A method for jointly compensating for time delay and damping asymmetric errors of a full angle hemispherical resonator gyro

Abstract

The application relates to a full-angle hemispherical gyro joint compensation method of time delay and damping asymmetric error, and belongs to the technical field of inertial navigation, which comprises the following steps: S1, acquiring a self-precession excitation signal and an angular velocity measurement value signal of gyro output; S2, preliminarily estimating the time delay of the gyro by adopting a maximum likelihood weighted cross-correlation time delay estimation method; S3, estimating the damping asymmetric error of the gyro by a recursive least square method by utilizing the estimated time delay; S4, re-estimating the time delay of the gyro by utilizing the estimated damping asymmetric error, obtaining updated estimated time delay, judging whether the updated estimated time delay converges or not, if the updated estimated time delay does not converge, returning to step S3, re-estimating the damping asymmetric error of the gyro by the recursive least square method by utilizing the updated estimated time delay, if the updated estimated time delay converges, obtaining final estimated time delay; and S5, compensating the final estimated time delay and the damping asymmetric error to a control system of the gyro. The application improves the measurement precision and long-term stability of the gyro.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of inertial navigation, and particularly relates to a joint compensation method for delay and damping asymmetry errors of a full-angle hemispherical gyro. BACKGROUND

[0002] The hemispherical resonator gyro (HRG) is a high-precision inertial sensor based on the Coriolis vibration principle, widely used in aerospace, marine navigation, land positioning, and space exploration. The HRG measures angular velocity by detecting the precession effect of the standing wave in the resonant cavity, with high precision, long service life, no wearing parts, strong environmental adaptability, and excellent reliability. The HRG has two main working modes: force balance mode and full-angle mode. Among them, the full-angle mode has direct angular rate output, wide dynamic range, and high stability of the proportional factor, becoming an important research direction in the field of HRG.

[0003] In the full-angle mode, the measurement accuracy of the HRG is significantly affected by the structural asymmetry of the resonator, especially the damping asymmetry and the delay. The damping asymmetry is caused by the uneven distribution of the resonator damping, leading to angle-dependent drift and affecting the long-term stability of the system. The delay is mainly caused by the lag effect in the signal sampling and data processing process, causing a time sequence deviation between the input angular velocity and the measured signal, further exacerbating the measurement error of the system. Although existing research has proposed various methods to compensate for damping asymmetry errors, these methods mostly do not consider the impact of delay, resulting in limited compensation effect. In the prior art, the invention patent with publication number CN112504258A proposes an adaptive circuit to control the quartz hemispherical resonator gyro in full-angle mode, the invention patent with publication number CN115031713A proposes a method for self-calibration of detection signal nonlinearity to identify and self-calibrate the angle calculation error caused by the detection signal nonlinearity of the full-angle mode hemispherical resonator gyro, and the invention patent with publication number CN113587954A provides a damping uneven compensation control method and system to solve the technical problem of drift error caused by damping unevenness in the full-angle mode hemispherical resonator gyro. However, these methods do not fully consider the impact of delay on system performance, especially in high-precision measurement, where delay can cause the parameter update of the adaptive algorithm to lag, further affecting the compensation effect of damping asymmetry errors.

[0004] Therefore, the existing HRG error compensation methods have obvious deficiencies in dealing with the joint impact of delay and damping asymmetry errors, and a method that can simultaneously compensate for delay and damping asymmetry errors is needed to improve the measurement accuracy and long-term stability of the HRG system. SUMMARY

[0005] In view of the deficiencies of the prior art, the purpose of the present application is to provide a full-angle hemispherical gyro delay and damping asymmetric error combined compensation method, which can improve the measurement accuracy and long-term stability of the hemispherical resonator gyro system.

[0006] To achieve the above-mentioned purpose, the present application adopts the following technical solution: a full-angle hemispherical gyro delay and damping asymmetric error combined compensation method, comprising the following steps:

[0007] S1, set a self-precession excitation signal to excite the hemispherical gyro to vibrate, and obtain the angular velocity measurement value signal of the self-precession excitation signal and the gyro output;

[0008] S2, preliminarily estimate the delay of the gyro by using a maximum likelihood weighted cross-correlation delay estimation method, and obtain the estimated delay;

[0009] S3, estimate the damping asymmetric error of the gyro by using the estimated delay through a recursive least squares method, and obtain the estimated damping asymmetric error;

[0010] S4, re-estimate the delay of the gyro by using the estimated damping asymmetric error, obtain the updated estimated delay, judge whether the updated estimated delay converges, if not, return to step S3, re-estimate the damping asymmetric error of the gyro by using the updated estimated delay through the recursive least squares method, if yes, obtain the final estimated delay;

[0011] S5, compensate the final estimated delay and the damping asymmetric error to the control system of the gyro.

[0012] Preferably, the specific method of step S1 is:

[0013] S11, express the control principle of the full-angle mode with an elliptical orbit, and introduce the measurement noise to obtain the gyro angular velocity of the hemispherical resonator gyro at a certain time;

[0014] S12, set the self-precession excitation signal without external inertial angular velocity input, so that the gyro is in a working state, and record the complete self-precession excitation signal and collect the complete angular velocity measurement value signal of the gyro output;

[0015] Cut off the angular velocity measurement value signal of the gyro output from time k to time k+t to obtain a first angular velocity measurement value signal with a time length of t;

[0016] Cut off the self-precession excitation signal from time k to time k+t to obtain a first self-precession excitation signal with a time length of t.

[0017] Preferably, the specific method of step S2 is:

[0018] S21, a maximum likelihood weighted cross-correlation delay estimation method is used to calculate a weighted cross-correlation function of the first angular velocity measurement signal and the first self-rotation excitation signal;

[0019] S22, an estimated delay is calculated: the weighted cross-correlation function of the first angular velocity measurement signal and the first self-rotation excitation signal is inverse fast Fourier transformed, and then a position of an inverse transformation maximum value is found, which corresponds to a horizontal coordinate time and is the estimated delay .

[0020] Preferably, the specific method of step S3 is:

[0021] S31, the estimated delay is used to intercept the self-rotation excitation signal from to obtain a second self-rotation excitation signal with a time length of t;

[0022] S32, the first angular velocity measurement signal and the second self-rotation excitation signal are used to solve an estimated damping asymmetric error by using a least square method.

[0023] Preferably, the specific method of step S32 is:

[0024] S321, an estimated parameter vector is initialized;

[0025] S322, for each time k, a regression vector is constructed at the estimated delay .

[0026] S323, based on the gyro angular velocity, the estimated parameter vector and the regression vector, an error between an actual measurement value and a predicted value of the gyro angular velocity at time k is calculated;

[0027] S324, based on the regression vector, a covariance matrix and the error between the actual measurement value and the predicted value of the gyro angular velocity at time k, the estimated parameter vector is re-estimated to obtain an updated estimated parameter vector at time k;

[0028] S325, the covariance matrix is updated.

[0029] Preferably, the specific method of step S4 is:

[0030] S41, the estimated damping asymmetric error is used to obtain a gyro angular velocity after compensation at a certain time;

[0031] S42, the gyro angular velocity after compensation at the certain time is used to update the angular velocity at each time in the first angular velocity measurement signal to obtain a second angular velocity measurement signal;

[0032] S43, using the maximum likelihood weighted cross-correlation delay estimation method, calculating the weighted cross-correlation function of the second angular velocity measurement signal and the second self-precession excitation signal;

[0033] S44, recalculating the estimated delay: performing inverse fast Fourier transform on the weighted cross-correlation function of the second angular velocity measurement signal and the second self-precession excitation signal, and then finding the position of the inverse transform maximum value, which corresponds to the horizontal coordinate time, as the updated estimated delay ;

[0034] S45, judging whether the updated estimated delay converges: setting a delay convergence threshold, judging whether the difference between the updated estimated delay and the last estimated delay is less than the delay convergence threshold; if not, returning to step S3, re-estimating the damping asymmetry error using the updated estimated delay ; if yes, the updated estimated delay and the damping asymmetry error are the final estimated results.

[0035] Compared with the prior art, the present application has the following beneficial effects: the present application firstly preliminarily estimates the delay of the system through the maximum likelihood weighted cross-correlation delay estimation, and dynamically compensates the damping asymmetry error by combining the recursive least square algorithm, realizing high-precision joint compensation of the delay and the damping asymmetry error. The present application significantly reduces the angle-dependent drift error through multiple iterations and optimization, and improves the measurement accuracy and long-term stability of the hemispherical resonator gyro. The results of the present application have high reliability, strong universality, simple operation, high precision after compensation of the full-angle hemispherical resonator gyro, good practicability, and are suitable for high-precision inertial navigation systems in the fields of aerospace, marine navigation, land positioning and space exploration. The present application solves the problem of insufficient consideration of the coupling effect of the delay and the damping asymmetry error in the prior art, resulting in insufficient compensation accuracy and poor system stability. BRIEF DESCRIPTION OF DRAWINGS

[0036] In order to more clearly illustrate the technical solutions of the present application or the prior art, the following will briefly introduce the drawings needed to be used in the embodiments or prior art description. Obviously, the drawings described below can also be obtained by those skilled in the art without creative labor on the basis of these drawings.

[0037] Figure 1 A flowchart of the joint compensation method of the delay and the damping asymmetry error of the full-angle hemispherical gyro is provided for the present application.

[0038] Figure 2 The mode angle and the change of the spin precession excitation signal of the gyro in the first embodiment of the present application are shown.

[0039] Figure 3 This describes the damping parameters estimated using the joint compensation method of the present invention in Embodiment 1 of the present invention, as well as the convergence process of the gain over time.

[0040] Figure 4 This diagram illustrates the angular drift deviation results of a full-angle hemispherical resonant gyroscope after uncompensated conditions, compensation using only damping asymmetry, and compensation using the method provided by this invention, as shown in Embodiment 1 of the present invention. Detailed Implementation

[0041] To make the objectives, technical solutions, and advantages of this invention clearer, the technical solutions of this invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of this invention. Based on the embodiments of this invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this invention. To make the above features and advantages of this invention more apparent and understandable, specific embodiments are provided below with reference to the accompanying drawings for detailed description.

[0042] like Figure 1 As shown, an embodiment of the present invention provides a method for joint compensation of delay and damping asymmetry error in a full-angle hemispherical gyroscope, comprising the following steps:

[0043] S1. Set the self-precession excitation signal to excite the hemispherical gyroscope to vibrate, and obtain the self-precession excitation signal and the angular velocity measurement value signal output by the gyroscope;

[0044] S2. The delay of the gyroscope is initially estimated using the maximum likelihood weighted cross-correlation delay estimation method to obtain the estimated delay;

[0045] S3. Using the estimated delay, estimate the damping asymmetry error of the gyroscope through the recursive least squares method to obtain the estimated damping asymmetry error.

[0046] S4. Using the estimated damping asymmetry error, re-estimate the gyroscope's delay to obtain the updated estimated delay; determine whether the updated estimated delay has converged; if it has not converged, return to step S3, and use the updated estimated delay to re-estimate the gyroscope's damping asymmetry error using the recursive least squares method; if it has converged, obtain the final estimated delay.

[0047] S5. The final estimated delay and damping asymmetry errors are compensated into the gyroscope's control system.

[0048] In this embodiment, the specific method of step S1 is as follows:

[0049] S11, the control principle of the full angle mode is expressed by an elliptical orbit, and measurement noise is introduced to obtain the gyro angular velocity of the hemispherical resonator gyro at a certain time is:

[0050] ;

[0051] wherein κ represents a gyro scale factor, Ω represents an external input angular rate, ω0 represents a resonance frequency, θ represents a mode angle of the gyro, Q represents a quality factor of the gyro, γ1 and γ2 represent two orthogonal components of a damping asymmetry error, a represents a long axis of the orbit, P(θ) represents a precession excitation signal at a certain time, and w represents introduced measurement noise;

[0052] S12, in the absence of external inertial angular velocity input, i.e. Ω is 0, the precession excitation signal is artificially set, the gyro is in a working state, and the complete precession excitation signal and the complete gyro output angular velocity measurement signal are recorded;

[0053] The gyro output angular velocity measurement signal from time k to time k+t is intercepted to obtain a first angular velocity measurement signal T a1 ;

[0054] The precession excitation signal from time k to time k+t is intercepted to obtain a first precession excitation signal T a2 .

[0055] In the embodiment, the specific method of step S2 is:

[0056] S21, the first angular velocity measurement signal T a1 is cross-correlated with the first precession excitation signal T a2 Due to the sluggishness of the system, there is a certain time delay relationship. Therefore, the maximum likelihood weighted cross-correlation time delay estimation method is used to calculate the weighted cross-correlation function G a1 of the first angular velocity measurement signal T a2 and the first precession excitation signal T a as follows:

[0057] ;

[0058] wherein ψ a (f) is the first maximum likelihood weighting function, G af represents the cross power spectrum of the first angular velocity measurement signal T a1 and the first precession excitation signal T a2 , j represents an imaginary number, f represents a sampling frequency, h represents a time delay in gyro signal transmission, and N is the number of discrete points in the signal;

[0059] ;

[0060] ;

[0061] ;

[0062] ;

[0063] ;

[0064] wherein T a1f and T a2f are the Fourier transform functions of the first angular velocity measurement signal T a1 and the first self-rotation excitation signal T a2 respectively, are functions of frequency; denotes the complex conjugate of T a1f , denotes the complex conjugate of T a2f ; G a1f is the auto-power spectral density of the first angular velocity measurement signal T a1 , obtained by multiplying T a1f by its complex conjugate; G a2f is the auto-power spectral density of the first self-rotation excitation signal T a2 , obtained by multiplying T a2f by its complex conjugate; C a denotes the coherence function of the first angular velocity measurement signal T a1 and the first self-rotation excitation signal T a2 ;

[0065] S22, calculate the estimated time delay: perform inverse fast Fourier transform on the weighted cross-correlation function G a1 of the first angular velocity measurement signal T a2 and the first self-rotation excitation signal T a , and then find the position of the maximum value of the inverse transform, which corresponds to the time delay :

[0066] ;

[0067] wherein IFFT| | denotes inverse fast Fourier transform.

[0068] In this embodiment, the specific method of step S3 is as follows:

[0069] S31, use the estimated time delay to intercept the self-rotation excitation signal from time t to time t , and obtain the second self-rotation excitation signal T b2 with a time length of t;

[0070] S32, aligning the second precession excitation signal T a1 and the first angular velocity measurement signal T b2 , solving two orthogonal components of the estimated damping asymmetry error by least square method and .

[0071] In this embodiment, the second precession excitation signal T b2 is actually a time series signal of the precession excitation signal P(θ), and the first angular velocity measurement signal T a1 is actually a time series signal of the gyro angular velocity , both of which satisfy the gyro angular velocity formula relationship in S11. Align the second precession excitation signal T b2 with the first angular velocity measurement signal T a1 ; the sample points in the first angular velocity measurement signal T a1 can be denoted as θ(0), θ(1),..., θ(N-1), corresponding to the time k, k+1,..., k+N-1; the sample points in the second precession excitation signal T b2 can be denoted as P(0), P(1),..., P(N-1), corresponding to the time , ,..., ;

[0072] Therefore, the specific method of step S32 is:

[0073] S321, initialize the estimated parameter vector :

[0074] ;

[0075] wherein, denotes the gain of the estimated precession excitation signal, and respectively denote two orthogonal components of the estimated damping asymmetry error, and T denotes the transpose of the matrix;

[0076] S322, for each time k, construct a regression vector Φ(k) as follows on the estimated delay :

[0077] ;

[0078] S323, based on the gyro angular velocity, the estimated parameter vector and the regression vector, calculate the error ε(k) between the actual measurement value and the predicted value of the gyro angular velocity at time k:

[0079] ;

[0080] wherein, is the actual measurement value of the gyro angular velocity at time k, is the predicted value of the gyro angular velocity at time k. Since the signal sampled is discrete, k-1 indicates the time point before the time k of the signal, represents the estimated parameter vector at time k-1;

[0081] S324, based on the regression vector, the covariance matrix and the error between the actual measurement value and the predicted value of the gyro angular velocity at time k, re-estimates the estimated parameter vector to obtain the updated estimated parameter vector at time k :

[0082] ;

[0083] wherein D(k-1) represents the covariance matrix at time k-1, which can be a larger positive diagonal matrix in the first use, and λ represents a forgetting factor;

[0084] and are the second term and the third term of the updated estimated parameter vector at time k respectively;

[0085] the damping angle θ γ is:

[0086] ;

[0087] wherein atan2() represents a four-quadrant inverse tangent function;

[0088] S325, update the covariance matrix:

[0089] ;

[0090] wherein D(k) represents the covariance matrix at time k.

[0091] In the embodiment, the specific method of step S4 is:

[0092] S41, using the estimated damping asymmetric error, the gyro angular velocity after compensation at a certain time is obtained:

[0093] ;

[0094] S42, using the formula of the gyro angular velocity after compensation at a certain time , the angular velocity of each time in the first angular velocity measurement signal T a1 is updated to obtain the second angular velocity measurement signal T b1 ;

[0095] S43, using a maximum likelihood weighted cross-correlation delay estimation method, calculate a second angular velocity measurement signal T b1 and a second self-rotation excitation signal T b2 , a weighted cross-correlation function G b is as follows:

[0096] ;

[0097] where ψ b (f) is a second maximum likelihood weighting function, G bf represents the cross-power spectrum of the second angular velocity measurement signal T b1 and the second self-rotation excitation signal T b2 , j represents an imaginary number, f represents a frequency, and h is a delay variable;

[0098] ;

[0099] ;

[0100] ;

[0101] ;

[0102] ;

[0103] where T b1f and T b2f are the Fourier transform functions of the second angular velocity measurement signal T b1 and the second self-rotation excitation signal T b2 , respectively, and are functions of frequency; represents the complex conjugate of T b1f , represents the complex conjugate of T b2f ; G b1f is the auto-power spectral density of the second angular velocity measurement signal T b1 , obtained by multiplying T b1f by its complex conjugate; G b2f is the auto-power spectral density of the second self-rotation excitation signal T b2 , obtained by multiplying T b2f by its complex conjugate; C b represents the coherence function of the second angular velocity measurement signal T b1 and the second self-rotation excitation signal T b2 ;

[0104] S44, recalculate the estimated delay: for the second angular velocity measurement signal T b1 and the second self-rotation excitation signal T b2The weighted cross-correlation function G b Perform an inverse fast Fourier transform, then find the location of the maximum value of the inverse transform. The time corresponding to this location on the x-axis is the estimated delay for updating. ;

[0105] S45. Determine the delay of the update estimate. Convergence status: Set a delay convergence threshold (threshold) to determine the estimated delay for updating. Delay compared to the last estimated Is the difference less than the delay convergence threshold? If not, return to step S3 and use the updated estimated delay. Re-estimate the damping asymmetry error; if so, update the estimated delay. Two orthogonal components of damping asymmetry error and This is the final estimated result.

[0106] Experimental Example: To verify the correctness of this invention, a combined compensation for delay and damping asymmetry errors was performed on a full-angle hemispherical resonator gyroscope according to the method provided in this invention. The quality factor of this full-angle hemispherical resonator gyroscope is approximately 10 million, and the frequency split is approximately 2.5 mHz.

[0107] Figure 2 The experiment shows the changes in the mode angle and spin-precession excitation signal of the gyroscope. Figure 3 The convergence process of the damping parameters and gain over time estimated using the joint compensation method of the present invention is shown. The final estimated damping parameters and delay results obtained using the method provided by the present invention are listed in Table 1.

[0108] Table 1. Damping parameters and delay results of a full-angle hemispherical resonant gyroscope obtained using the method of the present invention:

[0109]

[0110] The estimated gyroscope parameters were compensated into the gyroscope's control system. By changing the mode angle, the effects of damping asymmetry error and delay error on the angular drift deviation of the hemispherical resonator gyroscope were analyzed. (See [link to relevant documentation]). Figure 4, the radial coordinate unit is an elliptical orbit parameter, that is, the short axis b of the harmonic oscillator elliptical motion trajectory divided by the long axis a. In the case of not compensating for the damping asymmetry error and the delay error, the maximum deviation of the angle drift deviation of the hemispherical resonator gyro is 62.52; in the case of only compensating for the damping asymmetry error, the maximum deviation of the angle drift deviation is reduced to 9.72; after simultaneously compensating for the damping asymmetry error and the delay error, the maximum deviation of the angle drift deviation is further reduced to 1.2132, which is reduced by 51.5 times compared with the case of not compensating, and is further reduced by 8 times compared with the case of only compensating for the damping asymmetry error, verifying the correctness and effectiveness of the method proposed in the application.

[0111] In the description of the application, it should be understood that the terms "first", "second" are only for the purpose of description, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of indicated technical features. Therefore, the features defined with "first", "second" can be explicitly or implicitly included one or more of the features.

[0112] The part of the application not disclosed in detail belongs to the known technology in the art.

[0113] Although the above describes the specific embodiments of the application for the purpose of facilitating the understanding of the application by the person skilled in the art, it should be clear that the application is not limited to the scope of the specific embodiments, and for the person skilled in the art, it is obvious that various changes are within the spirit and scope of the application defined and determined by the appended claims, and all the application creations utilizing the concept of the application are included in the protection.

Claims

1. A method for jointly compensating for delay and damping asymmetry errors in a full-angle hemispherical gyroscope, characterized in that, Includes the following steps: S1. Set the self-precession excitation signal to excite the hemispherical gyroscope to vibrate, and obtain the self-precession excitation signal and the angular velocity measurement value signal output by the gyroscope; S2. The delay of the gyroscope is initially estimated using the maximum likelihood weighted cross-correlation delay estimation method to obtain the estimated delay; S3. Using the estimated delay, estimate the damping asymmetry error of the gyroscope through the recursive least squares method to obtain the estimated damping asymmetry error. S4. Using the estimated damping asymmetry error, re-estimate the gyroscope's delay to obtain the updated estimated delay; determine whether the updated estimated delay converges. If convergence fails, return to step S3 and use the updated estimated delay to re-estimate the damping asymmetry error of the gyroscope using the recursive least squares method; if convergence has been achieved, the final estimated delay is obtained. S5. The final estimated delay and damping asymmetry errors are compensated into the gyroscope's control system.

2. The method for joint compensation of delay and damping asymmetry error of a full-angle hemispherical gyroscope according to claim 1, characterized in that, The specific method for step S1 is as follows: S11. The control principle of the full-angle mode is represented by an elliptical orbit, and measurement noise is introduced to obtain the gyro angular velocity of the lower hemispherical resonant gyroscope at a certain moment. S12. Without external inertial angular velocity input, set the precession excitation signal to put the gyroscope into working state, and record the complete precession excitation signal and collect the complete angular velocity measurement signal output by the gyroscope. The angular velocity measurement signal output by the gyroscope from time k to time k+t is extracted to obtain the first angular velocity measurement signal with a duration of t; The precession excitation signal from time k to time k+t is extracted to obtain the first precession excitation signal with a duration of t.

3. The method for joint compensation of delay and damping asymmetry error of a full-angle hemispherical gyroscope according to claim 2, characterized in that, The specific method for step S2 is as follows: S21. Using the maximum likelihood weighted cross-correlation delay estimation method, calculate the weighted cross-correlation function between the first angular velocity measurement signal and the first self-precession excitation signal; S22. Calculate the estimated delay: Perform an inverse fast Fourier transform on the weighted cross-correlation function of the first angular velocity measurement signal and the first self-precession excitation signal, and then find the position of the maximum value of the inverse transform. The time corresponding to this position on the horizontal axis is the estimated delay. .

4. The method for joint compensation of delay and damping asymmetry error of a full-angle hemispherical gyroscope according to claim 3, characterized in that, The specific method for step S3 is as follows: S31. Utilizing the estimated delay , cut Time to The precession excitation signal at time t is used to obtain the second precession excitation signal with a duration of t; S32. Using the first angular velocity measurement signal and the second self-precession excitation signal, the estimated damping asymmetry error is solved by the least squares method.

5. The method for joint compensation of delay and damping asymmetry error of a full-angle hemispherical gyroscope according to claim 4, characterized in that, The specific method for step S32 is as follows: S321. Initialize the estimated parameter vector; S322. For each time k, in the estimated delay Above, construct the regression vector; S323. Based on the gyroscope angular velocity, the estimated parameter vector, and the regression vector, calculate the error between the actual measured value and the predicted value of the gyroscope angular velocity at time k. S324. Based on the regression vector, covariance matrix, and the error between the actual measured value and the predicted value of the gyroscope angular velocity at time k, the estimated parameter vector is re-estimated to obtain the updated estimated parameter vector at time k. S325, Update the covariance matrix.

6. The method for joint compensation of delay and damping asymmetry error of a full-angle hemispherical gyroscope according to claim 4, characterized in that, The specific method for step S4 is as follows: S41. Using the estimated damping asymmetry error, obtain the compensated gyro angular velocity at a certain moment; S42. Using the compensated gyroscope angular velocity at a certain moment, update the angular velocity of the first angular velocity measurement signal at each moment to obtain the second angular velocity measurement signal. S43. Using the maximum likelihood weighted cross-correlation delay estimation method, calculate the weighted cross-correlation function between the second angular velocity measurement signal and the second self-precession excitation signal; S44. Recalculate the estimated delay: Perform an inverse fast Fourier transform on the weighted cross-correlation function of the second angular velocity measurement signal and the second self-precession excitation signal, and then find the position of the maximum value of the inverse transform. The time corresponding to this position on the horizontal axis is the updated estimated delay. ; S45. Determine the delay of the update estimate. Convergence: Set a delay convergence threshold to determine the delay for updating the estimated delay. Delay compared to the last estimated Is the difference less than the delay convergence threshold? If not, return to step S3 and use the updated estimated delay. Re-estimate the damping asymmetry error; if so, update the estimated delay. The damping asymmetry error is the final estimated result.

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