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Ultra‑High Sensitivity Anisotropic Piezoelectric Sensors for Structural Health Monitoring and Robotic Perception

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Nano-Micro Letters 2025年第2期17卷 432-446页

作者： Hao Yin Yanting Li Zhiying Tian Qichao Li Chenhui Jiang Enfu Liang Yiping Guo State key laboratory of Metal Matrix Composites School of Materials Science and EngineeringShanghai Jiao Tong UniversityShanghai 200240People’s Republic of China Beijing Vacuum Electronics research Institute Beijing 100015People’s Republic of China Fundamental Science On vibration Shock and Noise LaboratoryState Key Laboratory of Mechanical System and VibrationSchool of Mechanical EngineeringShanghai Jiao Tong UniversityShanghai 200240People’s Republic of China

Monitoring minuscule mechanical signals,both in magnitude and direction,is imperative in many application scenarios,e.g.,structural health monitoring and robotic sensing ***,the piezoelectric sensor struggles to satisfy the requirements for directional recognition due to the limited piezoelectric coefficient matrix,and achieving sensitivity for detecting micrometer-scale deformations is also ***,we develop a vector sensor composed of lead zirconate titanate-electronic grade glass fiber composite filaments with oriented arrangement,capable of detecting minute anisotropic *** as-prepared vector sensor can identify the deformation directions even when subjected to an unprecedented nominal strain of 0.06%,thereby enabling its utility in accurately discerning the 5μm-height wrinkles in thin films and in monitoring human pulse *** ultra-high sensitivity is attributed to the formation of porous ferroelectret and the efficient load transfer efficiency of continuous lead zirconate titanate ***,when integrated with machine learning techniques,the sensor’s capability to recognize multi-signals enables it to differentiate between 10 types of fine textures with 100%*** structural design in piezoelectric devices enables a more comprehensive perception of mechanical stimuli,offering a novel perspective for enhancing recognition accuracy.

关键词： Flexible piezoelectric filaments Anisotropic Ultra-high sensitivity Structural health detection Texture recognition

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Enhancing forecasting of current-carrying performance through spatial frequency analysis of interface morphology

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Science China Technological Sciences 2025年

作者： Nian YIN Zishuai WU Zhangli HOU Yiwei ZHANG Zhinan ZHANG State key laboratory of Mechanical System and vibration Shanghai Jiao Tong University School of Mechanical Engineering Shanghai Jiao Tong University

Electrical contact interfaces, integral to devices such as connectors, switches, and conductive slip rings, play a crucial role in determining current-carrying capabilities. This study adopts spatial frequency analysis to assess the currentcarrying performance of interfaces based on their morphological characteristics. Initially, rough surfaces with various parameters, including the cutoff frequency(N), the spectral index(β), and the gain factor(A), were generated using spatial frequency methods, followed by current-carrying simulations. The findings reveal that the characteristic parameters derived from spatial frequency methods exhibit a significantly stronger correlation with current-carrying performance than traditional roughness metrics. To enhance the practical applicability of this research, a physical-informed machine learning approach for rough surface features extraction was developed, demonstrating high predictive parameter identification accuracy for the three parameters. Overall, this paper introduces a tribo-informatics approach for analyzing and extracting rough surface features that considers the curvature characteristics of contact points. This approach holds significant potential for evaluating the processing state of current-carrying interfaces, selecting high-quality surfaces, and forecasting current-carrying performances.

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Modeling tactile perceived intensity for vibration from a coin eccentric rotating mass motor

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Science China Technological Sciences 2025年

作者： Yun FANG Jingchen HUANG Yujun WU Jiaqi DONG Weichao GUO Xinjun SHENG State key laboratory of Mechanical System and vibration School of Mechanical Engineering Shanghai Jiao Tong University Meta Robotics Institute Shanghai Jiao Tong University

Establishing the relationship between vibrotactile parameters and perceived intensity（PI） is of great significance in the regulation of desired sensations, which contribute to haptic interfaces in practical applications. Coin eccentric rotating mass（ERM） motors are routinely utilized due to their lightweight design and efficient ability to evoke strong tactile sensations. By adjusting input voltages, ERMs can yield different stimuli, but the effects of their physical properties on PI remain ***, we developed the physical model of the ERM-skin system and optimized the parameters affecting PI. Moreover, the relationship between stimulus and perception was derived based on Fechner?s law. Three experiments were conducted on fifteen subjects（ten males and five females, aged 24.40 ± 2.87 years） to identify the vibration parameters and corresponding PI to verify the proposed PI model. ERMs in this study were attached to phantom skin/forearm with slim adhesive tape to minimize the interference. Experiment 1 performed vibration calibration with ERM attached to the skin phantom to simulate the actual configuration. Then, the relative and absolute PI of subjects on specific stimuli were acquired in Experiments 2 and *** fitting reliability of the proposed PI model was evaluated on fifteen subjects with R2of 0.73 ± 0.07 and root mean squared error（RMSE） of 1.35 ± 0.28. Overall, the proposed PI model established the quantitative relationship between stimulus parameters（vibration parameters and physical parameters） and subjective PI, which provided theoretical support for ERM optimization and vibrotactile modulation.

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A Simple and Accurate Method for Calculating the Gaussian Beam Expansion Coefficients

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Chinese Physics Letters 2010年第12期27卷 105-108页

作者：刘伟杨军 The State key laboratory of Acoustics and the key laboratory of noise and vibration research Institute of Acoustics Chinese Academy of Sciences Beijing 100190

The calculation of the diffraction field radiated from the ultrasonic transducer can be simplified by using the Gaussian beam expansion technique. The key problem of this technique is how to determine the coefficients of Gaussian functions. We present a simple and accurate optimization method to calculate the Gaussian beam expansion coefficients, Half of the coefficients are obtained by solving linear equations. The other half are derived from the Fourier series expansion. Wave field simulation results demonstrate the validity of the new method.

关键词： Mathematical physics

Experimental measurement of tip vortex flow field with/without cavitation in an elliptic hydrofoil

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Journal of Hydrodynamics 2017年第6期29卷 939-953页

作者：彭晓星徐良浩刘玉文张国平曹彦涛洪方文颜开 National key laboratory on Ship vibration and noise China Ship Scientific Research CenterWuxi 214082China

In this paper, recent measurements of tip vortex flow with and without cavitation carried out in Cavitation Mechanism Tunnel of China Ship Scientific research Center（CSSRC） are presented. The elliptic hydrofoil with section NACA 662-415 was adopted as test model. High-speed video（HSV） camera was used to visualize the trajectory of tip vortex core and the form of tip vortex cavitation（TVC） in different cavitation situations. Laser Doppler velocimetry（LDV） was employed to measure the tip vortex flow field in some typical sections along the vortex trajectory with the case of cavitation free. Stereo particle image velocimetry（SPIV） system was used to measure the velocity and vorticity distributions with and without cavitation. Series measurement results such as velocity and vorticity distributions, the trajectory of tip vortex core, the vortex core radius, cavity size and cavitation inception number were obtained. The results demonstrated that the minimum pressure coefficient in the vortex core obtained by flow field measurement was quite coincident with the tip vortex cavitation inception number obtained under the condition of high incoming velocity and low air content. And TVC would decrease the vortex strength comparing with the case without cavitation.

关键词： Tip vortex flow field cavitation LDV SPIV HSV measurement data

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An Adaptive Time-Domain Kalman Filtering Approach to Acoustic Feedback Cancellation for Hearing Aids

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Chinese Journal of Electronics 2020年第1期29卷 139-146页

作者： LU Caixia YANG Feiran YANG Jun key laboratory of noise and vibration research Institute of Acoustics of Chinese Academy of Science University of Chinese Academy of Science

The adaptive filtering approach has been widely used for acoustic feedback control in the hearing aids due to its excellent performance. The commonly used adaptive filtering algorithms employ a fixed step-size,which has to compromise between the initial convergence and the steady-state misalignment. Many variable stepsize adaptive algorithms have been proposed to handle this problem. In this paper, we propose a broadband Kalman filter to resolve this problem. The acoustic feedback path is modelled by a first-order Markov model,and the observation equation is constructed using more past data vector. A major issue in the hearing aids is the computational complexity. We thus present a simplified version to reduce the complexity, which bridges between the exact Kalman filter and the affine projection algorithm. The estimation of the process and measurement noise variance is discussed in detail. A two-feedbackpath model is adopted to improve the algorithm’s lack of re-convergence. Simulation results confirm the proposed algorithm clearly outperforms the other variable step-size adaptive filtering approaches.

关键词： Acoustic feedback cancellation Kalman filter Convergence rate Tracking capability

Unsteadiness control of laminar junction flows on pressure fluctuations

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Applied Mathematics and Mechanics(English Edition) 2019年第3期40卷 373-380页

作者： Jianhua LIU Shucheng ZHAI E.KUDASHEV Fangwen HONG Kai YAN China Ship Scientific research Center National key laboratory on Ship vibration & noise Space research Institute of Russian Academy of Sciences

Smoke-wire flow visualization is conducted carefully in a laminar junction to explore the physical behavior of laminar junction flows. The two-dimensional(2 D)velocity fields in the 30?plane of a laminar junction flow are acquired by a time-resolved particle image velocimetry(PIV) system at a frame rate of 1 kHz, based on which the unsteady fluctuating pressure fields can be calculated by the multi-path integration method proposed in the literature(GAND, F., DECK, S., BRUNET,V., and SAGAUT, P. Flow dynamics past a simplified wing body junction. Physics of Fluids, 22(11), 115111(2010)).A novel control strategy is utilized to attenuate the unsteadiness of the horseshoe vortices of the laminar junction flow, and the consequent effect on pressure fields is analyzed.

关键词： junction flow horseshoe vortex pressure fluctuation flow visualization

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An on-line calibration hydrophone with electrostatic actuator

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Science China(Information Sciences) 2016年第6期59卷 240-247页

作者： Jingbin WANG Zhaoli YAN Bin CHEN Xiaobin CHENG key laboratory of noise and vibration research Institute of AcousticsChinese Academy of Sciences School of Automation Beijing University of Posts and Telecommunications

On-line sensitivity calibration of hydrophones is of considerable significance for their practical application. An on-line method using an electrostatic actuator is proposed in this paper for a radially polarized cylindrical piezoelectric hydrophone. The theory of this calibration method is analyzed. A calibration structure with an electrostatic actuator is designed, and is integrated with the hydrophone sensing element. The sensitivity and frequency characteristics of the electrostatic actuator are measured experimentally. The sensitivity of the hydrophone is calibrated and compared with its free-field sensitivity. Uncertainty analysis shows that the expanded uncertainty of the proposed calibration method is about 1.1 d B at a confidence probability of 95%,which meets the uncertainty requirements for hydrophone sensitivity calibration.

关键词： underwater measurement hydrophone on-line sensitivity calibration electrostatic actuator uncertainty

Investigations on vortex structures for undulating fin propulsion using phase-locked digital particle image velocimetry

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Journal of Hydrodynamics 2021年第3期33卷 572-582页

作者： Ya-qiang Bai Jun Zhang Shu-cheng Zhai Guo-ping Zhang China Ship Scientific research Center Wuxi214082China National key laboratory on Ship vibration and noise Wuxi214082China

The Gymnarchus niloticus fish can swim in surging and heaving directions only with a long undulating ribbon fin while keeping its body along almost straight *** features substantially inspire the design of underwater vessels with high maneuverability and station keeping performance,which is characterized by peculiar vortex structures induced by undulating fin *** reveal the propulsion mechanism under the evolution of these complex vortex structures,the variation of velocity field with the undulating fin’s wave phase on cross section and mid-sagittal plane at wave amplitude of 85°is investigated by phase-locked digital particle image velocimetry(DPIV).Through experimental flow field images,two typical vortex structures are clearly identified,i.e.,streamwise vortex and crescent vortex,which is further explained by supplemental numerical simulations using large eddy *** characteristic and its evolution on cross sections and mid-sagittal planes is investigated,and its relationship with thrust,heave force is also *** is found that the two kinds of vortexes induce the main hydrodynamic forces in two directions synchronously,which brings the undulating fin propulsion an extra-ordinal *** research will be useful for understanding the potential mechanism of this novel propulsion and is of great application prospect in designing more maneuverable underwater vehicles.

关键词： Undulating fin propulsion vortex structure phase-locked digital particle image velocimetry(DPIV) hydrodynamic mechanism