Analysis On The Damping Asymmetry And Compensation Methods Of Cylindrical Vibrating Gyroscope Resonators

The cylindrical resonator gyroscope,which has advantages such as high precision,low difficulty in processing,low cost and low energy consumption,has become an important research area in the solid wave gyro.The quality of cylindrical resonators is important for the gyro’s performance.Due to the asymmetric material and manufacture errors,frequency split and damping asymmetry are inevitable in the cylindrical resonators and produce tremendous negative effects.The frequency split can be removed by frequency trimming and closed-loop control but these methods can not eliminate the damping asymmetry’s influences completely.In this paper,the damping asymmetry’s basic theory and influences are investigated and it is also analyzed based on Q factor circumferential distribution.What is more,the damping asymmetry compensation method is proposed on the basis of piezoelectric electrodes’ influences on damping characteristic of cylindrical resonators.The main contents of this dissertation are as follows:1.The basic structure and operating principle of the cylindrical vibrating gyroscope are briefly introduced.The cylindrical resonators’ dynamic model and error model are established to analyze the damping asymmetry’s influences on the gyro’s performance under the open-loop mode and force-balance mode.2.The damping asymmetry are investigated based on the cylindrical resonators’ Q factor circumferential distribution.The damping asymmetry’s basic theory and its influences are introduced and the amplitude-frequency response method for measuring Q factor is analyzed at the same time.The theoretical model of cylindrical resonators is established to investigate the laws of the Q factor circumferential distribution and experiments are also designed to verify the theoretical results.What is more,the procedures of screening high-quality cylindrical resonators are also figured out in this section.3.Damping characteristic of cylindrical resonators influenced by piezoelectric electrodes has been investigated in details.The dynamical model and finite element model are established to analyze the damping characteristic influenced by piezoelectric electrodes.Then influencing laws of some parameters of the adhesive layer and piezoelectric electrodes are obtained from the simulation results.Afterwards,a series of experiments are implemented to validate the simulation results,showing that the simulation values and experimental results are in accord with each other.4.A novel compensation method of damping asymmetry for cylindrical resonators is presented based on piezoelectric electrodes.The damping asymmetry compensation model and finite element model are established to analyze this compensation method’s characteristics.Piezoelectric electrodes should be pasted on the damping axes to improve this method’s compensation efficiency.What is more,the inner edges of piezoelectric electrodes with smaller width have less damping component on another damping axis.The methods of positive trimming and negative trimming are proposed based on theoretical analysis and experiments are also implemented to validate the compensation effects.