The cylindrical resonator gyroscope (CRG) is a typical Coriolis vibratory gyroscope whose performance is determined by the Q factor and frequency mismatch of the cylindrical resonator. Enhancing the Q factor is crucial for improving the rate sensitivity and noise performance of the CRG. In this paper, for the first time, a monolithic cylindrical fused silica resonator with a Q factor approaching 8 × 10⁵ (ring-down time over 1 min) is reported. The resonator is made of fused silica with low internal friction and high isotropy, with a diameter of 25 mm and a center frequency of 3974.35 Hz. The structure of the resonator is first briefly introduced, and then the experimental non-contact characterization method is presented. In addition, the post-fabrication experimental procedure of Q factor improvement, including chemical and thermal treatment, is demonstrated. The Q factor improvement by both treatments is compared and the primary loss mechanism is analyzed. To the best of our knowledge, the work presented in this paper represents the highest reported Q factor for a cylindrical resonator. The proposed monolithic cylindrical fused silica resonator may enable high performance inertial sensing with standard manufacturing process and simple post-fabrication treatment.

The hemispherical resonator gyroscope (HRG) has attracted the interest of the world inertial navigation community because of its exceptional performance, ultra-high reliability and its potential to be miniaturized. These devices achieve their best performance when the differences in the frequencies of the two degenerate working modes are eliminated. Mechanical treatment, laser ablation, ion-beams etching, etc., have all been applied for the frequency tuning of resonators, however, they either require costly equipment and procedures, or alter the quality factors of the resonators significantly. In this paper, we experimentally investigated for the first time the use of a chemical etching procedure to decrease the frequency splits of hemispherical resonators. We provide a theoretical analysis of the chemical etching procedure, as well as the relation between frequency splits and mass errors. Then we demonstrate that the frequency split could be decreased to below 0.05 Hz by the proposed chemical etching procedure. Results also showed that the chemical etching method caused no damage to the quality factors. Compared with other tuning methods, the chemical etching method is convenient to implement, requiring less time and labor input. It can be regarded as an effective trimming method for obtaining medium accuracy hemispherical resonator gyroscopes.

In this paper, an adjustable magnetic switch (AMS) based on splice winding is investigated numerically and experimentally. The proposed AMS has advantage of high power level, high repetitive rate capability, long lifetime achievability, and electrical parameters tunability, which meets the growing requirements of the military and industrial application of pulsed power technology. Adjustment of the electrical parameters of magnetic switch is achieved by altering the number of windings via the modification of the joint points between the AMS and the main circuit. Specifically, basic principle of the AMS is analyzed based on characteristics of the magnetic switch. Detailed design considerations are described for achieving modification of the winding's number ranging from 1 to M (positive integer larger than 1), which is limited by the insulation density, easily and reliably. In order to verify the design, two typical electrical parameters of an AMS are numerically calculated and simulated by the circuit simulation software. Accordingly, a test experiment platform was setup in our laboratory and the primary experimental study demonstrates that the AMS can successfully alter the electrical parameters with results similar to the calculation. A typical (1 - cos ωt) pulse with rise times of 4 and 5 μs, a peak voltage of approximately 20 kV, and a peak current of over 1.0 kA was achieved on the capacitor load. The experimental results show reasonable agreement with the theoretical and numerical analyses.

During hemispherical resonator gyroscope (HRG) packaging, localized high temperatures cause nonuniform thermal distributions and degrade the stability of key dynamic parameters. To reduce these temperature effects, the HRG thermal field was analyzed using coupled simulations in COMSOL Multiphysics. First, the mechanisms for local high temperatures were analyzed. Second, thermal simulations of getter activation and hermetic welding were performed and optimization strategies were proposed. Third, the effects of housing materials and structural dimensions were investigated to further optimize the temperature effects. Finally, dynamic parameter stability experiments were conducted to evaluate the optimization effectiveness. Compared with the original packaging process, the optimization significantly reduced the disturbance effect of the high temperature on the key dynamic parameters. Throughout packaging, the maximum quality factor (Q factor) reached 1.775 × 10⁷, the frequency split (Δf) remained below 1 mHz and the Q factor inhomogeneity (ΔQ) remained below 3.7%, indicating that the dynamic parameters of the gyroscope were well preserved. Meanwhile, the measured leak rates remained below 1 × 10⁻¹² Pa·m³/s. These results demonstrate the optimization effectively mitigates packaging-induced thermal disturbances, improving dynamic parameter stability with excellent hermeticity. This provides a reliable dynamic parameter basis for the high-performance operation of the HRG.