College of Advanced Interdisciplinary Studies, National University of Defense Technology, Changsha 410073, China.
Shanghai Aerospace Control Technology Institute, Shanghai 201100, China.
Sensors (Basel). 2020 Jan 5;20(1):295. doi: 10.3390/s20010295.
The Coriolis Vibratory Gyroscopes are a type of sensors that measure angular velocities through the Coriolis effect. The resonator is the critical component of the CVGs, the vibrational characteristics of which, including the resonant frequency, frequency mismatch, Q factor, and Q factor asymmetry, have a great influence on the performance of CVG. The frequency mismatch and Q factor of the resonator, in particular, directly determine the precision and drift characteristics of the gyroscope. Although the frequency mismatch and Q factor are natural properties of the resonator, they can change with external conditions, such as temperature, pressure, and external forces. In this paper, the influence of electrostatic forces on the vibrational characteristics of the fused silica cylindrical resonator is investigated. Experiments were performed on a fused silica cylindrical resonator coated with Cr/Au films. It was shown that the resonant frequency, frequency mismatch, and the decay time slightly decreased with electrostatic forces, while the decay time split increased. Lower capacitive gaps and larger applied voltages resulted in lower frequency mismatch and lower decay time. This phenomenon was theoretically analyzed, and the variation trends of results were consistent with the theoretical analysis. This study indicates that, for fused silica cylindrical resonator with electrostatic transduction, the electrostatic influence on the Q factor and frequency, although small, should be considered when designing the capacitive gap and choosing bias voltages.
科里奥利振动陀螺仪是一种通过科里奥利效应测量角速度的传感器。谐振器是 CVG 的关键组成部分，其振动特性，包括谐振频率、频率失配、Q 因子和 Q 因子不对称性，对 CVG 的性能有很大影响。特别是谐振器的频率失配和 Q 因子直接决定了陀螺仪的精度和漂移特性。尽管频率失配和 Q 因子是谐振器的固有特性，但它们会随着外部条件（如温度、压力和外力）而变化。本文研究了静电对熔融石英圆柱谐振器振动特性的影响。对涂有 Cr/Au 薄膜的熔融石英圆柱谐振器进行了实验研究。结果表明，随着静电的增加，谐振频率、频率失配和衰减时间略有减小，而衰减时间分裂增加。较小的电容间隙和较大的施加电压导致较低的频率失配和较短的衰减时间。这一现象从理论上进行了分析，结果的变化趋势与理论分析一致。本研究表明，对于具有静电转换的熔融石英圆柱谐振器，在设计电容间隙和选择偏置电压时，尽管静电对 Q 因子和频率的影响很小，但也应予以考虑。
