Research on the Disc Sensitive Structure of a Micro Optoelectromechanical System (MOEMS) Resonator Gyroscope

A micro optoelectromechanical system (MOEMS) resonator gyroscope based on a waveguide micro-ring resonator was proposed. This sensor was operated by measuring the shift of the transmission spectrum. Modal analysis was carried out for the disc sensitive structure of the MOEMS resonator gyroscope (MOEMS-RG). We deduced the equations between the equivalent stiffness and voltage of each tuning electrode and the modal parameters. A comprehensive investigation of the influences of the structure parameters on the sensitivity noise of the MOEMS-RG is presented in this paper. The mechanical sensitivity and transducer sensitivities of the MOEMS-RG, with varying structural parameters, are calculated based on the finite-element method. Frequency response test and the fiber optic spectrometer displacement test were implemented to verify the reliability of the model. Research results indicate that the resonant frequencies of the operating modes are tested to be 5768.407 Hz and 5771.116 Hz and the resonant wavelength change ΔX was 0.08 nm for 45° rotation angle. The resonant wavelength, which has a good linear response in working range, changes from −0.071 nm to 0.080 μm. The MOEMS-RG, with an optimized disc sensitive structure, can detect the deformation of the sensitive membrane effectively, and has a high sensitivity. This resonator shows very large meff, low f 0 , and very high Q. Therefore, this resonator can provide a small A R W B ( 0.09 ° / h ), which makes it a promising candidate for a low-cost, batch-fabricated, small size inertial-grade MOEMS gyroscope. The multi-objective optimization method could be expanded to include other objectives, constraints, or variables relevant to all kinds of gyroscopes or other microelectromechanical systems devices.

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Optimization of MEMS Design for a Synchronous Magnetic Sensor

Volume 11: Micro and Nano Systems, Parts A and B ◽

10.1115/imece2007-43572 ◽

2007 ◽

Author(s):

S. Chandrasekaran ◽

E. Berkcan

Keyword(s):

Thin Film ◽

Pathogen Detection ◽

Microelectromechanical Systems ◽

Gas Sensing ◽

Low Cost ◽

High Sensitivity ◽

Vibration Monitoring ◽

Flow Sensing ◽

Biological Warfare Agents ◽

Warfare Agents

Microelectromechanical systems offer variety of advantages such as small size, higher sensitivity, low cost because of mass fabrication capabilities and ease of implementation. Thin film cantilever based devices have been successfully used for variety of applications not limited to chemical vapors for chemical agents, biological warfare agents, contaminants in water, explosives, acoustics, vibration monitoring, flow sensing, viscosity and density measurements, antibody, pathogen detection, acceleration, shock sensing and magnetic field sensing. Thin film cantilevers can easily realized on silicon and other surfaces. Microcantilevers supported on one edge of the substrate can be designed to demonstrate very high sensitivity to very less force of the order of piconewtons. These structures could be extended for application in gas sensing if chemically sensitive layer is added on to the cantilever. The dimensions of the cantilever determine the sensitivity. Cantilevers as thin as few tenths of nanometer in thickness has been successfully demonstrated. Challenge associated with these devices when used as a sensor is their response to shock and acceleration.

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Design of a Surface Plasmon Resonance Temperature Sensor with Multi-Wavebands Based on Conjoined-Tubular Anti-Resonance Fiber

Photonics ◽

10.3390/photonics8060231 ◽

2021 ◽

Vol 8 (6) ◽

pp. 231

Author(s):

Qiming Wang ◽

Xuenan Zhang ◽

Xin Yan ◽

Fang Wang ◽

Tonglei Cheng

Keyword(s):

Surface Plasmon Resonance ◽

Surface Plasmon ◽

Plasmon Resonance ◽

Temperature Sensor ◽

Structural Parameters ◽

High Sensitivity ◽

Biological Research ◽

The Finite Element Method ◽

Practical Applications ◽

Spr Effect

In this work, a surface plasmon resonance (SPR) temperature sensor based on a con-joined-tubular anti-resonance optical fiber (CTF) was theoretically designed and analyzed using the finite element method. The CTF cladding was composed of eight pairs of conjoined tubes, and one or two holes of the tubes were selectively coated with gold to generate the SPR effect. Alcohol was injected into the core of the CTF to work as the sensing medium using vapor deposition. The proposed sensing structure exhibited excellent birefringence and produced more than six resonant peaks in different wavebands of the X and Y polarization. The positions of those resonant peaks were sensitive to temperature change, and the simulated sensitivity was about 3.2–3.6 nm/°C. The multiple working wavebands of the proposed sensing structure could be used for self-verification. Moreover, the influence of structural parameters on sensing performance was analyzed in detail. Possessing features of high sensitivity, good birefringence, multiple measuring wavebands, and self-verification, the proposed CTF-based SPR sensor has great potential in practical applications such as biological research and chemical sensing.

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An Hourglass-Shaped Wireless and Passive Magnetoelastic Sensor with an Improved Frequency Sensitivity for Remote Strain Measurements

Sensors ◽

10.3390/s20020359 ◽

2020 ◽

Vol 20 (2) ◽

pp. 359

Author(s):

Limin Ren ◽

Moyue Cong ◽

Yisong Tan

Keyword(s):

Resonant Frequency ◽

Simple Structure ◽

Low Cost ◽

Signal Transmission ◽

High Sensitivity ◽

Detection Sensitivity ◽

The Finite Element Method ◽

Resonant Sensor ◽

Parametric Studies ◽

Sensitivity Problem

The conventional magnetoelastic resonant sensor suffers from a low detecting sensitivity problem. In this study, an hourglass-shaped magnetoelastic resonant sensor was proposed, analyzed, fabricated, and tested. The hourglass-shaped magnetoelastic resonant sensor was composed of an hourglass and a narrow ribbon in the middle. The hourglass and the narrow ribbon increased the detection sensitivity by reducing the connecting stress. The resonant frequency of the sensor was investigated by the finite element method. The proposed sensor was fabricated and experiments were carried out. The tested resonance frequency agreed well with the simulated one. The maximum trust sensitivity of the proposed sensor was 37,100 Hz/strain. The power supply and signal transmission of the proposed sensor were fulfilled via magnetic field in a wireless and passive way due to the magnetostrictive effect. Parametric studies were carried out to investigate the influence of the hourglass shape on the resonant frequency and the output voltage. The hourglass-shaped magnetoelastic resonant sensor shows advantages of high sensitivity, a simple structure, easy fabrication, passiveness, remoteness, and low cost.

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Compliance Model and Structure Optimization Method Based on Genetic Algorithm for Flexure Hinge Based on X-Lattice Structure

Complexity ◽

10.1155/2021/8819422 ◽

2021 ◽

Vol 2021 ◽

pp. 1-14

Author(s):

Yin Zhang ◽

Jianwei Wu ◽

Jiubin Tan

Keyword(s):

Genetic Algorithm ◽

Lattice Structure ◽

Structural Parameters ◽

Structure Optimization ◽

Optimization Method ◽

Flexure Hinge ◽

The Finite Element Method ◽

Flexure Hinges ◽

Truss Model ◽

Compliance Model

In order to obtain a new structure of beam flexure hinge with good performance, the flexure hinge based on the X-lattice structure is researched in this paper. The truss model in the finite element method is used to model the 6-DOF compliance of the flexure hinge based on the X-lattice structure. The influence of structural parameters on the compliance and compliance ratio of flexure hinges is analyzed based on this model, and the performance is compared with the traditional beam flexure hinge of the same size. In order to design a flexure hinge based on the X-lattice structure with good comprehensive performance, this paper proposes an intelligent structure optimization method based on a genetic algorithm. The feasibility of the optimization algorithm is verified by an example.

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Kinematic Singularity and Bifurcation Analysis of Sidestay Landing Gear Locking Mechanisms

International Journal of Aerospace Engineering ◽

10.1155/2021/6685635 ◽

2021 ◽

Vol 2021 ◽

pp. 1-15

Author(s):

Kui Xu ◽

Yin Yin ◽

Yixin Yang ◽

Hong Nie ◽

Xiaohui Wei

Keyword(s):

Singular Point ◽

Structural Parameters ◽

Continuation Method ◽

High Sensitivity ◽

Optimization Method ◽

Landing Gear ◽

Singular Points ◽

Numerical Continuation ◽

Kinematic Optimization ◽

Kinematic Mechanism

A dual-sidestay landing gear is prone to locking failure in the deployed state due to the restriction of movement between two sidestays. However, the principle of its locking movement still remains unclear. The present study is aimed at investigating the synchronous locking performance of the dual-sidestay landing gear based on the singularity and bifurcation theory. From the perspective of the kinematic mechanism, the reason for high sensitivity to structural dimensions in the locking process is explained, and the locked position is investigated by employing the numerical continuation method in the case of a single-sidestay landing gear. Afterwards, the reason for the locking failure of the dual-sidestay landing gear is analyzed, and a kinematic optimization method for the synchronous locking is proposed. The results reveal that the lock links must reach the lower overcenter singular point to fully lock the landing gear, and the singular point is sensitively affected by structural parameters. Owing to the different positions of singular points, the movements of fore and aft sidestays seriously restrict each other, causing locking failure of the dual-sidestay landing gear. The singular points of two sidestays can be optimized to be approximately identical, making their movements more coordinated.

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An isogeometric analysis based design of highly sensitive and precise omnidirectional piezoelectric-fiber accelerometer

Journal of Intelligent Material Systems and Structures ◽

10.1177/1045389x20959462 ◽

2020 ◽

pp. 1045389X2095946

Author(s):

Yan Wang ◽

Jian Zhao ◽

Yang Xia ◽

Pengbo Liu ◽

Bin Tang

Keyword(s):

Isogeometric Analysis ◽

Low Frequency ◽

Optimization Procedure ◽

High Sensitivity ◽

Optimization Method ◽

Induced Voltage ◽

The Finite Element Method ◽

Highly Sensitive ◽

Cross Axis ◽

Piezoelectric Fiber

Measuring omnidirectional acceleration is highly important for robust control of the vehicle states. A novel omnidirectional accelerometer with three piezoelectric curved-fibers is designed by using the genetic algorithm based optimization method. The isogeometric analysis (IGA) is utilized to analyze the strain induced voltage outputs of curved piezoelectric fibers, which can also guarantee high computation accuracy and significantly reduce the amounts of calculation in the optimization procedure compared to the finite element method. Employing cylindrical piezoelectric three fibers, the cross-axis sensitivities of the x and z axes of the omnidirectional accelerometer is eliminated completely in theory, which ensures the detection precision of magnitude and direction of 3D acceleration. The output voltages of proposed curved three-fiber accelerometer in x and y axes respective are higher than the fully decoupled accelerometer with three orthogonal fibers. The sensor also exhibits high sensitivity in very low frequency range of [0.01 Hz, 5 Hz], and numerical simulated sensitivity can reach 7.42 to 13.41 V/g, which is 78% to 155% higher than that of the omnidirectional accelerometer with three parallel straight-fibers.

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Design and Optimization of 1.55 μm AlGaInAs MQW Polarization Mode Controllers

Photonics ◽

10.3390/photonics8100422 ◽

2021 ◽

Vol 8 (10) ◽

pp. 422

Author(s):

Xiao Sun ◽

Shengwei Ye ◽

Bocang Qiu ◽

Jichuan Xiong ◽

Xuefeng Liu ◽

...

Keyword(s):

Quantum Well ◽

Bulk Material ◽

Structural Parameters ◽

Low Cost ◽

Ridge Waveguide ◽

Polarization Mode ◽

The Finite Element Method ◽

Design And Optimization ◽

Waveguide Width ◽

Birefringence Effect

A 1.55 μm AlGaInAs multi-quantum-well (MQW) ridge waveguide polarization mode controller (PMC) is proposed. The design is based on an asymmetric half-ridge waveguide structure in which the ridge is shallow etched on one side and has a deeply etched mesa structure on the other side. The Finite-Element Method (FEM) was used to simulate the PMC and optimize its structural parameters comprehensively. Furthermore, the fabrication tolerances were also investigated in detail. The optimized PMC has a polarization conversion efficiency (PCE) of around 92.5% with a half-beat length of 1250 μm. When the PMC length was fixed at 1250 μm, to achieve a PCE derivation less than 8%, the tolerances for the ridge waveguide width and shallow etch height were 1.60 μm to 1.65 μm and 2.13 μm to 2.18 μm, respectively. In order to reduce interband gap absorption loss, the quantum well intermixing (QWI) technique was used in the model to realize a blueshift (200 nm) in the PMC. QWI is a simple, flexible, and low-cost technique for fabricating a PMC integrated with a laser diode and reduces parasitic reflections, which would otherwise degrade the overall performance. QWI also eliminates MQW material anisotropy and alleviates the birefringence effect without the need for regrowth, achieving nearly uniform properties as a bulk material.

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Integrating high-performing electrochemical transducers in lateral flow assay

Analytical and Bioanalytical Chemistry ◽

10.1007/s00216-021-03301-y ◽

2021 ◽

Author(s):

Antonia Perju ◽

Nongnoot Wongkaew

Keyword(s):

High Performance ◽

Point Of Care ◽

Low Cost ◽

High Sensitivity ◽

Lateral Flow ◽

Analytical Performance ◽

Label Free ◽

High Performing ◽

Lateral Flow Assays ◽

Electrochemical Transducers

AbstractLateral flow assays (LFAs) are the best-performing and best-known point-of-care tests worldwide. Over the last decade, they have experienced an increasing interest by researchers towards improving their analytical performance while maintaining their robust assay platform. Commercially, visual and optical detection strategies dominate, but it is especially the research on integrating electrochemical (EC) approaches that may have a chance to significantly improve an LFA’s performance that is needed in order to detect analytes reliably at lower concentrations than currently possible. In fact, EC-LFAs offer advantages in terms of quantitative determination, low-cost, high sensitivity, and even simple, label-free strategies. Here, the various configurations of EC-LFAs published are summarized and critically evaluated. In short, most of them rely on applying conventional transducers, e.g., screen-printed electrode, to ensure reliability of the assay, and additional advances are afforded by the beneficial features of nanomaterials. It is predicted that these will be further implemented in EC-LFAs as high-performance transducers. Considering the low cost of point-of-care devices, it becomes even more important to also identify strategies that efficiently integrate nanomaterials into EC-LFAs in a high-throughput manner while maintaining their favorable analytical performance.

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High Sensitivity Plasmonic Sensor Based on Fano Resonance with Inverted U-Shaped Resonator

Sensors ◽

10.3390/s21041164 ◽

2021 ◽

Vol 21 (4) ◽

pp. 1164

Author(s):

Gongli Xiao ◽

Yanping Xu ◽

Hongyan Yang ◽

Zetao Ou ◽

Jianyun Chen ◽

...

Keyword(s):

Fano Resonance ◽

Figure Of Merit ◽

High Sensitivity ◽

Refractive Index Sensor ◽

Multimode Interference ◽

Geometrical Parameters ◽

The Finite Element Method ◽

Plasmonic Sensor ◽

Coupled Mode ◽

Plasmonic Nanosensor

Herein, we propose a tunable plasmonic sensor with Fano resonators in an inverted U-shaped resonator. By manipulating the sharp asymmetric Fano resonance peaks, a high-sensitivity refractive index sensor can be realized. Using the multimode interference coupled-mode theory and the finite element method, we numerically simulate the influences of geometrical parameters on the plasmonic sensor. Optimizing the structure parameters, we can achieve a high plasmonic sensor with the maximum sensitivity for 840 nm/RIUand figure of merit for 3.9 × 105. The research results provide a reliable theoretical basis for designing high sensitivity to the next generation plasmonic nanosensor.

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60–700 K CTAT and PTAT Temperature Sensors with 4H-SiC Schottky Diodes

Sensors ◽

10.3390/s21030942 ◽

2021 ◽

Vol 21 (3) ◽

pp. 942

Author(s):

Razvan Pascu ◽

Gheorghe Pristavu ◽

Gheorghe Brezeanu ◽

Florin Draghici ◽

Philippe Godignon ◽

...

Keyword(s):

Low Cost ◽

Schottky Diodes ◽

Schottky Contact ◽

High Sensitivity ◽

Xrd Analysis ◽

Absolute Temperature ◽

Lower Sensitivity ◽

Readout Circuit ◽

Sensing Element ◽

High Performing

A SiC Schottky dual-diode temperature-sensing element, suitable for both complementary variation of VF with absolute temperature (CTAT) and differential proportional to absolute temperature (PTAT) sensors, is demonstrated over 60–700 K, currently the widest range reported. The structure’s layout places the two identical diodes in close, symmetrical proximity. A stable and high-barrier Schottky contact based on Ni, annealed at 750 °C, is used. XRD analysis evinced the even distribution of Ni2Si over the entire Schottky contact area. Forward measurements in the 60–700 K range indicate nearly identical characteristics for the dual-diodes, with only minor inhomogeneity. Our parallel diode (p-diode) model is used to parameterize experimental curves and evaluate sensing performances over this far-reaching domain. High sensitivity, upwards of 2.32 mV/K, is obtained, with satisfactory linearity (R2 reaching 99.80%) for the CTAT sensor, even down to 60 K. The PTAT differential version boasts increased linearity, up to 99.95%. The lower sensitivity is, in this case, compensated by using a high-performing, low-cost readout circuit, leading to a peak 14.91 mV/K, without influencing linearity.

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