Triple-mode vibratory gyroscope

Abstract

Coriolis vibratory gyroscope (CVG) is one of the chronologically latest gyroscopic technologies that appeared on the world market in the 90s of the last century. This technology has spread throughout the world for a relatively short time, mainly due to its micro-miniature version based on the micro-electro-mechanical system (MEMS), the so-called MEMS gyroscopes. There are two well-known modes of Coriolis vibratory gyro operation. These are rate mode and rate-integrating modes described in many works of different authors. There is also known dual mode CVG in which two abovementioned modes of operation have been combined in one gyro with automatic switching from one mode to another. Such a dual-mode CVG gains additional advantages over competing technologies, such as laser and fiber-optic gyroscopes. Recently, differential mode of operation for single mass CVG has been developed in Ukraine. It was shown that differential mode of operation has excellent external disturbances rejection properties.This paper considers each mode of CVG operation and the questions of how to embed the differential mode into two first abovementioned ones to obtain triple-mode CVG which will widen application area and tighten position over competitive technologies. This triple-mode CVG can surely be realized in MEMS and non-MEMS gyros.Thus, the following is defined, Differential CVG can be considered as third mode of operation for vibratory gyroscopes along with two well-known rate and rate-integrating ones. Differential mode of operation can be built-in the single gyro together with the two others, rate and rate-integrating modes, to implement triple-mode CVG. Triple-mode gyro can be implemented both for MEMS and non MEMS vibratory gyros.Differential mode of operation has greater, than rate mode, external disturbances rejection factor and can be used when motion occurs in harsh environment.Realization of triple mode CVG gives it highest «versatility» in comparison with competitive gyro technologies like ring laser gyro and fiber optic one.