Novel mode-matched MEMS gyroscope with high capacity to tune frequency and Q-factor

为了提高MEMS谐振器的刚度、灵敏度和调谐能力，提出了一种新型的三质量谐振器（TMR）和具有多个验证质量的双轴对称谐振器。反相模态（ωanti）和同相模态（ωin）的频率分别与悬架和内部刚度有很强的相关性。因此，频率差可以通过悬挂刚度或内部刚度进行静电调谐。通过减小内刚度可以对幅值比进行很大程度的调节，使锚损或挤压膜阻尼相关的q因子发生显著变化，而频率ω ω的变化可以忽略不计。当通过降低两个主proof质量的悬架刚度来调谐频率ωanti时，仅观察到模态振型（即振幅比）的微小变化，从而引起q因子的微小调整。因此，在相互影响很小的情况下，频率ω抗和q因子可以独立调谐。将一种基于TMR技术的双轴对称音叉谐振器应用于QFM/RIG。两个动态等效的证明质量提供了一个平衡的动态系统，在它们之间实现了四个额外的小质量，可以独立地调谐两个反相模式的q因子，对频率的影响很小。频率主要受悬架刚度的影响，而q因子通过两个平衡质量和小质量之间的模态耦合强烈依赖于挤压膜阻尼。

This research introduces a novel triple mass resonator (TMR) and a two-axis symmetric resonator with multiple proof masses for improving stiffness sensitivity and tuning capability of MEMS res- onators. The frequencies of the anti-phase (ωanti) and in-phase (ωin) modes have a strong dependency on the suspension and inner stiffness, respectively. Therefore the frequency difference can be electro- statically tuned by either suspension stiffness nor inner stiffness. The amplitude ratio can be adjusted largely by decreasing the inner stiffness, which brings a significant change in Q-factor related to anchor loss or squeeze film damping, while a negligible shift in frequency ωanti. When the frequency ωanti is tuned by decreasing suspension stiffness of two main proof masses, only a slight change in the mode shape, i.e. the amplitude ratio, is observed causing a minor adjustment to Q-factor. Therefore the frequency ωanti and Q-factor can be tuned independently under a little mutual influence.A two-axis symmetric tuning fork resonator based on TMR technique is applied for QFM/RIG. Two dynamically equivalent proof masses provide a balance dynamic system and four extra-small masses is implemented in between them, which could tune the Q-factor of two anti-phase modes independently with small effect on the frequency. Frequency is mainly affected by suspension stiffness and Q-factor is strongly dependent on the squeeze film damping through the mode coupling between two balanced masses and small masses.