A method and device for controlling different frequencies of a hemispherical resonator gyro

Abstract

The application discloses a kind of hemispherical resonator gyro different frequency control method and device, method includes the following steps: change the mode azimuth of hemispherical resonator gyro, for each mode azimuth, real-time acquisition phase-locked frequency, according to all mode azimuth and its corresponding phase-locked frequency, construct about phase-locked frequency and mode azimuth relationship model, solve the relationship model, obtain frequency division control parameter;According to frequency division control parameter and real-time acquisition phase-locked frequency calculation Y phase-locked frequency, according to the Y phase-locked frequency calculated Y electrode drive signal, according to real-time acquisition phase-locked frequency calculation X electrode drive signal, to realize the frequency division control of drive signal when hemispherical resonator gyro normal work.This application can reduce the influence of hemispherical resonator gyro frequency difference, improve angle sensitive precision.

Description

Technical Field

[0001] This invention relates to the field of inertial technology, specifically to a method and device for controlling different frequencies of a hemispherical resonant gyroscope. Background Technology

[0002] A hemispherical resonator gyroscope is an inertial sensing device with advantages such as small size, light weight, simple structure, and long lifespan. It detects angular velocity by utilizing the standing wave vibration of a hemispherical resonator. A sinusoidal electrostatic force is applied to the edge of the resonator using an electrostatic, electromagnetic, or piezoelectric exciter, causing it to vibrate at its natural frequency.

[0003] Due to factors such as structural errors of the resonator, inconsistent material properties, and deviations in assembly processes, gyroscopes can develop frequency differences. Typically, the Lynch model is used in hemispherical control circuits. In the Lynch model, the X and Y frequencies are assumed to be the same. However, in actual use, due to frequency differences, the X and Y frequencies cannot be the same. These frequency differences can cause the gyroscope to drift orthogonally, affecting the angle sensitivity accuracy. Summary of the Invention

[0004] To address the problems in the background technology, this invention proposes a method for controlling different frequencies of a hemispherical resonant gyroscope, so as to reduce the influence of frequency difference of the hemispherical resonant gyroscope and improve the angle sensitivity accuracy.

[0005] The present invention adopts the following technical solution: A method for controlling different frequencies of a hemispherical resonant gyroscope includes the following steps: The mode shape azimuth angle of the hemispherical resonant gyroscope is changed. For each mode shape azimuth angle, the phase-locked frequency is collected in real time. Based on all mode shape azimuth angles and their corresponding phase-locked frequencies, a relationship model between the phase-locked frequency and the mode shape azimuth angle is constructed. The relationship model is solved to obtain the frequency division control parameters. The Y-phase-locked frequency is calculated based on the frequency division control parameters and the real-time acquired phase-locked frequency. Based on the calculated Y phase-locked frequency The Y-electrode drive signal is calculated, and the X-electrode drive signal is calculated based on the real-time acquired phase-locked frequency, so as to realize the frequency division control of the drive signal when the hemispherical resonant gyroscope is working normally.

[0006] In the aforementioned method for controlling different frequencies of a hemispherical resonant gyroscope, preferably, the relationship model between the phase-locked frequency and the mode shape azimuth angle is as follows: , in For phase-locked frequency, denoted as mode shape azimuth, and K1, K2, and b are frequency division control parameters.

[0007] The aforementioned method for controlling the different frequencies of a hemispherical resonant gyroscope preferably involves calculating the Y-phase-locked frequency based on the frequency division control parameters. Specifically, it includes: .

[0008] In the aforementioned method for controlling the different frequencies of a hemispherical resonant gyroscope, preferably, the calculation models for the X-electrode driving signal and the Y-electrode driving signal are as follows: , , in, This is the X-electrode driving signal. This is the driving signal for the Y electrode. For amplitude control, For orthogonal control forces, The initial phase of the reference signal.

[0009] The above-mentioned method for controlling the different frequencies of a hemispherical resonant gyroscope preferably involves changing the mode shape azimuth angle of the hemispherical resonant gyroscope. Specifically, this includes placing the hemispherical resonant gyroscope on a turntable and rotating it at a rate of 5° / s-25° / s to change the mode shape azimuth angle of the hemispherical resonant gyroscope.

[0010] As a general inventive concept, the present invention also provides an apparatus for implementing the above-described method for controlling different frequencies of a hemispherical resonant gyroscope, comprising: The execution module is used to change the mode shape azimuth angle of the hemispherical resonant gyroscope, and the acquisition module is used to acquire the phase-locked frequency in real time and send it to the host computer. The host computer is used to construct a relationship model between the phase-locked frequency and the mode shape azimuth angle based on all mode shape azimuth angles and their corresponding phase-locked frequencies, solve the relationship model to obtain the frequency division control parameters, and send them to the control chip. The control chip is used to calculate the Y-phase-locked frequency based on the frequency division control parameters and the phase-locked frequency acquired in real time by the acquisition module. Based on the calculated Y phase-locked frequency The Y-electrode drive signal is calculated, and the X-electrode drive signal is calculated based on the phase-locked frequency acquired in real time by the acquisition module, so as to realize the frequency division control of the drive signal when the hemispherical resonant gyroscope is working normally.

[0011] Preferably, in the aforementioned device, the relationship model between the phase-locked frequency and the mode shape azimuth angle is specifically as follows: , in For phase-locked frequency, denoted as mode shape azimuth, and K1, K2, and b are frequency division control parameters.

[0012] Preferably, the Y-phase-locked frequency of the above-described device is calculated based on the frequency division control parameters. Specifically, it includes: .

[0013] In the aforementioned apparatus, preferably, the calculation models for the X-electrode driving signal and the Y-electrode driving signal are as follows: , , in, This is the X-electrode driving signal. This is the driving signal for the Y electrode. For amplitude control, For orthogonal control forces, The initial phase of the reference signal.

[0014] Preferably, in the above-described device, the execution module is a turntable, which changes the mode azimuth angle of the hemispherical resonant gyroscope. Specifically, this includes placing the hemispherical resonant gyroscope on the turntable and rotating it at a rate of 5° / s-25° / s to change the mode azimuth angle of the hemispherical resonant gyroscope.

[0015] Compared with the prior art, the advantages of the present invention are as follows: The hemispherical resonant gyroscope non-frequency control method of the present invention obtains frequency division control parameters by fitting based on the phase-locked frequency of the X electrode and the mode shape azimuth angle. Then, according to the phase difference relationship between the driving electrodes X and Y, the relationship between the phase-locked frequency of the Y electrode and the phase-locked frequency of the X electrode is obtained. Thus, when the hemispherical resonant gyroscope is working normally, the X electrode driving signal is calculated based on the real-time acquired phase-locked frequency, and the Y phase-locked frequency is calculated based on the frequency division control parameters and the real-time acquired phase-locked frequency. Based on the calculated Y phase-locked frequency The Y-electrode driving signal is calculated, and the influence of frequency difference is suppressed by different frequency control methods, thereby improving the angle sensitivity accuracy. Attached Figure Description

[0016] To facilitate understanding of the invention, it will be described in more detail with reference to the specific embodiments shown in the accompanying drawings. These drawings depict only typical embodiments of the invention and should not be considered as limiting the scope of protection of the invention.

[0017] Figure 1 This is a fitted curve of the relative mode shape angle change of the harmonic oscillator after removing the temperature effect, under the condition of an external angular velocity input of 10° / s in an embodiment of the present invention.

[0018] Figure 2 The curves showing the change of the phase-locked frequency of the driving electrode X and the actual phase-locked frequency of the driving electrode Y over time are shown in the embodiments of the present invention.

[0019] Figure 3The orthogonal error versus time curve for enabling different frequency control functions in this invention example.

[0020] Figure 4 The graph shows the orthogonal error versus time curves for conventional methods using the same frequency control. Detailed Implementation

[0021] The embodiments of the present invention are described below with reference to the accompanying drawings to enable those skilled in the art to better understand and implement the present invention. However, the listed embodiments are not intended to limit the present invention. In the absence of conflict, the following embodiments and the technical features in the embodiments can be combined with each other, wherein the same components are indicated by the same reference numerals.

[0022] like Figures 1-4 As shown in the figure, this embodiment proposes a method for controlling different frequencies of a hemispherical resonant gyroscope, including the following steps: The mode shape azimuth angle of the hemispherical resonant gyroscope is changed. For each mode shape azimuth angle, the phase-locked frequency is collected in real time. Based on all mode shape azimuth angles and their corresponding phase-locked frequencies, a relationship model between the phase-locked frequency and the mode shape azimuth angle is constructed. The relationship model is solved to obtain the frequency division control parameters. The Y-phase-locked frequency is calculated based on the frequency division control parameters and the real-time acquired phase-locked frequency. Based on the calculated Y phase-locked frequency The Y-electrode drive signal is calculated, and the X-electrode drive signal is calculated based on the real-time acquired phase-locked frequency, so as to realize the frequency division control of the drive signal when the hemispherical resonant gyroscope is working normally.

[0023] Specifically, the relationship model between the phase-locked frequency and the mode shape azimuth angle is as follows: , in For phase-locked frequency, denoted as mode shape azimuth, and K1, K2, and b are frequency division control parameters.

[0024] Specifically, the Y-phase-locked frequency is calculated based on the frequency division control parameters. Specifically, it includes: .

[0025] The calculation models for the X-electrode driving signal and the Y-electrode driving signal are as follows: , , in, This is the X-electrode driving signal. This is the driving signal for the Y electrode. For amplitude control, For orthogonal control forces, The initial phase of the reference signal.

[0026] Changing the mode azimuth angle of a hemispherical resonant gyroscope specifically involves placing the hemispherical resonant gyroscope on a turntable and rotating it at a rate of 5° / s-25° / s to change the mode azimuth angle of the hemispherical resonant gyroscope.

[0027] The following is a detailed description of the hemispherical gyroscope frequency control method of the present invention: For an 8-electrode hemispherical resonant gyroscope, with each electrode 45° out of phase, the vibration displacement equations for the X and Y electrodes in the Lynch model, if the frequency difference is not ignored, are as follows: , , in, The azimuth angle of the vibration mode. X is the phase-locked frequency. For the Y-phase-locked frequency, The main wave phase variable, The amplitude of the main standing wave. The amplitude of the standing wave orthogonal wave.

[0028] Select a reference signal with the same frequency as X-locked loop: , Select a reference signal with the same frequency as the Y-locked loop: , Where A is the amplitude of the reference signal. The initial phase of the reference signal.

[0029] The displacement equation of the X-detector electrode is multiplied and demodulated with its reference signal: , , The displacement equation of the Y-detector electrode is multiplied and demodulated with its reference signal: , , right , , and After simplification, we get: ; ; ; ; right , , and After low-pass filtering, we get: ; ; ; ; Therefore, it can be concluded that the demodulation of the X and Y detection signals in the Lynch model, and the different frequency controls... , , and Low-pass filtering and same-frequency control , , and The reason for this consistency is that the low-pass filter demodulates the high-frequency frequencies. and It has been filtered out. It is clear that different frequency control has no effect on the Lynch model demodulation, and frequency division demodulation is unnecessary for the X and Y detection signals. This also indicates that whether or not frequency division is used, it will not affect the calculation of the mode shape azimuth angle, or the subsequent calculation of intermediate quantities such as gain error, skew angle error, and phase error, thus not introducing new errors into the calculation of the driving electrodes.

[0030] Next, we analyze the impact of different frequency control on the driving electrodes X and Y. The driving electrode model with different frequency control is as follows: , , in, The driving signal for the driving electrode X. For driving the Y electrode, X is the phase-locked frequency. For the Y-phase-locked frequency, For amplitude control, For orthogonal control forces, The azimuth angle of the vibration mode. The initial phase is the reference signal. It is clear that the X and Y driving forces calculated by same-frequency control and frequency-division control are different.

[0031] Phase-locked frequency in the Lynch model The frequency obtained through the PI phase-locked electrode X is therefore the frequency in the above formula. Phase-locked frequency obtained by PI phase-locking In the calculation, during external rotation, the harmonic oscillator mode shape rotates relative to the base, allowing for fitting of the data. Relationship with mode shape azimuth. A hemispherical resonant gyroscope is placed on a turntable, which is then set to rotate at a predetermined rate. After the mode shape has rotated one revolution, the X-phase-locked frequency is fitted using the least squares method. Curves, such as Figure 1 As shown. X phase-locked frequency The formula for fitting the curve can be written as: , Where K1, K2, and b are frequency division control parameters; specifically, K1 is the coefficient of the fitted sine term, K2 is the coefficient of the fitted cosine term, and b is the bias parameter. It represents the azimuth angle of the vibration mode.

[0032] According to the auxiliary angle formula Simplifying, we get: , For an 8-electrode hemispherical resonator gyroscope, the driving electrode X and the driving electrode Y are 45° out of phase, therefore The calculation formula is: , The coefficients K1 and K2 are obtained by least squares fitting. The host computer transmits the coefficients K1 and K2 to the control chip, and the control chip uses the X phase-locked frequency obtained from the PI phase-locking method. Substitute into the above formula to calculate the Y-phase lock frequency of the driving electrode. Then, based on the X phase-locked frequency... and Y-phase-locked frequency By calculating the driving signals of the X driving electrode and the Y driving electrode, different frequency control of the driving signals can be achieved.

[0033] The following are specific examples of the hemispherical resonant gyroscope frequency control method of the present invention: S01. Fix the hemispherical gyroscope on the single-axis turntable, turn on the phase-locked loop, quadrature, and amplitude closed-loop control functions, and wait until the phase-locked frequency no longer drifts.

[0034] S02. Set the turntable speed to 10° / s and record the mode shape angle and phase-locked frequency. The test will stop after the upper computer rotates the vibration mode angle once.

[0035] S03. Use least squares fitting to obtain the phase-locked frequency. And mode angle curves, such as Figure 1 As shown, the sine coefficient K1 and cosine coefficient K2 are obtained: And store it in the control chip. Calculate Curve, view Actual phase-locked frequency, such as Figure 2 As shown.

[0036] S04. Enable frequency division control function and record the quadrature control error curve, such as... Figure 3 As shown. Turn off the frequency division control function and record the quadrature control error curve, as shown. Figure 4 As shown. By Figure 3 and Figure 4 The comparison shows that the error is significantly smaller when the frequency division control function is enabled and the quadrature is canceled, indicating that the different frequency control suppresses the influence of frequency difference and improves the control accuracy.

[0037] The embodiments described above are merely preferred embodiments of the present invention. The terms "in one embodiment," "in another embodiment," "in yet another embodiment," or "in still another embodiment" used in this specification all refer to one or more of the same or different embodiments according to this disclosure. Ordinary variations and substitutions made by those skilled in the art within the scope of the present invention should be included within the protection scope of the present invention.

Claims

1. A method for controlling different frequencies of a hemispherical resonant gyroscope, characterized in that, Includes the following steps: The mode shape azimuth angle of the hemispherical resonant gyroscope is changed. For each mode shape azimuth angle, the phase-locked frequency is collected in real time. Based on all mode shape azimuth angles and their corresponding phase-locked frequencies, a relationship model between the phase-locked frequency and the mode shape azimuth angle is constructed. The relationship model is solved to obtain the frequency division control parameters. The Y-phase-locked frequency is calculated based on the frequency division control parameters and the real-time acquired phase-locked frequency. Based on the calculated Y phase-locked frequency The Y-electrode drive signal is calculated, and the X-electrode drive signal is calculated based on the real-time acquired phase-locked frequency, so as to realize the frequency division control of the drive signal when the hemispherical resonant gyroscope is working normally. The specific model relating the phase-locked frequency and the mode shape azimuth angle is as follows: ， in For phase-locked frequency, The mode shape azimuth is K1, K2 and b are frequency division control parameters; Calculate the Y-locked frequency based on the frequency division control parameters. Specifically, it includes: 。 2. The method for controlling different frequencies of a hemispherical resonant gyroscope according to claim 1, characterized in that, The calculation models for the X-electrode driving signal and the Y-electrode driving signal are as follows: ， ， in, This is the X-electrode driving signal. This is the driving signal for the Y electrode. For amplitude control, For orthogonal control forces, The initial phase of the reference signal.

3. The method for controlling different frequencies of a hemispherical resonant gyroscope according to any one of claims 1-2, characterized in that, Changing the mode azimuth angle of a hemispherical resonant gyroscope specifically involves placing the hemispherical resonant gyroscope on a turntable and rotating it at a rate of 5° / s-25° / s to change the mode azimuth angle of the hemispherical resonant gyroscope.

4. An apparatus for implementing the hemispherical resonant gyroscope different frequency control method as described in claim 1, characterized in that, include: The execution module is used to change the mode azimuth angle of the hemispherical resonant gyroscope. The acquisition module is used to acquire the phase-locked loop frequency in real time and send it to the host computer. The host computer is used to construct a relationship model between the phase-locked frequency and the mode shape azimuth angle based on all mode shape azimuth angles and their corresponding phase-locked frequencies, solve the relationship model to obtain the frequency division control parameters, and send them to the control chip. The control chip is used to calculate the Y-phase-locked frequency based on the frequency division control parameters and the phase-locked frequency acquired in real time by the acquisition module. Based on the calculated Y phase-locked frequency The Y-electrode drive signal is calculated, and the X-electrode drive signal is calculated based on the phase-locked frequency acquired in real time by the acquisition module, so as to realize the frequency division control of the drive signal when the hemispherical resonant gyroscope is working normally. The specific model relating the phase-locked frequency and the mode shape azimuth angle is as follows: ， in For phase-locked frequency, The mode shape azimuth is K1, K2 and b are frequency division control parameters; Calculate the Y-locked frequency based on the frequency division control parameters. Specifically, it includes: 。 5. The apparatus according to claim 4, characterized in that, The calculation models for the X-electrode driving signal and the Y-electrode driving signal are as follows: ， ， in, This is the X-electrode driving signal. This is the driving signal for the Y electrode. For amplitude control, For orthogonal control forces, The initial phase of the reference signal.

6. The apparatus according to any one of claims 4-5, characterized in that, The execution module is a turntable, which changes the mode azimuth angle of the hemispherical resonant gyroscope. Specifically, it includes placing the hemispherical resonant gyroscope on the turntable and rotating it at a rate of 5° / s-25° / s to change the mode azimuth angle of the hemispherical resonant gyroscope.

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