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The propagation nature of sonic waves in a temperature gradient field is often simplified with uniform temperature assumptions, resulting in compensation errors in ultrasonic-based oil film measurement. Focusing on this, a novel compensation method of inverting the temperature gradient via ultrasonic signal is proposed. For thrust bearings, the time shift of the reflected signal from the substrate-coating

Full-field three-dimensional (3D) displacement measurement is highly sought after for the mechanical design, assessment, and health monitoring of large structures. The emerging microwave displacement measurement technique provides the potential for wide-ranging full-field measurement capabilities; however, it still faces challenges in achieving full-field 3D displacement measurement. In this article

This paper proposes a new passive self-tuning vibration neutraliser, which contains a mass, a spring, a lever, a lever fulcrum and a passively self-tuning device. The mass and spring are connected to the two ends of the lever. The other end of the spring is attached to the primary structure. The effective stiffness and mass are dependent upon the position of the fulcrum, which is self-tuneable passively

The presence of noise or other abnormal points in the measured point clouds of the turbine blade can result in local discontinuities of the tool path curves, fitted by the machining path points generated by slicing the measured point cloud. In addition, the fluctuation exists in the tool orientation vectors corresponding to the cutter-contact (CC) points in the toolpath curves. These issues can lead

Robotic machining and automatic offline programming has been developing rapidly over the last decade, yet the absolute accuracy of industrial robots significantly impacts the processing performance, limiting their application in high-precision manufacturing fields. For dynamic non-contact continuous robotic machining tasks, such as laser cutting, precise trajectory tracking performance is especially

Accurate kinematic parameters are crucial for deploying industrial robots in high-precision manufacturing applications, such as machining workpieces. Traditional kinematic identification methods often assume that nominal parameter values are known and used as initial estimates. However, in industrial applications, obtaining such nominal values is challenging due to the limited access to detailed design

Inspired by the biomechanics of human shoulder and elbow joints, this study proposes a novel 4-DOF human-inspired flexible mechanism (HIFM). The HIFM integrates a dual-mode operational characteristic that combines rigidity and flexibility, with a particular emphasis on its flexible mode, which significantly enhances the safety and stability of capturing non-cooperative targets. First, a dynamic model

Quasi-zero stiffness (QZS), a beneficial nonlinear feature, offers solutions like wide-bandwidth vibration isolation, energy harvesting, and adaptive shape-changing with multi-stability. However, high-end applications require QZS to be miniaturized, demanding compact size, lightweight, high durability, and low complexity. This paper introduces a groundbreaking nonlinear mechanical meta-structure, the

Optimization of systems of damped primary structures with tuned mass dampers (TMDs) remains a challenge for analytical methods to date. Due to the existence of the primary structure damping, the well-known fixed point theory is not directly applicable. This paper deals with this problem. First, it is found that there exist two so-called semi-fixed points of which the abscissas are independent of TMD’s

In this paper, the dynamic responses of a rotor-bearing system with an asymmetric shaft are studied, focusing on the effect of the shaft asymmetry on the dynamic response of the rotor-bearing system. The asymmetric shaft is modeled considering shear effect based on Timoshenko beam theory. Both one-sided and two-sided cuts are considered in the cross-section of the asymmetric shaft. Various positions

To improve the vibration attenuation performance of the all-terrain vehicles (ATVs) equipped with magnetorheological (MR) suspension with parameter uncertainty and time delay in the sensitive frequency band of human body, this study proposed a finite-frequency robust (FFR) H∞ control strategy. Firstly, a MR suspension model with seven degrees of freedom is established. The boundaries of parameter uncertainty

Porous sintered silver is increasingly recognized as a key interconnection material for future high-temperature power device packaging due to its excellent thermal performance and mechanical properties. However, accurately predicting the creep behavior of porous sintered silver remains challenging. To address this, an enhanced FFT-based homogenization method was implemented to efficiently analyze the

Driven by technological advancements and the increasing need for efficiency and customization, the manufacturing industry is shifting towards Shared Manufacturing. This strategy enhances global production flexibility and resource utilization by enabling diverse entities to collaboratively engage in distributed manufacturing activities. Expanded resource sharing across industries and society, along

In order to satisfy the requirements of sustainable manufacturing of artificial implants and reduce the machining difficulty of heterogeneous material, the ultrasonic atomization (UA) methodology with water-based lubricating fluids is integrated into the micro-end-milling operation for manufacturing miniaturized implants of porous titanium. In this paper, an uncertainty-aware machinability-oriented

Metamaterials are renowned for their unique properties, but most have fixed properties once fabricated. Tensegrity metamaterials offer tunable mechanical properties by adjusting prestress, making them excellent for load-bearing and energy absorption. However, tensegrity structures’ inherent self-equilibrium and stability demand complex geometries with irregular angles and pre-tensions, restricting

Tool wear condition monitoring is essential for reducing production costs and improving machining precision, serving as a key strategy for achieving machine tool intelligence. However, existing methods often depend on empirically designed complex networks to achieve high recognition accuracy, which results in high computational costs, poor performance during later wear stages, and limited interpretability

This paper, the first of two companion papers, reports a sensing methodology for synchronous and successive detection of ‘multiple parameters’, via ‘multiple modes’ internal resonance in coupled oscillators.

Guided wavefield imaging is an emerging technique for the nondestructive inspection of plate-type structures. While existing wavefield imaging methods primarily focus on wavenumber analysis, they often overlook the crucial damage information encoded in the spatial wavefield. In contrast to wavenumber analysis methods, this study introduces the Teager-Kaiser energy operator (TKEO) to process guided

Domain adaptation is essential for the intelligent diagnosis of rotating machinery, especially when target domain data is unlabeled. Traditional methods face limitations in feature extraction and distribution discrepancy evaluation. To address these challenges, this work presents a novel adversarial domain adaptation framework, termed unconstrained Wasserstein distance and multi-attention fusion convolutional

Vibration attenuation is a critical aspect of mechanical engineering design, and eddy currents provide an effective damping technique that does not add mass to the system, and it is especially effective at low frequencies. In this context, this paper introduces a methodology tailored for the design of thin non-magnetic metallic beams with eddy current damping. By solving the eddy current problem for

Integrating structural vibration sensors with actuator controllers into aircraft structures to achieve sensor/actuator integration is crucial for enhancing the spatial utilization and safety of aircraft. Flexible piezoelectric composites (FPC) are the most effective materials for combining sensing and actuation. In current studies on vibration measurement, two-dimensional plane models are commonly