scholarly journals A Novel Method for Estimating and Balancing the Second Harmonic Error of Cylindrical Fused Silica Resonators

Micromachines ◽  
2021 ◽  
Vol 12 (4) ◽  
pp. 380
Author(s):  
Yunfeng Tao ◽  
Yao Pan ◽  
Jianping Liu ◽  
Yonglei Jia ◽  
Kaiyong Yang ◽  
...  
Keyword(s):  
Simulation Analysis ◽  
Second Harmonic ◽  
Low Frequency ◽  
Fused Silica ◽  
Cylindrical Resonator ◽  
Bias Drift ◽  
Good Consistency ◽  
Manufacturing Errors ◽  
Frequency Split ◽  
Novel Method

The cylindrical resonator gyroscope (CRG) is a type of Coriolis vibratory gyroscope which measures the angular velocity or angle through the precession of the elastic wave of the cylindrical resonator. The cylindrical fused silica resonator is an essential component of the CRG, the symmetry of which determines the bias drift and vibration stability of the gyroscope. The manufacturing errors breaking the symmetry of the resonator are usually described by Fourier series, and most studies are only focusing on analyzing and reducing the fourth harmonic error, the main error source of bias drift. The second harmonic error also is one of the obstacles for CRG towards high precision. Therefore, this paper provides a chemical method to evaluate and balance the second harmonic error of cylindrical fused silica resonators. The relation between the frequency split of the n = 1 mode and the second harmonic error of the resonator is obtained. Simulations are performed to analyze the effects of the first three harmonic errors on the frequency splits. The relation between the location of the low-frequency axis of n = 1 mode and the heavy axis of the second harmonic error is also analyzed by simulation. Chemical balancing experiments on two fused silica resonators demonstrate the feasibility of this balancing procedure, and show good consistency with theoretical and simulation analysis. The second harmonic error of the two resonators is reduced by 86.6% and 79.8%, respectively.

scholarly journals Design and Analysis of Two Piezoelectric Cymbal Transducers with Metal Ring and Add Mass

Sensors ◽  
2019 ◽  
Vol 19 (1) ◽  
pp. 137 ◽  
Author(s):  
Wenjie Wang ◽  
Weihao Shi ◽  
Peter Thomas ◽  
Mingsui Yang
Keyword(s):  
Simulation Analysis ◽  
Low Frequency ◽  
High Strength ◽  
Structural Parameter ◽  
Metal Ring ◽  
Cavity Structure ◽  
Good Consistency ◽  
Frequency Transducer ◽  
Detailed Simulation ◽  
Transducer Design

Based on traditional sandwich structure, two piezoelectric transducers were designed to meet the strict underwater application backgrounds such as high pressure, corrosion resistance, and high strength. Both transducers integrated most of previous researches while one transducer has a multilayer cavity structure which is different from the other structure and previous transducer structures. After a detailed simulation analysis of every structural parameter, key parameters were pointed out to have an obvious influence on its performance. Then, two models were constructed and compared with chosen sets of geometry parameters and manufacturing process, which can also provide a reference for low-frequency transducer design. The simulation results and experimental results of our transducers show a good consistency which indicates the cavity structure can reduce the resonance frequency.

scholarly journals Trimming of Imperfect Cylindrical Fused Silica Resonators by Chemical Etching

Sensors ◽  
2019 ◽  
Vol 19 (16) ◽  
pp. 3596 ◽  
Author(s):  
Yunfeng Tao ◽  
Yao Pan ◽  
Shilong Jin ◽  
Yonglei Jia ◽  
Kaiyong Yang ◽  
...  
Keyword(s):  
Experimental Data ◽  
Solid State ◽  
Theoretical Calculation ◽  
Material Properties ◽  
Chemical Etching ◽  
Fused Silica ◽  
Cylindrical Resonator ◽  
Frequency Split ◽  
Frequency Trimming ◽  
Stiffness Distribution

The cylindrical resonator gyroscope (CRG) is a kind of solid-state gyroscope with a wide application market. The cylindrical resonator is the key component of CRG, whose quality factor and symmetry will directly affect the performance of the gyroscope. Due to the material properties and fabrication limitations, the actual resonator always has some defects. Therefore, frequency trimming, i.e., altering the local mass or stiffness distribution by certain methods, is needed to improve the overall symmetry of the resonator. In this paper, we made further derivation based on the chemical trimming theory proposed by Basarab et al. We built up the relation between the frequency split and the balanced mass to determine the mass to be removed. Chemical trimming experiments were conducted on three cylindrical fused silica resonators. The frequency splits of the three resonators were around 0.05 Hz after chemical trimming. The relation between frequency split and balanced mass established from experimental data was consistent with the theoretical calculation. Therefore, frequency split can be reduced to lower than 0.05 Hz under rigorous theoretical calculation and optimized chemical trimming parameters.

scholarly journals Optical and Electrical Method Characterizing the Dynamic Behavior of the Fused Silica Cylindrical Resonator

Sensors ◽  
2019 ◽  
Vol 19 (13) ◽  
pp. 2928 ◽  
Author(s):  
Zhinan Qiu ◽  
Tianliang Qu ◽  
Yao Pan ◽  
Yonglei Jia ◽  
Zhenfang Fan ◽  
...  
Keyword(s):  
Dynamic Behavior ◽  
Optical Method ◽  
Laser Doppler Vibrometer ◽  
Fused Silica ◽  
Optical Methods ◽  
Q Factor ◽  
Cylindrical Resonator ◽  
Electrical Method ◽  
Frequency Split ◽  
Measurement Efficiency

Fused silica cylindrical resonant gyroscope (CRG) is a novel high-precision solid-wave gyroscope, whose performance is primarily determined by the cylindrical resonator’s frequency split and quality factor (Q factor). The laser Doppler vibrometer (LDV) is extensively used to measure the dynamic behavior of fused silica cylindrical resonators. An electrical method was proposed to characterize the dynamic behavior of the cylindrical resonator to enhance the measurement efficiency and decrease the equipment cost. With the data acquisition system and the designed signal analysis program based on LabVIEW software, the dynamic behavior of the fused silica cylindrical resonator can be analyzed automatically and quickly. We compared all the electrical measurement results with the optical detection by LDV, demonstrating that the fast Fourier transform (FFT) result of the resonant frequency measured by the electrical method was 0.12 Hz higher than that with the optical method. Thus, the frequency split measured by the electrical and optical methods was the same in 0.18 Hz, and the measurement of the Q factor was basically the same in 730,000. We conducted all measurements under the same operation condition, and the optical method was used as a reference, demonstrating that the electrical method could characterize the dynamic behavior of the fused silica cylindrical resonator and enhance the measurement efficiency.

scholarly journals Posturography with head movements in the assessment of balance in chronic unilateral vestibular lesions

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Magdalena Janc ◽  
Mariola Sliwinska-Kowalska ◽  
Piotr Politanski ◽  
Marek Kaminski ◽  
Magdalena Jozefowicz-Korczynska ◽  
...  
Keyword(s):  
High Reliability ◽  
Low Frequency ◽  
Random Order ◽  
Head Movements ◽  
Canal Paresis ◽  
Eyes Closed ◽  
Static Posturography ◽  
Unstable Surface ◽  
Novel Method ◽  
The One

AbstractThe aim of our study was to validate the method of head-shake static posturography (HS-posturography) in healthy individuals and to establish the value of this novel method in the diagnostics of patients with unilateral vestibular lesion (UV). The study included 202 participants divided into two groups, one consisting of 133 patients with canal paresis CP > 19% and one of 69 healthy subjects. Participant was tested according to the standard protocol of static posturography (SP), and with head movements of 0.3 Hz (HS 40), 0.6 Hz (HS 70) in random order controlled by a metronome. HS-posturography revealed a similar repeatability and internal consistency as the standard posturography. In patients with UV, 4th condition revealed higher sensitivity (74%) and specificity (71%) in HS 40 than in the standard posturography (67%, 65% respectively) and HS 70 (54%, 70% respectively). Static posturography and HS- posturography revealed a high reliability of the testing method. The head movements added to static posturography improve the sensitivity and specificity of the method in group with vestibular impairment. The most important test for that purpose seems to be the one on unstable surface with the eyes closed, with low frequency of head movements.

scholarly journals A Molecular Architectural Approach to Second-Order Nonlinear Optical Materials

1995 ◽  
Vol 392 ◽  
Author(s):  
Xiaoguang Yang ◽  
Duncan McBranch ◽  
Basil Swanson ◽  
Dequan Li
Keyword(s):  
Nonlinear Optical ◽  
Second Harmonic ◽  
Fused Silica ◽  
Second Order ◽  
Nonlinear Susceptibility ◽  
Design And Synthesis ◽  
Fundamental Wavelength ◽  
Assembled Monolayers ◽  
Methylene Groups ◽  
Nlo Chromophores

AbstractThe design and synthesis of a family of calix[4]arene-based nonlinear optical (NLO) chromophores are discussed. The calixarene chromophores are macrocyclic compounds consisting of four simple D-π-A units bridged by methylene groups. These molecules were synthesized such that four D-π-A units of the calix[4]arene were aligned along the same direction with the calixarene in a cone conformation. These nonlinear optical super-chromophores were subsequently fabricated into covalently bound self-assembled monolayers on the surfaces of fused silica and silicon. Spectroscopic second harmonic generation (SHG) measurements were carried out to determine the absolute value of the dominant element of the second-order nonlinear susceptibility, d33, and the average molecular alignment, ψ. We find a value of d33 = 60 pm/V at a fundamental wavelength of 890 nm, and ψ˜ 36° with respect to the surface normal.

Simulation Analysis of the Working Process of the Corn Seed Metering Device with Combination Inner-Cell

2012 ◽  
Vol 215-216 ◽  
pp. 160-167 ◽  
Author(s):  
Qing Long Li ◽  
Ji Yang Yu ◽  
Qiang Qiang Zhang ◽  
Jian Qun Yu ◽  
Hong Fu
Keyword(s):  
Simulation Analysis ◽  
Three Dimensional ◽  
Bench Test ◽  
Particle Model ◽  
Test Results ◽  
Working Process ◽  
Corn Seed ◽  
3D Cad ◽  
Novel Method ◽  
Seed Metering Device

A three-dimensional discrete element method analytic model of the corn seed metering device with combination inner-cell was established based on its 3D CAD model, and the three-dimensional particle model of corn seeds was built by using the method of combination spherical particle. The working process of the corn seed metering device was simulated and analyzed by self-developed three-dimensional CAE software. It was observed that the simulative results of the seeding performance, clearing angles and dropping angles of the corn seeds well agreed with the bench test results. A novel method for studying and designing of the corn seed metering device was put forward.

Low Temperature Fabrication and Surface Modification Methods for Fused Silica Micro- and Nanochannels

2014 ◽  
Vol 1659 ◽  
pp. 15-26
Author(s):  
Sumita Pennathur ◽  
Pete Crisalli
Keyword(s):  
Low Temperature ◽  
Surface Properties ◽  
Fused Silica ◽  
Microfluidic Channels ◽  
Metal Electrodes ◽  
Release Channel ◽  
Nanofluidic Channels ◽  
Novel Method ◽  
Electronic Sensing ◽  
Release Method

ABSTRACTElectrokinetic based micro- and nanofluidic technologies provide revolutionary opportunities to separate, identify and analyze biomolecular species. Key to fully harnessing the power of such systems is the development of a robust method for integrated electrodes as well as a thorough understanding of the influence of the electrokinetic surface properties with and without different surface modifications. In this work, we demonstrate a surface micromachined fabrication approach for integrated addressable metal electrodes within centimeter-long nanofluidic channels using a low-temperature, xenon diflouride dry-release method for novel biosensing applications, as well as recent results from a joint theoretical and experimental study of electrokinetic surface properties in nano- and microfluidic channels fabricated with fused silica. The main contribution of this fabrication process involves the addition of addressable electrodes to a novel dry-release channel fabrication method, produced at <300°C, to be used in nanofluidic electronic sensing of biomolecules. Finally, we also show a novel method with which to coat our channels with silane based chemistries. Certain modifications are observed to show improved resistance to non-specific adhesion of both small molecules and proteins, indicating their further use as compatible surfaces in micro- and nanofluidic applications.

The Structural Properties Research of Piezoelectric Cantilever Beam Based on Vehicular Environment

2014 ◽  
Vol 525 ◽  
pp. 342-345
Author(s):  
Yan Zhao ◽  
Shan Shan Liu ◽  
Yu Feng Li
Keyword(s):  
Cantilever Beam ◽  
Simulation Analysis ◽  
Low Frequency ◽  
Electrical Energy ◽  
Body Vibration ◽  
Low Frequency Vibration ◽  
Generating Capacity ◽  
Nature Frequency ◽  
Beam Parameters ◽  
Vibration Simulation

The piezoelectric power generating device can convert the vibration energy into electrical energy in vehicular environment. So it can provide energy for electronic components. Firstly, the mathematical model of road-vehicles-piezoelectric device coupled vibration was established under the random road excitation. Then vibration simulation analysis of the established model was made. The acceleration and spectrum of the vehicles body and its connection with the suspension were researched under B-class. The car body vibration is low-frequency vibration. Further studies shows that expanding the speed range and changing the roads level almost have no effect on the natural frequency of vehicles body vibration. Secondly, in order to make the maximum generating capacity, the influences of cantilever beam parameters have on its nature frequency were researched. The research results provide basis for parameters design in cantilever beam.

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