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[IEEE 2019 18th International Conference on Optical Communications and Networks (ICOCN) - Huangshan, China (2019.8.5-2019.8.8)] 2019 18th International Conference on Optical Communications and Networks (ICOCN) - Theoretical and experimental study on optical fiber microseismic accelerometer based on cantilever beam structure
摘要： According to the characteristics of underground environment and microseismic signal in coal mine, a kind of optical fiber microseismic accelerometer based on cantilever beam structure is put forward in this paper, and its mechanical model is established, its sensitivity is analyzed, and tested by B&K shaking table test system. The experimental results show that the frequency response range of the sensor is 10Hz-100Hz, which meets the requirements of microseismic test.
关键词： FBG,accelerometer,microseismic,cantilever beam,frequency response
更新于2025-09-16 10:30:52
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[IEEE 2019 18th International Conference on Optical Communications and Networks (ICOCN) - Huangshan, China (2019.8.5-2019.8.8)] 2019 18th International Conference on Optical Communications and Networks (ICOCN) - Research on the resonance frequency reduction of the single fiber scanner
摘要： Single fiber scanner has been applied in many fields, such as minimally invasive surgery, nondestructive testing(NDT), borescopy technology. The resonance frequency of the single fiber cantilever is an important parameter for a scanner. Especially in the application of OCT (Optical Coherence Tomography), a relatively low resonance frequency is required. In this study, we proposed a new method to lower the resonance frequency of the single fiber scanner, other than simply lengthening the fiber. The simulation results agree well with the measured data.
关键词： single fiber scanner,fiber cantilever,resonance frequency
更新于2025-09-16 10:30:52
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[IEEE 2019 18th International Conference on Optical Communications and Networks (ICOCN) - Huangshan, China (2019.8.5-2019.8.8)] 2019 18th International Conference on Optical Communications and Networks (ICOCN) - Overhead Transmission Line Tensiometer on Insulator String Based on Fiber Bragg Grating
摘要： This paper proposes an overhead transmission line tensiometer on insulator string based on fiber Bragg grating and cantilever beam. According to simulation and experiment, the tensiometer is suitable for overhead transmission line breakage warning.
关键词： tensiometer,fiber Bragg grating,cantilever beam
更新于2025-09-16 10:30:52
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A novel methodology for spark gap monitoring in Micro-EDM using optical fiber Bragg grating
摘要： Micro-Electric Discharge Machining (Micro-EDM) are the most considerable micro-manufacturing process used to engineer miniaturized features on any high temperature resistive hard material. The machining parameters in Micro-EDM are very stochastic in nature. The spark gap measure acts as a vital parameter that correlates with other process parameters for enhancement of Material Removal Rate (MRR) in Micro-EDM. Real-time actual measurement of spark gap between the electrodes is highly challenging and is limited due to the small gap measure. The present work is on development of a novel sensing technique for spark gap measurement, based on a Fiber Bragg Grating (FBG) sensor. The sensing system is developed on a cantilever structure bonded with the FBG sensor, for determining accurate spark gap measure with displacement measurement of the tool electrode. The deflection on the cantilever during spark gap generation is translated into strain variations monitored by the FBG bonded over it. Experimental trials are conducted on Micro-EDM set-up with the cantilever beam based displacement sensing with a sensitivity of 10 μm/pm. Real-time spark gap data obtained by FBG are in the range of 1.1-18.6 μm and are validated against a precision measuring instrument. This sensing technology employed for Micro-EDM spark gap measurement establishes a novel technique in micromachining field and formulates a smart system.
关键词： Cantilever beam structure,Micromachining,Spark gap,Fiber optics,Micro-EDM,Bragg Gratings
更新于2025-09-12 10:27:22
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Influence of system parameters on buckling and frequency analysis of a spinning cantilever cylindrical 3D shell coupled with piezoelectric actuator
摘要： In this research, buckling and vibrational characteristics of a spinning cylindrical moderately thick shell covered with piezoelectric actuator carrying spring-mass systems are performed. This structure rotates about axial direction and the formulations include the Coriolis and centrifugal effects. In addition, various cases of thermal (uniform, linear, and nonlinear) distributions are studied. The modeled cylindrical moderately thick shell covered with piezoelectric actuator, its equations of motion, and boundary conditions are derived by the Hamilton’s principle and based on a moderately cylindrical thick shell theory. For the first time in the present study, attached mass-spring systems has been considered in the rotating cylindrical moderately thick shells covered with piezoelectric actuator. The accuracy of the presented model is verified with previous studies. The novelty of the current study is consideration of the applied voltage, rotation, various temperature distributions, and mass-spring systems implemented on proposed model using moderately cylindrical thick shell theory. Generalized differential quadrature method is examined to discretize the model and to approximate the governing equations. In this study, the simply supported conditions have been applied to edges (cid:2) ? (cid:3)=2, 3(cid:3)=2 and cantilever (clamped–free) boundary conditions has been studied in x ? 0, L, respectively. Finally, the effects of the applied voltage, angular velocity, temperature changes, and spring-mass systems on the critical voltage, critical angular speed, critical temperature, and natural frequency of the structure are investigated.
关键词： cantilever cylindrical moderately thick shell,piezoelectric layer,spring-mass systems,spinning,Various thermal loading
更新于2025-09-12 10:27:22
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Micro-Cantilever Displacement Detection Based in Optical Fiber Tip
摘要： This work demonstrates the potential of combining a microsphere with a tip for the functionality of the contact sensor. This sensor consists of a tip aligned with the fiber core and a microsphere, which appears during tip formation. This new structure was produced using the electric arc machine. The sensor operation consists of the variation of the tip curvature, which causes a variation of the optical paths and, consequently, a change in the output signal. The study of this micro-cantilever consisted of an exploration of the contact mode. In addition, the sensor was characterized by temperature, which shows very low sensitivity and vibration. This last characterization was performed with two configurations parallel and perpendicular to the oscillating surface. The perpendicular case showed higher sensitivity and has an operating band of 0 Hz to 20 kHz. In this configuration, for frequencies up to 2 Hz, the intensity varies linearly with the frequencies and with a sensitivity of 0.032 ± 0.001 (Hz?1). For the parallel case, the operating band was from 1.5 kHz to 7 kHz.
关键词： detection,physic,cantilever,microsphere,optical fiber structure,optic,sensor,vibration,tip
更新于2025-09-12 10:27:22
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[IEEE 2019 Conference on Lasers and Electro-Optics Europe & European Quantum Electronics Conference (CLEO/Europe-EQEC) - Munich, Germany (2019.6.23-2019.6.27)] 2019 Conference on Lasers and Electro-Optics Europe & European Quantum Electronics Conference (CLEO/Europe-EQEC) - Sensitivity Enhancement of a Cantilever-Enhanced Photo-Acoustic Spectroscopic Sensor by an Optical Build-Up Cavity
摘要： Laser photo-acoustic spectroscopy (LPAS) is a highly sensitive and selective method for trace gas analysis. One of the most advanced LPAS techniques is cantilever-enhanced photo-acoustic spectroscopy (CEPAS), which can reach down to low-ppt and sub-ppt level trace gas detection sensitivities with high power lasers [1,2]. The selection of wavelengths and tunability of high power narrow linewidth lasers is, however, limited. They are also rarely suitable for field deployable analysers, which would require a small and robust form factor. An alternative approach, potentially overcoming these weaknesses, is to build up the optical power of a standard distributed feedback diode laser (DFB) or a quantum cascade laser in an external optical cavity [3,4]. Here, we show the first demonstration of enhancing the sensitivity of a CEPAS sensor with an external optical build-up cavity, a technique which we call the cavity-enhanced CEPAS (CE-CEPAS). We achieve an unprecedented normalised noise equivalent absorption (NNEA) value of 1.75×10-12 W cm-1 Hz -1/2. In our work, the NNEA results in 75 ppt noise equivalent concentration for C2H2 with a 10 s integration time in the 1530 nm wavelength range. Compared to standard CEPAS, the detection limit is better by a factor of 100, which corresponds to the power build-up factor (BUF) of our cavity. With operation in the near-infrared region, we benefit from the highly reliable and inexpensive components of the telecommunications industry, while achieving a detection sensitivity that is comparable to the state-of-the-art results obtained in the mid-infrared region, where the molecular absorption lines are typically two orders of magnitude stronger.
关键词： CEPAS,cantilever-enhanced photo-acoustic spectroscopy,CE-CEPAS,optical build-up cavity,trace gas analysis,cavity-enhanced CEPAS
更新于2025-09-11 14:15:04
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Mechanical modeling and characterization of suspended cooled silicon bolometers for sub-millimeter and millimeter waves polarization detection
摘要： Silicon bolometers for space and astronomy applications, fabricated in standard CMOS-SOI technology are now successfully used as cryogenic detectors working at very low temperature, typically in the range of 0.05–0.1 K. They feature a remarkably high electromagnetic absorption, high temperature sensitivity and low noise. However, the mechanical behavior of suspended silicon bolometers results from the fabrication process parameters and a good understanding of these mechanisms is necessary to better control their deformation. In this work, silicon bolometer pixels with a pitch of 1200 μm and 500 μm for millimeter-wave (mm-wave) polarization detection have been fabricated and their mechanical behavior is investigated at room temperature and cryogenic temperature. First, a mechanical model was developed based on simulated and experimental deformations at room temperature of multi-layer cantilever test structures with different Young’s modulus and thickness (Ei, hi). The actual multi-layer suspended structures are modeled as an equivalent composite layer with an effective Young’s modulus (Eeff), an effective thickness (heff) and residual stresses (σ0, σ1). The residual stress values are positive, corresponding to a tensile stress in the fabricated multilayer stack. The impact of the a-Si passivation thickness on the total stress is discussed. The equivalent model is used in the simulation of the full pixel structure and results in excellent agreement with optical measurements of the deflection at room temperature. At cryogenic temperatures, mechanical deformations can hardly be measured, so the mechanical behavior of a 500-μm pixel was simulated at 0.1 K assuming that tensile residual stresses coming from defects are independent on temperature, and a good mechanical stability of the pixel was obtained. The optical performance simulation of this 500-μm pixel is discussed and showed that the mechanical deformations result in a degradation of the Noise Equivalent Power (NEP) from 1.59 × 10?18 to 1.05 × 10?17 W/Hz1/2 for an optical load of 6 × 10?15 W at 0.1 K.
关键词： Multilayer mechanical model,Cantilever,Doped silicon,FEM,Bolometer
更新于2025-09-11 14:15:04
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Improved Optical Waveguide Microcantilever for Integrated Nanomechanical Sensor
摘要： This paper reports on an improved optical waveguide microcantilever sensor with high sensitivity. To improve the sensitivity, a buffer was introduced into the connection of the input waveguide and optical waveguide cantilever by extending the input waveguide to reduce the coupling loss of the junction. The buffer-associated optical losses were examined for different cantilever thicknesses. The optimum length of the buffer was found to be 0.97 μm for a cantilever thickness of 300 nm. With this configuration, the optical loss was reduced to about 40%, and the maximum sensitivity was more than twice that of the conventional structure.
关键词： sensitivity,optical waveguide cantilever sensor,buffer
更新于2025-09-11 14:15:04
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Influences of relative humidity on the quality factors of MEMS cantilever resonators in gas rarefaction
摘要： In this paper, the effect of relative humidity of moist air is discussed on the quality factor (Q factor) of micro-electro-mechanical systems (MEMS) cantilever resonators in wide range of gas rarefaction (ambient pressure and accommodation coefficients, ACs). The modified molecular gas lubrication (MMGL) equation is used to model the squeeze film damping problem of MEMS cantilever resonators. Dynamic viscosity and Poiseuille flow rate are used to modify the MMGL equation to consider the coupled effects of relative humidity and gas rarefaction. Thermoelastic damping and anchor loss, which are dominant damping mechanisms of MEMS cantilever resonators, are also included to calculate total Q factor. Thus, the influences of relative humidity are discussed on the Q factors of MEMS cantilever resonators in wide range of gas rarefaction and dimension of cantilever. The results showed that the Q factor decreases as relative humidity increases in wide range of gas rarefaction (pressure, and ACs) and dimension of cantilever (length, width, and thickness). The influences of relative humidity on the Q factor become more significantly in larger length, larger width, smaller thickness of cantilever, and higher gas rarefaction (lower pressure and ACs). Whereas, the influences of relative humidity on the Q factor reduce or are neglected in smaller length, larger thickness of cantilever and lower gas rarefaction (higher pressure and ACs).
关键词： Anchor loss,Relative humidity,Quality factor,Gas rarefaction,Squeeze film damping,Thermoelastic damping,MEMS cantilever resonators
更新于2025-09-10 09:29:36