For bearing condition monitoring, commonly used measuring points on the casing suffer from low signal-to-noise ratios and strong interference. These issues are expected to be addressed through embedded wireless sensors. To tackle the challenges faced by wireless sensor nodes in terms of energy supply and to enhance their intelligence level, this paper proposes a self-powered smart bearing pedestal

Instruments used for micro-nano observation, often have optical components with lifespans spanning several decades. While piezo inertial actuators offer the benefit of a compact structure, their limited travel life due to frictional wear poses a challenge for adapting to such applications. Currently, direct-drive piezo and electromagnetic hybrid drives are the preferred commercial solutions; however

The objective of this study is to investigate actuations based on the continuum deformation of flexible curved magnetically impregnated pipes conveying fluid. This flexible actuation due to flow-induced and magnetic forces offers a novel perspective in direct-ink-writing (DIW). The motion of the pipe’s tip-ends can be seen as a pen freely writing on paper. A kind of soft material, namely hard-magnetic

This study experimentally evaluates the lifetime of PTFE coating on Inconel-X750 specimens, a material commonly used in gas foil bearings (GFBs), based on surface roughness using a reciprocating test apparatus from a tribological perspective. The primary objective is to verify the enhancement of coating lifetime for GFBs, specifically focusing on the top foil coatings employing solid lubricants. The

This article investigates the sources of uncertainty in the dynamic response of turbine blades equipped with under-platform dampers (UPDs). While UPDs play a critical role in energy dissipation and vibration control, their effectiveness is influenced by various uncertainty factors, including contact pressure distribution, manufacturing variability, wear, loading history and many others. Among these

The usage of an electrical propulsion energy system brings not only a wide speed range and large diving depth to the underwater vehicle but also the new electromechanical features of the PSS (Propulsion Shaft System). Revelation of the electromechanical coupling mechanisms and vibration characteristics is the key to the vibration suppression of PSS. This work presents a reinforced electromechanical

Surrogate models are extensively employed for forward and inverse uncertainty quantification in complex, computation-intensive engineering problems. Nonetheless, constructing high-accuracy surrogate models for complex dynamical systems with limited training samples continues to be a challenge, as capturing the variability in high-dimensional dynamical system responses with a small training set is inherently

Unsupervised Domain Adaptation (UDA) has achieved tremendous success in the task of solving new unlabeled target domains by leveraging its knowledge learned from labeled source datasets and has been widely utilized in wind turbine fault diagnosis. However, in the actual industrial scenarios, data privacy, commercial confidentiality, and transmission efficiency constraints make the source domain data

In this paper, the low-frequency flexural wave band gap and broadband vibration reduction characteristics of multi-scale elastic metabeams with particle damping are theoretically and numerically studied. A band gap theoretical prediction model of multi-scale elastic metabeams with particle damping is established by using the plane wave expansion method combination with the gas-particle two-phase flow

Metastructures with periodically arranged high-static-low-dynamic stiffness (HSLDs) resonators can generate low frequency bandgap, thereby they are widely applied in low-frequency vibration suppression. However, the width of the bandgap decreases as the bandgap shifts to low frequency, severely reducing the robustness of the metastructure in frequency detuning. In this study, unit cells that consist

Microjet technology can realize tiny droplet spraying, with the prospect of replacing the traditional process, so it has been widely researched and applied. Existing single nozzles have essentially fixed orifice diameters. If different size droplets are to be obtained, this is done by increasing the voltage, stacking multiple droplets to replace the nozzle, and so on. However, by these ways will bring

This study introduces a novel homotopy-based semi-analytical approach designed to tackle challenges posed by strong nonlinear frequency mixing effects and mixed periodicity and quasi-periodicity intervals, which remain unsolved in the literature. This method, termed the iterative residue-regulating homotopy method (IRRHM), starting from a simple initial guess, seeks to achieve an asymptotic convergence

Fastening clips, though seemingly minor components, are crucial for maintaining the stability and smoothness of railway tracks. However, clip fatigue fractures have been frequently encountered in high-speed railways due to high-frequency excitations. This study develops an efficient predictive model for clip fatigue life assessment using a particle swarm optimization algorithm (PSOA). Firstly, the

In practical applications, a large number of current research efforts regarding overhead crane systems tend to overly simplify them by adopting a single pendulum-element point model. Nevertheless, this paper puts forward a three-dimensional (3-D) model for the overhead crane with a distributed mass load, which conforms more closely to the actual engineering requirements in the real world. To cope with

Frequency-domain performance analysis of intersample behavior in sampled-data and multirate systems is challenging due to the lack of a frequency-separation principle, and systematic identification techniques are lacking. The aim of this paper is to develop an efficient technique for identifying the full intersample performance in the frequency-domain for closed-loop multirate systems, in particular

Ambient environment abounds with renewable low frequency vibration energy, but efficiently harnessing this energy remains challenging due to its low-grade nature. Herein, we propose a vibration energy modulator (VEM) to solve this issue through an innovative automatic energy accumulation-discharge (AEAD) strategy. The VEM is realized through the integration of a distinctive energy modulation unit within

Accurate identifying moving load is of great significance for bridge design, operation and maintenance. As the condition state of actual bridges is complex, moving load is subjected to time-varying uncertainty. Traditional probability theory uses stochastic process to describe uncertain moving load time history, which relies on plenty of samples. This paper proposes a bridge moving load identification

Direct numerical simulations of mechanical metamaterials are often computationally prohibitive due to multi-scale geometric complexity. This work develops a non-locality homogenization method (NLHM) integrating multi-scale asymptotic homogenization with generalized finite element principles for static and dynamic analysis. The method converts heterogeneous materials with inclusions or voids into mechanically

Nonlinear guided wave-based Structural Health Monitoring (SHM) systems provide a powerful approach for the accurate detection and localization of structural damage by using harmonic generation as a key indicator of anomalies. However, distinguishing structural harmonics from those induced by instrumentation, particularly piezoelectric (PZT) actuators, remains a significant challenge. Over time, PZT

Topological phononic crystals (PCs) as a novel and hot research of topological phases of matter have attracted increasing attention due to the topological transport characteristics of elastic waves. However, the effectively multi-field realization and regulation of elastic waves topological transport in complex environments remains a challenge. This study designs a novel magnetostrictive PC plate composed

Edge preparation enhances tool life, cutting process stability, and surface quality. The tool was treated with magnetoelastic abrasives to optimize edge preparation. An orthogonal experiment was conducted to investigate the effects of abrasive grain size, tool speed, preparation time, disk spacing, and disk speed on the edge preparation amount. Milling experiments on TC4 titanium alloy were conducted

Clearance-type nonlinearity is common in engineering structures due to gaps between components, influencing contact states and potentially causing system instability. This paper studies a hierarchical Bayesian probabilistic model for simultaneous model selection and parameter estimation of clearance-type nonlinearity. Utilizing the SINDy framework, interpretable variables such as the clearances, contact

Model updating of engineering systems inevitably involves handling both aleatory and epistemic uncertainties. Addressing these uncertainties poses significant challenges, particularly when data and simulations are limited. This study proposes a novel latent space-based method for stochastic model updating that leverages limited data to effectively quantify uncertainties in engineering applications

The widespread occurrence of slippage resulting from relative sliding between rolling elements and raceways within rolling bearings poses a significant risk to their internal heating and lifespan, previous research has predominantly focused on the overall slip behavior of the bearing’s internal cage, with relatively little attention given to the local slip behavior of the rolling elements inside the

Monte Carlo-based methods are widely applied in reliability analysis of wind-excited structures, but require input from numerous realizations of stochastic wind loads or fields. Such realizations must preserve consistent second-order properties, including variance and power spectral density (PSD). Numerical simulation is a common substitute for repeating thousands of prohibitively expensive wind tunnel

Time-variant secondary paths can significantly degrade the vibration suppression performance of active vibration control systems that rely on offline-modeled secondary paths. To address this issue, the mirror-modified filtered-x least mean square (MMFxLMS) algorithm has been proposed. However, the MMFxLMS algorithm suffers from multiple solutions to the modeling equations in the overall modeling part

Pressure record processing is a powerful tool for research and diagnosis of internal combustion engines. From the pressure record, using the energy conservation equation, it is possible to calculate the rate of heat release (RoHR) and thus quantify the evolution of the combustion process. In order to obtain accurate RoHR results, it is necessary to remove as much noise as possible from the pressure

This study investigates the impact of similarity bias in machine learning research focused on vibration data for intelligent fault diagnosis. Conducting experiments on publicly available vibration datasets, the research compares performance between conventional and deep learning models under a cross-validation strategy, addressing the similarity bias issue. Three classification models are employed

To solve the problem of rotary dynamic seals that are prone to failure at high speeds, oil-immersed wet motors are used in motor pumps. The resulting long-term erosive wear and deterioration of the winding insulation layer seriously affects the operational reliability of the motor. This paper presents a wet external rotor permanent magnet brushless DC (WER-PMBLDC) motor with an isolation sleeve separating

The tire-road friction coefficient (TRFC) plays a crucial role in vehicle stability, active safety control, and autonomous driving systems. This paper proposes a novel method to estimate the TRFC using accelerometer-based intelligent tires and tire dynamics. Firstly, an intelligent tire finite element model equipped with several accelerometers is established and its accuracy is verified through experiments

Bowel cancer is the second leading cause of cancer-related deaths worldwide, underscoring the critical need for accurate staging. Various methods and tools are being developed to improve the precision and efficiency of bowel cancer diagnoses. This paper studies the development of an indentation probe to measure the mechanical properties of bowel cancer through dynamic analysis. A genetic algorithm

Flexure couplings are alternatives to conventional mechanical joints, eliminating tribological effects and joint reversal uncertainties. However, their low stiffness-induced dynamic errors hinder utilisation in high precision applications. Additionally, during operation flexure couplings can experience large deflections, leading to significant changes in their dynamic behaviour. An effective vibration

Conventional rolling bearing fault signal decomposition methods often suffer from at least some of the following problems: algorithms lacking adaptability and anti-noise performance, components lacking physical significance, or difficulty in achieving modal alignment when analyzing multichannel signals. Aiming at these problems, this paper takes advantage of the strong adaptability and robustness of

This study explores the low-frequency nonlinear vibration control of a semi-active system based on the dielectric elastomers (DEs). The incremental harmonic balance method (IHBM) combined with the arc-length continuation method is employed to analyze the nonlinear dynamic behaviors and vibration control of the system. The results reveal a series of novel nonlinear dynamic phenomena, including isolated

Accurate prediction of performance degradation trends is crucial for aero-engine maintenance strategies. Most existing studies assume that data collected under a limited set of operating conditions, or that sufficient non-degraded data are available. Furthermore, these studies typically provide only future performance reference points without accounting for maintenance recovery. During an aero-engine’s

Flexible barrier systems play a crucial role in rockfall hazard mitigation due to their exceptional energy dissipation capabilities. While deformation patterns of flexible barrier systems during rockfall impacts constitute data for post-event structural assessment and emergency response planning, traditional contact sensor-based approaches face significant limitations in installation complexity and

To further explore the beneficial effects of vehicle ISD (inerter-spring-damper) suspension, an optimal design approach grounded in the fractional-order SH-GH (skyhook-groundhook hybrid) control strategy is put forward in this paper. First, by incorporating fractional-order theory, the ideal SH-GH ISD suspension structure, comprising both integer-order and fractional-order elements, is derived. After

This paper considers the kernel design for impulse response estimation of resonant systems, exemplified through a vehicle suspension system. The identification of resonant systems is highly challenging due to their long impulse responses and dynamics that may be close to the limit of stability. These issues have not been investigated in the existing literature on kernel design. A novel incremental

The folding fin, essential for controlling aircraft flight attitude and maintaining stability, is extensively employed in aerospace vehicles. Inevitable freeplay within the structure, due to design, installation, and mechanical wear, reduce the stiffness of the folding fins and impair the aircraft’s aerodynamic performance. Therefore, eliminating the freeplay in the folding fin is crucial for enhancing

Magnetorheological elastomers (MREs) have attracted considerable attention due to their adaptive stiffness and damping properties, which make them highly effective for vibration isolation applications. Despite recent advancements in MRE isolation technology, significant challenges persist in accurately modeling the inverse nonlinear dynamics of MRE isolator. This paper proposes a novel CBi-AM model

Multi-component structures, which are extensively utilized in aviation, automotive industries, and other fields, may generate significant noise or even lead to failure due to abnormal vibrations within excitation frequency ranges if improperly designed. Research on structural optimization addressing this issue remains limited, with most studies relying on density-based topological optimization methods

The cutting mechanism and regenerative vibration in machining workpieces have been widely discussed. However, there remains a lack of precise understanding regarding how machine tool dynamics affect machining accuracy, especially at the theoretical level. In response, this work establishes a dynamic motion error model jointly controlled by machine tool structural vibration, screw shaft non-ideal rotation

Nonlinear dynamic interfaces, such as bearings, splines, and gears, play important roles in mechanical systems. During the operation of gearbox transmission systems, vibration signals and power are attenuated and dissipated by friction, damping, and other nonlinear factors present in various dynamic interfaces. This paper focuses on quantifying the influence of nonlinear factors on vibration signal

Stay cables are essential components of cable-stayed bridges, and accurate cable force identification is crucial for structural health assessment. However, traditional cable force measuring solutions have inevitably disadvantages, such as limited applicability, low efficiency, and numerous factors affecting accuracy. To address this, a fusion framework for cable force identification is proposed, integrating

This investigation is devoted to an in-depth analysis of the flutter boundary and free vibration characteristics exhibited by a laminated fiber-reinforced magnetorheological elastomer (Fiber-MRE) circular and annular plate. Experimental endeavors are directed towards the extraction of the viscoelastic properties inherent in the MRE substrate. Utilizing the Generalized Maxwell model in conjunction with

Blade fracture is one of the most difficult faults to diagnose in rotating machinery. Most gas turbines can only measure casing vibration rather than directly measuring blade vibration with other sensors, making monitoring and diagnosing such faults more challenging. Research on vibration characteristics and fault diagnosis methods of blade fracture is critical to ensure the safe and reliable operation

Current research on anomaly detection in industrial environments has advanced significantly in single robot systems but faces challenges with large-scale, regionally distributed robot clusters. These systems contend with complex inter-machine interactions and regional dynamics, as well as distinct differences in robot data characteristics, limiting the effectiveness of existing methods in terms of

The thermal and dynamic characteristics of the sliding guide system in CNC machine tools are critical factors influencing machining accuracy and operational stability. Nevertheless, conventional thermal or dynamic analyses in isolation are insufficient to elucidate the influence of thermal-dynamic coupling on the overall performance of the system. In this paper, based on the thermal-dynamic interaction

The ring periodic structures (RPSs) are normally subjected to external forces in practice. In contrast to previous studies on how the external forces affect the forced vibration, this work examines the effects of the external forces on the natural frequency splitting. The studied RPS consists of a thin ring subjected to external forces and stiffnesses, which are uniformly distributed along its inner

This paper presents a numerical approach for evaluating the performance and the micromotions of the rotors in a Gerotor unit, accompanied by an extensive experimental activity aimed at validating this approach. The simulation model begins with a geometrical module that preprocesses the CAD drawings of a given unit. The model then performs a fluid dynamic analysis using a lumped-parameter formulation

Blade-casing rubbing impact is a prevalent failure mode in aeroengine rotor systems. This study presents a real-time coupled model for the dual-rotor-bearing system, aimed at investigating the vibration transmission and behavior interference between system components. In this model, dedicated methods are developed to characterize the flexible components and the rubbing-impact phenomena, while the real-time

High-static-low-dynamic stiffness (HSLDS) isolators based on negative stiffness mechanisms (NSMs) have been used widely for low-frequency vibration isolation. However, most existing NSMs are not adjustable and have nonlinear properties, which limits the isolation performance to some extent. This paper proposes an electromagnetic mechanism (EM) with a new magnetic circuit design and coil configuration

Deterioration prognosis of rolling bearings is of significance for remaining useful life (RUL) estimation and predictive maintenance of mechanical systems. However, the extreme nonlinearity, fluctuations and jump outliers of the degradation process with leptokurtosis and fat-tail distribution cannot be accurately captured by conventional physics-based and data-driven models. To alleviate this bottleneck

Bending-torsional coupling of unbalanced rotor may lead to combined resonance or dynamic instability in rotor systems, potentially compromising system operation. Existing studies on bending-torsional coupling often rely on rotor models that consider only lateral and torsional vibrations, neglecting the influence of pitch vibration and gyroscopic effect in flexible rotors. For this reason, the present

An energy-based analysis for the self-synchronization of two unbalanced rotors installed in a two-DOF platform, a vibrating system with translational degrees of freedom, was performed to examine the effects of anisotropy in the vibration properties of the platform and the relative rotational directions of the rotors. Based on two conditional energy equations that were extended in the present study

Video-based vibration modal identification is an emerging technique for structural dynamics characteristics measurement. However, identifying physical modes typically requires extensive manual spectral interpretation by experts, or the over-estimation of candidate modes. As a result, automatic and efficient modal determination remains challenging when dealing with mode-mixed video data that contains

Bistable energy harvesters (BEH) have been widely investigated for their wide operation bandwidth and high energy conversion efficiency. Since the output voltage of the BEH is alternative current (AC) and not direct current (DC), an electrical interface is required to convert AC to DC. Recently, the nonlinear treatment of the voltage on the piezoelectric element has been validated to greatly enhance

Inerters with mass amplification and negative stiffness devices featuring high static-low dynamic stiffness significantly enhance the control effect of traditional tuned mass dampers (TMDs) on structural vibrations. However, limited research has integrated these systems within wind tunnel tests. This study establishes a theoretical model for a tuned inerter viscous damper with negative stiffness (NS-TIVD)

In industrial manufacturing scenarios, tool wear directly impacts product quality, production efficiency, and machine reliability. However, the deployment of traditional tool condition monitoring (TCM) solutions is hindered by their reliance on invasive, costly sensors and complex configurations. This study presents an innovative, industry-oriented multi-sensor TCM framework that integrates mechanism-based

The application of Frequency Response Function (FRF)-driven Bayesian model updating to Finite Element (FE) model of real structures, particularly building structures, faces three primary challenges: inconsistent inference outcomes across various updating schemes, complexities arising from non-ideal boundary conditions, and the detrimental effects of significant measurement noise. To address these issues