Double-axis surface acoustic wave angular rate sensor

Abstract

The invention discloses a double-axis surface acoustic wave angular rate sensor. The sensor is composed of a piezoelectric substrate and four surface acoustic wave delay lines disposed on the surfaceof the piezoelectric substrate. The structures of the first and the third surface acoustic wave delay lines are identical and are arranged in reverse and in parallel. The structures of the second andthe fourth surface acoustic wave delay lines are identical and are arranged in reverse and in parallel, and are distributed perpendicular to the first and the third surface acoustic wave delay lines.Metal grid arrays are distributed between input transducers and output transducers of the four surface acoustic wave delay lines. The first and third surface acoustic wave delay lines form a differential sensing structure so as to detect rotation angular rate along the y-axis direction. The second and the fourth surface acoustic wave delay lines form a differential sensing structure so as to detect rotation angular rate along the x-axis direction. When the sensor rotates at a specific angular rate, the metal grid arrays are subjected to Coriolis force effect and then the spread phase speed ofthe surface acoustic waves change. Therefore, detection of the angular rate is realized.

Description

technical field [0001] The invention relates to a surface acoustic wave angular rate sensor, in particular to a surface acoustic wave angular rate sensor based on a distributed metal grid array in a biaxial traveling wave mode. Background technique [0002] At present, the angular rate sensors used in the market mainly include laser type, optical fiber type, electrostatic type and MEMS vibration type, etc., but their application in the military field is limited due to defects such as large size, high cost or poor vibration resistance. [0003] The surface acoustic wave (SAW) angular rate sensor in the traveling wave mode is mainly based on the SAW gyro effect: the rotation vector perpendicular to the propagation direction of the sound wave excites a pseudo sound wave with a certain phase difference through the Coriolis force and is connected to the initial sound surface The waves are coupled with each other, which causes the phase velocity of sound wave propagation to change...

AI Technical Summary

Problems solved by technology

The SAW angular rate sensor of this structure uses the metal lattice on the sound propagation path to improve the detection sensitivity performance of the sensor, but due to the size limitation of the metal lattice, it is difficult to make its thickness enough to increase the SAW gyro effect intensity to Degree to which practical needs are met

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