This study presents a scheme for the identification and trimming of the first three harmonics of mass defects in micro hemispherical resonators(MHRs),aiming to refine their mass balancing techniques.Given the manufact...This study presents a scheme for the identification and trimming of the first three harmonics of mass defects in micro hemispherical resonators(MHRs),aiming to refine their mass balancing techniques.Given the manufacturing and structural uniqueness of MHRs,a multimodal elastic electrode substrate is designed to respond to the first three harmonics.Configured as cantilever beams with a load platform,this substrate forms an identification assembly with the MHR.The radial eccentric forces generated by the 1st and 3rd harmonics in the MHR can excite the swing modes of the assembly,while the axial force generated by the 2nd harmonic can induce axial mode vibrations along the Z-axis.A method is proposed to decompose the vibration information of the elastic electrode substrate into doublecycle,single-cycle,and offset components under the N=2 modes,enabling the extraction of swing mode and Z-axis translational mode response signals and the retro-calculation of the first three harmonics.Finite element simulation,based on a model of the identification assembly,validates the proposed scheme by simulating the identification and trimming process.Subsequently,an identification assembly sample is fabricated and subjected to identification and trimming of the first three harmonics using a laser vibrometer and femtosecond laser ablation process.After multiple iterations,the first three harmonics are reduced by 92.8%,89.3%,and 75.5%,respectively,effectively suppressing the swing modes and axial translation modes induced by unbalanced mass.展开更多
The quality factor(Q factor)is a crucial performance parameter for resonators.In this paper,a novel release method for highquality micro fused silica shell resonators with teeth-like tines with good surface morphology...The quality factor(Q factor)is a crucial performance parameter for resonators.In this paper,a novel release method for highquality micro fused silica shell resonators with teeth-like tines with good surface morphology is proposed.This method is based on femtosecond laser-assisted chemical etching.First,the optimal energy range of femtosecond laser modification is obtained through mechanism analysis.Second,the optimal parameters for a straight line and arc pattern are determined by optimizing the average output power,processing speed,and processing spacing.The results demonstrate why edge breakage in rounded corners is easy under different parameters.Finally,according to these conclusions,the processing is performed on a micro fused silica shell resonator with a Q factor exceeding 6 million.In addition,subsurface damage is rare throughout the fabrication process,and the surface roughness of the released cross section reaches the nanometer level.The improved Q factor helps suppress mechanical thermal noise and reduce zero bias and zero bias drift,constituting the primary method for enhancing the performance of the resonant gyroscope.展开更多
基金supported by the National Natural Science Foundation of China(62204261,51935013 and 52075540).
文摘This study presents a scheme for the identification and trimming of the first three harmonics of mass defects in micro hemispherical resonators(MHRs),aiming to refine their mass balancing techniques.Given the manufacturing and structural uniqueness of MHRs,a multimodal elastic electrode substrate is designed to respond to the first three harmonics.Configured as cantilever beams with a load platform,this substrate forms an identification assembly with the MHR.The radial eccentric forces generated by the 1st and 3rd harmonics in the MHR can excite the swing modes of the assembly,while the axial force generated by the 2nd harmonic can induce axial mode vibrations along the Z-axis.A method is proposed to decompose the vibration information of the elastic electrode substrate into doublecycle,single-cycle,and offset components under the N=2 modes,enabling the extraction of swing mode and Z-axis translational mode response signals and the retro-calculation of the first three harmonics.Finite element simulation,based on a model of the identification assembly,validates the proposed scheme by simulating the identification and trimming process.Subsequently,an identification assembly sample is fabricated and subjected to identification and trimming of the first three harmonics using a laser vibrometer and femtosecond laser ablation process.After multiple iterations,the first three harmonics are reduced by 92.8%,89.3%,and 75.5%,respectively,effectively suppressing the swing modes and axial translation modes induced by unbalanced mass.
基金supported by the National Natural Science Foundation of China Regional Innovation and Development Joint Fund Key Support Project(Grant No.U21A20505)the National Natural Science Foundation of China(Grant Nos.62204261 and 52205613)。
文摘The quality factor(Q factor)is a crucial performance parameter for resonators.In this paper,a novel release method for highquality micro fused silica shell resonators with teeth-like tines with good surface morphology is proposed.This method is based on femtosecond laser-assisted chemical etching.First,the optimal energy range of femtosecond laser modification is obtained through mechanism analysis.Second,the optimal parameters for a straight line and arc pattern are determined by optimizing the average output power,processing speed,and processing spacing.The results demonstrate why edge breakage in rounded corners is easy under different parameters.Finally,according to these conclusions,the processing is performed on a micro fused silica shell resonator with a Q factor exceeding 6 million.In addition,subsurface damage is rare throughout the fabrication process,and the surface roughness of the released cross section reaches the nanometer level.The improved Q factor helps suppress mechanical thermal noise and reduce zero bias and zero bias drift,constituting the primary method for enhancing the performance of the resonant gyroscope.
