Naučno-tehničeskij Vestnik Informacionnyh Tehnologij, Mehaniki i Optiki (Feb 2024)
Providing operating modes for Coriolis vibration gyroscopes with low-Q resonators
Abstract
Coriolis vibration gyroscopes are a class of promising inertial primary information sensors that respond to the rotation of the resonator base through Coriolis inertial forces arising in the vibrating shell. Currently, two directions for the production of resonators for such gyroscopes have been developed: from quartz glass, a material with extremely low internal friction, and based on the processing of a metal alloy. When using the first direction, thanks to the high quality factor of quartz, it is possible to create navigation-class integrating gyroscopes. Existing samples of Coriolis vibration gyroscopes with metal resonators, as a rule, are angular velocity sensors. The problem of creating an integrating mode of a gyroscope with a metal resonator is associated with the low quality factor of metal alloys which usually does not exceed 35,000. With this value of quality factor, the duration of operation of the gyroscope in the angular deviation sensor mode will be several seconds. The paper presents methods for ensuring the functioning of Coriolis vibration gyroscopes, including the integrating gyroscope mode. A mathematical description of Coriolis vibration gyroscopes with a cylindrical cavity resonator is given based on the dynamic model of Dr. D. Lynch using the method of envelope amplitudes of oscillations. The mathematical model is supplemented with corrections that provide compensation for the dissipation of the resonator oscillations energy to implement the integrating mode of the gyroscope. The conditions for complete compensation of vibration energy dissipation are shown. A description of methods for exciting a standing wave in a resonator using periodic forcing and by creating self-oscillations is presented. It is shown that the duration of the transient excitation process is determined by the time constant of the resonator. The results of experimental studies of Coriolis vibration gyroscopes with a low-Q metal resonator are presented confirming the possibility of implementing an integrating mode of operation of the gyroscope. The initial excitation of the resonator oscillations is carried out by a self-oscillating circuit. According to the results of experimental studies, the quality factor of the metal resonator was increased by a factor of 17. The operating time of Coriolis vibrating gyroscopes has been equally increased. The possibility of constructing Coriolis vibration gyroscopes in the integrating gyroscope mode based on a low-Q metal resonator has been shown theoretically and experimentally. The solution to this problem was based on a circuitry method for increasing the quality factor. In principle, the quality factor of the resonator can be significantly increased compared to the figure achieved in the experiment. This will ensure a longer operating time of Coriolis vibration gyroscopes in the integrating mode.
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