Temperature Sensitivity of Angular Gain in Micro Rate-Integrating Gyroscopes (Mrig)

This paper provides a study on temperature sensitivity of angular gain and its correlation with effectiveness of quadrature control in Micro-Rate-Integrating Gyroscopes (MRIG). As a result of Temperature Coefficient of Frequency (TCF)-mismatch in the mechanical element of MRIG, temperature variations affect the sensitivity in direct angle measurements (i.e., angular gain). In our study using a Dual Foucault Pendulum (DFP) micro-gyroscope as a testbed, we experimentally demonstrated that Angular-Gain-Temperature-Sensitivity (AGTS) is coupled to effectiveness of the quadrature feedback controller that is implemented to compensate for anisoelasticity. For the DFP gyroscope, with a TCF-mismatch on the order of 603 ppb/°C, the angular gain variation was measured to be on the order of 820 ppm for temperatures ranging from 17 °C to 45 °C. We implemented a Dynamic Quadrature Compensator (DQC), which reduced AGTS by 63-times, down to 13 ppm. The results of this paper demonstrated feasibility of using MEMS devices as MRIG and provided a mitigation strategy to achieve an increased angular gain stability, despite a TCF-mismatch in the sensing element.