Investigation of the Measured Quality Factor Versus Polarization Voltage of a Multiple-Beam Tuning-Fork Gyroscope

2012 ◽  
Author(s):  
Peng Cheng ◽  
Yujie Zhang ◽  
Wenting Gu ◽  
Zhili Hao
Keyword(s):  
Quality Factor ◽  
Tuning Fork ◽  
Factor Versus ◽  
Mechanical Quality Factor ◽  
Thermoelastic Damping ◽  
Polarization Voltage ◽  
Multiple Beam ◽  
Mechanical Quality ◽  
Quality Factor Q ◽  
Anchor Loss

In light of the importance of the mechanical Quality factor (Q) to the ultimate performance of tuning-fork gyroscopes, this paper presents an investigation on the effect of polarization voltage on the Q of a multiple-beam tuning-fork gyroscope. An experimental study is conducted to quantify the relation of the measured Q of the gyroscope to polarization voltage. The two loss mechanisms, thermoelastic damping and anchor loss, in the device are analyzed to identify the reason behind the Q drop with polarization voltage. Using a numerical model of thermoelastic damping built upon thermal-energy method, polarization voltage is found to have a negligible effect on the Q of the gyroscope. Due to the asymmetry of the fabricated devices resulting from fabrication variations, anchor loss is identified as the cause of the Q drop with polarization voltage and an analytical model of anchor loss is further proposed to take polarization voltage into account.

An Electrostatic Torsional Microresonator With Improved Quality Factor

2010 ◽  
Author(s):  
Mohammad Amin Rasouli ◽  
Behraad Bahreyni
Keyword(s):  
Quality Factor ◽  
Structural Design ◽  
Mechanical Quality Factor ◽  
Loss Reduction ◽  
Electrostatically Actuated ◽  
Mechanical Quality ◽  
To Come ◽  
Q Factors ◽  
Quality Factor Q ◽  
Anchor Loss

In this paper, we propose two structures for electrostatically actuated torsional microresonators in order to improve their mechanical quality factor (Q). In order to attain higher Q-factors, various mechanisms that limit Q-value of microresonators are investigated. The dominant sources of energy loss were minimized through structural design considerations. Since anchor and support losses are known to be the dominant energy dissipation mechanisms for most resonators, including the torsional microresonators of this work, our main focus is to come up with design structures that lead to anchor loss reduction. Finite element analyses (FEA) were employed to verify the design principle. It is demonstrated that the results are in agreement with our expectations, validating the effectiveness of presented structures from the view point of anchor loss reduction and Q-factor boosting. To compare analytic and experimental results, the proposed structures are fabricated and will be tested.

scholarly journals A Study on the Trimming Effects on the Quality Factor of Micro-Shell Resonators Vibrating in Wineglass Modes

Micromachines ◽  
2019 ◽  
Vol 10 (10) ◽  
pp. 695
Author(s):  
Lu ◽  
Xi ◽  
Xiao ◽  
Shi ◽  
Zhuo ◽  
...  
Keyword(s):  
Finite Element Method ◽  
Quality Factor ◽  
Second Harmonic ◽  
Great Influence ◽  
Fem Simulation ◽  
Q Factor ◽  
Thermoelastic Damping ◽  
Frequency Trimming ◽  
Quality Factor Q ◽  
Anchor Loss

Frequency trimming based on mass and stiffness modification is an important post-fabrication process for micro-shell resonators (MSRs). However, the trimming effects on the quality factor are seldom studied, although they may have great influence on the performance of the resonator. This paper presents a study on the quality factor (Q-factor) variation of trimmed micro-shell resonators (MSR). Thermoelastic damping (QTED) and anchor loss (Qanchor) are found to be the dominant energy loss mechanisms resulting in the reduction of the overall Q-factor, according to finite element method (FEM). The effects of different trimming methods on QTED and Qanchor are studied here, respectively. It is found that trimming grooves ablated in the rim of the resonator can cause a ~1–10% reduction of QTED, and the length of trimming groove is positively related to the reduction of QTED. The reduction of QTED caused by the mass adding process is mainly related to the thermal expansion coefficient and density of the additive and contact area between the resonator and additive masses. Besides, the first and second harmonic errors caused by asymmetrical trimming can cause a 10–90% reduction of Qanchor. Finally, trimming experiments were conducted on different resonators and the results were compared with FEM simulation. The work presented in this paper could help to optimize the trimming process of MSRs.

scholarly journals Mechanical Quality Factor of Pb(ZrxTi 1−x) 1−y (Mg1/3Nb2/3)yO3 Solid Solution Prepared by Wet-Dry Combination Method

1999 ◽  
Vol 67 (10) ◽  
pp. 985-987
Author(s):  
Yoshiyuki ABE ◽  
Taisyu YANAGISAWA ◽  
Kazuyuki KAKEGAWA ◽  
Yoshinori SASAKI
Keyword(s):  
Solid Solution ◽  
Quality Factor ◽  
Mechanical Quality Factor ◽  
Combination Method ◽  
Mechanical Quality

A Microcontroller Approach to Measuring Transmissibility of MEMS Devices

2015 ◽  
Vol 2015 (DPC) ◽  
pp. 001564-001593
Author(s):  
Chong Li ◽  
Yixuan Wu ◽  
Haoyue Yang ◽  
Luke L. Jenkins ◽  
Robert N. Dean ◽  
...  
Keyword(s):  
Resonant Frequency ◽  
Quality Factor ◽  
Real Time ◽  
High Speed ◽  
Mechanical Quality Factor ◽  
Quantization Noise ◽  
Mems Devices ◽  
Input And Output ◽  
Mechanical Quality ◽  
Mems Device

The transmissibility reveals two very useful characteristics of a micro-electro-mechanical systems (MEMS) device, the resonant frequency and the mechanical quality factor. Real time knowledge on these two important factors can enhance application performance or avoid potential problems from environmental disturbances due to fabrication tolerances and the resulting operational differences in otherwise identical devices. Expensive laboratory equipment is typically used to measure the transmissibility. However, these test systems are not readily adaptable to field use. Therefore, it is important to be able to measure the transmissibility using a real time technique with a simplified test setup. This study proposes a technique that can compute the transmissibility in real time using a low cost microcontroller. This technique utilizes two laser vibrometers to detect the input and output motions of the proof mass in a MEMS device, which are fed to high speed 500 KHz analog to digital converters (ADC) in the microcontroller. A filtering step is performed to decrease noise. After the sampling and pre-filtering, a Fast Fourier Transform (FFT) is performed to convert the time-domain signals to frequency domain signals. The amplitude of the output signal at each frequency is divided by the amplitude of the corresponding input signal at each frequency to obtain the transmissibility. To overcome the difficulties resulting from measurement and quantization noise, a recursive calculating algorithm and a de-quantization filter are introduced. The recursive calculating process guarantees that the system updates the results continually, which results in a transmissibility plot covering the entire bandwidth. The de-quantization filter considers the validity of the data and performs the transmissibility division step accordingly. A cantilevered structure was chosen as the device-under-test to verify and evaluate this technique. The cantilevered device was attached to an electromechanical shaker system for vibratory stimulation. Two laser vibrometers were used to detect the input and output motion and this data was fed into a microcontroller. The microcontroller was STM32F407, which is 32-bit and 168 MHz controller. The tests demonstrated that this technique can measure the transmissibility and therefore the resonant frequency and mechanical quality factor accurately compared to a professional signal analyzer.

Hardening behavior and highly enhanced mechanical quality factor in (K 0.5 Na 0.5 )NbO 3 –based ceramics

2017 ◽  
Vol 37 (5) ◽  
pp. 2083-2089 ◽  
Author(s):  
Hyoung-Su Han ◽  
Jurij Koruza ◽  
Eric A. Patterson ◽  
Jan Schultheiß ◽  
Emre Erdem ◽  
...  
Keyword(s):  
Quality Factor ◽  
Mechanical Quality Factor ◽  
Hardening Behavior ◽  
Mechanical Quality
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