On-line calibration method for phase error of control loop of hemispherical resonator gyro

Abstract

The application relates to an online calibration method for phase error of a control loop of a hemispherical resonator gyro, and belongs to the technical field of inertial instrument control. The application solves the problems of poor environmental adaptability and complicated calculation of the existing online calibration method for phase error of a control loop of a hemispherical resonator gyro. A given high-frequency signal is superimposed in a resonator control signal, then a high-frequency reference signal is used to demodulate a detection signal to extract the sine and cosine components of the high-frequency signal of the resonator. Finally, the phase error of the control loop is obtained through an online identification algorithm according to the high-frequency control signal and the high-frequency demodulation result, and the target phase locking phase of a phase-locked loop is adjusted in real time according to the identification result, so that the online calibration for the phase error of the control loop of the hemispherical resonator gyro is realized. The application is mainly used for online calibration for the phase error of the control loop of the hemispherical resonator gyro.

Description

Technical Field

[0001] This invention belongs to the field of inertial instrument control technology. Background Technology

[0002] Hemispherical resonant gyroscopes measure angular rate by measuring the Coriolis effect as the resonator rotates around its central axis. They offer numerous advantages, including simple structure, high precision, long lifespan, and short start-up time, leading to their widespread application in marine, land, air, and space applications. Hemispherical resonant gyroscopes typically use a charge amplifier to convert the detection signal generated by the resonator's vibration into a voltage signal. This amplifier consists of resistors, capacitors, and operational amplifiers. Changes in ambient temperature alter the performance of the electronic components in the buffer amplifier, thereby changing the amplitude and phase frequency characteristics of the detection circuit. Simultaneously, the resonator's vibration frequency changes systematically with temperature. These temperature-induced error factors all contribute to variations in the phase error of the detection circuit at the resonant frequency.

[0003] In summary, as the running time of the hemispherical resonator gyroscope increases, the phase error of the control loop formed by the matching control circuit without virtual precession control connected to the hemispherical resonator gyroscope will be affected by the ambient temperature; see [link to relevant documentation]. Figure 1 V in the figure c and V s These are the cosine and sine reference signals output by the phase-locked loop, which have the same frequency as the detected signal, respectively. x C y S x S y Both signals are slow-variable signals. E is used as the gyroscope amplitude control quantity to keep the vibration amplitude of the resonator constant; Q is used as the quadrature control quantity to eliminate the phase difference between the two channels; the arctangent of L and M can be used to obtain the phase difference between the reference signal and the detection signal generated by the resonator vibration, and this difference is used as the control quantity of the phase-locked loop to generate the reference signal V. c and V s The reference signal generated by the phase-locked loop is affected by the phase error of the control loop, which in turn affects the control performance of the gyroscope. Therefore, an online calibration method must be used to eliminate the influence of the phase error on the phase-locked loop.

[0004] Existing technologies include online calibration methods for the phase error of the control loop of a hemispherical resonator gyroscope. These methods require constructing the transfer function of the hemispherical resonator gyroscope and using the amplitude-frequency and phase-frequency characteristic curves of the driving mode to obtain the phase error of the control loop. The entire calculation process is cumbersome. Furthermore, with changes in ambient temperature, the frequency, quality factor, and frequency fragmentation of the resonator will change drastically, thus altering the transfer function of the hemispherical resonator gyroscope. Consequently, existing methods have poor environmental adaptability. Therefore, these problems urgently need to be addressed. Summary of the Invention

[0005] The application aims to solve the problems of poor environmental adaptability and complicated calculation of the existing online calibration method for the control loop phase error of a hemispherical resonator gyroscope, and provides an online calibration method for the control loop phase error of a hemispherical resonator gyroscope.

[0006] The online calibration method for the control loop phase error of a hemispherical resonator gyroscope comprises the following steps:

[0007] Step 1: generating high-frequency sine and cosine reference signals by a high-frequency signal generation module, generating high-frequency control signals of the excitation electrodes of the X channel and the Y channel of the hemispherical resonator gyroscope according to the high-frequency sine and cosine reference signals and the amplitudes of four given high-frequency signals, driving and controlling the excitation electrodes of the X channel and the Y channel respectively, so that the hemispherical resonator gyroscope is in a stable working state; at this time, the pre-buffer amplification circuit in the matched control circuit without virtual precession control connected with the hemispherical resonator gyroscope amplifies the detection signals output by the detection electrodes of the X channel and the Y channel of the hemispherical resonator gyroscope;

[0008] wherein the high-frequency sine and cosine reference signals have the same frequency, and both are ω h , ω h >> ω, ω is the resonant frequency of the resonator;

[0009] Step 2: high-frequency demodulating the X channel and Y channel amplified detection signals output by the pre-buffer amplification circuit in the matched control circuit without virtual precession control connected with the hemispherical resonator gyroscope by using the generated high-frequency sine and cosine reference signals, so as to obtain the high-frequency component sine and cosine signals in the X channel amplified detection signals and the high-frequency component sine and cosine signals in the Y channel amplified detection signals;

[0010] Step 3: k-th round identification, the initial value of k is 1, setting the initial value of the control loop phase error as 0, taking the amplitudes of the four given high-frequency signals as the observation quantity, taking the high-frequency component sine and cosine signals demodulated from the X channel and Y channel amplified detection signals as the expected output quantity, and using a phase error identification algorithm to realize online identification of the control loop phase error;

[0011] Step 4: judging whether the difference between the phase errors obtained by adjacent two rounds of identification is less than a set threshold value, if yes, jumping to step 5, otherwise, k=k+1, jumping to step 3;

[0012] Step 5: taking the phase error obtained by the k-th round of identification as the target phase-locked phase of the phase-locked loop in the matched control circuit without virtual precession control connected with the hemispherical resonator gyroscope, so as to realize online calibration of the control loop phase error of the hemispherical resonator gyroscope.

[0013] Preferably, in step 1, the stable working state is that the amplitude of the resonator of the hemispherical resonator gyroscope is kept constant, and the quadrature wave of the resonator is zero.

[0014] Preferably, in step 1, the high-frequency control signals of the drive electrodes of the X channel and the Y channel of the hemispherical resonator gyroscope are generated in the following manner:

[0015]

[0016] wherein V x1 and V y1 are the high-frequency control signals of the drive electrodes of the X channel and the Y channel, respectively, V x and V y are the original control signals of the drive electrodes of the X channel and the Y channel, respectively, U xc , U xs , U yc and U yc are the amplitudes of the first to fourth given high-frequency signals, respectively, and V hs and V hc are high-frequency sine and cosine reference signals, respectively.

[0017] Preferably, the amplitudes of the four given high-frequency signals are different.

[0018] Preferably, the amplified detection signals of the X channel and the Y channel output by the pre-buffering amplification circuit are as follows:

[0019]

[0020] wherein x h and y h are the amplified detection signals of the X channel and the Y channel output by the pre-buffering amplification circuit, respectively, a represents the amplitude of the main standing wave, q represents the amplitude of the quadrature wave, K is the detection gain, t is the time, θ is the azimuth angle of the standing wave, x hc is the high-frequency cosine component of the detection signal output by the X channel of the hemispherical resonator gyroscope, x hs is the high-frequency sine component of the detection signal output by the X channel of the hemispherical resonator gyroscope, y hs is the high-frequency sine component of the detection signal output by the Y channel of the hemispherical resonator gyroscope, and y hc is the high-frequency cosine component of the detection signal output by the Y channel of the hemispherical resonator gyroscope, is the phase error of the control loop, is the phase difference between the amplified detection signal of the X channel or the Y channel output by the pre-buffering amplification circuit and the detection signal of the corresponding channel before amplification at the frequency ω h .

[0021] Preferably, the high-frequency components in the X-channel amplified detection signal and the high-frequency components in the Y-channel amplified detection signal in step 2 are realized as follows:

[0022]

[0023] In the above formula, LPF(·) is a low-pass filtering operation, V hs and V hc are high-frequency sine and cosine reference signals, K is a detection gain, is the phase difference between the X-channel or Y-channel amplified detection signal output by the pre-buffering amplification circuit and the detection signal before channel amplification at the frequency ω h ; C hx is the high-frequency component cosine signal in the X-channel amplified detection signal demodulated by the high frequency, C hy is the high-frequency component cosine signal in the Y-channel amplified detection signal demodulated by the high frequency, S hx is the high-frequency component sine signal in the X-channel amplified detection signal demodulated by the high frequency, and S hy is the high-frequency component sine signal in the Y-channel amplified detection signal demodulated by the high frequency; x hc is the high-frequency cosine component of the detection signal output by the X-channel of the hemispherical resonator gyroscope, x hs is the high-frequency sine component of the detection signal output by the X-channel of the hemispherical resonator gyroscope, y hs is the high-frequency sine component of the detection signal output by the Y-channel of the hemispherical resonator gyroscope, and y hc is the high-frequency cosine component of the detection signal output by the Y-channel of the hemispherical resonator gyroscope.

[0024] Preferably, the specific process of realizing the online identification of the phase error of the control loop in step 3 is as follows:

[0025] Step 30, according to the relative relationship of x hs , y hs , x hc , y hc , S hx , S hy , C hx , and C hy , the transformation matrix D is solved, specifically as follows:

[0026]

[0027] wherein, is the phase difference between the X-channel or Y-channel amplified detection signal output by the pre-buffering amplification circuit and the detection signal before channel amplification at the frequency ω h ; Chx C is the high frequency component cosine signal in the amplified detection signal of the X channel after high frequency demodulation hy S is the high frequency component cosine signal in the amplified detection signal of the Y channel after high frequency demodulation hx S is the high frequency component sine signal in the amplified detection signal of the X channel after high frequency demodulation hy S is the high frequency component sine signal in the amplified detection signal of the Y channel after high frequency demodulation hc x is the high frequency cosine component of the detection signal output by the X channel of the hemispherical resonator gyroscope hs y is the high frequency sine component of the detection signal output by the X channel of the hemispherical resonator gyroscope hs y is the high frequency sine component of the detection signal output by the Y channel of the hemispherical resonator gyroscope hc x is the high frequency cosine component of the detection signal output by the Y channel of the hemispherical resonator gyroscope

[0028] Step 31, a correlation model is established according to the amplitudes of four given high frequency signals as observation quantities and the high frequency component sine and cosine signals in the amplified detection signals of the X channel and the Y channel after high frequency demodulation as expected output quantities:

[0029]

[0030] wherein U xc , U xs , U yc and U yc are the amplitudes of the first to fourth given high frequency signals, κ is a control gain, and K is a detection gain;

[0031] Step 32, the correlation model is converted into a discrete product form: C(k) = U(k)β(k);

[0032] wherein

[0033]

[0034]

[0035]

[0036] wherein C(k) is an expected output vector at the kth sampling time, U(k) is an observation vector at the kth sampling time, β(k) is a parameter vector at the kth sampling time, k is a sampling time serial number, k = 1, 2, 3, …, C hx (k) is the high frequency component cosine signal in the amplified detection signal of the X channel after high frequency demodulation corresponding to the kth sampling time hy(k) is the high frequency component cosine signal in the high frequency demodulated Y channel amplified detection signal corresponding to the kth sampling time, S hx (k) is the high frequency component cosine signal in the high frequency demodulated Y channel amplified detection signal corresponding to the kth sampling time, S hy (k) is the high frequency component cosine signal in the high frequency demodulated Y channel amplified detection signal corresponding to the kth sampling time, S xc (k) is the high frequency component cosine signal in the high frequency demodulated Y channel amplified detection signal corresponding to the kth sampling time, S xs (k) is the high frequency component cosine signal in the high frequency demodulated Y channel amplified detection signal corresponding to the kth sampling time, S yc (k) is the high frequency component cosine signal in the high frequency demodulated Y channel amplified detection signal corresponding to the kth sampling time, S yc (k) is the high frequency component cosine signal in the high frequency demodulated Y channel amplified detection signal corresponding to the kth sampling time, S

[0037] Step 33, according to U(k) in step 32, the gain vector H(k) and the covariance matrix P(k) of the phase error identification algorithm corresponding to the kth sampling time are obtained;

[0038] Step 34, according to C(k) and U(k) obtained in step 32, and H(k) obtained in step 33, the parameter vector β(k) of the kth sampling time is obtained;

[0039] Step 35, according to β(k), the control loop phase error is obtained

[0040]

[0041] wherein, β1(k) is the first row first column element of β(k), and β2(k) is the second row first column element of β(k);

[0042] Step 36, according to and ω h the control loop phase error is obtained

[0043] Preferably, in step 33,

[0044]

[0045]

[0046] 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.

[0047] Preferably, in step 34, β(k) = β(k-1) + H(k)(C(k)-U(k)β(k-1));

[0048] Wherein, β(k-1) is the parameter vector of the k-1th sampling time,

[0049] Advantages of the present application:

[0050] The present application uses the high frequency component of the detection signal generated by the vibration of the harmonic oscillator to extract the phase error of the control loop, thus not having negative effects on the normal amplitude control loop and the quadrature control loop of the gyroscope. The method does not depend on external equipment such as turntable, phase meter, signal generator, and does not depend on the transfer function of the hemispherical resonator gyroscope, and the amount of data required is small, so the self-calibration process is simple, and the calibration process is not limited by the working mode of the gyroscope and the environment, and can still achieve self-calibration in a changing environment, and can be widely applied to the hemispherical resonator gyroscope in force balance mode or full angle mode.

[0051] The present application proposes an online calibration method for the phase error of the control loop of the hemispherical resonator gyroscope, which has strong environmental adaptability, and the phase error of the control loop can be calibrated in real time with the change of the environmental temperature, thereby reducing the phase error between the reference signal and the detection signal. BRIEF DESCRIPTION OF DRAWINGS

[0052] Figure 1 is the connection relationship diagram of the hemispherical resonator gyroscope and the matching control circuit without virtual precession control in the prior art;

[0053] Figure 2 is the principle diagram of the online calibration method for the phase error of the control loop of the hemispherical resonator gyroscope;

[0054] Figure 3 is the flowchart of the online calibration method for the phase error of the control loop of the hemispherical resonator gyroscope. DETAILED DESCRIPTION

[0055] The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor fall within the scope of protection of the present application.

[0056] 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.

[0057] DETAILED DESCRIPTION Figure 2 and Figure 3To illustrate the embodiment, the control loop phase error online calibration method of the hemispherical resonator gyro in the embodiment is described. The control loop phase error of the hemispherical resonator gyro is generated by the phase difference between the X channel or Y channel amplified detection signal output by the detection electrode of the hemispherical resonator gyro and the corresponding channel detection signal before amplification at the resonant frequency ω of the resonator after the detection signal is amplified by the pre-buffer amplifier circuit in the matched control circuit connected with the hemispherical resonator gyro. The control loop phase error online calibration method comprises the following steps:

[0058] Step 1: generating high-frequency sine and cosine reference signals by a high-frequency signal generation module, generating high-frequency control signals of the excitation electrodes of the X channel and Y channel of the hemispherical resonator gyro according to the high-frequency sine and cosine reference signals and the amplitudes of the four given high-frequency signals, driving and controlling the excitation electrodes of the X channel and Y channel respectively, and making the hemispherical resonator gyro in a stable working state; at this time, the pre-buffer amplifier circuit in the matched control circuit connected with the hemispherical resonator gyro amplifies the detection signals output by the detection electrodes of the X channel and Y channel of the hemispherical resonator gyro;

[0059] wherein the high-frequency sine and cosine reference signals have the same frequency, and both are ω h , ω h >> ω, and ω is the resonant frequency of the resonator;

[0060] Step 2: high-frequency demodulating the X channel and Y channel amplified detection signals output by the pre-buffer amplifier circuit in the matched control circuit connected with the hemispherical resonator gyro by using the generated high-frequency sine and cosine reference signals, thereby obtaining the high-frequency component sine and cosine signals in the X channel amplified detection signal and the high-frequency component sine and cosine signals in the Y channel amplified detection signal;

[0061] Step 3: k-th round identification, the initial value of k is 1, the initial value of the control loop phase error is set to 0, the amplitudes of the four given high-frequency signals are taken as the observation quantity, the high-frequency component sine and cosine signals demodulated from the X channel and Y channel amplified detection signals are taken as the expected output quantity, and the phase error identification algorithm is used to realize the online identification of the control loop phase error;

[0062] Step 4: judging whether the difference between the phase errors obtained by the adjacent two rounds of identification is less than a set threshold value, and if the result is yes, jumping to step 5, otherwise, k=k+1, and jumping to step 3;

[0063] Step 5: taking the phase error obtained by the k-th round of identification as the target phase-locked phase of the phase-locked loop in the matched control circuit connected with the hemispherical resonator gyro, thereby realizing the online calibration of the control loop phase error of the hemispherical resonator gyro.

[0064] In a specific application, when the difference between the phase errors obtained by the adjacent two wheels is less than a set threshold, it is proved that the phase error obtained by the current round of recognition converges, at which time the phase error obtained by the current round of recognition is taken as the real control loop phase error, that is, the phase difference between the detection signal amplified by the X channel or Y channel of the pre-buffer amplification circuit and the detection signal before being amplified by the corresponding channel at the resonant frequency ω of the resonator

[0065] Further, as a preferred mode, the stable working state in step 1 is that the amplitude of the resonator of the hemispherical resonator gyroscope remains constant, and the resonator quadrature wave is zero.

[0066] Further, as a preferred mode, the implementation mode of generating the high-frequency control signals of the drive electrodes of the X channel and Y channel of the hemispherical resonator gyroscope in step 1 is:

[0067]

[0068] wherein V x1 and V y1 are the high-frequency control signals of the drive electrodes of the X channel and Y channel, V x and V y are the original control signals of the drive electrodes of the X channel and Y channel, U xc , U xs , U yc and U yc are the amplitudes of the first to fourth given high-frequency signals, V hs and V hc are high-frequency sine and cosine reference signals, respectively.

[0069] Further, the amplified detection signals of the X channel and Y channel output by the pre-buffer amplification circuit are:

[0070]

[0071] The high-frequency components x′ h and y′ h in the amplified detection signals x h and y h of the X channel and Y channel are:

[0072]

[0073] wherein x h and y hX and Y channel amplified detection signals output by the pre-buffering amplification circuit, respectively, a represents the amplitude of the main standing wave, q represents the amplitude of the quadrature wave, K is the detection gain, t is the time, θ is the azimuth angle of the standing wave, x hc is the high-frequency cosine component of the detection signal output by the X channel of the hemispherical resonator gyroscope, x hs is the high-frequency sine component of the detection signal output by the X channel of the hemispherical resonator gyroscope, y hs is the high-frequency sine component of the detection signal output by the Y channel of the hemispherical resonator gyroscope, y hc is the high-frequency cosine component of the detection signal output by the Y channel of the hemispherical resonator gyroscope, is the phase error of the control loop, is the phase difference between the X channel or Y channel amplified detection signal output by the pre-buffering amplification circuit and the detection signal before amplification in the corresponding channel at frequency ω h .

[0074] Furthermore, the implementation of the high-frequency components of the X channel amplified detection signal, the high-frequency component cosine signal and the high-frequency component cosine signal of the Y channel amplified detection signal demodulated in step 2 is as follows:

[0075]

[0076] In the above formula, LPF(·) is a low-pass filter, V hs and V hc are high-frequency sine and cosine reference signals, respectively, K is the detection gain, is the phase difference between the X channel or Y channel amplified detection signal output by the pre-buffering amplification circuit and the detection signal before amplification in the corresponding channel at frequency ω h , C hx is the high-frequency component cosine signal of the X channel amplified detection signal demodulated, C hy is the high-frequency component cosine signal of the Y channel amplified detection signal demodulated, S hx is the high-frequency component sine signal of the X channel amplified detection signal demodulated, S hy is the high-frequency component sine signal of the Y channel amplified detection signal demodulated; x hc is the high-frequency cosine component of the detection signal output by the X channel of the hemispherical resonator gyroscope, x hs is the high-frequency sine component of the detection signal output by the X channel of the hemispherical resonator gyroscope, y hs is the high-frequency sine component of the detection signal output by the Y channel of the hemispherical resonator gyroscope, y hc is the high-frequency cosine component of the detection signal output by the Y channel of the hemispherical resonator gyroscope.

[0077] Further, refer to Figure 2 The specific process of realizing the online identification of the phase error of the control loop in step 3 by using the phase error identification algorithm is as follows:

[0078] Step 30, solving the transformation matrix D according to the relative relationship of x hs , y hs , x hc , y hc and S hx , S hy , C hx , C hy , specifically as follows:

[0079]

[0080] wherein, is the phase difference between the amplified detection signal of the X channel or the Y channel output by the pre-buffering amplification circuit and the detection signal before amplification of the corresponding channel at the frequency ω h ; C hx is the high-frequency component cosine signal in the amplified detection signal of the X channel demodulated by the high-frequency demodulation, C hy is the high-frequency component cosine signal in the amplified detection signal of the Y channel demodulated by the high-frequency demodulation, S hx is the high-frequency component sine signal in the amplified detection signal of the X channel demodulated by the high-frequency demodulation, S hy is the high-frequency component sine signal in the amplified detection signal of the Y channel demodulated by the high-frequency demodulation; x hc is the high-frequency cosine component of the detection signal output by the X channel of the hemispherical resonator, x hs is the high-frequency sine component of the detection signal output by the X channel of the hemispherical resonator, y hs is the high-frequency sine component of the detection signal output by the Y channel of the hemispherical resonator, y hc is the high-frequency cosine component of the detection signal output by the Y channel of the hemispherical resonator;

[0081] Step 31, establishing a correlation model according to the amplitudes of the four given high-frequency signals as observation quantities and the high-frequency component sine and cosine signals in the amplified detection signals of the X channel and the Y channel demodulated by the high-frequency demodulation as expected output quantities:

[0082]

[0083] wherein, U xc , U xs , U yc and U yc are the amplitudes of the first to fourth given high-frequency signals, κ is the control gain, and K is the detection gain;

[0084] Step 32, convert the correlation model into a discrete product form: C(k) = U(k)β(k);

[0085] wherein,

[0086]

[0087]

[0088]

[0089] wherein, C(k) is an expected output vector at the kth sampling time, U(k) is an observation vector at the kth sampling time, β(k) is a parameter vector at the kth sampling time, k is a sampling time sequence number, k = 1, 2, 3, …, C(k) = U(k)β(k) is a correlation model of the expected output vector C(k) and the observation vector U(k) at the kth sampling time, and k = 1, 2, 3, …. hx (k) is a high-frequency component cosine signal in the X channel amplified detection signal demodulated at the kth sampling time, C(k) = U(k)β(k) is a correlation model of the expected output vector C(k) and the observation vector U(k) at the kth sampling time, and k = 1, 2, 3, …. hy (k) is a high-frequency component cosine signal in the Y channel amplified detection signal demodulated at the kth sampling time, S(k) = U(k)β(k) is a correlation model of the expected output vector S(k) and the observation vector U(k) at the kth sampling time, and k = 1, 2, 3, …. hx (k) is a high-frequency component sine signal in the X channel amplified detection signal demodulated at the kth sampling time, S(k) = U(k)β(k) is a correlation model of the expected output vector S(k) and the observation vector U(k) at the kth sampling time, and k = 1, 2, 3, …. hy (k) is a high-frequency component sine signal in the Y channel amplified detection signal demodulated at the kth sampling time, S(k) = U(k)β(k) is a correlation model of the expected output vector S(k) and the observation vector U(k) at the kth sampling time, and k = 1, 2, 3, …. xc (k) is a high-frequency component cosine signal in the X channel amplified detection signal demodulated at the kth sampling time, S(k) = U(k)β(k) is a correlation model of the expected output vector S(k) and the observation vector U(k) at the kth sampling time, and k = 1, 2, 3, …. xs (k) is a high-frequency component cosine signal in the Y channel amplified detection signal demodulated at the kth sampling time, S(k) = U(k)β(k) is a correlation model of the expected output vector S(k) and the observation vector U(k) at the kth sampling time, and k = 1, 2, 3, …. yc (k) is a high-frequency component cosine signal in the X channel amplified detection signal demodulated at the kth sampling time, S(k) = U(k)β(k) is a correlation model of the expected output vector S(k) and the observation vector U(k) at the kth sampling time, and k = 1, 2, 3, …. yc (k) is a high-frequency component cosine signal in the Y channel amplified detection signal demodulated at the kth sampling time, S(k) = U(k)β(k) is a correlation model of the expected output vector S(k) and the observation vector U(k) at the kth sampling time, and k = 1, 2, 3, ….

[0090] Step 33, according to U(k) in step 32, the gain vector H(k) and the covariance matrix P(k) of the phase error identification algorithm corresponding to the kth sampling time are obtained.

[0091]

[0092]

[0093] 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; when the forgetting factor is small, the algorithm converges fast, but the steady state is easily affected by noise; on the contrary, the larger the forgetting factor, the slower the algorithm converges, but the steady state is not easily disturbed by noise.

[0094] Step 34, according to C(k) and U(k) obtained in step 32, and H(k) obtained in step 33, the parameter vector β(k) of the kth sampling time is obtained;

[0095] β(k) = β(k-1) + H(k)(C(k)-U(k)β(k-1));

[0096] wherein β(k-1) is the parameter vector of the (k-1)th sampling time,

[0097] Step 35, according to β(k) obtains

[0098]

[0099] wherein, β1(k) is the element of the first row and the first column of β(k), and β2(k) is the element of the second row and the first column of β(k);

[0100] Step 36, according to and ω h the control loop phase error is obtained,

[0101] Principle analysis: the present application eliminates the influence of the phase difference between the detection signal amplified by the X channel or Y channel of the pre-buffer amplification circuit and the detection signal before being amplified by the corresponding channel at the resonant frequency ω of the resonator on the gyro drift without relying on external equipment. The present application superimposes a given high-frequency signal in the resonator control signal, and then demodulates the detection signal by using the high-frequency reference signal to extract the sine and cosine components of the resonator high-frequency signal. Finally, the phase error of the control loop is obtained by using the online identification algorithm according to the high-frequency control signal and the high-frequency demodulation result, and the target phase-locked phase of the phase-locked loop is adjusted in real time according to the identification result to eliminate the influence of the phase error on the gyro drift. The present application can be applied to the online calibration of the control loop phase error of the hemispherical resonator gyro.

[0102] 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 phase error of control loop of hemispherical resonator gyro, characterized in that, The online calibration method comprises: Step 1, generating high-frequency cosine reference signals by a high-frequency signal generation module, generating high-frequency control signals of the excitation electrodes of the X channel and the Y channel of the hemispherical resonator gyro according to the high-frequency cosine reference signals and the amplitudes of the four given high-frequency signals, driving and controlling the excitation electrodes of the X channel and the Y channel respectively, so that the hemispherical resonator gyro is in a stable working state; at this time, the pre-buffer amplification circuit in the matched control circuit connected with the hemispherical resonator gyro amplifies the detection signals output by the detection electrodes of the X channel and the Y channel of the hemispherical resonator gyro; The high-frequency cosine reference signal has the same frequency as the high-frequency sine reference signal. , , is the resonance frequency of the harmonic oscillator; the amplitudes of the four given high-frequency signals are different from each other. Step 2, using the generated high-frequency cosine reference signals to high-frequency demodulate the X channel and Y channel amplified detection signals output by the pre-buffer amplification circuit in the matched control circuit connected with the hemispherical resonator gyro, so as to obtain the high-frequency component cosine signals in the X channel amplified detection signals and the high-frequency component cosine signals in the Y channel amplified detection signals; Step 3, the Wheel identification, The initial value is 1, and the initial value of the control loop phase error is set to 0. The amplitudes of four given high-frequency signals are used as the observations, and the high-frequency sine and cosine signals in the amplified detection signals of the X and Y channels after high-frequency demodulation are used as the desired outputs. The phase error identification algorithm is used to realize the online identification of the control loop phase error, specifically including: Step 30, according to , , , and , , , solving the transformation matrix from the relative relationship , the specific process includes: ； wherein, a phase difference between the detection signal amplified by the X channel or the Y channel of the pre-buffering amplification circuit and the detection signal before being amplified by the corresponding channel of the pre-buffering amplification circuit at a frequency ; a high-frequency component cosine signal in the detection signal amplified by the X channel of the high-frequency demodulation circuit, a high-frequency component cosine signal in the detection signal amplified by the Y channel of the high-frequency demodulation circuit, a high-frequency component sine signal in the detection signal amplified by the X channel of the high-frequency demodulation circuit, a high-frequency component sine signal in the detection signal amplified by the Y channel of the high-frequency demodulation circuit; a high-frequency cosine component of the detection signal output by the X channel of the hemispherical resonator gyroscope, a high-frequency sine component of the detection signal output by the X channel of the hemispherical resonator gyroscope, a high-frequency sine component of the detection signal output by the Y channel of the hemispherical resonator gyroscope, a high-frequency cosine component of the detection signal output by the Y channel of the hemispherical resonator gyroscope; Step 31, establishing a correlation model according to the amplitudes of the four given high-frequency signals as observation quantities and the high-frequency demodulated high-frequency component cosine signals in the X channel and Y channel amplified detection signals as expected output quantities: ； wherein , , and are the amplitudes of the first to fourth given high-frequency signals, is the control gain, is the detection gain; Step 32, converting the association model into a discrete product form: ; Wherein, ； ； ； in, For the first The expected output vector at each sampling time point, For the first The observation vector at the nth sampling time, β(k) is the nth sampling time. The parameter vector at each sampling time point This is the sampling time sequence number. , For the first The high-frequency cosine signal in the X-channel amplified detection signal corresponding to each sampling time. For the first The high-frequency cosine signal in the Y-channel amplified detection signal corresponding to each sampling time. For the first The high-frequency sinusoidal signal in the X-channel amplified detection signal corresponding to each sampling time. For the first The high-frequency component sinusoidal signal of the amplified detection signal output from the Y channel at each sampling time point after high-frequency demodulation; , , and The first The amplitudes of the first to fourth given high-frequency signals corresponding to each sampling time; Step 33, according to step 32 , the gain vector and the covariance matrix of the phase error identification algorithm corresponding to the first sampling moment are calculated; Step 34, from the result of step 32 and , and the result of step 33 , the parameter vector of the first sampling time is calculated ; Step 35, according to obtained ; ； wherein , is the element of the first row and first column of the matrix is the element of the second row and first column of the matrix Step 36, according to and obtaining a control loop phase error, ; Step 4, judging whether the difference between the phase errors obtained by the adjacent two rounds is less than a set threshold, and the result is yes, then jumping to step 5, otherwise, jumping to step 3; , jumping to step 3; Step 5, place the first The phase error obtained by wheel identification is used as the target phase-locked phase in the phase-locked loop of the matching control circuit without virtual precession control connected to the hemispherical resonant gyroscope, thereby realizing online calibration of the phase error of the control loop of the hemispherical resonant gyroscope.

2. The method according to claim 1, wherein the method is characterized by: The stable working state in step 1 is that the resonator amplitude of the hemispherical resonator gyro remains constant, and the resonator orthogonal wave is zero.

3. The method according to claim 1, wherein the method is characterized by: The implementation mode of generating the high-frequency control signals of the excitation electrodes of the X channel and the Y channel of the hemispherical resonator gyro in step 1 is: ； wherein and are high frequency control signals for the excitation electrodes of the X- and Y-channels, respectively, and are original control signals for the excitation electrodes of the X- and Y-channels, respectively, , , and are amplitudes of the first to fourth given high frequency signals, respectively, and are high frequency sine and cosine reference signals, respectively.

4. The method according to claim 1, wherein the method is characterized by: The X channel and Y channel amplified detection signals output by the pre-buffer amplification circuit are respectively: ； wherein, and are the amplified detection signals of the X channel and the Y channel outputted by the pre-buffering amplification circuit respectively, represents the amplitude of the main standing wave, represents the amplitude of the quadrature wave, is the detection gain, t is time, and θ is the azimuth angle of the standing wave, is the high-frequency cosine component of the detection signal outputted by the X channel of the hemispherical resonator gyroscope, is the high-frequency sine component of the detection signal outputted by the X channel of the hemispherical resonator gyroscope, is the high-frequency sine component of the detection signal outputted by the Y channel of the hemispherical resonator gyroscope, is the high-frequency cosine component of the detection signal outputted by the Y channel of the hemispherical resonator gyroscope, is the phase error of the control loop, is the phase difference between the amplified detection signal of the X channel or the Y channel outputted by the pre-buffering amplification circuit and the detection signal before amplification of the corresponding channel at the frequency .

5. The method of claim 1, wherein the method is used for on-line calibration of phase error of control loop of hemispherical resonator gyroscopes. The implementation mode of the high-frequency demodulated high-frequency component cosine signals in the X channel amplified detection signals and the high-frequency component cosine signals in the Y channel amplified detection signals in step 2 is: ； In the above formula, is a low-pass filtering operation, and are high-frequency sine and cosine reference signals, respectively, is a detection gain, is a phase difference between the X-channel or Y-channel amplified detection signal output by the pre-buffering amplification circuit and the detection signal before amplification in the corresponding channel at a frequency , is a high-frequency component cosine signal in the X-channel amplified detection signal demodulated at high frequency, is a high-frequency component cosine signal in the Y-channel amplified detection signal demodulated at high frequency, is a high-frequency component sine signal in the X-channel amplified detection signal demodulated at high frequency, is a high-frequency component sine signal in the Y-channel amplified detection signal demodulated at high frequency; is a high-frequency cosine component of the detection signal output by the X-channel of the hemispherical resonator gyroscope, is a high-frequency sine component of the detection signal output by the X-channel of the hemispherical resonator gyroscope, is a high-frequency sine component of the detection signal output by the Y-channel of the hemispherical resonator gyroscope, is a high-frequency cosine component of the detection signal output by the Y-channel of the hemispherical resonator gyroscope.

6. The method according to claim 1, wherein In step 33, ； ； wherein , is the identity matrix, is a forgetting factor, is chosen in the range (0, 1], is the covariance matrix corresponding to the th sampling instant.

7. The method according to claim 1, wherein In step 34, ; wherein is the parameter vector at the th sampling instant, .

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