Статті в журналах: "Mechanical mode sensing"

1

Lee, Jin-Hyuk. "Biomimetic idealization of a mechanically coupled acoustic sound sensing mechanism." SIMULATION 94, no. 2 (June 15, 2017): 131–43. http://dx.doi.org/10.1177/0037549717712038.

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This paper presents the idealization of a mechanically coupled acoustic sensor mechanism for directivity with the use of polysilicon, which has ideal mechanical and electrical material properties in terms of micro-fabrication. A mathematical model related to mechanical sensitivity is developed as a function of the material properties and geometry of the sensor, which evaluates the characteristics of a two-degree-of-freedom-based lumped parameter model. A challenge in such a study is that the model needs to be simple but sufficiently sophisticated to capture the characteristics of the sensor mechanism. Eigen modes and frequencies of the mechanically coupled acoustic sensor mechanism are determined by an energy method using mode functions applicable to the complete system that are from admissible the mode functions chosen for the component elements of the system. The synthesis is accomplished by using equations of constraint that follow conditions imposed by force equilibrium and deflection compatibility at the junctions. Finally, the results are compared with those obtained by a full-scale finite element model developed in a commercial software package. The predicted first and second natural frequencies differed by less than 10% and 3%, respectively, in all test cases.

2

Xia, Ji, Qifeng Qiao, Guangcan Zhou, Fook Siong Chau, and Guangya Zhou. "Opto-Mechanical Photonic Crystal Cavities for Sensing Application." Applied Sciences 10, no. 20 (October 12, 2020): 7080. http://dx.doi.org/10.3390/app10207080.

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A new class of hybrid systems that couple optical and mechanical nanoscale devices is under development. According to their interaction concepts, two groups of opto-mechanical systems are summarized as mechanically tunable and radiation pressure-driven optical resonators. On account of their high-quality factors and small mode volumes as well as good on-chip integrability with waveguides/circuits, photonic crystal (PhC) cavities have attracted great attention in sensing applications. Benefitting from the opto-mechanical interaction, a PhC cavity integrated opto-mechanical system provides an attractive platform for ultrasensitive sensors to detect displacement, mass, force, and acceleration. In this review, we introduce basic physical concepts of opto-mechanical PhC system and describe typical experimental systems for sensing applications. Opto-mechanical interaction-based PhC cavities offer unprecedented opportunities to develop lab-on-a-chip devices and witness a promising prospect to further manipulate light propagation in the nanophotonics.

3

Novotný, Vít, Petr Sysel, Aleš Prokeš, Pavel Hanák, Karel Slavíček, and Jiří Přinosil. "Fiber Optic Based Distributed Mechanical Vibration Sensing." Sensors 21, no. 14 (July 13, 2021): 4779. http://dx.doi.org/10.3390/s21144779.

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The distributed long-range sensing system, using the standard telecommunication single-mode optical fiber for the distributed sensing of mechanical vibrations, is described. Various events generating vibrations, such as a walking or running person, moving car, train, and many other vibration sources, can be detected, localized, and classified. The sensor is based on phase-sensitive optical time-domain reflectometry (ϕ-OTDR). Related sensing system components were designed and constructed, and the system was tested both in the laboratory and in the real deployment, with an 88 km telecom optical link, and the results are presented in this paper. A two-fiber sensor unit, with a double-sensing range was also designed, and its scheme is described. The unit was constructed and the initial measurement results are presented.

4

Quanyi, Hu, Zhang Hong, Tian Shujun, and Qin Xuxin. "Performances analysis of a novel load-sensing hydraulic system with overriding differential pressure control." Proceedings of the Institution of Mechanical Engineers, Part C: Journal of Mechanical Engineering Science 231, no. 23 (September 3, 2016): 4331–43. http://dx.doi.org/10.1177/0954406216667760.

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The traditional load-sensing hydraulic system is an energy-saving fluid power transmission, which supply “on-demand” flow at a prescribed pressure margin greater than the highest load pressure of the system. In this paper, a novel load-sensing system that has a variable pressure margin through overriding differential pressure control via integrating an electro-proportional three-way type pressure reducing valve into the hydro-mechanical load-sensing valve is proposed. Also, a bond graph model taking into account the dynamic characteristics of load-sensing valve and load-sensing path is constructed, and three group experiments are performed to verify the validation of the model. Based on the bond graph model, a series of theoretical simulations are carried out to prove that the proposed Load-Sensing system enables a satisfactory balance between energy efficiency and rapid dynamic response over a wide range of operating conditions. In addition, due to overriding differential pressure control, mode selection and power limit regulation can also be achieved.

5

Kan, Wenqing, Ying Huang, Xiao Zeng, Xiaohui Guo, and Ping Liu. "A dual-mode proximity sensor with combination of inductive and capacitive sensing units." Sensor Review 38, no. 2 (March 19, 2018): 199–206. http://dx.doi.org/10.1108/sr-06-2017-0111.

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Purpose The purpose of this paper is to present a dual-mode proximity sensor composed of inductive and capacitive sensing modes, which can help the robot distinguish different objects and obtain distance information at the same time. A systematic study of sensor response to various objects and the function of cooperation sensing is needed. Furthermore, the application in the field of robotic area needs to be discussed. Design/methodology/approach Numerical modeling of each sensing modes and simulations based on finite element analysis method has been carried out to verify the designed dual-mode sensor. A number of objects composed of different materials are used to research the cooperation perception and proximity sensing functions. In addition, the proposed sensor is used on the palm of a mechanical hand as application experiment. Findings The characteristics of the sensor are summarized as follows: the sensing range of inductive mode is 0-5.6 mm for detecting a copper block and the perceive range of capacitive mode is 0-5.1 mm for detecting a plastic block. The collaborative perceive tests validated that the non-ferromagnetism metals can be distinguished by inductive mode. Correspondingly, ferromagnetism metals and dielectric objects are differentiated by capacitive mode. Application experiments results reveal that both plastic bottle and steel bottle could be detected and differentiated. The experimental results are in agreement with those of simulations. Originality value This paper provides a study of dual-mode proximity sensor in terms of design, experiments and application.

6

Yin, Rui, Rui Wang, Xiang Yang Zhou, Xiang Yang Peng, and Ke Wang. "Dynamic Modeling and Nonlinear Decoupling Control of Inertial Stabilized Platform for Aerial Remote Sensing System." Advanced Materials Research 898 (February 2014): 807–13. http://dx.doi.org/10.4028/www.scientific.net/amr.898.807.

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The mutual coupling between the motion of three frames exists when inertial stabilized platform (ISP) for aerial remote sensing system is working, due to the mechanical character of the stabilized platform. Based on Lagrange mechanics and starting from analytical mechanics, a kinetics model of inertial stabilized platform is developed for analyzing the complex coupling relation. On the basis of the model, a nonlinear decoupling control method using sliding mode control (SMC) is designed for rolling and pitching frames after coupling moment being taken for external disturbance. While, for azimuth frame, which can not directly adopt sliding mode control method, a novel method of introducing a judgment factor and combining SMC and PID is provided. Compared with PID method, the simulation results show that the overshoot of the system is reduced obviously and the decoupling effect is better. Results obtained will be a theoretical foundation for the further study of inertial stabilized platform, and guarantee high precision to stabilized platform system.

7

La Gala, Giada, John P Mathew, Pascal Neveu, and Ewold Verhagen. "Nanomechanical design strategy for single-mode optomechanical measurement." Journal of Physics D: Applied Physics 55, no. 22 (March 3, 2022): 225101. http://dx.doi.org/10.1088/1361-6463/ac569d.

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Abstract The motion of a mechanical resonator is intrinsically decomposed over a collection of normal modes of vibration. When the resonator is used as a sensor, its multimode nature often deteriorates or limits its performance and sensitivity. This challenge is frequently encountered in state-of-the-art optomechanical sensing platforms. We present a mechanical design strategy that ensures that optomechanical measurements can retrieve information on a single mechanical degree of freedom, and implement it in a sliced photonic crystal nanobeam resonator. A spectral design approach is used to make mechanical symmetries robust against practical disorder. The effectiveness of the method is evaluated by deriving a relevant figure of merit for continuous and pulsed measurement application scenarios. The method can be employed in any mechanical design that presents unwanted spurious mechanical modes. In the nanobeam platform, we experimentally show an increase of the signal to noise ratio of the mode of interest over the first spurious mode by four orders of magnitudes.

8

Zhao, Xuyang, Zhihe Guo, Yi Zhou, Junhong Guo, Zhiran Liu, Yuxiang Li, Man Luo, and Xiang Wu. "Optical Whispering-Gallery-Mode Microbubble Sensors." Micromachines 13, no. 4 (April 9, 2022): 592. http://dx.doi.org/10.3390/mi13040592.

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Whispering-gallery-mode (WGM) microbubble resonators are ideal optical sensors due to their high quality factor, small mode volume, high optical energy density, and geometry/design/structure (i.e., hollow microfluidic channels). When used in combination with microfluidic technologies, WGM microbubble resonators can be applied in chemical and biological sensing due to strong light–matter interactions. The detection of ultra-low concentrations over a large dynamic range is possible due to their high sensitivity, which has significance for environmental monitoring and applications in life-science. Furthermore, WGM microbubble resonators have also been widely used for physical sensing, such as to detect changes in temperature, stress, pressure, flow rate, magnetic field and ultrasound. In this article, we systematically review and summarize the sensing mechanisms, fabrication and packing methods, and various applications of optofluidic WGM microbubble resonators. The challenges of rapid production and practical applications of WGM microbubble resonators are also discussed.

9

Ng, T. W., and S. Thirunavukkarasu. "Optical Sensing Limits in Contact and Bending Mode Atomic Force Microscopy." Experimental Mechanics 47, no. 6 (March 9, 2007): 841–44. http://dx.doi.org/10.1007/s11340-007-9044-x.

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10

Zhang, Rui, Ran Guo, and Shiyue Wang. "Mixed mode fracture study of PMMA using digital gradient sensing method." Engineering Fracture Mechanics 119 (March 2014): 164–72. http://dx.doi.org/10.1016/j.engfracmech.2014.02.020.

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11

Tanaka, N., S. D. Snyder, and C. H. Hansen. "Distributed Parameter Modal Filtering Using Smart Sensors." Journal of Vibration and Acoustics 118, no. 4 (October 1, 1996): 630–40. http://dx.doi.org/10.1115/1.2888345.

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This paper considers the design of distributed parameter modal sensors called “smart sensors,” with a particular emphasis on filtering the combination of appropriately weighted vibration modes providing a specific performance index in control strategy. First, with a two-dimensional distributed parameter sensor using a PVDF film, the necessary and sufficient condition for sensing the transformed modes of a structure is derived. Then, by considering the practicability of the two-dimensional sensors, an alternative approach based upon one-dimensional smart sensors is presented. It is found that the latter approach holds the necessary condition for sensing the transformed mode. This problem is overcome by introducing multiple one-dimensional smart sensors. Moreover, the design procedure for the multiple one-dimensional smart sensors for measuring the transformed mode is established. Finally, an experiment is conducted, demonstrating the validity of the smart sensors.

12

Rahaman, Ashiqur, Haeil Jung, and Byungki Kim. "Coupled D33 Mode-Based High Performing Bio-Inspired Piezoelectric MEMS Directional Microphone." Applied Sciences 11, no. 3 (February 1, 2021): 1305. http://dx.doi.org/10.3390/app11031305.

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Microelectromechanical system (MEMS) directional microphones have been identified as having use in multi-projected virtual reality applications such as virtual meetings for projecting cameras. In these applications, the acoustic sensitivity plays a vital role as it biases the directional sensing, signal-to-noise ratio (SNR) and self-noise. The acoustic sensitivity is the multiplied outcome of the mechanical sensitivity and the electrical sensitivity. As the dimensions are limited in MEMS technology, the improvement of the acoustic sensitivity by reflecting the mechanical as well as electrical domains is a challenge. This paper reports on a new formation of the D33 mode, the coupled D33 mode, based on piezoelectric sensing to improve the acoustic functionalities. The unique advancement of the proposed D33 mode is that it allows multiple spans of the regular D33 mode to perform together, despite this increasing the diaphragm’s dimensions. At a reduced diaphragm size, the orientation of the coupled D33 mode realizes the maximum conversion of the mechanical deflection into electrical sensitivity. The significance of the proposed D33 mode in comparison to the regular D33 mode is simulated using COMSOL Multiphysics. Then, for a proof–of–concept, the experimental validation is carried out using a piezoelectric MEMS directional microphone inspired by the ears of the fly Ormia ochracea. In both ways, the results are found to be substantially improved in comparison with the regular approach of the D33 mode, showing the novelty of this work.

13

Wu, Xiaodong, Maruf Ahmed, Yasser Khan, Margaret E. Payne, Juan Zhu, Canhui Lu, James W. Evans, and Ana C. Arias. "A potentiometric mechanotransduction mechanism for novel electronic skins." Science Advances 6, no. 30 (July 2020): eaba1062. http://dx.doi.org/10.1126/sciadv.aba1062.

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Human skin perceives external mechanical stimuli by sensing the variation in the membrane potential of skin sensory cells. Many scientists have attempted to recreate skin functions and develop electronic skins (e-skins) based on active and passive sensing mechanisms. Inspired by the skin sensory behavior, we investigated materials and electronic devices that allow us to encode mechanical stimuli into potential differences measured between two electrodes, resulting in a potentiometric mechanotransduction mechanism. We present here a potentiometric mechanotransducer that is fabricated through an all-solution processing approach. This mechanotransducer shows ultralow-power consumption, highly tunable sensing behavior, and capability to detect both static and low-frequency dynamic mechanical stimuli. Furthermore, we developed two novel classes of sensing devices, including strain-insensitive sensors and single-electrode-mode e-skins, which are challenging to achieve using the existing methods. This mechanotransduction mechanism has broad impact on robotics, prosthetics, and health care by providing a much improved human-machine interface.

14

Xiao, Xing, Shang-Chun Fan, and Cheng Li. "The Effect of Edge Mode on Mass Sensing for Strained Graphene Resonators." Micromachines 12, no. 2 (February 12, 2021): 189. http://dx.doi.org/10.3390/mi12020189.

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Edge mode could disturb the ultra-subtle mass detection for graphene resonators. Herein, classical molecular dynamics simulations are performed to investigate the effect of edge mode on mass sensing for a doubly clamped strained graphene resonator. Compared with the fundamental mode, the localized vibration of edge mode shows a lower frequency with a constant frequency gap of 32.6 GHz, despite the mutable inner stress ranging from 10 to 50 GPa. Furthermore, the resonant frequency of edge mode is found to be insensitive to centrally located adsorbed mass, while the frequency of the fundamental mode decreases linearly with increasing adsorbates. Thus, a mass determination method using the difference of these two modes is proposed to reduce interferences for robust mass measurement. Moreover, molecular dynamics simulations demonstrate that a stronger prestress or a higher width–length ratio of about 0.8 could increase the low-quality factor induced by edge mode, thus improving the performance in mass sensing for graphene resonators.

15

Caliendo, Cinzia, Smail Sait, and Fouad Boubenider. "Love-Mode MEMS Devices for Sensing Applications in Liquids." Micromachines 7, no. 1 (January 21, 2016): 15. http://dx.doi.org/10.3390/mi7010015.

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16

Luo, Youlin, Xiao-Qing Luo, Jianji Yi, Jie Ou, Weihua Zhu, Zhiyong Chen, W. M. Liu, and Xinlin Wang. "Whispering-gallery mode resonance-assisted plasmonic sensing and switching in subwavelength nanostructures." Journal of Materials Science 56, no. 7 (December 1, 2020): 4716–26. http://dx.doi.org/10.1007/s10853-020-05581-8.

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17

Teng, Chuanxin, Fangda Yu, Shijie Deng, Houquan Liu, Libo Yuan, Jie Zheng, and Hongchang Deng. "Displacement Sensor Based on a Small U-Shaped Single-Mode Fiber." Sensors 19, no. 11 (June 3, 2019): 2531. http://dx.doi.org/10.3390/s19112531.

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A simple structure and easily fabricated displacement sensor was proposed and demonstrated based on a bending-induced fiber interferometer. In the design, the fiber interferometer was formed only by bending the single-mode fiber into a small U-shape without splicing, tapering, or heating pre-processing, which effectively reduces the complexity of the fabrication process, greatly enhances the mechanical strength of the sensor, and lowers the cost in the displacement sensing applications. The displacement sensing performances for the sensor with different bending radii of 3.3 mm, 4.4 mm, 5.0 mm, and 6.3 mm were investigated. Experimental results showed that the sensor had a good linear response, and for the bending radii of 3.3, 4.4, 5.0, and 6.3 mm, the proposed sensors showed high sensitivities of 134.3, 105.1, 120.9, and 144.1 pm/μm, respectively.

18

Liu, Li Qun, Yang Chen, Ya Shen Zhao, Chao Qun Xiang, Li Na Hao, and Zhou Li Zhao. "The Realization of Actuating and Sensing Integrated Gripper System." Advanced Materials Research 898 (February 2014): 696–700. http://dx.doi.org/10.4028/www.scientific.net/amr.898.696.

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Most of traditional manipulator does not meet experimental requirements of micromanipulation for its large structure and complicated driven mode. Comparatively speaking, using actuating and sensing performance of IPMC gripper can well be applied to specific micro operations and mechanical testing environment. This paper designs one kind of IPMC gripper of actuating and sensing performance based on micro operation and micro assembly, which is applied to grab the cells and fix under a microscope.

19

Xia, Ji, Fuyin Wang, Chunyan Cao, Zhengliang Hu, Heng Yang, and Shuidong Xiong. "A Nanoscale Photonic Crystal Cavity Optomechanical System for Ultrasensitive Motion Sensing." Crystals 11, no. 5 (April 21, 2021): 462. http://dx.doi.org/10.3390/cryst11050462.

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Optomechanical nanocavities open a new hybrid platform such that the interaction between an optical cavity and mechanical oscillator can be achieved on a nanophotonic scale. Owing to attractive advantages such as ultrasmall mass, high optical quality, small mode volume and flexible mechanics, a pair of coupled photonic crystal nanobeam (PCN) cavities are utilized in this paper to establish an optomechanical nanosystem, thus enabling strong optomechanical coupling effects. In coupled PCN cavities, one nanobeam with a mass meff~3 pg works as an in-plane movable mechanical oscillator at a fundamental frequency of πΩm/2π=4.148 MHz. The other nanobeam couples light to excite optical fundamental supermodes at 1542.858 and 1554.464 nm with a Qo larger than 4 × 104. Because of the optomechanical backaction arising from an optical force, abundant optomechanical phenomena in the unresolved sideband are observed in the movable nanobeam. Moreover, benefiting from the in-plane movement of the flexible nanobeam, we achieved a maximum displacement of the movable nanobeam as 1468 fm/Hz1/2. These characteristics indicate that this optomechanical nanocavity is capable of ultrasensitive motion measurements.

20

Li, Peng, Feng Li, Yongshun Liu, Fengfeng Shu, Junfeng Wu, and Yihui Wu. "Temperature insensitive mass sensing of mode selected phononic crystal cavity." Journal of Micromechanics and Microengineering 25, no. 12 (November 13, 2015): 125027. http://dx.doi.org/10.1088/0960-1317/25/12/125027.

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21

He, Ya, Kun Feng, Minghui Hu, and Jinmiao Cui. "An MCM-Enhanced Compressive Sensing for Weak Fault Feature Extraction of Rolling Element Bearings under Variable Speeds." Shock and Vibration 2020 (August 13, 2020): 1–21. http://dx.doi.org/10.1155/2020/1745184.

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The compressive sensing (CS) theory provides a new slight to the big-data problem led by the Shannon sampling theorem in rolling element bearings condition monitoring, where the measurement matrix of CS tends to be designed by the random matrix (RM) to preserve the integrity of signal roughly. However, when the signal to be analyzed is infected with strong noise, not only does the signal become insufficiently sparse, but the randomness of the measurement matrix will bring down the sensing efficiency, resulting in the loss of fault feature. Thus, a sensing-enhanced CS scheme based on a series of modes after VMD decomposition is proposed under this paper. The core of this scheme is as follows: (1) the principal mode of VMD with better sparsity replaces the raw signal for compressive sensing; (2) all these modes contain the time-frequency characteristics of the raw signal; (3) a new measurement matrix called mode-circulant matrix (MCM) is defined by circulating the mode matrix, and when the amount of samples is shrunk, the sensing efficiency can be enhanced greatly. Besides, considering the fault signal of rolling bearings under variable speed, there is a need to use order tracking to overcome the nonstationarity of the signal before applying CS theory. The analysis results of simulation and experiment prove that the VMD- and MCM-based CS can successfully extract the weak fault feature of rolling bearings with operating speed changing.

22

Yuan, Qian, Liu, Wang, and Yu. "Highly Sensitive Temperature and Humidity Sensor Based on Carbon Nanotube-Assisted Mismatched Single-Mode Fiber Structure." Micromachines 10, no. 8 (August 6, 2019): 521. http://dx.doi.org/10.3390/mi10080521.

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Here we report on a miniaturized optical interferometer in one fiber based on two mismatched nodes. The all-fiber structure shows stable performance of temperature and humidity sensing. For temperature sensing in large ranges, from 40 to 100 °C, the sensor has a sensitivity of 0.24 dB/°C, and the adjusted R-squared value of fitting result reaches 0.99461 which shows a reliable sensing result. With carbon nanotubes coating the surface of the fiber, the temperature sensitivity is enhanced from 0.24561 to 1.65282 dB/°C in a small region, and the performance of humidity sensing becomes more linear and applicable. The adjusted R-squared value of the linear fitting line for humidity sensing shows a dramatic increase from 0.71731 to 0.92278 after carbon nanotube coating, and the humidity sensitivity presents 0.02571 nm/%RH.

23

O’Donnell, Jacob, Vijaya Chalivendra, Asha Hall, and Yong Kim. "Damage sensing in multi-functional glass fiber composites under mode-I fracture loading." Journal of Composite Materials 54, no. 30 (June 30, 2020): 4821–29. http://dx.doi.org/10.1177/0021998320939637.

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A detailed experimental study is performed for piezo resistance damage sensing on conductive glass fiber/epoxy composites under mode-I fracture conditions. The conductive composites are fabricated by homogeneously dispersing carbon nanotubes (CNTs) within the epoxy matrix and electro-flocking short carbon fibers onto the laminates along with a vacuum infusion process. A parametric study is done on the in-situ damage sensing properties by varying the carbon fiber lengths (150 µm and 350 µm) and the carbon fiber areal densities (500, 1000, 1500, and 2000 fibers/mm2). The change in resistance is captured with a four-point probe measuring methodology by measuring the resistance through the thickness of the composite. The crack initiation toughness value of the composites containing carbon fibers showed improvement over control composites. Composites containing 350 µm length carbon fibers and 2000 fiber/mm2 not only showed the best crack initiation toughness but also provided sensitive network for detecting crack growth.

24

Morozov, N. F., D. A. Indeitsev, V. S. Igumnova, A. V. Lukin, I. A. Popov, and L. V. Shtukin. "Nonlinear dynamics of mode-localized MEMS accelerometer with two electrostatically coupled microbeam sensing elements." International Journal of Non-Linear Mechanics 138 (January 2022): 103852. http://dx.doi.org/10.1016/j.ijnonlinmec.2021.103852.

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25

Li, Lei, Yin-ping Zhang, Chi-cheng Ma, Can-chang Liu, and Bo Peng. "Anti-Symmetric Mode Vibration of Electrostatically Actuated Clamped–Clamped Microbeams for Mass Sensing." Micromachines 11, no. 1 (December 19, 2019): 12. http://dx.doi.org/10.3390/mi11010012.

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This paper details study of the anti-symmetric response to the symmetrical electrostatic excitation of a Micro-electro-mechanical-systems (MEMS) resonant mass sensor. Under higher order mode excitation, two nonlinear coupled flexural modes to describe MEMS mass sensors are obtained by using Hamilton’s principle and Galerkin method. Static analysis is introduced to investigate the effect of added mass on the natural frequency of the resonant sensor. Then, the perturbation method is applied to determine the response and stability of the system for small amplitude vibration. Through bifurcation analysis, the physical conditions of the anti-symmetric mode vibration are obtained. The corresponding stability analysis is carried out. Results show that the added mass can change the bifurcation behaviors of the anti-symmetric mode and affect the voltage and frequency of the bifurcation jump point. Typically, we propose a mass parameter identification method based on the dynamic jump motion of the anti-symmetric mode. Numerical studies are introduced to verify the validity of mass detection method. Finally, the influence of physical parameters on the sensitivity of mass sensor is analyzed. It is found that the DC voltage and mass adsorption position are critical to the sensitivity of the sensor. The results of this paper can be potentially useful in nonlinear mass sensors.

26

Svilicic, Boris, Graham S. Wood, Enrico Mastropaolo, and Rebecca Cheung. "Thermal- and Piezo-Tunable Flexural-Mode Resonator With Piezoelectric Actuation and Sensing." Journal of Microelectromechanical Systems 26, no. 3 (June 2017): 609–15. http://dx.doi.org/10.1109/jmems.2017.2680465.

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27

Yang, Zhaohua, Dan Li, and Yuzhe Sun. "Analysis of Kerr Noise in Angular-Rate Sensing Based on Mode Splitting in a Whispering-Gallery-Mode Microresonator." Micromachines 10, no. 2 (February 23, 2019): 150. http://dx.doi.org/10.3390/mi10020150.

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Whispering-gallery-mode (WGM) microresonators have shown their potential in high-precision gyroscopes because of their small volume and high-quality factors. However, Kerr noise can always be the limit of accuracy. Angular-rate sensing based on mode splitting treats backscattering as a measured signal, which can induce mode splitting, while it is considered as a main source of noise in conventional resonator optical gyroscopes. Meanwhile, mode splitting also provides superior noise suppression owing to its self-reference scheme. Kerr noise in this scheme has not been defined and solved yet. Here, the mechanism of the Kerr noise in the measurement is analyzed and the mathematical expressions are derived, indicating the relationship between the Kerr noise and the output of the system. The influence caused by Kerr noise on the output is simulated and discussed. Simulations show that the deviation of the splitting caused by Kerr noise is 1.913 × 10−5 Hz at an angular rate of 5 × 106 °/s and the corresponding deviation of the angular rate is 9.26 × 10−9 °/s. It has been proven that angular-rate sensing based on mode splitting offers good suppression of Kerr noise.

28

Kang, Seok-Won, Joe Fragala, Su-Ho Kim, and Debjyoti Banerjee. "Design and Electro-Thermo-Mechanical Behavior Analysis of Au/Si3N4 Bimorph Microcantilevers for Static Mode Sensing." Sensors 17, no. 11 (November 1, 2017): 2510. http://dx.doi.org/10.3390/s17112510.

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29

Xu, Yuanjie, and Joshua E.-Y. Lee. "Characterization and modeling of a contour mode mechanical resonator using piezoresistive sensing with quasi-differential inputs." Journal of Micromechanics and Microengineering 22, no. 12 (November 6, 2012): 125018. http://dx.doi.org/10.1088/0960-1317/22/12/125018.

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30

Wen, Jiao, Xiao Ming Liu, Zhong Gan Zhu, and Ming Cai. "Improved Structural Design and Digital Control System for Micro-Machined Tuning Fork Gyroscope." Advanced Materials Research 383-390 (November 2011): 5997–6002. http://dx.doi.org/10.4028/www.scientific.net/amr.383-390.5997.

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This paper proposes an improved design of micro-machined tuning fork gyroscope (M-TFG) to better decouple the cross talk between the driving and sensing directions and to increase resolution. By employing dual-folds spring suspension, the drive mode and the sense mode are mechanically decoupled. Through careful layout design of the location of the dual-folds spring suspension and the drive combs, the mechanical coupling effect is further decreased by isolating the unwanted excitation from detection. The peripheral circuit is also the important part to realize the function of the gyro system. Since the analog circuit has some inherent shortcomings, which has limited the accuracy of the gyro. In this paper, a digital control system for micro-comb is introduced.

31

Hong, Wan, Jian Zhang, Gang Wu, and Zhishen Wu. "Comprehensive comparison of macro-strain mode and displacement mode based on different sensing technologies." Mechanical Systems and Signal Processing 50-51 (January 2015): 563–79. http://dx.doi.org/10.1016/j.ymssp.2014.05.011.

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32

Liu, Shuai, Fang Yuan, Min Sang, Jianyu Zhou, Junshuo Zhang, Sheng Wang, Jinsong Li, Shouhu Xuan, and Xinglong Gong. "Functional sponge-based triboelectric nanogenerators with energy harvesting, oil–water separating and multi-mode sensing performance." Journal of Materials Chemistry A 9, no. 11 (2021): 6913–23. http://dx.doi.org/10.1039/d0ta12359e.

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A multi-functional triboelectric nanogenerator (TENG) is developed, which enables to sense mechanical/magnetic stimuli in the self-powered manner, and presents favorable magneto-driven and target recognization performance for spilled oil treatment.

33

Weihnacht, Manfred. "Multi-parameter sensing using thickness shear mode (TSM) resonators – a feasibility analysis." Journal of Sensors and Sensor Systems 8, no. 1 (April 3, 2019): 133–47. http://dx.doi.org/10.5194/jsss-8-133-2019.

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Abstract. Multi-parameter sensing is examined for thickness shear mode (TSM) resonators that are in mechanical contact with thin films and half-spaces on both sides. An expression for the frequency-dependent electrical admittance of such a system is derived which delivers insight into the set of material and geometry parameters accessible by measurement. Further analysis addresses to the problem of accuracy of extracted parameters at a given uncertainty of experiment. Crucial quantities are the sensitivities of measurement quantities with respect to the searched parameters determined as the first derivatives by using tentative material and geometry parameters. These sensitivities form a Jacobian matrix which is used for the exemplary study of a system consisting of a TSM resonator of AT-cut quartz coated by a copper layer and a glycerol half-space on top. Resonant and anti-resonant frequencies and bandwidths up to the 16th overtone are evaluated in order to extract the full set of six material–geometry parameters of this system as accurately as possible. One further outcome is that the number of employed measurement values can be extremely reduced when making use of the knowledge of the Jacobian matrix calculated before.

34

Asadi, Keivan, Jun Yu, and Hanna Cho. "Nonlinear couplings and energy transfers in micro- and nano-mechanical resonators: intermodal coupling, internal resonance and synchronization." Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences 376, no. 2127 (July 23, 2018): 20170141. http://dx.doi.org/10.1098/rsta.2017.0141.

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Extensive development of micro/nano-electromechanical systems (MEMS/NEMS) has resulted in technologies that exhibit excellent performance over a wide range of applications in both applied (e.g. sensing, imaging, timing and signal processing) and fundamental sciences (e.g. quantum-level problems). Many of these outstanding applications benefit from resonance phenomena by employing micro/nanoscale mechanical resonators often fabricated into a beam-, membrane- or plate-type structure. During the early development stage, one of the vibrational modes (typically the fundamental mode) of a resonator is considered in the design and application. In the past decade, however, there has been a growing interest in using more than one vibrational mode for the enhanced functionality of MEMS/NEMS. In this paper, we review recent research efforts to investigate the nonlinear coupling and energy transfers between multiple modes in micro/nano-mechanical resonators, focusing especially on intermodal coupling, internal resonance and synchronization. This article is part of the theme issue ‘Nonlinear energy transfer in dynamical and acoustical systems’.

35

Liu, Zhen, and Dihu Chen. "Upconversion photoluminescence and dual-mode temperature sensing properties of PIN-PMN-PT:Er3+ ceramic." Journal of Alloys and Compounds 815 (January 2020): 152092. http://dx.doi.org/10.1016/j.jallcom.2019.152092.

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36

Ramaswamy, S., H. V. Tippur, and L. Xu. "Mixed-mode crack-tip deformations studied using a modified flexural specimen and coherent gradient sensing." Experimental Mechanics 33, no. 3 (September 1993): 218–27. http://dx.doi.org/10.1007/bf02322577.

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37

Abbasi, Saad, Kevan Bell, and Parsin Haji Reza. "Rapid High-Resolution Mosaic Acquisition for Photoacoustic Remote Sensing." Sensors 20, no. 4 (February 14, 2020): 1027. http://dx.doi.org/10.3390/s20041027.

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Mechanical stages are routinely used to scan large expanses of biological specimens in photoacoustic imaging. This is primarily due to the limited field of view (FOV) provided by optical scanning. However, stage scanning becomes impractical at higher scanning speeds, or potentially unfeasible with heavier samples. Also, the slow scan-rate of the stages makes high resolution scanning a time-consuming process. Some clinical applications such as microsurgery require submicron resolution in a reflection-mode configuration necessitating a method that can acquire large field of views with a small raster scanning step size. In this study, we describe a method that combines mechanical stages with optical scanning for the rapid acquisition of high-resolution large FOVs. Optical scanning is used to acquire small frames in a two-dimensional grid formed by the mechanical stages. These frames are captured with specific overlap for effective image registration. Using a step size of 200 nm, we demonstrate mosaics of carbon fiber networks with FOVs of 0.8 × 0.8 mm2 captured in under 70 s with 1.2 µm image resolution. Larger mosaics yielding an imaging area of 3 × 3 mm2 are also shown. The method is validated by imaging a 1 × 1 mm2 section of unstained histopathological human tissue.

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Pathak, Medha M., Truc Tran, Liang Hong, Béla Joós, Catherine E. Morris, and Francesco Tombola. "The Hv1 proton channel responds to mechanical stimuli." Journal of General Physiology 148, no. 5 (October 17, 2016): 405–18. http://dx.doi.org/10.1085/jgp.201611672.

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The voltage-gated proton channel, Hv1, is expressed in tissues throughout the body and plays important roles in pH homeostasis and regulation of NADPH oxidase. Hv1 operates in membrane compartments that experience strong mechanical forces under physiological or pathological conditions. In microglia, for example, Hv1 activity is potentiated by cell swelling and causes an increase in brain damage after stroke. The channel complex consists of two proton-permeable voltage-sensing domains (VSDs) linked by a cytoplasmic coiled-coil domain. Here, we report that these VSDs directly respond to mechanical stimuli. We find that membrane stretch facilitates Hv1 channel opening by increasing the rate of activation and shifting the steady-state activation curve to less depolarized potentials. In the presence of a transmembrane pH gradient, membrane stretch alone opens the channel without the need for strong depolarizations. The effect of membrane stretch persists for several minutes after the mechanical stimulus is turned off, suggesting that the channel switches to a “facilitated” mode in which opening occurs more readily and then slowly reverts to the normal mode observed in the absence of membrane stretch. Conductance simulations with a six-state model recapitulate all the features of the channel’s response to mechanical stimulation. Hv1 mechanosensitivity thus provides a mechanistic link between channel activation in microglia and brain damage after stroke.

39

Liu, Yuhao, James J. S. Norton, Raza Qazi, Zhanan Zou, Kaitlyn R. Ammann, Hank Liu, Lingqing Yan, et al. "Epidermal mechano-acoustic sensing electronics for cardiovascular diagnostics and human-machine interfaces." Science Advances 2, no. 11 (November 2016): e1601185. http://dx.doi.org/10.1126/sciadv.1601185.

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Physiological mechano-acoustic signals, often with frequencies and intensities that are beyond those associated with the audible range, provide information of great clinical utility. Stethoscopes and digital accelerometers in conventional packages can capture some relevant data, but neither is suitable for use in a continuous, wearable mode, and both have shortcomings associated with mechanical transduction of signals through the skin. We report a soft, conformal class of device configured specifically for mechano-acoustic recording from the skin, capable of being used on nearly any part of the body, in forms that maximize detectable signals and allow for multimodal operation, such as electrophysiological recording. Experimental and computational studies highlight the key roles of low effective modulus and low areal mass density for effective operation in this type of measurement mode on the skin. Demonstrations involving seismocardiography and heart murmur detection in a series of cardiac patients illustrate utility in advanced clinical diagnostics. Monitoring of pump thrombosis in ventricular assist devices provides an example in characterization of mechanical implants. Speech recognition and human-machine interfaces represent additional demonstrated applications. These and other possibilities suggest broad-ranging uses for soft, skin-integrated digital technologies that can capture human body acoustics.

40

Chen, De-Shiou, Vadim I. Utkin, Shahram Zarei, and John M. Miller. "Real-Time Implementation of Sliding Mode Observer for Synchronous Rectification of the Automotive Electrical Power Supply System." Journal of Dynamic Systems, Measurement, and Control 122, no. 4 (May 25, 2000): 594–98. http://dx.doi.org/10.1115/1.1318243.

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This paper presents the methods for estimating automotive alternator’s back electromotive forces without a direct mechanical sensor of the rotor position. The design approach combines the merits of the sliding mode observer technique with the basics of a conventional observer. It is shown that the back electromotive forces may be observed based on system’s phase current model by sensing only electrical variables of the synchronous rectifier. Experimental results are presented for validation of the proposed observation algorithms. [S0022-0434(00)01404-0]

41

Bu, Huanxian, Xun Huang, and Xin Zhang. "A compressive-sensing-based method for radial mode analysis of aeroengine fan noise." Journal of Sound and Vibration 464 (January 2020): 114930. http://dx.doi.org/10.1016/j.jsv.2019.114930.

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42

Zhang, Hemin, Boyang Li, Weizheng Yuan, Michael Kraft, and Honglong Chang. "An Acceleration Sensing Method Based on the Mode Localization of Weakly Coupled Resonators." Journal of Microelectromechanical Systems 25, no. 2 (April 2016): 286–96. http://dx.doi.org/10.1109/jmems.2015.2514092.

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43

Lee, Yong-Woo, Joon-Young Soh, Il-Ryeol Yoo, Jiung Cho, Cheol-Woo Ahn, Jong-Jin Choi, Byung-Dong Hahn, and Kyung-Hoon Cho. "High Magnetic Field Sensitivity in Ferromagnetic–Ferroelectric Composite with High Mechanical Quality Factor." Sensors 20, no. 22 (November 19, 2020): 6635. http://dx.doi.org/10.3390/s20226635.

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In this study, composite devices were fabricated using ferromagnetic FeSiB-based alloys (Metglas) and ferroelectric ceramics, and their magnetic field sensitivity was evaluated. Sintered 0.95Pb(Zr0.52Ti0.48)O3-0.05Pb(Mn1/3Sb2/3)O3 (PZT-PMS) ceramic exhibited a very dense microstructure with a large piezoelectric voltage coefficient (g31 = −16.8 × 10−3 VmN−1) and mechanical quality factor (Qm > 1600). Owing to these excellent electromechanical properties of the PZT-PMS, the laminate composite with a Metglas/PZT-PMS/Metglas sandwich structure exhibited large magnetoelectric voltage coefficients (αME) in both off-resonance and resonance modes. When the length-to-width aspect ratio (l/w) of the composite was controlled, αME slightly varied in the off-resonance mode, resulting in similar sensitivity values ranging from 129.9 to 146.81 VT−1. Whereas in the resonance mode, the composite with small l/w exhibited a large reduction of αME and sensitivity values. When controlling the thickness of the PZT-PMS (t), the αME of the composite showed the largest value when t was the smallest in the off-resonance mode, while αME was the largest when t is the largest in the resonance mode. The control of t slightly affected the sensitivity in the off-resonance mode, however, higher sensitivity was obtained as t increased in the resonance mode. The results demonstrate that the sensitivity, varying with the dimensional control of the composite, is related to the mechanical loss of the sensor. The composite sensor with the PZT-PMS layer exhibited excellent magnetic field sensitivity of 1.49 × 105 VT−1 with a sub-nT sensing limit, indicating its potential for application in high-performance magnetoelectric sensor devices.

44

Teng, Chu-Hsiang, Troy A. Lionberger, Jin Zhang, Edgar Meyhöfer, and Pei-Cheng Ku. "Fabrication of nanoscale zero-mode waveguides using microlithography for single molecule sensing." Nanotechnology 23, no. 45 (October 19, 2012): 455301. http://dx.doi.org/10.1088/0957-4484/23/45/455301.

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45

Zhou, Xiangyang, Yuan Jia, and Yong Li. "An integral sliding mode controller based disturbances rejection compound scheme for inertially stabilized platform in aerial remote sensing." Proceedings of the Institution of Mechanical Engineers, Part G: Journal of Aerospace Engineering 232, no. 5 (April 19, 2017): 932–43. http://dx.doi.org/10.1177/0954410017703142.

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An integral sliding mode controller based disturbance rejection compound scheme is proposed to attenuate the influences of nonlinear disturbances and parameter uncertainties on stability accuracy of the three-axis inertially stabilized platform for the aerial remote sensing applications. The compound scheme is composed of an integral sliding mode controller and a disturbance measurement unit. The integral sliding mode controller is used to ensure robust stability against exterior nonlinear disturbances and parameter uncertainties, in which the saturation function is employed to reduce the chattering. The disturbance measurement unit is served as the disturbance measurement components of the rate loop and current loop of three closed-loop structure in the inertially stabilized platform control system, by which the interior high-frequency disturbances are compensated in real time. To verify the method, simulations and experiments are conducted. In simulations, the LuGre friction model is introduced to analyze the effects of disturbances. Further, a series of experiments are carried out. The results show that the compound scheme has excellent ability in both of disturbances rejection and robust stabilization, by which the stability accuracy of the inertially stabilized platform is improved significantly.

46

Bian, Zhongjian, Xiaofeng Hong, Yanan Guo, Lirida Naviner, Wei Ge, and Hao Cai. "Investigation of PVT-Aware STT-MRAM Sensing Circuits for Low-VDD Scenario." Micromachines 12, no. 5 (May 12, 2021): 551. http://dx.doi.org/10.3390/mi12050551.

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Spintronic based embedded magnetic random access memory (eMRAM) is becoming a foundry validated solution for the next-generation nonvolatile memory applications. The hybrid complementary metal-oxide-semiconductor (CMOS)/magnetic tunnel junction (MTJ) integration has been selected as a proper candidate for energy harvesting, area-constraint and energy-efficiency Internet of Things (IoT) systems-on-chips. Multi-VDD (low supply voltage) techniques were adopted to minimize energy dissipation in MRAM, at the cost of reduced writing/sensing speed and margin. Meanwhile, yield can be severely affected due to variations in process parameters. In this work, we conduct a thorough analysis of MRAM sensing margin and yield. We propose a current-mode sensing amplifier (CSA) named 1D high-sensing 1D margin, high 1D speed and 1D stability (HMSS-SA) with reconfigured reference path and pre-charge transistor. Process-voltage-temperature (PVT) aware analysis is performed based on an MTJ compact model and an industrial 28 nm CMOS technology, explicitly considering low-voltage (0.7 V), low tunneling magnetoresistance (TMR) (50%) and high temperature (85 ∘C) scenario as the worst sensing case. A case study takes a brief look at sensing circuits, which is applied to in-memory bit-wise computing. Simulation results indicate that the proposed high-sensing margin, high speed and stability sensing-sensing amplifier (HMSS-SA) achieves remarkable performance up to 2.5 GHz sensing frequency. At 0.65 V supply voltage, it can achieve 1 GHz operation frequency with only 0.3% failure rate.

47

Ghasemifard, Hadi, Hamid Behnam, and Jahan Tavakkoli. "Toward high-intensity focused ultrasound lesion quantification using compressive sensing theory." Proceedings of the Institution of Mechanical Engineers, Part H: Journal of Engineering in Medicine 231, no. 12 (October 5, 2017): 1152–64. http://dx.doi.org/10.1177/0954411917735557.

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Compressive sensing theory has in recent years been increasingly used in various pattern recognition applications. Compressive sensing theory makes it possible, under certain assumptions, to recover a signal or an image sampled below the Nyquist sampling limit. In this work, a new application of compressive sensing based on the threshold algorithm, in the area of controlling and monitoring of high-intensity focused ultrasound therapy, was investigated. In this work, a new method of high-intensity focused ultrasound lesion detection is presented based on a modified compressive sensing method in combination with the threshold algorithm and the wavelet transforms. In this study, analysis of the suggested method is performed using two sets of data: simulated and experimental ultrasound radio frequency data. The results of processing the data show that the proposed algorithm results in enhancement of the high-intensity focused ultrasound lesion contrast in comparison with the ultrasound B-mode and standard compressive sensing imaging methods. The results of the study show that the modified compressive sensing method could effectively detect thermal lesions in vitro. Comparing the estimated size of the thermal lesion (8.3 mm × 8.4 mm) using the proposed algorithm with the actual size of that from physical examination (10.1 mm × 9 mm) shows that we could detect high-intensity focused ultrasound thermal lesions with the difference of 0.8 mm × 0.5 mm.

48

Dong, Chunlin. "STUDY ON FRONT SIDE ARC LIGHT SENSING IN KEYHOLE MODE PLASMA ARC WELDING." Chinese Journal of Mechanical Engineering 37, no. 03 (2001): 30. http://dx.doi.org/10.3901/jme.2001.03.030.

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49

Bérces, G., J. Lendvai, A. Juhász, and N. Q. Chinh. "Dynamic characterization of Portevin–Le Chatelier instabilities occurring in depth-sensing microhardness tests." Journal of Materials Research 18, no. 12 (December 2003): 2874–81. http://dx.doi.org/10.1557/jmr.2003.0401.

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Characteristic properties of plastic instabilities were studied using depth-sensing microhardness experiments on an Al–3.3 wt.% Mg alloy and computer simulations based on a macroscopic dynamic model of the experimental setup. A stepwise increase was observed in the indentation depth versus load (d-F) curves measured in constant loading rate mode, indicating hardness oscillations around a nearly constant value of the conventional dynamic microhardness. These oscillations were correlated with plastic instabilities starting from the contact surface between the sample and the indenter head. Taking into account the experimentally determined connection between the hardness oscillations and the indentation velocity, a dynamic model was proposed for the characterization of instability steps.

50

Wang, H., and R. Kovacevic. "Feasibility study of acoustic sensing for the welding pool mode in variable-polarity plasma arc welding." Proceedings of the Institution of Mechanical Engineers, Part B: Journal of Engineering Manufacture 216, no. 10 (October 1, 2002): 1355–66. http://dx.doi.org/10.1243/095440502320405449.

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The relationships between the acoustic signal and the modes of the welding pool, such as no-keyhole (melt-in), keyhole and cutting, in variable-polarity plasma arc welding are investigated. The Welch power spectral density (PSD) estimate and short-time Fourier transformation are implemented to analyse and identify the different modes of the welding pool. The results show that the no-keyhole mode (melt-in welding process) can be clearly distinguished from the keyhole and the cutting modes. The keyhole size is inversely proportional to the Welch PSD estimate of the acoustic signal.

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