High Precision Assembly and Welding Method for Flat-Electrode Hemispherical Resonator Gyro

Assembly and welding of the hemispherical resonator and flat electrode are the core process links in gyro manufacturing, which will affect the electrode excitation, detect gain consistency of the hemispherical resonator gyro and the vibration performance parameters of the resonator, thus ultimately affecting the output accuracy of the gyro. To achieve a high-precision assembly and welding, first, this article establishes the assembly error model of the hemispherical resonator and flat electrode, analyzes the effect of assembly error on static capacitance, and proposes an assembly spacing measurement scheme based on static capacitors. Then, the integrated experimental platform of high-precision assembly and welding is designed and implemented, equipped with a high-precision capacitance detection circuit, and the capacitance detection circuit is calibrated using actuators. Finally, the experimental results show that the average assembly clearance between the hemispherical resonator and the flat electrode reaches $33~\mu \text{m}$ , the peak-to-peak value is less than $3~\mu \text{m}$ , and the non-uniformity of the assembly gap is less than 9.4%. In addition, to analyze the influence on the vibration parameters of the resonator after assembly and welding, a test platform for measuring the vibration performance parameters of the resonator is built. The experimental results show that the mean reduction of the quality factor of the resonator in the range of 600–1000 w after assembly and welding is less than 8.6%, which verifies the correctness of the theoretical model and the superiority of the assembly and welding scheme.