Hemispherical resonator gyroscope scale factor self-compensation system and method

Abstract

The invention discloses a hemispherical resonator gyroscope scale factor self-compensation system and method. An X-axis electrode and a Y-axis electrode are respectively connected with a buffer amplifier, an analog-to-digital converter and a demodulation unit through switches; one output of the demodulation unit is connected with the excitation signal demodulation unit and the scale factor compensation unit, the other output of the demodulation unit is connected with the control unit through the low-pass filtering unit, the output of the control unit is connected with the scale factor compensation unit and the two signal modulation units, and the two signal modulation units are respectively connected with an X-axis electrode and a Y-axis electrode through the digital-to-analog converter; and the output of the excitation signal generator is connected with the Y-axis signal modulation unit and the excitation signal demodulation unit. A Y-axis sine excitation signal response amplitude is extracted through an excitation signal demodulation unit, and a scale factor change relation can be obtained according to a ratio relation between the amplitude and an amplitude reference value. According to the invention, the self-compensation of the scale factor can be completed, the problem that the performance of the gyro scale factor is reduced due to temperature change and aging is solved, and the temperature stability and long-term working stability of the gyro scale factor are improved.

Description

Technical Field

[0001] The invention relates to a technical improvement of a hemispherical resonant gyroscope, in particular to a hemispherical resonant gyroscope scale factor self-compensation system and method, belonging to the technical field of gyroscopes. Background Art

[0002] The gyroscope is one of the core components of the inertial navigation system, and its function is to measure the angular motion of the carrier in the inertial space. The hemispherical resonant gyroscope is a new type of inertial navigation-grade solid gyroscope, which has the advantages of small size, low cost, long life, and high reliability. It can be widely used in aviation, aerospace, vehicles, industrial robot navigators, unmanned device attitude performance detectors and attitude real-time calibrators, stable platforms, airport security and many other fields.

[0003] The scale factor is the ratio of the change in the gyro output signal to the change in the input angular velocity, which reflects the sensitivity of the gyro output signal to the input angular velocity. The scale factor is one of the important parameters for measuring the performance of the gyro, and directly affects the measurement accuracy and stability of the gyro. The factors that affect the scale factor mainly include: Temperature change: Temperature change will cause thermal expansion and contraction of the gyro material, which in turn affects the resonant frequency and scale factor of the gyro. Aging effect: Long-term use will cause changes in the internal structure of the gyro, thereby affecting the scale factor. Processing and assembly errors: The errors that may occur during the processing and assembly of the gyro will also affect its scale factor.

[0004] The hemispherical resonant gyroscope is mainly composed of a resonator and an electrode base. During the processing and assembly of the resonator and the electrode, there are various errors such as the resonator thickness, roundness error, uneven electrode graduation, incomplete electrode area, electronic device gain mismatch, and uneven installation gap between the electrode and the resonator. As a result, the hemispherical resonant gyroscope scale factor error changes with environmental changes such as temperature and long-term aging. The offline calibration accuracy is limited, resulting in a decrease in gyroscope performance, which limits the application of hemispherical gyroscopes.

[0005] In order to ensure the measurement accuracy of the gyroscope, it is usually necessary to compensate the scale factor. The compensation methods include: temperature compensation: by monitoring the temperature change of the gyroscope, and using the fitting method to convert the temperature into frequency, and then calculate the scale factor signal; circuit gain calibration: adding a reference signal to the control circuit, and using the gain calibration method to reduce the influence of the circuit gain on the scale factor. The existing compensation method usually uses open-loop temperature compensation, that is, testing the scale factor at different temperatures before leaving the factory and compensating. This method is limited by the accuracy of the temperature model modeling of the scale factor. In the modeling of a high-precision temperature model, it is necessary to consider independent variables such as temperature spatial distribution and temperature time gradient. The model parameters are obtained through sufficient temperature experiments. The workload of modeling and experiment is large. At the same time, this method cannot compensate for the change of the gyroscope scale factor caused by aging.

[0006] Therefore, how to improve the performance of the scale factor of the hemispherical resonant gyroscope has become a technical problem that needs to be solved urgently. Summary of the invention

[0007] In view of the above-mentioned deficiencies in the prior art, an object of the present invention is to provide a method for self-compensation of the scale factor of a hemispherical resonant gyroscope. The present invention can identify changes in the scale factor and complete self-compensation of the scale factor, thereby solving the problem of degradation of the gyroscope scale factor performance caused by temperature changes and aging, and improving the temperature stability and long-term working stability of the gyroscope scale factor.

[0008] In order to achieve the above object, the technical solution adopted by the present invention is as follows:

[0009] A hemispherical resonant gyroscope scale factor self-compensation system, comprising a resonator, an electrode, a switch, a buffer amplifier, an analog-to-digital converter, a demodulation unit, a low-pass filtering unit, an excitation signal generator, a control unit, an excitation signal demodulation unit, a scale factor compensation unit, a signal modulation unit, an X-axis digital-to-analog converter and a Y-axis digital-to-analog converter; the electrode is composed of an X-axis electrode and a Y-axis electrode;

[0010] The X-axis electrode and the Y-axis electrode are respectively connected to the buffer amplifier through a switch, the output of the buffer amplifier is connected to the analog-to-digital converter, and the output of the analog-to-digital converter is connected to the demodulation unit; the demodulation unit has two outputs, one output is connected to the excitation signal demodulation unit and the scale factor compensation unit in sequence; the other output of the demodulation unit is connected to the control unit through a low-pass filter unit, the output of the control unit is connected to the scale factor compensation unit and two signal modulation units, one of the signal modulation unit outputs is connected to the X-axis electrode through the X-axis digital-to-analog converter, and the other signal modulation unit output is connected to the Y-axis electrode through the Y-axis digital-to-analog converter; the output of the excitation signal generator is connected to the signal modulation unit corresponding to the Y axis and the excitation signal demodulation unit.

[0011] A hemispherical resonant gyroscope scale factor self-compensation method is implemented based on the above-mentioned hemispherical resonant gyroscope scale factor self-compensation system, and the specific steps are as follows:

[0012] S1. The hemispherical resonant gyroscope works on the X and Y axes in a time-sharing manner, using a detection circuit composed of a buffer amplifier and an analog-to-digital converter. The X and Y axis drive circuits are independent, and the gyroscope vibration antinode is locked under the X axis frame.

[0013] S2. Record the hemispherical resonant gyroscope before leaving the factory: superimpose the preset sinusoidal excitation signal with the standing wave precession drive signal, generate a drive digital signal through the signal modulation unit, convert it into an analog signal through the Y-axis digital-to-analog converter, and then apply it to the Y-axis electrode;

[0014] S3, switch the X-axis electrode and the Y-axis electrode by a switch, so that the X-axis and the Y-axis share the detection circuit in a time-sharing manner; the vibration signal of the resonator is converted into an analog voltage signal by a buffer amplifier, converted into a digital signal by an analog-to-digital converter, and completed with coherent demodulation at the gyro frequency by a demodulation unit, and the demodulation result is divided into two paths, one of which is extracted by an excitation signal demodulation unit to extract the Y-axis sinusoidal excitation signal response amplitude Amp0 as an amplitude reference value; the other is sent to a low-pass filter to filter out the sinusoidal excitation signal and then enters the control unit for control quantity resolution; the hemispherical resonant gyro scale factor corresponding to the amplitude reference value is recorded as K0;

[0015] S4, in the working state of the gyroscope, the X-axis electrode and the Y-axis electrode are switched by the switch, so that the X-axis and the Y-axis share the detection circuit in a time-sharing manner; the vibration signal is converted into an analog voltage signal by the buffer amplifier, converted into a digital signal by the analog-to-digital converter, and completed with coherent demodulation at the gyroscope frequency by the demodulation unit. The demodulation result is divided into two paths, one of which is extracted by the excitation signal demodulation unit to extract the Y-axis sinusoidal excitation signal response amplitude Amp; the other path is sent to the low-pass filter to filter out the sinusoidal excitation signal and then enters the control unit for control amount solution to obtain the precession control amount Cp;

[0016] S5, the change of Amp relative to Amp0 is the gain change, and the scale factor changes from K0 before leaving the factory to K = (Amp0 / Amp)K0; the scale factor compensation unit adjusts the precession control amount Cp to And output, completing the automatic compensation of the scale factor;

[0017] S6. Repeat steps S4 and S5 to automatically update the scale factor according to the set period, thus completing the scale factor self-compensation.

[0018] Compared with the prior art, the present invention has the following beneficial effects:

[0019] The present invention provides a hemispherical resonant gyroscope scale factor self-compensation method. By applying a sinusoidal excitation signal to a precession control loop, extracting the response amplitude of the sinusoidal excitation signal, comparing it with a reference amplitude value, and monitoring the loop gain change in real time, the scale factor change can be identified without affecting the normal operation of the gyroscope, and the scale factor can be compensated to a factory calibration state, thereby realizing an online real-time self-compensation function of the scale factor.

[0020] The self-compensation process of the present invention automatically updates the scale factor according to the time period preset by the internal program of the gyroscope, completes the self-compensation of the scale factor, can solve the problem of gyroscope scale factor performance degradation caused by temperature change and aging, improves the temperature stability and long-term working stability of the gyroscope scale factor, and meets the needs of application scenarios that require the gyroscope to work stably for a long time. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1- Prior art hemispherical resonant gyro scale factor compensation system block diagram.

[0022] Figure 2 -Block diagram of the hemispherical resonant gyro scale factor self-compensation system of the present invention. DETAILED DESCRIPTION

[0023] The present invention is further described in detail below in conjunction with the accompanying drawings and specific embodiments.

[0024] See also Figure 2 The present invention discloses a hemispherical resonator gyroscope scale factor self-compensation system, which includes a hemispherical resonator 1, an electrode 2, a switch I 3, a switch II 4, a buffer amplifier 5, an analog-to-digital converter 6, a demodulation unit 7, a low-pass filter unit 8, an excitation signal generator 9, a control unit 10, an excitation signal demodulation unit 11, a scale factor compensation unit 12, a signal modulation unit 13, an X-axis digital-to-analog converter 14, and a Y-axis digital-to-analog converter 15. The electrode is composed of an X-axis electrode and a Y-axis electrode.

[0025] The X-axis electrode and the Y-axis electrode are connected to the buffer amplifier through switch II4 and switch I3 respectively, the output of the buffer amplifier is connected to the analog-to-digital converter, and the output of the analog-to-digital converter is connected to the demodulation unit; the demodulation unit has two outputs, one output is connected to the excitation signal demodulation unit and the scale factor compensation unit in sequence; the other output of the demodulation unit is connected to the control unit through a low-pass filter unit, and the output of the control unit is connected to the scale factor compensation unit and two signal modulation units, wherein the output of one signal modulation unit is connected to the X-axis electrode through the X-axis digital-to-analog converter, and the output of the other signal modulation unit is connected to the Y-axis electrode through the Y-axis digital-to-analog converter; the output of the excitation signal generator is connected to the signal modulation unit and the excitation signal demodulation unit corresponding to the Y axis.

[0026] The functions of the components involved in the present invention are introduced as follows:

[0027] The hemispherical resonator 1 is a core sensitive device of the hemispherical resonator gyroscope, and its material is quartz.

[0028] Electrode 2 is used to detect and drive the vibration of the hemispherical resonator, and forms a capacitor with the hemispherical resonator coated with a metal film.

[0029] Switch II4 and switch I3 are used to select the X-axis and Y-axis detection circuit channels respectively, so that the X-axis and Y-axis can share the detection circuit in a time-sharing manner.

[0030] The buffer amplifier 5 is used to extract the vibration signal on the electrode 2 and plays the role of signal conversion and isolation amplification, such as a charge amplifier.

[0031] The analog-to-digital converter 6 is used to convert the detection analog voltage signals of the X-axis and the Y-axis into digital signals.

[0032] The demodulation unit 7 demodulates the gyro signal by using a demodulation algorithm to demodulate the digital signal output by the analog-to-digital converter 6 .

[0033] The low-pass filter unit 8 filters out the sinusoidal excitation signal.

[0034] The excitation signal generator 9 generates a sinusoidal excitation signal and a cosine signal which is orthogonal to the phase of the sinusoidal excitation signal.

[0035] The control unit 10 completes the calculation of control quantities such as phase-locked loop, amplitude, orthogonality, and precession.

[0036] The excitation signal demodulation unit 11 is used to extract the response amplitude of the sinusoidal excitation signal, that is, the amplitude value of the standing wave precession sinusoidal wave signal brought by the sinusoidal excitation signal.

[0037] The scale factor compensation unit 12 performs scale factor compensation using the measured response amplitude of the sinusoidal excitation signal and the amplitude reference value calibrated before leaving the factory, and outputs the precession control amount Cp after the scale factor is compensated, which is the force balance angular velocity output.

[0038] The signal modulation unit 13 generates reference sine and cosine signals of the gyro vibration according to the phase control amount and the frequency reference calculated by the control unit, modulates and generates corresponding gyro driving signals, and outputs the signals to the X-axis DAC or the Y-axis DAC.

[0039] The X-axis D / A converter 14 converts the X-axis driving signal from a digital quantity into an analog voltage and outputs the analog voltage to the X-axis electrode.

[0040] The Y-axis digital-to-analog converter 15 converts the Y-axis driving signal from a digital quantity into an analog voltage and outputs the analog voltage to the Y-axis electrode.

[0041] The specific working process and principle of the present invention are as follows:

[0042] (1) Gyro electrode configuration structure

[0043] By comparison Figure 1 and Figure 2 It can be seen that the gyro of the present invention uses a time-sharing common detection circuit for X-axis and Y-axis electrodes, and the driving circuits for X-axis and Y-axis electrodes are independent. The gyro vibration antinode is locked to the X-axis. The gyro output is the precession control quantity Cp. This structure is different from the traditional force-balanced hemispherical gyro structure (such as the X-axis electrode detection circuit is independent, and the X-axis electrode driving circuit is also independent). Figure 1 Different from the above, the X-axis and Y-axis electrodes use a time-sharing shared detection circuit, and an excitation signal generator 9, a low-pass filter unit 8, and an excitation signal demodulation unit 11 are added to achieve self-compensation for the scale factor.

[0044] In this framework, the scale factor K of the hemispherical resonant gyroscope is inversely proportional to the product of the X-axis detection gain and the Y-axis drive gain, that is:

[0045]

[0046] The detection gains of X and Y axes are K sX and K sY , the detection gain is the product of the electrode capacitance gain and the detection circuit gain, as shown in the following formula:

[0047]

[0048] K cX and K cY are the electrode capacitance gains of the X and Y axes, respectively, and K sE is the gain of the shared detection circuit.

[0049] but:

[0050]

[0051] Since the ratio of the electrode capacitance gain of the X and Y axes of the hemispherical resonant gyroscope is very stable with changes in temperature and other environmental conditions, it can be considered that the ratio of the electrode capacitance gain of the X and Y axes is a constant β, that is:

[0052] K sX =β·K sY (4)

[0053] Then the relationship between the scale factor and the gain is converted to:

[0054]

[0055] (2) Excitation signal generator

[0056] The excitation signal generator 9 generates a sinusoidal digital signal D0 according to a preset frequency ω0:

[0057] D0=A0 sin(ω0t) (6)

[0058] Where --D0 is the sinusoidal excitation signal;

[0059] --A0 is the amplitude of the sinusoidal excitation signal;

[0060] --ω0 is the frequency of the sinusoidal excitation signal;

[0061] --t is the time.

[0062] The frequency ω0 of the sinusoidal excitation signal is set to be much higher than the bandwidth of the gyroscope and the angular motion frequency of its working environment. The response of the sinusoidal excitation signal is filtered out by the low-pass filter unit 8, so that the sinusoidal excitation signal does not affect the control loop of the gyroscope and does not interfere with the normal operation of the gyroscope. If the bandwidth of the gyroscope is 20 Hz, the sinusoidal excitation signal can be set to be much higher than the bandwidth of the gyroscope and the angular motion frequency of its working environment, for example, 1000 Hz.

[0063] The sinusoidal excitation signal is superimposed on the precession control loop and modulated by the signal modulation unit 13 to generate the corresponding gyro drive signal. In addition, the excitation signal generator will also generate a cosine wave digital signal according to the preset frequency ω0, and the sine and cosine signals are sent to the back-end excitation signal demodulation unit 11 as demodulation reference signals for excitation signal demodulation.

[0064] (3) Demodulation Unit

[0065] The demodulation unit 7 completes the coherent demodulation of the gyro signal and calculates the digital quantities such as Cx, Cy, Sx, Sy of the gyro vibration waveform, which is consistent with the traditional hemispherical gyro demodulation unit and will not be described in detail.

[0066] (4) Excitation signal demodulation unit

[0067] The Y-axis in-phase quantity Cy calculated by the demodulation unit 7 is input to the excitation signal demodulation unit 11, and the excitation signal demodulation unit 11 completes the coherent demodulation of the excitation sinusoidal signal. The reference signal of the coherent demodulation is the sinusoidal excitation signal and the cosine signal with orthogonal phase.

[0068] The in-phase component amplitude S and the orthogonal component amplitude C of the sinusoidal excitation signal response obtained by coherent demodulation, S and C correspond to the total sinusoidal excitation signal response amplitude:

[0069]

[0070] Since the amplitude is proportional to the product of the Y-axis detection gain and the drive gain, that is, (K dY ·K sY )∝Amp, then the change of the response amplitude of the sinusoidal excitation signal relative to the amplitude reference value reflects the gain K dY ·K sY changes.

[0071] Since we have obtained in formula (5) Then we have:

[0072]

[0073] Right now:

[0074]

[0075] It is deduced that the scale factor is inversely proportional to Amp, so the scale factor can be compensated accordingly.

[0076] (5) Scale factor compensation unit

[0077] The scale factor is compensated by the extracted sinusoidal excitation signal response amplitude Amp. The sinusoidal excitation signal response amplitude Amp0 is recorded before the gyro leaves the factory, and the gyro output scale factor is K0. The sinusoidal excitation signal response amplitude Amp is calculated in real time during the gyro operation, and the scale factor of the working state is automatically compensated to the scale factor K0 before the gyro leaves the factory through the proportional relationship:

[0078] K=(Amp0 / Amp)K0 (10)

[0079] The gyro output is the precession control quantity Cp, the standard scale factor is K0, and the gyro output after automatic compensation is:

[0080]

[0081] Complete automatic compensation of the scale factor.

[0082] (6) Control unit

[0083] The low-pass filter unit 8 filters out the response of the sinusoidal excitation signal of Cx, Cy, Sx, and Sy, and then calculates the digital quantities such as amplitude, standing wave angle, standing wave angular velocity, orthogonal quantity, and phase-locked loop phase difference. The calculation method is consistent with that of the traditional hemispherical gyro demodulation unit. Since the sinusoidal excitation signal is much higher than the gyro bandwidth, after filtering the sinusoidal excitation signal, the sinusoidal excitation signal will not affect the control loop.

[0084] The control unit 10 generates the amplitude control amount Ca, the orthogonal control amount Cq, the precession control amount Cp, the phase-locked loop phase control amount L, and the reference sine-cosine signal according to the preset target value, which is consistent with the traditional hemispherical gyroscope control unit and will not be repeated here.

[0085] (7) Signal modulation unit

[0086] The signal modulation unit 13 modulates and generates a gyro drive signal according to the reference sine-cosine signal and the control quantities Ca, Cq, Cp provided by the control unit 10 and the sine excitation signal generated by the excitation signal generator, wherein the sine excitation signal is accumulated on the precession control quantity Cp. The drive signal generation method is consistent with the conventional hemispherical gyro drive method and will not be described in detail.

[0087] Example:

[0088] The hemispherical resonant gyroscope of the embodiment is made of fused quartz, has a natural frequency of 8123Hz, a metal film-coated resonator and a plate electrode form a capacitor, the gyroscope works in the X-axis and Y-axis time-sharing shared detection circuit, the X-axis and Y-axis drive circuits are independent, and the gyroscope vibration antinode is locked under the X-axis frame. The X-axis and Y-axis are switched by switches 3 and 4 to perform signal detection in time-sharing, and the frequency of time-sharing operation is 200Hz, that is, the X-axis detection is 5ms, the Y-axis detection is 5ms, and the detection is continuously alternated.

[0089] The frequency of the sinusoidal excitation signal is 1000Hz, generating a sinusoidal digital signal D0, and the corresponding analog amplitude is 100mV, which is superimposed on the gyro precession control quantity Cp, and after modulation, the analog signal is generated by the digital-to-analog converter and applied to the Y-axis electrode. The sinusoidal excitation signal can be applied continuously, or it can be applied only according to specific requirements when the scale factor needs to be self-compensated. In this example, the sinusoidal excitation signal is applied continuously.

[0090] During the factory calibration phase, the gyro is powered on and preheated for 30 minutes at room temperature to put the gyro in a thermal equilibrium state. The gyro vibration signal is detected by the buffer amplifier and the analog-to-digital converter, and the gyro demodulation is performed by the demodulation unit 7. The Y-axis in-phase quantity Cy calculated by the demodulation unit 7 is input into the excitation signal demodulation unit 11, and the sine and cosine components of the excitation signal response are extracted by coherent demodulation. The other path is sent to the low-pass filter to filter out the excitation signal and then enter the control unit for control quantity calculation. The bandwidth of the low-pass filter is set to 80Hz.

[0091] The excitation signal demodulation unit coherently demodulates the gyro vibration signal and the sinusoidal excitation signal, and extracts the sine component S0 and cosine component C0 of the response of the Y-axis excitation signal, whose average values ​​within 1 minute are S0=8.126986 and C0=3.913758.

[0092] The specific values ​​of S0 and C0 are determined by the gyro gain, analog circuit and digital processing. Due to the delay of analog and digital circuits and the delay of two coherent demodulation digital signal processing, there is a phase difference between the response signal and the sinusoidal excitation signal. The two are not completely in phase, and the total response sine wave amplitude needs to be synthesized. Calculate the total response sine wave amplitude:

[0093]

[0094] The sinusoidal excitation signal response Amp0 during the factory calibration phase is recorded as the amplitude reference value, and the gyro output Cp in this state is adjusted to the standard scale factor 20000LSB / (° / s).

[0095] In an actual work, a sinusoidal excitation signal was applied in the same way, and the sine component S and cosine component C of the response of the Y-axis sinusoidal excitation signal were demodulated and extracted. The average values ​​within 1 minute were S=8.078224 and C=3.889257.

[0096] Calculate the total response sine wave amplitude

[0097]

[0098] The precession control amount Cp is adjusted to compensate the scale factor as follows:

[0099]

[0100] The self-compensation of the scale factor is realized. In this embodiment, the self-compensation cycle of the scale factor is once every 1 minute, and the self-compensation cycle can be adjusted according to actual needs.

[0101] The present invention enables the gyroscope to work in the X-axis and Y-axis time-sharing shared detection circuit, the X-axis and Y-axis drive circuits are independent, the gyroscope vibration antinode is locked under the framework of the X-axis, and the gyroscope scale factor is inversely proportional to the product of the detection gain and the Y-axis drive gain under the framework. By applying a sinusoidal excitation signal to the precession control loop, the standing wave angle of the gyroscope undergoes sinusoidal periodic precession, and the amplitude Amp of the sinusoidal excitation signal response is extracted, and its magnitude is proportional to the product of the detection gain and the Y-axis drive gain. The change of Amp reflects the change of the gain product and also reflects the change of the scale factor. By comparing with the amplitude reference value Amp0 of the sinusoidal excitation signal response recorded before the gyroscope leaves the factory, the scale factor of the working state is automatically compensated to the scale factor K0 of the gyroscope before leaving the factory. At the same time, the response component of the sinusoidal excitation signal is deducted by a low-pass filter, which will not affect the gyroscope control and will not affect the gyroscope output.

[0102] The above embodiments of the present invention are merely examples for illustrating the present invention, and are not intended to limit the embodiments of the present invention. For those skilled in the art, other different forms of changes and modifications can be made based on the above description. It is impossible to list all the embodiments here. Any obvious changes or modifications derived from the technical solution of the present invention are still within the scope of protection of the present invention.

Claims

1. A hemispherical resonant gyro scale factor self-compensation system, characterized in that: It includes a resonator, an electrode, a switch, a buffer amplifier, an analog-to-digital converter, a demodulation unit, a low-pass filtering unit, an excitation signal generator, a control unit, an excitation signal demodulation unit, a scale factor compensation unit, a signal modulation unit, an X-axis digital-to-analog converter and a Y-axis digital-to-analog converter; the electrode is composed of an X-axis electrode and a Y-axis electrode; The X-axis electrode and the Y-axis electrode are respectively connected to the buffer amplifier through a switch, the output of the buffer amplifier is connected to the analog-to-digital converter, and the output of the analog-to-digital converter is connected to the demodulation unit; the demodulation unit has two outputs, one output is connected to the excitation signal demodulation unit and the scale factor compensation unit in sequence; the other output of the demodulation unit is connected to the control unit through a low-pass filter unit, the output of the control unit is connected to the scale factor compensation unit and two signal modulation units, one of the signal modulation unit outputs is connected to the X-axis electrode through the X-axis digital-to-analog converter, and the other signal modulation unit output is connected to the Y-axis electrode through the Y-axis digital-to-analog converter; the output of the excitation signal generator is connected to the signal modulation unit corresponding to the Y axis and the excitation signal demodulation unit.

2. A hemispherical resonant gyroscope scale factor self-compensation method, characterized in that: The scale factor self-compensation system of a hemispherical resonant gyroscope according to claim 1 is implemented by the following specific steps: S1. The hemispherical resonant gyroscope works on the X and Y axes in a time-sharing manner, using a detection circuit composed of a buffer amplifier and an analog-to-digital converter. The X and Y axis drive circuits are independent, and the gyroscope vibration antinode is locked under the X axis frame. S2. Record the hemispherical resonant gyroscope before leaving the factory: superimpose the preset sinusoidal excitation signal with the standing wave precession drive signal, generate a drive digital signal through the signal modulation unit, convert it into an analog signal through the Y-axis digital-to-analog converter, and then apply it to the Y-axis electrode; S3, switch the X-axis electrode and the Y-axis electrode by a switch, so that the X-axis and the Y-axis share the detection circuit in a time-sharing manner; the vibration signal of the resonator is converted into an analog voltage signal by a buffer amplifier, converted into a digital signal by an analog-to-digital converter, and completed with coherent demodulation at the gyro frequency by a demodulation unit, and the demodulation result is divided into two paths, one of which is extracted by an excitation signal demodulation unit to extract the Y-axis sinusoidal excitation signal response amplitude Amp0 as an amplitude reference value; the other is sent to a low-pass filter to filter out the sinusoidal excitation signal and then enters the control unit for control quantity resolution; the hemispherical resonant gyro scale factor corresponding to the amplitude reference value is recorded as K0; S4, in the working state of the gyroscope, the X-axis electrode and the Y-axis electrode are switched by the switch, so that the X-axis and the Y-axis share the detection circuit in a time-sharing manner; the vibration signal is converted into an analog voltage signal by the buffer amplifier, converted into a digital signal by the analog-to-digital converter, and completed with coherent demodulation at the gyroscope frequency by the demodulation unit. The demodulation result is divided into two paths, one of which is extracted by the excitation signal demodulation unit to extract the Y-axis sinusoidal excitation signal response amplitude Amp; the other path is sent to the low-pass filter to filter out the sinusoidal excitation signal and then enters the control unit for control amount solution to obtain the precession control amount Cp; S5, the change of Amp relative to Amp0 is the gain change, and the scale factor changes from K0 before leaving the factory to K = (Amp0 / Amp)K0; the scale factor compensation unit adjusts the precession control amount Cp to And output, completing the automatic compensation of the scale factor; S6. Repeat steps S4 and S5 to automatically update the scale factor according to the set period, thus completing the scale factor self-compensation.

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