ultrasonic guided waves mode temperature coefficient magnetostrictive transducer

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PROPAGATION CHARACTERISTICS OF HIGH ORDER LONGITUDINAL MODES IN STEEL STRANDS AND THEIR APPLICATIONS

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Acta Mechanica Solida Sinica 2008年第6期21卷 573-579页

作者： Zenghua Liu Su Liu Bin Wu Yinong Zhang Cunfu He College of Mechanical Engineering and Applied Electronics Technology Beijing University of Technology Beijing 100124 China

Propagation characteristics of high order longitudinal modes of ultrasonic guided waves in seven-wire steel strands are investigated theoretically and experimentally. According to these analysis results, proper longitudinal modes are selected for defect detection in steel strands. Dispersion curves for helical and central wires in a 17.80 mm nominal diameter seven-wire steel strand are numerically obtained firstly, and propagation characteristics of high-order longitudinal modes, such as wave structures, attenuation and dispersion, are analyzed. In experiments, the signals of ultrasonic guided wave at different high frequencies are excited and received at one end of a steel strand by using the same single piezoelectric transducer. The identification of longitudinal modes in the received signals is achieved based on short time Fourier transform. Furthermore, appropriate L（0, 5） mode at 2.54 MHz is chosen for detecting an artificial defect in a helical wire of the steel strand. Results show that high order longitudinal modes in a high frequency range with low dispersion and attenuation whose energy propagates mainly in the center of the wires can be used for defect detection in long range steel strands.

关键词： steel strand ultrasonic guided waves longitudinal modes dispersion attenuation

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Study of Intelligent Approaches to Identify Impact of Environmental Temperature on ultrasonic GWs Based SHM:A Review

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Journal on Artificial Intelligence 2023年第1期5卷 43-56页

作者： Saqlain Abbas Zulkarnain Abbas Xiaotong Tu Yanping Zhu Department of Mechanical Engineering University of Engineering and Technology LahoreNarowal CampusNarowal51600Pakistan Institute of Vibration Shock and NoiseState Key Laboratory of Mechanical System and VibrationShanghai Jiao Tong UniversityShanghai200240China Department of Mechanical Engineering National Fertilizer Corporation(NFC)Institute of Engineering and TechnologyMultan61000Pakistan The School of Information Science and Engineering Xiamen UniversityXiamen361005China

Structural health monitoring(SHM)is considered an effective approach to analyze the efficient working of several mechanical components.For this purpose,ultrasonic guided waves can cover long-distance and assess large infrastructures in just a single test using a small number of transducers.However,the working of the SHM mechanism can be affected by some sources of variations(i.e.,environmental).To improve the final results of ultrasonic guided wave inspections,it is necessary to highlight and attenuate these environmental variations.The loading parameters,temperature and humidity have been recognized as the core environmental sources of variations that affect the SHM sensing mechanism.Environmental temperature has the most significant influence on SHM results.There is still a need for extensive research to develop such a damage inspection approach that should be insensitive to environmental temperature variations.In this framework,the current research study will not only illuminate the effect of environmental temperature through different intelligent approaches but also suggest the standard mechanism to attenuate it in actual ultrasonic guided wave based SHM.Hence,the work presented in this article addresses one of the open research challenges that are the identification of the effect of environmental and operating conditions in practical applications of ultrasonic guided waves and impedance-based SHM.

关键词： Structural health monitoring ultrasonic guided waves environmental and operating conditions thermal sensitivity

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