Mechanical Systems and Signal Processing最新文献

{"title":"Modelling and experimental validation of hysteresis loops in bolted joints","authors":"Hassan Jalali,&nbsp;Dylan J. Brown,&nbsp;Hamed Farokhi","doi":"10.1016/j.ymssp.2025.113375","DOIUrl":"10.1016/j.ymssp.2025.113375","url":null,"abstract":"<div><div>Frictional contact interfaces in bolted joints affect the overall structural dynamic properties and can be characterised using key features such as frequency response curves and hysteresis loops. Various hysteresis models, including LuGre, Valanis, and Bouc-Wen, have been employed to simulate the nonlinear behaviour in the tangential direction. In these models, the friction force is determined by solving a nonlinear differential equation numerically. Typically, obtaining an analytical solution for this equation is impractical, and no closed-form solution for the friction force is available, which causes difficulties in the identification of the model parameters using experimental results. In this paper, closed-form solutions for the friction force under general input is obtained and identified using both simulated and experimental results. An experimental test structure is designed, which allows pure excitation of the contact interface in the tangential direction of the joint contact interface. A 3-degree-of-freedom nonlinear reduced-order model is developed for the test structure, which is useful in joint contact interface characterisation. It is shown that at frequencies near the natural frequency, the relative displacement at the contact interface increases, leading to greater energy dissipation. Moreover, the accuracy of the base linear model- used as the foundation for developing the nonlinear reduced-order model- is crucial for reliably identifying the nonlinear parameters of the joint contact interface.</div></div>","PeriodicalId":51124,"journal":{"name":"Mechanical Systems and Signal Processing","volume":"240 ","pages":"Article 113375"},"PeriodicalIF":8.9,"publicationDate":"2025-09-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145222249","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"DiffectNet: diffusion-enabled conditional target generation of internal defects in ultrasonic non-destructive testing","authors":"Dongwon Lee ,&nbsp;Hyung Jin Lee ,&nbsp;Choon-Su Park ,&nbsp;Sooyoung Lee","doi":"10.1016/j.ymssp.2025.113454","DOIUrl":"10.1016/j.ymssp.2025.113454","url":null,"abstract":"<div><div>Ultrasonic testing has been widely adopted as a non-destructive evalua- tion technique for detecting defect-related anomalies across various indus- trial fields. While several previous deep learning-based studies have shown promising results in addressing the inherent limitations of ultrasonic non- destructive testing, a critical challenge remains in acquiring diverse and large- scale datasets, hindering both detection performance and generalization. In this study, we propose a deep learning approach to generate synthetic defect cases tailored to phased array ultrasonic testing (PAUT) systems. Specifi- cally, we introduce a DiffectNet, a diffusion-enabled conditional target gen- eration network that can produce high-fidelity and defect-aware ultrasonic images. Both qualitative and quantitative evaluations demonstrate the su- perior generative performance of the proposed approach compared to exist- ing methods, achieving a 77% improvement in Fŕechet inception distance, a 98% improvement in kernel inception distance, and a 26% improvement learned perceptual image patch similarity error, respectively. Furthermore, we highlight the potential advantage of our approach as a neural augmenta- tion method, which can enhance model performance and generalizability for unseen defect scenarios. This study offers a promising solution to the practical challenge of limited data availability and further contributes to advancing data-driven ultrasonic non-destructive testing methods.</div></div>","PeriodicalId":51124,"journal":{"name":"Mechanical Systems and Signal Processing","volume":"240 ","pages":"Article 113454"},"PeriodicalIF":8.9,"publicationDate":"2025-09-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145222358","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Constant-Force kirigami for scalable, shiftable, stair-stepping and static load-bearing quasi-zero-stiffness metamaterials","authors":"Yanqi Yin ,&nbsp;Fanchi Zeng ,&nbsp;Yang Yu ,&nbsp;Jinyao Zhang ,&nbsp;Ruiyu Bai ,&nbsp;Jiaqiang Yao ,&nbsp;Alexey S. Fomin ,&nbsp;Chao Tang ,&nbsp;Bo Li","doi":"10.1016/j.ymssp.2025.113433","DOIUrl":"10.1016/j.ymssp.2025.113433","url":null,"abstract":"<div><div>Quasi-zero-stiffness (QZS) metamaterials, especially those with multiple plateau characteristic, play an important role in vibration attenuation and isolation systems. However, existing design strategies of QZS metamaterials are limited in the programmability of multi-plateau, that its each stair cannot be tailored either arbitrarily or independently. In this study, a new class of QZS metamaterials is proposed by architecting kirigami cells who embodies kinematic limb-singularity principle in mechanisms. Constant-force behavior, with capability of scalable restoring force and shiftable equilibrium position, is revealed in the cells that unified into one specific kirigami cut topology only. Thus, when stacking a family of monolithic cells into QZS metamaterial, stair-stepping performance is unveiled with each plateau being programmed independently by shifting and scaling each corresponding cell. Theoretical model, combined with simulation analysis and experiments verify the multi-plateau QZS characteristics and vibration isolation with static load-bearing capability. This design strategy, from kinematic perspective, offers new programming tool for QZS metamaterials towards customized mechanical response, instability-free kinematics, and structure compactness.</div></div>","PeriodicalId":51124,"journal":{"name":"Mechanical Systems and Signal Processing","volume":"240 ","pages":"Article 113433"},"PeriodicalIF":8.9,"publicationDate":"2025-09-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145222188","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Virtual sensor grids for full-field vibration measurement via superpixel segmentation and phase-based optical flow","authors":"Yeseul Kong,&nbsp;Seunghwan Lee,&nbsp;Seo Hyeon Jeong,&nbsp;Gyuhae Park","doi":"10.1016/j.ymssp.2025.113414","DOIUrl":"10.1016/j.ymssp.2025.113414","url":null,"abstract":"<div><div>This study presents a novel vision-based approach for high-resolution structural vibration measurement by integrating phase-based full-field motion estimation with virtual sensor grids defined through vibration-guided superpixel segmentation. To overcome the noise sensitivity and instability associated with conventional pixel-level methods, we introduce virtual sensor grids, which cluster spatially and dynamically coherent regions within video data. This strategy enables interpretable and noise-resilient vibration analysis. Within each virtual sensor unit, we perform confidence-weighted spatial aggregation based on a pixel-wise confidence metric derived from phase nonlinearity, resulting in robust and accurate displacement estimation. Experimental validation on an air compressor system demonstrates that the proposed method achieves displacement accuracy comparable to that of a laser Doppler vibrometer (LDV) and facilitates effective structural damage detection without the need for speckle patterns or physical markers. These results confirm the method’s suitability for structural diagnostics, particularly in environments where sensor or marker placement is challenging or where long-term, non-intrusive monitoring is required.</div></div>","PeriodicalId":51124,"journal":{"name":"Mechanical Systems and Signal Processing","volume":"240 ","pages":"Article 113414"},"PeriodicalIF":8.9,"publicationDate":"2025-09-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145222191","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Computationally efficient UAV fault diagnosis with adaptive vibration denoising: A signal processing approach for rotorcraft systems","authors":"Yuchen He ,&nbsp;Husheng Fang ,&nbsp;Jun Yan ,&nbsp;Chengsong Yang ,&nbsp;Yi Zhai","doi":"10.1016/j.ymssp.2025.113413","DOIUrl":"10.1016/j.ymssp.2025.113413","url":null,"abstract":"<div><div>Reliable diagnosis of incipient faults in unmanned aerial vehicles (UAVs) requires denoising methods capable of suppressing mixed noise while preserving short-duration, low-SNR fault signatures. This study presents an Adaptive Dual-Tree Complex Wavelet Transform (ADTCWT) with optimized thresholds via K-means Crowding Differentiated Creative Search (KCDCS), coupled with a Dynamic Attention-Weighted Gradient Boosting Ensemble (DAW-GBE) for fault classification. Validation employed the ICUAS-2023 UAV Fault Diagnosis (UAV-FD) benchmark under Gaussian–impulsive noise, and a DJI Phantom 4 Pro dataset with induced motor looseness, blade damage, and foreign-object debris imbalance. On UAV-FD, ADTCWT surpassed baseline DTCWT, a literature wavelet, and improved SVD + VMD, yielding SNR 16.30 dB, PSNR 20.68 dB, and correlation 0.9548 under 10 % fault severity. Time–frequency analysis confirmed the concentration of fault energy in 50–500  Hz, without introducing spurious components. On DJI data (100  Hz sampling), ADTCWT increased SNR from − 4.25 dB to 23.92 dB, achieved correlation 0.997 with MAE 0.023, and maintained stability across − 6.0 to + 6.0 dB input SNR. KCDCS converged within 40 iterations at 0.032  s/iteration. With ADTCWT preprocessing, DAW-GBE attained 96.1 % accuracy, reduced misclassification between blade damage and looseness by 10.8 %, and reached AUC 0.998. All performance gains were statistically significant at p &lt; 0.01, underlining the framework’s suitability for reliable, on-board UAV health monitoring.</div></div>","PeriodicalId":51124,"journal":{"name":"Mechanical Systems and Signal Processing","volume":"240 ","pages":"Article 113413"},"PeriodicalIF":8.9,"publicationDate":"2025-09-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145222248","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Frequency pattern graph spectrum model and its applications in rolling bearing fault diagnosis","authors":"Yanlei Liu ,&nbsp;Yonggang Xu ,&nbsp;Miaorui Yang ,&nbsp;Hong Jiang ,&nbsp;Kun Zhang","doi":"10.1016/j.ymssp.2025.113426","DOIUrl":"10.1016/j.ymssp.2025.113426","url":null,"abstract":"<div><div>Complicated working conditions and environments will intensify noise and interference in the vibration signal of the bearing, resulting in the submersion of the fault features. To enhance the weak fault information in the original signal, this paper proposes a Frequency Pattern Graph Spectrum Model (FPGS Model). The eigenvalue sequence, which concentrates the data with periodic pulse characteristics in the high order spectral band, is obtained by building the Laplacian matrix from the Fourier transform amplitude spectrum. Extracting key point based on eigenvalue sequences can refine the frequency pattern graph spectrum and reduce the computational complexity. Harmonic correlation index and sliding window are designed to mark fault features in the frequency pattern graph spectrum. This research created a collection of simulated signals to confirm the viability of the proposed method. The method was used on the bearing inner and outer ring experimental signals, and its efficacy was confirmed by contrasting it with other techniques.</div></div>","PeriodicalId":51124,"journal":{"name":"Mechanical Systems and Signal Processing","volume":"240 ","pages":"Article 113426"},"PeriodicalIF":8.9,"publicationDate":"2025-09-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145222356","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Mechanical in-sensor computing: A programmable meta-sensor for structural damage classification without external electronic power","authors":"Tingpeng Zhang ,&nbsp;Xuzhang Peng ,&nbsp;Mingyuan Zhou ,&nbsp;Guobiao Hu ,&nbsp;Zhilu Lai","doi":"10.1016/j.ymssp.2025.113347","DOIUrl":"10.1016/j.ymssp.2025.113347","url":null,"abstract":"<div><div>Structural health monitoring (SHM) typically involves sensor deployment, data acquisition, and data interpretation, commonly implemented via a tedious wired system. The information processing in current practice majorly depends on electronic computers, albeit with universal applications, posing challenges such as high energy consumption and low throughput due to the nature of digital units. In recent years, there has been a renaissance interest in shifting computations from electronic computing units (e.g., Graphics Processing Unit) to the use of real physical systems, a concept known as <em>physical computation</em>. This approach provides the possibility of thinking out of the box for SHM, seamlessly integrating sensing and computing into a pure-physical entity, without relying on external electronic power supplies, thereby properly coping with resource-restricted scenarios. The latest advances of metamaterials (MM) hold great promise for this proactive idea. In this paper, we introduce a metamaterial-based sensor (termed as <em>MM-sensor</em>) for physically processing structural vibration information to perform designated SHM tasks, such as structural damage warning (binary classification). The decision boundary of the binary classification is programmable via a proposed inverse design framework. The MM-senosr minimizes the need for further information processing or resource-consuming operations by enabling in-situ data acquisition and analysis directly at the sensing node. We adopt the configuration of a locally resonant metamaterial plate (LRMP) to achieve the first fabrication of the MM-sensor. We take advantage of the bandgap properties of LRMP to physically differentiate the dynamic behavior of structures before and after damage. By inversely designing the geometric parameters, our current approach allows for adjustments to the bandgap features. This is particularly effective for engineering systems with a first natural frequency ranging from 9.54 Hz to 81.86 Hz; a wider range can be achieved with extended design choices. Both simulations and laboratory experiments were conducted to validate the applicability of the proposed MM-sensor, with a binary damage classification metric of over 93% through a purely physical mechanism. This success demonstrates the realization of mechanical in-sensor computing for SHM.</div></div>","PeriodicalId":51124,"journal":{"name":"Mechanical Systems and Signal Processing","volume":"240 ","pages":"Article 113347"},"PeriodicalIF":8.9,"publicationDate":"2025-09-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145182930","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"An unsupervised denoising via differential feature learning under high-level noise indistinguishable from defect edges","authors":"Erqing Zhang ,&nbsp;Shaofeng Wang ,&nbsp;Jianhua Du ,&nbsp;Luncai Zhou ,&nbsp;Yongquan Han ,&nbsp;Wenjing Liu ,&nbsp;Jun Hong","doi":"10.1016/j.ymssp.2025.113420","DOIUrl":"10.1016/j.ymssp.2025.113420","url":null,"abstract":"<div><div>In industrial inspection scenarios, the superposition of multiple acoustic sources and the nonlinear, time-varying characteristics of noise significantly complicate the direct characterization of defects from raw detection signals. In the absence of accessible paired training data, a critical challenge lies in simultaneously suppressing noise while maximally preserving salient signals and recovering defect features obscured by high-level noise. To address this, An unsupervised denoising network is proposed, incorporating two principal innovations. First, to achieve both high-level noise suppression and the recovery of noise-obscured defect regions, a generator architecture based on a degradation-decoupling mechanism is designed. A decoupled attention module is proposed to enhance the separability among defect bodies, noise-masked defect areas, and high-noise backgrounds. By leveraging their complementary structural features, more accurate reconstruction of complete defect morphology is enabled. Moreover, the high perceptual similarity between defect edges and noise, coupled with the insufficient domain constraints of unsupervised learning, tends to cause structural distortion of defects. To address this issue, A differential feature modeling strategy for regions of interest is proposed to improve the preservation of defect-relevant information in regions of interest. Experimental results demonstrate that the proposed unsupervised denoising network effectively suppresses noise while preserving signals of interest and recovering defect features obscured by interference. Comparative evaluations further validate its superior overall performance over both supervised and unsupervised deep learning-based denoising approaches.</div></div>","PeriodicalId":51124,"journal":{"name":"Mechanical Systems and Signal Processing","volume":"240 ","pages":"Article 113420"},"PeriodicalIF":8.9,"publicationDate":"2025-09-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145222251","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Fixed time trajectory tracking control for Marine crane with anti-saturation input and unmatched disturbances","authors":"Wei Peng ,&nbsp;Yihao Shi ,&nbsp;Menghua Zhang ,&nbsp;Chengdong Li ,&nbsp;Fang Shang ,&nbsp;Zhi Li","doi":"10.1016/j.ymssp.2025.113378","DOIUrl":"10.1016/j.ymssp.2025.113378","url":null,"abstract":"<div><div>Even through the Marine crane have been widely used in maritime logistics, port construction, and military sectors, the precise tracking control should address a lot of challenges, such as the complex external disturbances, the input saturation characteristics and the unknown/unmatched disturbances et al. Therefore, a preset-performance fixed-time control method is proposed considering the anti-saturation input and unmatched disturbances. Firstly, in order to precisely estimate and compensate the unmatched disturbances, a novel fixed time disturbances observer is designed in detail. Then, a fixed time adaptive trajectory tracking controller is designed step-by-step way, by integrating the preset trajectories, the disturbances observer, and the dynamic sliding mode. And, the convergence and stability of the system are analyzed, and the sufficient conditions for uniformly globally fixed-time stability are given based on Lyapunov theory. Finally, both the simulations and hardware experimental are conducted with comparative methods. The experimental results demonstrate that the proposed method substantially enhances operational accuracy and safety in Marine cranes.</div></div>","PeriodicalId":51124,"journal":{"name":"Mechanical Systems and Signal Processing","volume":"240 ","pages":"Article 113378"},"PeriodicalIF":8.9,"publicationDate":"2025-09-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145182902","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Damages of bridge bearings detected from asymmetry of time-varying frequencies measured by a test vehicle","authors":"Z.L. Wang ,&nbsp;L. Chen ,&nbsp;J. Xing ,&nbsp;Z.Y. Liu ,&nbsp;J.X. Huang ,&nbsp;D. Zeng ,&nbsp;Y. Guan ,&nbsp;Y.B. Yang","doi":"10.1016/j.ymssp.2025.113403","DOIUrl":"10.1016/j.ymssp.2025.113403","url":null,"abstract":"<div><div>A novel method is firstly proposed for detecting damages in bridge support bearings from the asymmetry of time-varying frequencies extracted from vehicle responses. Initially, closed-form solutions are derived for the system’s time-varying frequencies, i.e., instantaneous frequencies (IFs), of a vehicle traversing a bridge supported by elastic springs. It is revealed that the bridge’s IFs are strongly correlated with its mode shapes. When the end supports degrade symmetrically, the mode shape remains symmetric; conversely, significant stiffness loss on one side results in pronounced asymmetry. Subsequently, a technique is proposed for damage detection in bridge end supports based on the vehicle response, which comprises three steps: (1) vehicle acceleration responses are collected using a single onboard accelerometer, and the bridge’s IFs are extracted via the Synchroextracting Transform (SET); (2) overall stiffness degradation is evaluated using the Average Offset Ratio (AOR) of the extracted IFs; and (3) asymmetric damage is identified by quantifying the spatial asymmetry of IF distributions through the Difference in Shannon Entropy (DSE). Numerical simulations demonstrate that the method effectively detects different support damages and is robust against road roughness and environmental noise. Additionally, model-scale experiments are conducted, and the engineering feasibility of the proposed technique is validated. Owing to its simplicity in equipment requirements, the method enables rapid and cost-effective screening of bridge-end support conditions and offers a new perspective for substructure health monitoring.</div></div>","PeriodicalId":51124,"journal":{"name":"Mechanical Systems and Signal Processing","volume":"240 ","pages":"Article 113403"},"PeriodicalIF":8.9,"publicationDate":"2025-09-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145182926","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}