A high-frequency injection-based online calibration method for assembly errors of hemispherical resonator gyroscopes

Abstract

The application discloses a kind of high-frequency injection-based hemispherical resonator gyro assembly error online calibration method, belongs to the field of inertial technology.Solve the assembly error online calibration method and exist the problem of complex calibration process, the strong influence on the zero drift stability of gyro and the limitation to working mode.The application extracts the high-frequency response in resonator by collecting the detection signal x h of X channel and the detection signal y h Of Y channel, and then demodulates two channel detection signals with high-frequency cosine reference signal respectively, so as to extract the high-frequency response in resonator.Subsequently, according to the amplitude of high-frequency cosine given signal of X channel and Y channel, and the signal correlation model demodulated to identify the assembly error parameters of gyro in real time, finally realizes the online calibration of assembly error according to the identification result.The method can be applied to the online calibration process of hemispherical resonator gyro assembly error.

Description

TECHNICAL FIELD

[0001] The present application belongs to the technical field of inertial technology. BACKGROUND

[0002] The hemispherical resonator gyroscope is an axisymmetric vibration gyroscope based on the Coriolis effect. Compared with the traditional rotor gyroscope and two-optical gyroscope, it has the characteristics of small size, high precision, long service life and low power consumption, and has successfully applied in the fields of land, space, navigation, aviation. The control and detection of the hemispherical resonator gyroscope are realized by eight equally divided flat electrodes on the electrode base, so the symmetry of the two channels is closely related to the assembly level of the hemispherical resonator gyroscope. During the assembly process of the hemispherical resonator and the electrode base, tilt error and eccentric error will be generated, which will further cause the electrode gap and angle interval of the eight flat electrodes to be inconsistent, and further affect the gain error and bias angle error of the two channels. With the change of environmental temperature, thermal expansion of quartz material and electrode solder will further change the assembly error of the gyroscope, including the gain error and bias angle error of the two channels.

[0003] The existing assembly error online calibration method is to make the standing wave produce periodic precession by using virtual precession control force, and to identify the gain error and bias angle error of the two channels according to the relationship between the azimuth angle of the standing wave and the amplitude control force and the slowly varying variable signal. However, this method needs to construct a virtual precession control loop of the gyroscope, which undoubtedly increases the complexity of the system and the complexity of the calibration process, and the fluctuation of the virtual precession will also have a severe impact on the zero bias stability of the gyroscope. Moreover, this calibration method can only be applied to the hemispherical resonator gyroscope in full angle mode, and cannot be applied to the hemispherical resonator gyroscope in force balance mode. Therefore, there is an urgent need for an online calibration method for assembly error which is simple, has little impact on the performance of the gyroscope, and has no restriction on the working mode. SUMMARY

[0004] The purpose of the present application is to solve the problems of complex calibration process, severe impact on the zero bias stability of the gyroscope and restriction on the working mode in the online calibration method for assembly error. The present application provides an online calibration method for hemispherical resonator gyroscope assembly error based on high-frequency injection.

[0005] An online calibration method for hemispherical resonator gyroscope assembly error based on high-frequency injection, the online calibration method comprising the following steps:

[0006] Step 1, power on the hemispherical resonator gyroscope to make the hemispherical resonator gyroscope in a stable working state;

[0007] Step 2, judge whether the power-on start time reaches the start online calibration time, the result is yes, jump to step 3, otherwise, jump to step 1;

[0008] Step 3, use a high-frequency cosine reference signal Vhc the detection signal x of the X channel of the hemispherical resonator gyroscope h and the detection signal y of the Y channel h high frequency demodulation is performed to obtain the X channel high frequency component cosine signal C hx and the Y channel high frequency component cosine signal C hy

[0009] wherein the frequency of the high frequency cosine reference signal V hc is ω h , ω h >> ω, ω being the resonant frequency of the resonator;

[0010] Step 4, the initial value of k is 1, the initial value of the assembly error is set to 0, the amplitude U xc of the X channel high frequency cosine given signal and the amplitude U yc of the Y channel high frequency cosine given signal are taken as the observation quantities, the C hx and C hy demodulated by the high frequency are taken as the expected output quantities, and the assembly error on-line identification algorithm is used to realize the on-line identification of the assembly error; the assembly error includes the channel gain error k yx and the bias angle error α;

[0011] Step 5, it is judged whether the assembly error identified in the kth round converges, and if yes, the process jumps to Step 6, otherwise, k=k+1, and the process jumps to Step 4;

[0012] Step 6, the detection signals of the X channel and the Y channel of the hemispherical resonator gyroscope and the control signals of the X channel and the Y channel of the hemispherical resonator gyroscope are compensated by using the assembly error identified in the kth round, and the on-line calibration of the assembly error of the hemispherical resonator gyroscope is completed.

[0013] Preferably, the condition for judging whether the assembly error identified in the kth round converges in Step 5 is that:

[0014] when the difference between the channel gain error k yx identified in the kth round and the channel gain error k hx identified in the (k-1)th round and the difference between the bias angle error α identified in the kth round and the bias angle error α identified in the (k-1)th round are both less than the corresponding convergence threshold, it is determined that the assembly error identified in the kth round converges, otherwise, the assembly error identified in the kth round does not converge.

[0015] Preferably, the implementation manner of obtaining the X channel high frequency component cosine signal C hx and the Y channel high frequency component cosine signal C hy in Step 3 includes:

[0016]

[0017] wherein LPF(·) is a low-pass filtering operation, k x is the X channel detection gain, k y is the Y channel detection gain, x hc and y hc are high frequency cosine components of the detection signals of the X channel and the Y channel, respectively.

[0018] Preferably, the implementation of the online identification of the assembly error in step 4 is implemented by using an assembly error identification algorithm, which includes the following steps:

[0019] Step 41, according to U xc and U yc as the observation quantities, and C hx and C hy as the expected output quantities, a correlation model is established:

[0020]

[0021] wherein,

[0022] In the above formula, A is a detection error matrix, E is a driving error matrix, k x is the X channel detection gain, k y is the Y channel detection gain, K x is the X channel control gain, K y is the Y channel control gain,

[0023] Step 42, the correlation model is converted into a discrete product form:

[0024] C(k)=U(k)β(k);

[0025] wherein:

[0026]

[0027]

[0028]

[0029] C(k) is the expected output vector at the kth sampling time, U(k) is the observation vector at the kth sampling time, β(k) is the parameter vector at the kth sampling time, β1(k) is the first row and first column element in β(k), β2(k) is the second row and first column element in β(k), β3(k) is the third row and first column element in β(k), k is the sampling time sequence number, k=1, 2, 3……, C hx (k) is the discrete form of C hx , C hy (k) is the discrete form of C hy , Uxc (k) is a discrete form of U xc (k) is a discrete form of U yc (k) is a discrete form of U xc (k) is a discrete form of k x (k) is a discrete form of k x (k) is a discrete form of K x (k) is a discrete form of K x (k) is a discrete form of k y (k) is a discrete form of k y (k) is a discrete form of K y (k) is a discrete form of K y (k) is a discrete form of k

[0030] Step 43, according to U(k) in step 42, the gain vector H(k) and the covariance matrix P(k) of the assembly error identification algorithm corresponding to the kth sampling time are obtained;

[0031] Step 44, according to C(k) and U(k) obtained in step 41 and H(k) obtained in step 43, the parameter vector β(k) of the kth sampling time is obtained;

[0032] Step 45, according to β1(k), β2(k) and β3(k) in β(k), the channel gain error k yx and the deflection angle error α identified in the kth round are obtained, and the online identification of the assembly error is completed;

[0033]

[0034]

[0035] Preferably, in step 43,

[0036]

[0037]

[0038] wherein P(0) = I, I is a unit matrix, η is a forgetting factor, η is selected in the range of (0, 1], and P(k-1) is the covariance matrix corresponding to the k-1th sampling time.

[0039] Preferably, in step 44, β(k) = β(k-1) + H(k)(C(k) - U(k)β(k-1));

[0040] wherein β(k-1) is the parameter vector of the k-1th sampling time,

[0041] Preferably, the implementation of compensating the detection signals of the X channel and the Y channel of the hemispherical resonator gyroscope in step 6 by using the assembly error recognized in the kth round is as follows:

[0042]

[0043] x com The detection signal of the X channel of the compensated hemispherical resonator gyroscope is y com The detection signal of the Y channel of the compensated hemispherical resonator gyroscope is y

[0044] Preferably, the implementation of compensating the control signals of the X channel and the Y channel of the hemispherical resonator gyroscope in step 6 by using the assembly error recognized in the kth round includes:

[0045] The high-frequency cosine reference signal V hc , the amplitude U xc of the X channel high-frequency cosine given signal, and the amplitude U yc of the Y channel high-frequency cosine given signal are superimposed on the X channel control signal V x and the control signal V y of the Y channel to obtain the high-frequency control signal V x1 of the X channel and the high-frequency control signal V y1 of the Y channel; wherein,

[0046]

[0047] Then, the V x1 and V y1 are compensated by using the assembly error recognized in the kth round to obtain the compensated control signal V xcom of the X channel and the compensated control signal V ycom of the Y channel.

[0048]

[0049] Preferably, the stable working state in step 1 is that the amplitude of the resonator of the hemispherical resonator gyroscope remains constant, and the orthogonal wave of the resonator is suppressed to zero.

[0050] Preferably, ω h > 10ω.

[0051] Advantages of the present application:

[0052] The hemispherical resonator gyroscope assembly error online calibration method based on high-frequency injection provided by the present application only relies on the detection signal x h of the X channel and the detection signal y h of the Y channel of the hemispherical resonator gyroscope in the stable working state, and the present application uses the high-frequency response of the resonator to extract x h and yh According to the assembly error identification result, the gain error and the angle error of the detection and control channel are calibrated, and finally the temperature change does not affect the nonlinearity of the gyro scale factor.

[0053] Compared with the prior art of using virtual precession to realize online calibration of assembly error, the high-frequency reference signal is superimposed in the control voltage, and the assembly error is extracted from the high-frequency component of the vibration signal of the resonator. This method does not need to construct a virtual precession control loop of the gyro, and the position of the standing wave azimuth angle does not affect the identification result, so the influence of the virtual precession on the gyro zero bias stability and the working mode of the gyro is avoided. The calibration process of this method is simple, the hardware complexity is low, and the position of the azimuth angle is not limited, so it can be widely applied to the full-angle mode and force balance mode of the hemispherical resonator gyro. BRIEF DESCRIPTION OF DRAWINGS

[0054] Figure 1 is a structural schematic diagram of a control circuit for driving and controlling the hemispherical resonator gyro without virtual precession in the prior art; wherein x h and y h are the detection signals of the X channel and the Y channel of the hemispherical resonator gyro, that is, the signals amplified by the pre-buffering amplification circuit to the vibration signals output by the X channel and the Y channel of the hemispherical resonator gyro; V s and V c are the sine and cosine reference signals output by the phase-locked loop, E is the total energy of the gyro, Q is the quadrature of the gyro, L is the phase-locked loop control quantity, C x , C y , S x , S y are four slowly varying signals, V x and V y are the control signals of the X channel and the Y channel.

[0055] Figure 2 is a principle schematic diagram after introducing the online calibration method of the hemispherical resonator gyro assembly error based on high-frequency injection in Figure 1 ;

[0056] Figure 3 is a flowchart of the online calibration method of the hemispherical resonator gyro assembly error based on high-frequency injection. DETAILED DESCRIPTION

[0057] With reference to the drawings and the embodiments of the present application, the technical solutions in the embodiments of the present application will be described clearly and completely. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments of the present application. Based on the embodiments of the present application, all the other embodiments obtained by those skilled in the art without creative effort belong to the scope of the present application.

[0058] It should be noted that the embodiments in the present application and the features in the embodiments can be combined with each other without conflict.

[0059] Specific implementation Figure 2 and Figure 3 The present embodiment is described. The online calibration method of the hemispherical resonator gyro based on high-frequency injection includes the following steps:

[0060] Step 1, power on and start the hemispherical resonator gyro, so that the hemispherical resonator gyro is in a stable working state; in specific application, the stable working state is that the amplitude of the resonator of the hemispherical resonator gyro remains constant, and the orthogonal wave of the resonator is suppressed to zero;

[0061] Step 2, determine whether the power-on start time reaches the online calibration start time, and if the result is yes, jump to step 3, otherwise, jump to step 1; the online calibration start time is a time threshold, which is to further ensure that the hemispherical resonator gyro is in a stable working state, and to provide accurate data basis for subsequent accurate calibration;

[0062] Step 3, demodulate the two-channel vibration signals by using a high-frequency reference signal to realize the extraction of the high-frequency component in the detection signal: use a high-frequency cosine reference signal V hc to demodulate the detection signal x h of the X channel and the detection signal y h of the Y channel of the hemispherical resonator gyro, so as to obtain the X channel high-frequency component cosine signal C hx and the Y channel high-frequency component cosine signal C hy ;

[0063] Wherein, the frequency of the high-frequency cosine reference signal V hc is ω h , ω h >> ω, and ω is the resonant frequency of the resonator; in order to avoid the influence of the high-frequency signal on the resonant amplitude, generally, the frequency ω h of the high-frequency cosine reference signal V hc is greater than 10 times the resonant frequency ω, that is: ω h > 10ω;

[0064] Step 4, the kth round of identification, the initial value of k is 1, set the initial value of assembly error to 0, the amplitude U of the X channel high frequency cosine given signal xc and the amplitude U of the Y channel high frequency cosine given signal yc As an observation, the high frequency demodulated C hx and C hy As an expected output, the online identification of the assembly error is realized by using an assembly error identification algorithm; the assembly error includes the channel gain error k yx and the angle error a.

[0065] Step 5, judge whether the assembly error identified in the kth round converges, if yes, jump to step 6, otherwise, k=k+1, jump to step 4.

[0066] Step 6, compensate the detection signals of the X channel and the Y channel of the hemispherical resonator gyroscope, and the control signals of the X channel and the Y channel of the hemispherical resonator gyroscope by using the assembly error identified in the kth round, and complete the online calibration of the assembly error of the hemispherical resonator gyroscope.

[0067] Further, the condition for judging whether the assembly error identified in the kth round converges in step 5 is:

[0068] When the difference between the channel gain error k yx identified in the kth round and the channel gain error k hx identified in the (k-1)th round, and the difference between the angle error a identified in the kth round and the angle error a hy identified in the (k-1)th round are all less than the corresponding convergence threshold, it is determined that the assembly error identified in the kth round converges, otherwise, the assembly error identified in the kth round does not converge.

[0069] Referring to Figure 2 Further, the implementation of the X channel high frequency component cosine signal C hx and the Y channel high frequency component cosine signal C hy in step 3 includes:

[0070]

[0071] Wherein, LPF(·) is a low-pass filtering operation, k x is the X channel detection gain, k y is the Y channel detection gain, x hc and y hc are high frequency cosine components of the detection signals of the X channel and the Y channel respectively.

[0072] Further, the implementation of the online identification of the assembly error in step 4 includes:

[0073] Step 41, according to the U xc and U ycAnd C as the expected output hx and C hy Establish a correlation model:

[0074]

[0075] in,

[0076] In the above formula, A is the detection error matrix, E is the driving error matrix, and k x For the detection gain of the X channel, k y For the Y-channel detection gain, K x K controls the gain of channel X. y For Y-channel control gain,

[0077] Step 42: Convert the correlation model into a discrete product form:

[0078] C(k) = U(k)β(k);

[0079] in:

[0080]

[0081]

[0082]

[0083] C(k) is the expected output vector at the k-th sampling time, U(k) is the observation vector at the k-th sampling time, β(k) is the parameter vector at the k-th sampling time, β1(k) is the element in the first row and first column of β(k), β2(k) is the element in the second row and first column of β(k), β3(k) is the element in the third row and first column of β(k), and k is the sampling time sequence number, k = 1, 2, 3, ..., C hx (k) is C hx The discrete form of C hy (k) is C hy The discrete form of U xc (k) is U xc The discrete form of U yc (k) is U xc Discrete form, k x (k) is k x The discrete form, K x (k) is K x Discrete form, k y (k) is k y The discrete form, K y (k) is K y The discrete form of α, where α(k) is the discrete form of α;

[0084] Step 43, according to U(k) in step 42, the gain vector H(k) and the covariance matrix P(k) of the assembly error identification algorithm corresponding to the k th sampling time are obtained;

[0085]

[0086]

[0087] Wherein, P(0) = I, I is a unit matrix, P(k-1) is the covariance matrix corresponding to the k-1 th sampling time; η is a forgetting factor, η is selected in the range of (0, 1], when the forgetting factor is small, the algorithm converges fast, but the steady state is easy to be affected by noise; on the contrary, the larger the value of the forgetting factor, the slower the algorithm converges, but the steady state effect is not easy to be disturbed by noise;

[0088] Step 44, according to C(k) and U(k) obtained in step 41, and H(k) obtained in step 43, the parameter vector β(k) of the k th sampling time is obtained;

[0089] β(k) = β(k-1) + H(k)(C(k)-U(k)β(k-1));

[0090] Wherein, β(k-1) is the parameter vector of the k-1 th sampling time,

[0091] Step 45, according to β1(k), β2(k) and β3(k) in β(k), the channel gain error k yx And the angle error α of the k th round of identification are obtained, and the online identification of the assembly error is completed;

[0092]

[0093]

[0094] Referring to Figure 2 Further, the implementation mode of compensating the detection signals of the X channel and the Y channel of the hemispherical resonator gyroscope by using the assembly error identified in step 6 is:

[0095]

[0096] x com The detection signal of the X channel of the compensated hemispherical resonator gyroscope, y com The detection signal of the Y channel of the compensated hemispherical resonator gyroscope.

[0097] Referring to Figure 2Further, the implementation mode of compensating the control signals of the X channel and the Y channel of the hemispherical resonator gyro by using the assembly error recognized in the kth round in step 6 comprises:

[0098] The high-frequency cosine reference signal V hc , the amplitude U xc of the high-frequency cosine given signal of the X channel, and the amplitude U yc of the high-frequency cosine given signal of the Y channel are superimposed on the control signals V x and V y of the X channel and the Y channel, respectively, to obtain the high-frequency control signals V x1 and V y1 of the X channel and the Y channel, respectively; wherein,

[0099]

[0100] The high-frequency control signals V x1 and V y1 are compensated by using the assembly error recognized in the kth round, to obtain the compensated control signals V xcom and V ycom of the X channel and the Y channel, respectively;

[0101]

[0102] Principle analysis: the detection signals x h and y h of the X channel and the Y channel are collected, and then the two-channel detection signals are demodulated with the high-frequency cosine reference signal, so that the high-frequency response in the resonator is extracted. Subsequently, the assembly error parameters of the gyro are recognized in real time according to the amplitude of the high-frequency cosine given signal of the X channel and the Y channel and the correlation model established by the demodulated signals, and finally the online calibration of the assembly error is realized according to the recognition result.

[0103] Although the present application is described herein with reference to particular embodiments, it is to be understood that these examples are merely illustrative of principles and applications of the present application. It should therefore be understood that numerous modifications can be made to the illustrative embodiments and that other arrangements can be devised without departing from the spirit and scope of the present application as defined by the appended claims. It should be understood that the features described in connection with one embodiment can be used in conjunction with other embodiments described herein. It should be understood that the features described in connection with one embodiment can be used in conjunction with other embodiments described herein.

Claims

1. A method for online calibration of assembly errors of a hemispherical resonant gyroscope based on high-frequency injection, characterized in that, The online calibration method includes the following steps: Step 1: Power on the hemispherical resonator to start it and bring it into a stable working state; Step 2: Determine whether the power-on startup time has reached the online calibration start time. If yes, proceed to Step 3; otherwise, proceed to Step 1. Step 3: Utilize a high-frequency cosine reference signal Detection signal of the X channel of a hemispherical resonant gyroscope and the detection signal of the Y channel High-frequency demodulation is performed to obtain the high-frequency cosine signal of the X channel. and the Y-channel high-frequency component cosine signal ; Among them, the high-frequency cosine reference signal The frequency is , , The resonant frequency of the harmonic oscillator; Step 4, the Wheel identification, The initial value is 1, the initial value of the assembly error is set to 0, and the amplitude of the high-frequency cosine given signal of the X channel is set to 1. The amplitude of the high-frequency cosine given signal in the Y channel As an observable, high-frequency demodulation and As the desired output, an assembly error identification algorithm is used to identify assembly errors online; the assembly errors include channel gain errors. and deflection angle error ; The implementation methods for online identification of assembly errors using assembly error identification algorithms include: Step 41: Based on the observed quantities and and as the expected output and Establish a correlation model: ； in, ; In the above formula, For the detection error matrix, For the driving error matrix, For X channel detection gain, For Y-channel detection gain, The gain is controlled for the X channel. For Y-channel control gain, ; Step 42: Convert the correlation model into a discrete product form: ； in: For the first The expected output vector at each sampling time point, For the first The observation vector at each sampling time, For the first The parameter vector at each sampling time point for The element in the first row and first column of the middle, for The element in the second row and first column, for The element in the third row and first column, This is the sampling time sequence number. , for discrete form, for discrete form, for discrete form, for discrete form, for discrete form, for discrete form, for discrete form, for discrete form, for Discrete form; Step 43, according to step 42 Find the first... The gain vector of the assembly error identification algorithm corresponding to each sampling time point Covariance Matrix ; Step 44, based on the results obtained in step 41 and and the results obtained in step 43 Find the first... Parameter vector at each sampling time point ; Step 45, according to In , and , obtained the Channel gain error identified by wheel and deflection angle error This enables online identification of assembly errors. Step 5, determine the first If the assembly error identified by the wheel converges, and the result is yes, proceed to step 6; otherwise, Proceed to step 4; Step 6, using the first The assembly error identified by the wheel is used to compensate for the detection signals of the X and Y channels of the hemispherical resonator gyroscope, as well as the control signals of the X and Y channels of the hemispherical resonator gyroscope, thus completing the online calibration of the assembly error of the hemispherical resonator gyroscope.

2. The method for online calibration of assembly error of a hemispherical resonator gyroscope based on high-frequency injection according to claim 1, characterized in that, In step 5, determine the first The condition for convergence of the assembly errors identified by the wheel is: No. Wheel and the first Channel gain error obtained by round identification Inter-difference, and the first Wheel and the first The deviation angle error obtained by wheel identification When all inter-interval differences are less than the corresponding convergence threshold, the first inter-interval is determined to be less than the second inter-interval. The assembly error identified by the first round converges; otherwise, the first... The assembly error obtained by wheel identification does not converge.

3. The method for online calibration of assembly error of a hemispherical resonator gyroscope based on high-frequency injection according to claim 1, characterized in that, Step 3 yields the cosine signal of the high-frequency component of the X channel. and the Y-channel high-frequency component cosine signal The implementation methods include: ； in, This is a low-pass filter operation. For X channel detection gain, For Y-channel detection gain, and These are the high-frequency cosine components of the detection signals for the X and Y channels, respectively.

4. The method for online calibration of assembly error of a hemispherical resonator gyroscope based on high-frequency injection according to claim 1, characterized in that, In step 43, ； ； in, , It is the identity matrix. Forgetting factor, Select within the range (0,1). For the first The covariance matrix corresponding to each sampling time point.

5. The method for online calibration of assembly error of a hemispherical resonator gyroscope based on high-frequency injection according to claim 1, characterized in that, In step 44, ; in, For the first The parameter vector at each sampling time point .

6. The method for online calibration of assembly error of a hemispherical resonator gyroscope based on high-frequency injection according to claim 1, characterized in that, In step 6, the first The method for compensating the X and Y channel detection signals of the hemispherical resonant gyroscope based on the assembly errors identified by the wheel is as follows: ； The detection signal of the X channel of the compensated hemispherical resonant gyroscope. The detection signal of the Y channel of the compensated hemispherical resonant gyroscope.

7. The method for online calibration of assembly error of a hemispherical resonator gyroscope based on high-frequency injection according to claim 1, characterized in that, In step 6, the first The methods for compensating the X and Y channel control signals of the hemispherical resonator gyroscope based on the assembly errors identified by the wheel include: High-frequency cosine reference signal The amplitude of the high-frequency cosine given signal in the X channel The amplitude of the high-frequency cosine given signal in the Y channel Superimposed on the X channel control signal and the control signal of the Y channel The high-frequency control signal of the X channel is obtained. and the high-frequency control signal of the Y channel ;in, ； Reuse of the first Assembly errors identified by the wheel and Compensation is performed to obtain the compensated control signal for the X channel. and the control signal of the compensated Y channel ; 。 8. The method for online calibration of assembly error of a hemispherical resonator gyroscope based on high-frequency injection according to claim 1, characterized in that, In step 1, the stable operating state is that the amplitude of the harmonic oscillator of the hemispherical resonant gyroscope remains constant, and the suppression of the orthogonal wave of the harmonic oscillator is zero.

9. The method for online calibration of assembly error of a hemispherical resonator gyroscope based on high-frequency injection according to claim 1, characterized in that, 。

Images