THERMOELASTIC DAMPING IN FLEXURAL-MODE RING GYROSCOPES

This paper provides a comprehensive derivation for thermoelastic damping (TED) in flexural-mode ring gyroscopes, in light of recent efforts to design high rateresolution gyroscopes. Imposing an upper limit on the attainable mechanical noise floor of a vibratory gyroscope, thermoelastic damping in a ring gyroscope is extracted from the equations of linear thermoelasticity. By assuming that it is small and therefore has negligible effect on the flexural-mode vibrations in a ring, thermoelastic damping manifests itself through temporal attenuation, where a complex frequency is used to quantitatively evaluate this damping. The exact solution to thermoelastic damping is derived and verified with experimental data in the literature. This work not only provides significant insight to the geometrical design in high-Q ring gyroscopes, but also defines their performance limit.

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