Challenges in Implementing Pitch/Roll Rate Integrating Gyroscopes: A Case Study on a New Dynamically Balanced Dual-Mass Resonator

A case study on a new dynamically balanced dual-mass resonator, for implementation in pitch/roll rate integrating gyroscopes (RIGs), is reported in this article. Proper measures have been taken during structural design to minimize the mismatch of both the resonant frequencies and the {Q} -factors between in-plane (IP) and out-of-plane (OOP) modes. To improve the {Q} -factor of OOP mode, which is generally significantly lower than that of IP mode, a dual-mass structure reduces the torque applied to the supporting substrate in the OOP mode. Thus, dominant loss mechanisms are thermoelastic dissipation (TED) and squeeze film damping (SFD). After optimizing design parameters, {Q} -factor machining can be achieved by tuning SFD by operation pressure. The designed microelectromechanical systems (MEMS) resonator was fabricated using two layers of Si substrate combined with Au-Au thermocompression bonding technology. The experimental characterization revealed that the mismatches of resonant frequencies and {Q} -factors were as small as 1.3% and 32%, respectively.