Study On Resonance Characteristics Of Hemispherical Harmonic Oscillator

The Hemispherical Resonator Gyroscope(HRG)is a new type of solid-state gyroscope that does not require traditional rotors.It measures the angular rate of an external carrier by utilizing the standing wave precession effect generated by the external vibration of its hemispherical lip surface.It has broad application prospects in aviation and military fields.The traditional "three-component" hemispherical resonator gyroscopes have been partially used in China,but mass production of the gyroscopes is limited due to complex manufacturing processes and high precision assembly requirements.The two-component hemispherical resonator gyroscopes have advantages such as simple structure,stable performance,high reliability,and easy maintenance,making them a research hotspot.Based on the above background,the main research contents and conclusion of the two-component hemispherical resonator gyroscope as follows.(1)The working modes and operating modes of the hemispherical resonator are determined.Based on the study of different vibration modes of the resonator and a comparison of the advantages and disadvantages of different resonant modes,the second-order resonant mode is determined as the working mode of the resonator in this paper.The motion equation of the resonator is derived based on the thin shell elasticity theory,providing a theoretical basis for the design and control of the two-component hemispherical resonator gyroscope system.Finally,by comparing the two main operating modes of the resonator,the force balance mode is chosen as the operating mode.(2)A control scheme for the two-component hemispherical resonator gyroscope is proposed based on capacitive detection using parallel plate electrodes and electrostatic force driving.Firstly,based on the working requirements of the hemispherical resonator gyroscope,the configuration of the base electrodes is determined,and the detection principle of the two-component hemispherical resonator gyroscope’s output signal using planar electrodes as the core is proposed.Then,by analyzing the steady-state and transient characteristics of the parallel plate capacitor,the control of the output signal and the improvement of the sensitivity of detecting capacitance variations are discussed.(3)A simulation model based on a phase-locked loop for the full-loop control of the two-component hemispherical resonator gyroscope is established,and the variation process of parameters such as the stabilization time,stabilization amplitude,and phase error of the gyroscope’s output signal in the closed-loop system is analyzed.A lock-in loop control system based on low-pass filters,PID controllers,and voltage-controlled oscillators is established using Simulink simulation software.It achieves stable control of the amplitude and phase of the hemispherical resonator gyroscope’s resonant output signal,and the evolution of the gyroscope’s output signal in the closed-loop system is studied.(4)The peripheral circuits of the hemispherical resonator gyroscope are designed.In-depth research and optimization design are conducted on the unit circuits that affect the performance indicators of the gyroscope,such as the signal readout circuit,excitation circuit,and power supply circuit of the hemispherical resonator gyroscope.Methods to improve the stability of the detection voltage,such as weak signal processing and filtering techniques,are studied.The performance of the designed circuits is simulated using Tina-TI software,achieving a high-gain and low-noise interface circuit design.(5)The preparation and assembly of a prototype of the hemispherical resonator gyroscope are completed to verify the feasibility of the control scheme for the two-component gyroscope.The base metal electrodes of the hemispherical resonator gyroscope are prepared using magnetron sputtering,and the assembly of the two-component hemispherical resonator gyroscope is achieved through indium soldering.The peripheral circuits of the hemispherical resonator gyroscope are also prepared.Finally,based on the assembled prototype of the hemispherical resonator gyroscope and the simulated parameters,the impact of DC signals(different voltages)and AC signals(different amplitudes,different frequencies)in the excitation signal on the output signal of the hemispherical resonator gyroscope in its main resonant mode is investigated,thereby validating the correctness of the peripheral circuit design and system simulation in this study.