Time-domain envelope-based quartz hemispherical resonator vibration parameter testing method and device

Abstract

The application relates to the technical field of high-precision sensors, and particularly relates to a quartz hemispherical resonator vibration parameter testing method and device based on a time domain envelope, which comprises the following steps: applying excitation to a quartz hemispherical resonator; determining a working modal frequency, a frequency split and an excitation signal based on a lip edge response signal; collecting vibration speed time domain signals of each scanning point; processing the vibration speed time domain signals of each scanning point based on the working modal frequency, and obtaining wave peak and wave valley information of each scanning point; performing linear fitting based on the wave peak information of each scanning point, and obtaining an attenuation time constant of each scanning point; obtaining a stiffness axis clamping angle of each scanning point through a mapping relationship based on the wave valley information and the attenuation time constant of each scanning point; and obtaining actual angle positions of a stiffness axis and a damping axis based on a circumferential mechanical angle, the attenuation time constant and the stiffness axis clamping angle of each scanning point; and the application can improve the efficiency and reliability of vibration parameter testing.

Description

Technical Field

[0001] This invention relates to the field of high-precision sensor technology, specifically to a method and apparatus for testing the vibration parameters of a quartz hemispherical harmonic oscillator based on time-domain envelope. Background Technology

[0002] As the core of high-precision inertial devices, the performance of a hemispherical resonator gyroscope (HRG) depends on the symmetry and energy loss characteristics of its resonator. The damping uniformity and frequency fragmentation of the resonator are two key parameters determining the gyroscope's accuracy and stability. In high-precision hemispherical resonator gyroscopes, there is an urgent need for an independent testing method that can quickly and accurately obtain complete vibration parameters such as damping non-uniformity and frequency fragmentation of the quartz resonator before it is coated and installed in the meter.

[0003] For quartz hemispherical harmonic oscillators, existing techniques typically treat frequency splitting and damping inhomogeneity as two independent measurement targets, employing different signal processing methods. Frequency splitting is primarily measured in the frequency domain, using spectral analysis to identify frequency intervals or the degree of splitting between different vibration modes, and obtaining the frequency axis angle through peak comparison. Damping inhomogeneity assessment, on the other hand, relies on time-domain methods, focusing on handling the vibration decay process. A typical approach involves applying excitation to multiple measurement points along the circumferential edge of the harmonic oscillator and recording the free decay signal, then fitting the local Q-value at each point. Finally, the Q-values ​​at each measurement point are summarized and compared to determine the locations of maximum and minimum damping, thereby calculating the damping inhomogeneity.

[0004] Existing methods suffer from drawbacks such as complex and time-consuming measurement processes, incomplete parameter detection, and insufficient signal processing accuracy and stability. There is an urgent need for a method that can quickly, accurately, and completely test these key vibration parameters. Summary of the Invention

[0005] In view of the above problems, the present invention provides a method for testing the vibration parameters of a quartz hemispherical harmonic oscillator based on time-domain envelope, which solves the technical problems of complex steps, extremely long time consumption, unreliable results and incomplete parameter acquisition in the prior art.

[0006] On the one hand, the present invention provides a method for testing the vibration parameters of a quartz hemispherical harmonic oscillator based on time-domain envelope, comprising the following steps: Step S1: Set up a vacuum test environment for the quartz hemispherical harmonic oscillator; Step S2: Apply excitation to the quartz hemispherical harmonic oscillator using a test signal; collect the lip response signal of the quartz hemispherical harmonic oscillator, and determine the working mode frequency, frequency split, and excitation signal based on the lip response signal; The excitation signal is used to excite the quartz hemispherical harmonic oscillator; multiple scanning points are determined, and the vibration velocity time-domain signal of each scanning point is collected; Step S3: Process the vibration velocity time-domain signal of each scanning point based on the working modal frequency to obtain the peak and trough information of each scanning point; Step S4: Perform linear fitting based on the peak information of each scanning point to obtain the attenuation time constant of each scanning point; Step S5: Based on the trough information and attenuation time constant of each scanning point, obtain the stiffness axis angle of each scanning point through the mapping relationship; Step S6: Based on the circumferential mechanical angle, decay time constant and stiffness axis included angle of each scanning point, perform stiffness axis positioning and damping parameter fitting to obtain damping non-uniformity parameters and the actual angular positions of stiffness axis and damping axis. Finally, the vibration parameters are obtained, including: frequency splitting, decay time constant of each scanning point, stiffness axis angle of each scanning point, damping non-uniformity parameters, and actual angular positions of the stiffness axis and damping axis.

[0007] Preferably, step S1 specifically includes: The pressure in the vacuum chamber containing the quartz hemispherical harmonic oscillator was pre-evacuated from atmospheric pressure to a low vacuum of 1 Pa; then the molecular pump was started to reduce the pressure in the vacuum chamber to below 0.001 Pa.

[0008] Preferably, in step S2, the test signal is a chirped signal containing the working mode frequency component or a swept frequency signal within a preset frequency range; The steps for determining the working mode frequency, frequency splitting, and excitation signal based on the lip response signal specifically include: The acquired lip response signal is subjected to a Fast Fourier Transform (FFT) to convert it into a frequency domain signal, and the operating mode frequency is obtained from the frequency domain signal. and ; The frequency split is determined based on the operating mode frequency, and the expression is:

[0009] in, For frequency splitting, This indicates the calculation of absolute value; An excitation signal is generated based on the operating mode frequency; the excitation signal has a frequency of A single-frequency sine wave.

[0010] Preferably, in step S2, the step of determining multiple scanning points and acquiring the vibration velocity time-domain signal of each scanning point specifically includes: N scanning points are set at circumferential positions along the edge of the harmonic oscillator, and the circumferential mechanical angle corresponding to scanning point i is determined. ; The vibration velocity time-domain signal of each scanning point is acquired sequentially at a preset sampling frequency. satisfy ,in, This indicates that the maximum value is calculated.

[0011] Preferably, step S3 specifically includes: The vibration velocity time-domain signal at each scanning point is subjected to bandpass filtering. The passband range of the bandpass filter is: ; Perform a Hilbert transform on the filtered time-domain signal to obtain an analytic signal, and take the magnitude of the analytic signal to obtain the signal envelope; For the signal envelope, local maxima are searched within a preset sliding window as peaks, and local minima are searched as troughs, ultimately yielding a peak data sequence. and trough data sequence , and The first The first peak and the second The amplitude of each trough, and They are respectively and The corresponding time.

[0012] Preferably, step S4 specifically includes, for each scan point: calculate The natural logarithm yields the logarithmic magnitude sequence. For peak data sequences ,by Using the logarithmic magnitude sequence as the independent variable and least-squares linear fitting as the dependent variable, the slope of the fitted line is obtained. ; pass The decay time constant was calculated. ; This yields the attenuation time constant for each scan point, where the attenuation time constant for the i-th scan point is... .

[0013] Preferably, step S5 specifically includes: Based on the decay time constant of scan point i For the amplitude of the trough Attenuation compensation is performed to obtain the corrected trough amplitude; The amplitude ratio of scan point i is calculated based on the ratio of the corrected trough amplitude to the original peak amplitude. ; Based on the amplitude ratio of scan point i Find the closest R value in the mapping table, and obtain the stiffness axis angle of the scanning point i by interpolation. .

[0014] Preferably, in step S6, the step of performing stiffness axis positioning and damping parameter fitting based on the circumferential mechanical angle, decay time constant, and stiffness axis included angle at each scanning point to obtain the actual angular positions of the stiffness axis and damping axis specifically includes: The actual angular positions of the four stiffness axes are determined based on the angular positions of each measurement point and the angle between the measurement point and the nearest stiffness axis. ; Using a trigonometric function that matches the 90° period and the average decay time constant of the circumferential harmonic oscillator. Damping non-uniform parameters Actual angular position relative to the damping axis ; The fitting expression is:

[0015] in, This represents the angular distribution of the decay time constant along the lip of the harmonic oscillator. express , This represents the damping non-uniformity parameter. This represents the fitted parameters.

[0016] On the one hand, the present invention provides a test device for the vibration parameters of a quartz hemispherical harmonic oscillator based on time-domain envelope, comprising: a test device, a signal acquisition device, and a data processing device; The testing device includes a vacuum chamber, a quartz hemispherical harmonic oscillator, a vacuum extraction device, and an excitation device. A quartz hemispherical resonator is installed inside the vacuum chamber. A vacuum extraction device is used to extract the vacuum from the vacuum chamber. An excitation device is electrically connected to the quartz hemispherical resonator and is used to excite the quartz hemispherical resonator. The signal acquisition device is communicatively connected to the excitation device and is used to acquire the vibration information of the quartz hemispherical harmonic oscillator; The data processing device is communicatively connected to the excitation device and the signal acquisition device, respectively. The data processing device performs a vibration parameter testing method based on the vibration information of the quartz hemispherical harmonic oscillator to obtain the vibration parameters.

[0017] Compared with the prior art, the present invention has at least the following beneficial effects: (1) This invention uses rapid modal identification and frequency sweeping combined with a scanning laser vibrometer in a vacuum environment for measurement. Only a small amount of attenuation peak and trough data needs to be obtained at a few measurement points to complete the identification of key parameters of the hemispherical harmonic oscillator. Compared with the traditional method that requires long-term sampling and multiple rounds of testing, this significantly shortens the testing cycle and improves the measurement efficiency. At the same time, this scheme has lower requirements for sampling data, and the measurement process is simpler and more efficient, making it suitable for rapid engineering testing and batch inspection scenarios.

[0018] (2) By optimizing the time-domain excitation and signal acquisition strategy, this invention can simultaneously obtain the attenuation response of multiple measurement points in a single experiment. Combined with the time-domain envelope peak and trough extraction fitting algorithm, it achieves integrated calculation of key characteristic parameters such as frequency fragmentation and damping characteristics. This method avoids the problems of step-by-step parameter measurement, fragmented results, and difficulty in cross-verification in traditional techniques, enabling the main characteristic parameters of the hemispherical harmonic oscillator to be obtained completely and uniformly, thereby improving the comprehensiveness and practicality of the identification results.

[0019] (3) This invention is based on linear fitting of the peak and valley points of the attenuated signal, without relying on a complex nonlinear optimization process. Therefore, it effectively overcomes the problems of traditional nonlinear fitting methods being easily affected by initial values ​​and noise and having insufficient stability. The algorithm has clear peak and valley features, a simple fitting process, strong anti-interference ability and result consistency, and can significantly improve the reliability and repeatability of feature parameter extraction, providing stable and reliable technical support for the accurate identification of hemispherical harmonic oscillators. Attached Figure Description

[0020] The accompanying drawings are for illustrative purposes only and are not intended to limit the scope of the invention.

[0021] Figure 1 The flowchart shows the method for testing the vibration parameters of a quartz hemispherical harmonic oscillator based on time-domain envelope provided by the present invention.

[0022] Figure 2 A block diagram of the quartz hemispherical harmonic oscillator vibration parameter testing device based on time-domain envelope provided by the present invention.

[0023] Figure 3 Detailed flowchart of the time-domain envelope-based method for testing the vibration parameters of a quartz hemispherical harmonic oscillator provided by this invention. Figure 4 The temporal envelope data image of the test fitting provided by the present invention and the schematic diagram of the corresponding positions of the peaks and valleys are shown. Detailed Implementation

[0024] To better understand the above-described objectives, features, and advantages of the present invention, the invention will be further described in detail below with reference to the accompanying drawings and specific embodiments. It should be noted that, unless otherwise specified, the embodiments of the present invention and the features thereof can be combined with each other. Furthermore, the present invention can be implemented in other ways different from those described herein; therefore, the scope of protection of the present invention is not limited to the specific embodiments disclosed below.

[0025] To illustrate the effectiveness of the method proposed in this invention, the following detailed description of the above technical solution is provided through a specific embodiment, such as... Figure 2 As shown, the present invention discloses a test device for the vibration parameters of a quartz hemispherical harmonic oscillator based on time-domain envelope, comprising: a test device, a signal acquisition device, and a data processing device; The testing device includes a vacuum chamber, a quartz hemispherical harmonic oscillator, a vacuum extraction device, and an excitation device. A quartz hemispherical resonator is installed inside the vacuum chamber. A vacuum extraction device is used to extract the vacuum from the vacuum chamber. An excitation device is electrically connected to the quartz hemispherical resonator and is used to excite the quartz hemispherical resonator. The signal acquisition device is communicatively connected to the excitation device and is used to acquire the vibration information of the quartz hemispherical harmonic oscillator; The data processing device is communicatively connected to the excitation device and the signal acquisition device, respectively. The data processing device processes the data based on the vibration information of the quartz hemispherical harmonic oscillator to obtain vibration parameters.

[0026] In some embodiments, the excitation device of the present invention may include a vibration excitation source and a PZT oscillator. The vibration excitation source generates an electrical signal of a specific frequency, such as a chirp signal or a sweep signal, which is transmitted to the PZT oscillator located inside the vacuum cavity on a clamping device for clamping a quartz hemispherical resonator. The PZT oscillator converts the electrical signal into mechanical vibration, thereby driving the quartz hemispherical resonator to oscillate.

[0027] In some embodiments, the signal acquisition device of the present invention may include a laser vibration meter controller and a scanning laser vibration meter; the laser vibration meter controller is communicatively connected to the vibration excitation source and the data processing device, respectively, and the data processing device sends control information to the laser vibration meter controller, and the laser vibration meter controller controls the movement sequence and angle of the laser emitted by the scanning laser vibration meter according to the control information.

[0028] A scanning laser vibrometer emits a laser beam through a glass window in a vacuum cavity, illuminating the lip of a quartz hemispherical harmonic oscillator. Based on the Doppler vibration measurement principle, the time-domain velocity of the lip of the harmonic oscillator is accurately measured as the vibration information.

[0029] The data processing device can issue commands, such as sending commands to control the "vacuum extraction system" to prepare the environment, commanding the "vibration excitation source" to output a specific frequency signal, and commanding the "laser vibrometer controller" to perform multi-point scanning.

[0030] The data processing device can also receive and process data, such as receiving multi-point vibration information collected from a scanning laser vibrometer, and then executing the time-domain envelope-based quartz hemispherical harmonic oscillator vibration parameter testing method provided by the present invention to obtain vibration parameters.

[0031] In some embodiments, the data processing apparatus of the present invention may be a computer.

[0032] like Figure 1 , Figure 3 As shown, this invention discloses a method for testing the vibration parameters of a quartz hemispherical harmonic oscillator based on time-domain envelope. The specific implementation steps are as follows: Step S1: Set up a vacuum test environment for the quartz hemispherical harmonic oscillator; In this step, the data processing device first sends a control command to the testing device to activate the vacuum extraction system. The mechanical pump within the vacuum extraction system starts working first, pre-evacuating the vacuum chamber from atmospheric pressure to a low vacuum of approximately 1 Pa. After the mechanical pump completes the initial evacuation, the data processing device sends a command to activate the molecular pump for further evacuation of the vacuum chamber. During the evacuation process, the vacuum gauge continuously monitors the pressure changes within the chamber and feeds the pressure data back to the data processing device in real time. The data processing device monitors and judges the pressure data; when the pressure within the chamber reaches and stabilizes below the preset threshold of 0.001 Pa, the system determines that the testing environment is ready.

[0033] This invention eliminates the influence of air damping on the vibration of a harmonic oscillator by setting up a vacuum testing environment. Setting the vacuum level below 0.001 Pa effectively reduces the energy dissipation of the harmonic oscillator due to air molecules, allowing the intrinsic damping characteristics of the harmonic oscillator to be fully realized. This provides the necessary testing conditions for accurately measuring key parameters such as damping non-uniformity.

[0034] Step S2: Apply excitation to the quartz hemispherical harmonic oscillator using a test signal; collect the lip response signal of the quartz hemispherical harmonic oscillator, and determine the working mode frequency, frequency split, and excitation signal based on the lip response signal; The excitation signal is used to excite the quartz hemispherical harmonic oscillator; multiple scanning points are determined, and the vibration velocity time-domain signal of each scanning point is collected; In this step, the present invention includes modal identification, frequency determination, and multi-point scanning data acquisition and processing, which are described in detail below.

[0035] (1) Determine the working mode frequency, frequency splitting and excitation signal In this step, the data processing device first sends a control command to the excitation device, which then applies a test signal to the quartz hemispherical resonator according to the command, causing the resonator to start oscillating.

[0036] The test signal can be a chirped signal containing the frequency components of the operating mode or a swept signal within a preset frequency range. The frequency of the chirped signal changes linearly with time, which can quickly excite the resonator's response in a wide frequency band; the swept signal scans the frequency response characteristics of the resonator by gradually changing the excitation frequency.

[0037] While the test signal is applied, the data processing device controls the signal acquisition device to continuously measure a fixed measurement point on the lip of the quartz hemispherical harmonic oscillator to obtain the vibration velocity response signal of the measurement point.

[0038] The data processing unit performs frequency domain analysis on the acquired lip response signal. Specifically, it performs a Fast Fourier Transform (FFT) on the time-domain response signal to convert the time-domain signal into a frequency-domain signal, thereby identifying the operating mode frequencies of the resonator in the spectrum. and Due to manufacturing defects in the quartz hemispherical harmonic oscillator, resulting in asymmetry, its operating modes exhibit frequency splitting. This means that the originally degenerate pair of orthogonal modes splits into two modes with slightly different frequencies, corresponding to frequencies of... and .

[0039] This invention determines frequency splitting based on the operating mode frequency, expressed as:

[0040] in, For frequency splitting, and For the operating modal frequency, This indicates the calculation of absolute value.

[0041] Then, an excitation signal is generated based on the operating mode frequency, wherein the excitation signal has a frequency of A single-frequency sine wave.

[0042] The excitation signal is applied to the quartz hemispherical harmonic oscillator, causing it to reach a stable vibration state at that frequency, thus preparing it for subsequent multi-point scanning measurements. The advantage of using the average frequency as the excitation frequency is that it can simultaneously excite two broken modes, causing the vibration envelope of the harmonic oscillator to exhibit modulation characteristics formed by the beat frequencies of the two frequency components.

[0043] (2) Acquire the vibration velocity time-domain signal at each scanning point. After the harmonic oscillator reaches a stable vibration state, the data processing device controls the scanning laser vibrometer to perform measurements according to the preset scanning scheme.

[0044] First, N scanning points are pre-defined at the circumferential position of the resonator lip. These scanning points are evenly or non-uniformly distributed on the circumference, and each scanning point corresponds to a circumferential mechanical angle. ,in . This represents the total number of scan points.

[0045] In a preferred embodiment, N is set to 8, corresponding to circumferential angles of 0°, 45°, 90°, 135°, 180°, 225°, 270°, and 315°, respectively, meaning a measurement point is set every 45°. This setting scheme takes into account the periodic characteristics of the four-antinode mode and can effectively capture the non-uniform distribution of damping and stiffness.

[0046] The data processing device controls the laser vibrometer to move the measurement spot to the position of each scanning point in a preset scanning point sequence. For each scanning point... After the laser spot is stabilized, the laser vibrometer uses the Doppler vibration measurement principle to collect data at a preset sampling frequency. The vibration velocity time-domain signal.

[0047] In some embodiments, the preset sampling frequency The following conditions must be met:

[0048] in, This indicates the maximum value to be calculated. Based on the above conditions, this invention employs a sampling rate of 10, which ensures high fidelity in signal acquisition and provides a reliable data foundation for subsequent accurate analysis.

[0049] The acquisition time T for each scan point is required to record at least one cycle of the attenuation waveform.

[0050] After completing the data acquisition of all N scanning points, this invention obtained the time-domain signal data of vibration velocity at multiple positions along the circumferential direction of the harmonic oscillator lip, laying a data foundation for subsequent time-domain envelope analysis and parameter extraction.

[0051] Step S3: Process the vibration velocity time-domain signal of each scanning point based on the working modal frequency to obtain the peak and trough information of each scanning point; In this step, the present invention performs filtering and envelope extraction on the vibration velocity time-domain signals acquired at each scanning point to obtain the peak and trough information of the envelope signal. This step includes bandpass filtering, Hilbert transform envelope extraction, and peak and trough detection processing, which are described in detail below.

[0052] (1) Bandpass filtering and envelope data extraction Due to noise interference in the actual measurement environment, the original vibration velocity time-domain signal contains not only the operating mode frequency but also other frequencies. and In addition to the useful components, it also contains low-frequency drift, high-frequency noise, and other unrelated frequency components. To improve signal quality, this invention uses a data processing device to perform bandpass filtering on the vibration velocity time-domain signal of each scanning point. The passband range of the bandpass filter is set to... That is, the passband is formed by the two splitting frequencies.

[0053] In some embodiments, the bandpass filter can be a classic IIR filter such as a Butterworth filter, Chebyshev filter, or elliptic filter, or it can be implemented using a frequency domain filtering method based on FFT. After bandpass filtering, the operating mode frequency components of the signal are preserved, while noise and interference components are effectively suppressed.

[0054] For the filtered time-domain signal, the data processing device performs a Hilbert transform on it to obtain an analytic signal. The magnitude of the analytic signal is then taken to obtain the signal envelope. The expression for the peak and trough values ​​contained in the signal envelope is as follows:

[0055]

[0056] in, and They represent in and The peak and trough values ​​corresponding to each moment. Indicates the initial amplitude. Represents the decay time constant. The angular frequencies of the two split sinusoidal components are... The angle between the current scanning point and the nearest stiffness axis when the resonator is operating in four amplitude modes.

[0057] (2) Extract the peak and trough data of the signal envelope. The data processing device extracts the signal envelope. A sliding window extremum detection algorithm is used to identify and extract all peak and trough locations and their corresponding amplitudes within the signal envelope. Specifically, a time window is defined, and local maxima are searched within the sliding window as peaks, and local minima are searched as troughs.

[0058] Through the above processing, the data processing device extracts two sets of data sequences for each scan point i: peak data sequence. and trough data sequence ,in The peak number is used to indicate the peak sequence. The number of peaks detected; The trough number, The number of troughs detected. and The first The first peak and the second The amplitude of each trough, and They are respectively and The corresponding time. (Refer to...) Figure 2 As shown in the figure, the time-domain envelope data image and the corresponding locations of the peaks and troughs are clearly displayed. The peak and trough data contain complete information on the decay time constant and the angle between the stiffness axes, providing a reliable data foundation for subsequent parameter extraction.

[0059] Figure 4 It displays the temporal envelope data image and the corresponding locations of peaks and troughs.

[0060] In some embodiments, to improve the accuracy and noise immunity of peak and trough detection, the envelope signal can be smoothed before extreme value detection. The data processing device uses a moving average method to smooth and filter the envelope signal, eliminating high-frequency noise interference.

[0061] Step S4: Perform linear fitting based on the peak information of each scanning point to obtain the attenuation time constant of each scanning point; This step utilizes the extracted peak data to calculate the attenuation time constant at each scanning point using a linear fitting method. This step transforms the exponential decay problem into a linear regression problem, thereby avoiding the problems of poor convergence, sensitivity to initial values, and long computation time that exist in traditional nonlinear fitting methods. This significantly improves the stability and computational efficiency of the algorithm, as described in detail below.

[0062] Obtain the peak data sequence obtained in the aforementioned steps. .

[0063] Perform a logarithmic transformation on the peak amplitude, and for each peak amplitude... Calculate its natural logarithm to obtain the logarithmic magnitude sequence, expressed as:

[0064] in, Indicates the first The logarithmic amplitude of each peak.

[0065] In time As the independent variable, Using the variable as the dependent variable, perform least-squares linear fitting to obtain the fitted line. ,in, The dependent variable is the one used to fit the straight line. The independent variable is used to fit the straight line. These represent the slope and bias of the fitted line, respectively.

[0066] According to the envelope theory model It can be seen that, Therefore, the slope of the fitted line That is Therefore, the decay time constant at this point can be calculated:

[0067] in This represents the decay time constant.

[0068] The data processing device repeats the above processing procedure for all N scan points to obtain the attenuation time constant for each scan point. The attenuation time constant for the i-th scan point is... .

[0069] Step S5: Based on the trough information and attenuation time constant of each scanning point, obtain the stiffness axis angle of each scanning point through the mapping relationship; In this step, using the extracted trough data and attenuation time constant, the angle between each scanning point and the nearest stiffness axis is calculated through attenuation compensation and ratio mapping methods. Since the troughs of the envelope signal are modulated by the position of the measurement point relative to the stiffness axis, the angle information can be inferred by analyzing the amplitude ratio between the peaks and troughs, as described in detail below.

[0070] For each scan point i, the data processing device extracts the step trough amplitude sequence { } and its corresponding time series { According to the theoretical model of the envelope signal, the amplitude of the trough is also subject to an exponential decay term. Modulation.

[0071] Since the amplitude of the wave troughs is affected by attenuation to varying degrees at different times, in order to extract the modulation information caused solely by the stiffness axis angle, it is necessary to first eliminate the attenuation effect. The data processing device utilizes the attenuation time constant of scan point i. Attenuation compensation is applied to each trough amplitude, and the corrected trough amplitude is calculated. The expression is:

[0072] For each scan point i, the amplitude ratio of scan point i is calculated based on the corrected trough amplitude and the original peak amplitude. The expression is:

[0073] in, This represents the original peak amplitude.

[0074] Based on the theoretical model of the four-antinode mode, the amplitude ratio can be derived. Angle with stiffness axis There is a definite functional relationship between them.

[0075] Correspondingly, the data processing device of the present invention pre-stores a high-resolution [database / ... Mapping table. This mapping table is generated offline through theoretical formula calculations and covers... The range is from 0° to 22.5°. The mapping table stores the corresponding values ​​indexed by R. Angle value. In actual calculations, the data processing device uses the calculated amplitude ratio of scan point i. The closest R value is found in the mapping table, and the stiffness axis angle of the scanning point i is obtained by interpolation. .

[0076] The data processing device obtains the angle between each scanning point and the nearest stiffness axis. This angular information reflects the positional relationship of the measurement point relative to the principal axis of the harmonic oscillator's stiffness distribution, and is key data for locating the angular position of the stiffness axis.

[0077] Step S6: Based on the circumferential mechanical angle, decay time constant and stiffness axis included angle of each scanning point, perform stiffness axis positioning and damping parameter fitting to obtain the actual angular positions of stiffness axis and damping axis. Finally, the vibration parameters are obtained, including: frequency splitting, decay time constant of each scanning point, stiffness axis angle of each scanning point, and actual angular positions of the stiffness axis and damping axis.

[0078] In this step, the circumferential mechanical angle of each scanning point is utilized. decay time constant and the included angle of the stiffness axis Through stiffness axis positioning and damping parameter fitting algorithms, the complete characteristic parameters of the harmonic oscillator, such as the angular position of the stiffness axis, the angular position of the damping axis, and the actual angular positions of the stiffness axis and the damping axis, are finally obtained, as detailed below.

[0079] (1) Establish the scanning point angle mapping relationship The data processing device will process the known circumferential mechanical angles of each scanning point. Angle with stiffness axis Link them to form a dataset .in The absolute position angle of the scanning point along the circumferential direction of the harmonic oscillator lip is a pre-defined known quantity; Let be the angle between this point and the nearest stiffness axis.

[0080] (2) Precise positioning of stiffness axis angle In the four-antinode mode, the harmonic oscillator theoretically has four stiffness axes and four damping axes, which are staggered at 90° intervals in the circumferential direction. The stiffness axes correspond to the directions where the stiffness of the harmonic oscillator is greatest, and the damping axes correspond to the directions where the damping is greatest. The angle between the measurement point and the nearest stiffness axis ranges from 0° to 22.5°. By comparing the corner positions of each measurement point By combining the obtained angle with the nearest stiffness axis, the actual angular positions of the four stiffness axes can be accurately determined. .

[0081] (3) Fitting of damping non-uniform parameters According to the theory of the four-antinode mode, the damping distribution in the circumferential direction also exhibits fourfold symmetry, showing a periodic variation with a period of 90°. Therefore, the data processing device uses a periodic function with a period of 90° to fit the circumferential distribution of the decay time constant. Specifically, since the damping characteristics in the four-antinode mode exhibit four repetitions on the circumference, a trigonometric function matching the 90° period can be used to fit the damping response to reflect the increasing or decreasing trend of damping at different angles. The fitting expression is:

[0082] in, This represents the angular distribution of the decay time constant along the lip of the harmonic oscillator. The average decay constant in the circumferential direction of the harmonic oscillator. This represents the damping non-uniformity parameter. This represents the fitted parameters.

[0083] During the fitting process, The larger the amplitude of the parameter used to characterize damping inhomogeneity, the more significant the difference in damping distribution. This is achieved by fitting the parameters... angular position relative to the original measurement point By comparing these values, we can further obtain the actual angular positions of the four damping axes that maximize and minimize damping, denoted as: .

[0084] After completing all the above calculations, the data processing device summarizes and generates the complete vibration parameters of the harmonic oscillator, including... (1) Frequency decomposition The value is obtained from the spectral analysis in step S2, which characterizes the degree of asymmetry in the stiffness of the harmonic oscillator.

[0085] (2) Operating mode frequency and The frequency values ​​of the two split modes are the reference frequencies for the operation of the gyroscope.

[0086] (3) Attenuation time constant at each scanning point The result reflects the local damping characteristics of each measurement point and is obtained by linear fitting in step S4.

[0087] (4) Angle of stiffness axis at each scanning point This reflects the positional relationship of each measurement point relative to the stiffness axis, and is obtained by mapping the ratio in step S5.

[0088] (5) Actual angular position of the stiffness axis Damping non-uniformity parameters and the actual angular position of the damping axis It reflects the absolute position of the four stiffness axes and four damping axes in the circumferential direction, as well as the degree of damping non-uniformity.

[0089] These parameters comprehensively and completely describe the vibration characteristics of the quartz hemispherical harmonic oscillator, providing complete data support for evaluating the oscillator's quality, optimizing gyroscope performance, and implementing error compensation.

[0090] The method of this invention can quickly, accurately, and completely obtain all the key vibration parameters of the harmonic oscillator through a single test, a small number of measurement points, and a short measurement time, significantly improving measurement efficiency and accuracy; it has broad application prospects in precision instrument fields such as high-precision inertial sensor manufacturing and hemispherical resonator gyroscope performance evaluation.

[0091] While the specific embodiments of the present invention depict actions or steps in a particular order, this should be understood as requiring such actions or steps to be performed in the specific order shown or in sequential order, or requiring all illustrated actions or steps to be performed to achieve the desired result. In certain environments, multitasking and parallel processing may be advantageous. Similarly, although several specific implementation details are included in the above discussion, these should not be construed as limiting the scope of this disclosure. Certain features described in the context of individual embodiments may also be implemented in combination in a single implementation. Conversely, various features described in the context of a single implementation may also be implemented individually or in any suitable sub-combination in multiple implementations.

[0092] The above description is only a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any changes or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in the present invention should be included within the scope of protection of the present invention.

Claims

1. A method for testing the vibration parameters of a quartz hemispherical harmonic oscillator based on time-domain envelope, characterized in that, Includes the following steps: Step S1: Set up a vacuum test environment for the quartz hemispherical harmonic oscillator; Step S2: Apply excitation to the quartz hemispherical harmonic oscillator using a test signal; collect the lip response signal of the quartz hemispherical harmonic oscillator, and determine the working mode frequency, frequency split, and excitation signal based on the lip response signal; The excitation signal is used to excite the quartz hemispherical harmonic oscillator; multiple scanning points are determined, and the vibration velocity time-domain signal of each scanning point is collected; Step S3: Process the vibration velocity time-domain signal of each scanning point based on the working modal frequency to obtain the peak and trough information of each scanning point; Step S4: Perform linear fitting based on the peak information of each scanning point to obtain the attenuation time constant of each scanning point; Step S5: Based on the trough information and attenuation time constant of each scanning point, obtain the stiffness axis angle of each scanning point through the mapping relationship; Step S6: Based on the circumferential mechanical angle, decay time constant and stiffness axis included angle of each scanning point, perform stiffness axis positioning and damping parameter fitting to obtain damping non-uniformity parameters and the actual angular positions of stiffness axis and damping axis. Finally, the vibration parameters are obtained, including: frequency splitting, decay time constant of each scanning point, stiffness axis angle of each scanning point, damping non-uniformity parameters, and actual angular positions of the stiffness axis and damping axis.

2. The method for testing the vibration parameters of a quartz hemispherical harmonic oscillator based on time-domain envelope as described in claim 1, characterized in that, Step S1 specifically includes: The pressure in the vacuum chamber containing the quartz hemispherical harmonic oscillator was pre-evacuated from atmospheric pressure to a low vacuum of 1 Pa; then the molecular pump was started to reduce the pressure in the vacuum chamber to below 0.001 Pa.

3. The method for testing the vibration parameters of a quartz hemispherical harmonic oscillator based on time-domain envelope according to claim 2, characterized in that, In step S2, the test signal is a chirped signal containing the working mode frequency component or a swept frequency signal within a preset frequency range; The steps for determining the working mode frequency, frequency splitting, and excitation signal based on the lip response signal specifically include: The acquired lip response signal is subjected to a Fast Fourier Transform (FFT) to convert it into a frequency domain signal, and the operating mode frequency is obtained from the frequency domain signal. and ; The frequency split is determined based on the operating mode frequency, and the expression is: in, For frequency splitting, This indicates the calculation of absolute value; An excitation signal is generated based on the operating mode frequency; the excitation signal has a frequency of A single-frequency sine wave.

4. The method for testing the vibration parameters of a quartz hemispherical harmonic oscillator based on time-domain envelope according to claim 3, characterized in that, In step S2, the step of determining multiple scanning points and acquiring the vibration velocity time-domain signal of each scanning point specifically includes: N scanning points are set at circumferential positions along the edge of the harmonic oscillator, and the circumferential mechanical angle corresponding to scanning point i is determined. ; The vibration velocity time-domain signal of each scanning point is acquired sequentially at a preset sampling frequency. satisfy ,in, This indicates that the maximum value is calculated.

5. The method for testing the vibration parameters of a quartz hemispherical harmonic oscillator based on time-domain envelope according to claim 4, characterized in that, Step S3 specifically includes: The vibration velocity time-domain signal at each scanning point is subjected to bandpass filtering. The passband range of the bandpass filter is: ; Perform a Hilbert transform on the filtered time-domain signal to obtain an analytic signal, and take the magnitude of the analytic signal to obtain the signal envelope; For the signal envelope, local maxima are searched within a preset sliding window as peaks, and local minima are searched as troughs, ultimately yielding a peak data sequence. and trough data sequence , and The first The first peak and the second The amplitude of each trough, and They are respectively and The corresponding time.

6. The method for testing the vibration parameters of a quartz hemispherical harmonic oscillator based on time-domain envelope according to claim 5, characterized in that, Step S4 specifically includes, for each scan point: calculate The natural logarithm yields the logarithmic magnitude sequence. For peak data sequences ,by Using the logarithmic magnitude sequence as the independent variable and least-squares linear fitting as the dependent variable, the slope of the fitted line is obtained. ; pass The decay time constant was calculated. ; This yields the attenuation time constant for each scan point, where the attenuation time constant for the i-th scan point is... .

7. The method for testing the vibration parameters of a quartz hemispherical harmonic oscillator based on time-domain envelope as described in claim 6, characterized in that, Step S5 specifically includes: Based on the decay time constant of scan point i For the amplitude of the trough Attenuation compensation is performed to obtain the corrected trough amplitude; The amplitude ratio of scan point i is calculated based on the ratio of the corrected trough amplitude to the original peak amplitude. ; Based on the amplitude ratio of scan point i Find the closest R value in the mapping table, and obtain the stiffness axis angle of the scanning point i by interpolation. .

8. The method for testing the vibration parameters of a quartz hemispherical harmonic oscillator based on time-domain envelope according to claim 7, characterized in that, In step S6, the step of performing stiffness axis positioning and damping parameter fitting based on the circumferential mechanical angle, decay time constant, and stiffness axis included angle at each scanning point to obtain the actual angular positions of the stiffness axis and damping axis specifically includes: The actual angular positions of the four stiffness axes are determined based on the angular positions of each measurement point and the angle between the measurement point and the nearest stiffness axis. ; The damping response is fitted using a trigonometric function matching the 90° period and the average decay time constant of the circumferential harmonic oscillator. Parameter identification is then performed on the fitted function to obtain the damping non-uniformity parameters. Actual angular position relative to the damping axis ; The fitting expression is: in, This represents the angular distribution of the decay time constant along the lip of the harmonic oscillator. This represents the average decay constant of the harmonic oscillator in the circumferential direction. This represents the damping non-uniformity parameter. This represents the fitted parameters.

9. A device for testing the vibration parameters of a quartz hemispherical harmonic oscillator based on time-domain envelope, characterized in that, include: Testing equipment, signal acquisition equipment, and data processing equipment; The testing device includes a vacuum chamber, a quartz hemispherical harmonic oscillator, a vacuum extraction device, and an excitation device. A quartz hemispherical resonator is installed inside the vacuum chamber. A vacuum extraction device is used to extract the vacuum from the vacuum chamber. An excitation device is electrically connected to the quartz hemispherical resonator and is used to excite the quartz hemispherical resonator. The signal acquisition device is communicatively connected to the excitation device and is used to acquire the vibration information of the quartz hemispherical harmonic oscillator; The data processing device is communicatively connected to the excitation device and the signal acquisition device, respectively. The data processing device performs a vibration parameter testing method based on the vibration information of the quartz hemispherical harmonic oscillator to obtain the vibration parameters.

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