Characterization of the Bell-Shaped Vibratory Angular Rate Gyro

Abstract

The bell-shaped vibratory angular rate gyro (abbreviated as BVG) is a novel shell vibratory gyroscope, which is inspired by the Chinese traditional bell. It sensitizes angular velocity through the standing wave precession effect. The bell-shaped resonator is a core component of the BVG and looks like the millimeter-grade Chinese traditional bell, such as QianLong Bell and Yongle Bell. It is made of Ni43CrTi, which is a constant modulus alloy. The exciting element, control element and detection element are uniformly distributed and attached to the resonator, respectively. This work presents the design, analysis and experimentation on the BVG. It is most important to analyze the vibratory character of the bell-shaped resonator. The strain equation, internal force and the resonator's equilibrium differential equation are derived in the orthogonal curvilinear coordinate system. When the input angular velocity is existent on the sensitive axis, an analysis of the vibratory character is performed using the theory of thin shells. On this basis, the mode shape function and the simplified second order normal vibration mode dynamical equation are obtained. The coriolis coupling relationship about the primary mode and secondary mode is established. The methods of the signal processing and control loop are presented. Analyzing the impact resistance property of the bell-shaped resonator, which is compared with other shell resonators using the Finite Element Method, demonstrates that BVG has the advantage of a better impact resistance property. A reasonable means of installation and a prototypal gyro are designed. The gyroscopic effect of the BVG is characterized through experiments. Experimental results show that the BVG has not only the advantages of low cost, low power, long work life, high sensitivity, and so on, but, also, of a simple structure and a better impact resistance property for low and medium angular velocity measurements.

Analysis and compensation of mass imperfection effects on 3-D sensitive structure of bell-shaped vibratory gyro

“…The geometric parameters of the bell-shaped resonator (including shell [18] and piezoelectric electrode) are depicted in Fig. 5.…”

Research on the Signal Process of a Bell-Shaped Vibratory Angular Rate Gyro

“…It measures the input angular rate by detecting the resonator's standing wave precession under the spinning condition [6]. The structure of the bell-shaped resonator is shown in Figure 1, including the bell-shaped resonator, piezoelectric elements and the isolate hole.…”

“…The literature [5,6] gives a detailed description on the design, analysis and experimentation of the bell-shaped vibratory angular rate gyro. On that basis, the prototype gyro has been developed and has a certain accuracy.…”

A Novel Vibration Mode Testing Method for Cylindrical Resonators Based on Microphones

“…For the sake of in depth research into the drift of vibratory cylinder gyroscopes, it is necessary to accurately measure the offset of the vibration mode of the cylindrical resonator. Laser vibrometers are used to measure the vibration of one spot on the surface of the resonator, then the mode shape of the resonator can be obtained by a spot scan method [ 9 ]. Pattern angle error vs pattern angle and output of the quadrature null loop vs pattern angle are measured by the electrostatic method [ 10 ].…”