Hemispherical resonant gyroscope error self-excitation method and system

Abstract

The embodiment of the present invention discloses a hemispherical resonant gyroscope error self-excitation method and system. The hemispherical resonant gyroscope error self-excitation method includes: after the resonator starts to vibrate, the resonator is controlled to maintain vibration through an amplitude control loop; a constant self-excitation angular velocity is added at a predetermined time, a virtual Coriolis voltage signal is generated through a self-excitation control module, a virtual Coriolis force is generated according to the virtual Coriolis voltage signal, and an electrostatic feedback force is generated through a force feedback control loop according to the virtual Coriolis force; according to the electrostatic feedback force, the electrostatic feedback force is demodulated through an orthogonal demodulation reference signal, the input angular velocity of the resonator is detected, the gyro sensitive angular velocity output under self-excitation is obtained, and the rate Coriolis vibration gyroscope error self-excitation is executed. Through the present invention, the problem of low gyroscope output accuracy due to the inability to realize gyroscope disassembly-free calibration in the prior art is solved, and the technical effect of improving the gyroscope zero bias identification accuracy is achieved.

Description

Technical Field

[0001] The invention relates to the application field of inertial instrument technology, and in particular to a hemispherical resonant gyroscope error self-excitation method and system. Background Art

[0002] Gyroscope zero bias and other parameters will drift during long-term storage and use, seriously affecting its accuracy. Most existing gyroscopes, including hemispherical, optical fiber, laser, micro-electromechanical, micro-hemisphere and other types, are passive gyroscopes and cannot complete self-excitation of disassembly-free errors. They need to use high-precision external mechanisms (such as turntables, etc.) to excite their internal errors in order to maintain high accuracy throughout their life cycle. For a single meter, regular disassembly and calibration of the gyroscope has high maintenance costs, large workloads, and reduced flexibility and speed of use; for an inertial navigation system that uses the gyroscope as an angle sensor, it is impossible to complete the disassembly and calibration of a single gyroscope meter. The system-level calibration using a rotating frame or turntable requires the separation of high-dimensional error parameters in the inertial navigation system, which takes a long time and has no significant effect on improving the gyroscope zero bias accuracy.

[0003] The problem of low output accuracy of the gyroscope due to the inability to implement gyroscope calibration without disassembly in the current related technologies has not yet been effectively solved. Summary of the invention

[0004] The embodiments of the present invention provide a hemispherical resonant gyroscope error self-excitation method and system, so as to at least solve the problem in the prior art that the gyroscope output precision is low due to the inability to implement the gyroscope disassembly-free calibration.

[0005] According to one aspect of an embodiment of the present invention, a hemispherical resonant gyroscope error self-excitation system is provided, comprising: a resonator, an amplitude control loop, a frequency-phase tracking loop, a self-excitation control module and a force feedback control loop, wherein the resonator is driven by a driving motor to make the resonator vibrate, and the amplitude control loop controls the resonator to keep vibrating, and the frequency-phase tracking loop monitors the frequency and phase of the driving modal vibration signal to generate a demodulation reference signal; a constant self-excitation angular velocity is added at a predetermined time, a virtual Coriolis voltage signal is generated by the self-excitation control module, a virtual Coriolis force is generated according to the virtual Coriolis voltage signal, and an electrostatic feedback force is generated according to the virtual Coriolis force through the force feedback control loop; according to the electrostatic feedback force, the electrostatic feedback force is demodulated through an orthogonal demodulation reference signal, the input angular velocity of the resonator is detected, the gyro sensitive angular velocity output under self-excitation is obtained, and the rate Coriolis vibration gyroscope error self-excitation is performed.

[0006] Optionally, the hemispherical resonant gyro error self-excitation system also includes: a signal demodulation module and a quasi-orthogonal control loop, wherein, in the force balance mode, the signal demodulation module generates the control judgment quantity required by the amplitude control loop, the frequency-phase tracking loop, the force feedback control loop and the quasi-orthogonal control loop; the frequency-phase tracking loop tracks the frequency and phase of the x-axis signal to generate a demodulation reference signal; the amplitude control loop controls the amplitude of the x-axis signal to be within a range near a given reference amplitude; the force feedback control loop suppresses the vibration amplitude of the y-axis signal caused by the Coriolis effect; the quasi-orthogonal control loop suppresses the vibration amplitude of the y-axis signal caused by the frequency splitting; and the virtual Coriolis force generated by the self-excitation control module acts in the y-axis direction together with the electrostatic feedback force and the quasi-orthogonal control force.

[0007] According to another aspect of an embodiment of the present invention, a hemispherical resonant gyroscope error self-excitation method is provided, which is applied to a hemispherical resonant gyroscope error self-excitation system, comprising: step 1, after the resonator starts to oscillate, controlling the resonator to maintain vibration through an amplitude control loop; step 2, adding a constant self-excitation angular velocity at a predetermined time, generating a virtual Coriolis voltage signal through a self-excitation control module, generating a virtual Coriolis force based on the virtual Coriolis voltage signal, and generating an electrostatic feedback force through a force feedback control loop based on the virtual Coriolis force; step 3, based on the electrostatic feedback force, demodulating the electrostatic feedback force through an orthogonal demodulation reference signal, detecting the input angular velocity of the resonator, obtaining the gyro sensitive angular velocity output under self-excitation, and executing rate Coriolis vibration gyroscope error self-excitation.

[0008] Optionally, after the resonator starts to oscillate, controlling the resonator to keep vibrating through the amplitude control loop includes: driving the resonator through a driving motor to make the resonator oscillate, and controlling the resonator to keep vibrating through the amplitude control loop.

[0009] Further, optionally, driving the resonator by driving the motor so that the resonator oscillates includes: driving the resonator by driving the motor so that the vibration amplitude of the resonator on the x-axis gradually increases from 0 to a range near the reference amplitude.

[0010] Optionally, the method further includes: monitoring the frequency and phase of the driving modal vibration signal through a frequency-phase tracking loop to generate a demodulation reference signal.

[0011] Further, optionally, the frequency is in a range near the natural resonant frequency of the driving modal signal.

[0012] Optionally, the working mode of step 1 includes: the hemispherical resonant gyroscope works in an open-loop mode without external angular velocity input, and the steady-state response of the driving / detecting modal vibration displacement in the open-loop mode without external angular velocity input is:

[0013]

[0014] Where x and y represent the vibration displacement signals detected at 0° and 45° of the hemispherical resonator, respectively, and Q x and Q y is the quality factor of vibration in the x-axis and y-axis directions, ω x and ω y is the angular frequency of vibration in two directions, ω d It is the driving mode vibration angular frequency tracked by the frequency-phase tracking loop, and the angular frequency is used as the angular frequency of each alternating driving force.

[0015] Optionally, the working mode of step 2 includes: the hemispherical resonant gyroscope works in an open-loop mode in which the virtual Coriolis force acts in the direction of the electrode axis at 45°, and the steady-state response of the driving / detecting modal vibration displacement in the open-loop mode is:

[0016]

[0017] in,

[0018]

[0019] Optionally, the working mode of step 3 includes: the hemispherical resonant gyroscope works in a force balance mode, and the steady-state response of the driving / detecting modal vibration displacement in the force balance mode is:

[0020]

[0021] in,

[0022]

[0023] In the embodiment of the present invention, the resonator is driven by a driving motor to make the resonator vibrate, and the amplitude control loop is used to control the resonator to keep vibrating, and the frequency-phase tracking loop monitors the frequency and phase of the driving modal vibration signal to generate a demodulation reference signal; a constant self-excitation angular velocity is added at a predetermined time, a virtual Coriolis voltage signal is generated by a self-excitation control module, a virtual Coriolis force is generated according to the virtual Coriolis voltage signal, and an electrostatic feedback force is generated according to the virtual Coriolis force through a force feedback control loop; according to the electrostatic feedback force, the electrostatic feedback force is demodulated through an orthogonal demodulation reference signal, the input angular velocity of the resonator is detected, the gyro sensitive angular velocity output under self-excitation is obtained, and the rate Coriolis vibration gyro error self-excitation is performed. In other words, the embodiment of the present invention can solve the problem of low output accuracy of the gyroscope due to the inability to realize the gyroscope disassembly-free calibration in the prior art, thereby achieving the technical effect of improving the zero bias identification accuracy of the gyroscope. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] The drawings described herein are used to provide a further understanding of the present invention and constitute a part of this application. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation of the present invention. In the drawings:

[0025] Figure 1 A schematic diagram of a hemispherical resonant gyroscope error self-excitation system provided by an embodiment of the present invention;

[0026] Figure 2 A schematic diagram of the basic working principle of a hemispherical resonant gyro error self-excitation system provided by an embodiment of the present invention;

[0027] Figure 3 A schematic diagram of realizing rate HRG error self-excitation in a hemispherical resonant gyro error self-excitation system provided by an embodiment of the present invention;

[0028] Figure 4 A schematic diagram of a simulation model diagram of a rate HRG control system with a self-excitation control module in a hemispherical resonant gyro error self-excitation system provided by an embodiment of the present invention;

[0029] Figure 5 A diagram showing the accuracy and stability of the gyro sensitive angular velocity output when the self-excitation angular velocity input is +10° / s in a hemispherical resonant gyro error self-excitation system provided by an embodiment of the present invention;

[0030] Figure 6 A schematic diagram of a rate HRG error self-excitation implementation principle in a hemispherical resonant gyro error self-excitation system provided by an embodiment of the present invention;

[0031] Figure 7 A schematic flow chart of a hemispherical resonant gyroscope error self-excitation method provided by an embodiment of the present invention;

[0032] Figure 8 A schematic diagram of a HRG dynamics simulation model in a hemispherical resonant gyroscope error self-excitation method provided in an embodiment of the present invention. DETAILED DESCRIPTION

[0033] In order to enable those skilled in the art to better understand the scheme of the present invention, the technical scheme in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work should fall within the scope of protection of the present invention.

[0034] It should be noted that the terms "first", "second" and the like in the specification, claims and drawings of the present invention are used to distinguish different objects rather than to limit a specific order.

[0035] According to one aspect of an embodiment of the present invention, a system for self-excitation of hemispherical resonant gyroscope errors is provided. Figure 1 A schematic diagram of a hemispherical resonant gyro error self-excitation system provided by an embodiment of the present invention. Figure 1 As shown, the embodiment of the present application provides a system for hemispherical resonant gyroscope error self-excitation, including:

[0036] A resonator 10, an amplitude control loop 12, a frequency-phase tracking loop 14, a self-excitation control module 16 and a force feedback control loop 18, wherein the resonator 10 is driven by a driving motor to start the resonator 10, and the amplitude control loop 12 controls the resonator 10 to keep vibrating, and the frequency-phase tracking loop 14 monitors the frequency and phase of the driving modal vibration signal to generate a demodulation reference signal; a constant self-excitation angular velocity is added at a predetermined time, a virtual Coriolis voltage signal is generated by the self-excitation control module 16, a virtual Coriolis force is generated according to the virtual Coriolis voltage signal, and an electrostatic feedback force is generated according to the virtual Coriolis force through the force feedback control loop 18; according to the electrostatic feedback force, the electrostatic feedback force is demodulated through the orthogonal demodulation reference signal, the input angular velocity of the resonator 10 is detected, the gyro sensitive angular velocity output under self-excitation is obtained, and the rate Coriolis vibration gyro error self-excitation is executed.

[0037] Optionally, the system for hemispherical resonant gyroscope error self-excitation provided in the embodiment of the present application also includes: a signal demodulation module and a quasi-orthogonal control loop, wherein, in the force balance mode, the signal demodulation module generates the control judgment quantity required by the amplitude control loop 12, the frequency-phase tracking loop 14, the force feedback control loop 18 and the quasi-orthogonal control loop; the frequency-phase tracking loop 14 tracks the frequency and phase of the x-axis signal to generate a demodulation reference signal; the amplitude control loop 12 controls the amplitude of the x-axis signal to be in the vicinity of a given reference amplitude; the force feedback control loop 18 suppresses the vibration amplitude of the y-axis signal caused by the Coriolis effect; the quasi-orthogonal control loop suppresses the vibration amplitude of the y-axis signal caused by frequency splitting; and the virtual Coriolis force generated by the self-excitation control module 16 acts together with the electrostatic feedback force and the quasi-orthogonal control force in the y-axis direction.

[0038] Specifically, the embodiment of the present application provides a system for hemispherical resonant gyroscope error self-excitation, which is based on the physical characteristics of the Coriolis vibration gyroscope, making it possible to complete the task of internal error self-excitation. The basic working principle of the typical representative hemispherical resonant gyroscope (HRG) in Coriolis vibration gyroscope is as shown in the attached figure. Figure 2 shown. Figure 2A schematic diagram of the basic working principle of HRG in a hemispherical resonator gyroscope error self-excitation system provided by an embodiment of the present invention. When there is an external angular velocity excitation, the particles on the hemispherical resonator 10 after the vibration not only move radially but also move in a circular motion, thereby generating a Coriolis acceleration a c =2Ω×v and Coriolis force F c =-2mΩ×v. The effect of Coriolis force is shown in the attached figure. Figure 2 As shown by the dashed arrow in the middle, the resonator 10 is forced to move in an elliptical shape in the direction of 45° with the antinode axis of the main wave, that is, an orthogonal wave is generated. In the force balance mode, the antinode of the main wave is always locked in the 0° direction, and the electrostatic feedback force f applied in the 45° direction y , which can suppress the orthogonal wave vibration displacement generated by the Coriolis effect, according to the electrostatic feedback force f y The size and direction of the Coriolis force can be determined, thereby realizing the detection of the input angular velocity.

[0039] The implementation process of the hemispherical resonant gyroscope error self-excitation system provided in the embodiment of the present application is as follows:

[0040] 1) The driving electrode applies force to make the resonator 10 vibrate, and the x-axis vibration amplitude gradually increases from 0 to a reference amplitude of about 10 μm, and the amplitude control loop 12 is used to maintain the vibration of the resonator 10. The whole process takes about 6 seconds. Figure 3 As shown in (a)(c)(d), Figure 3 (a)-(i) are schematic diagrams of realizing rate HRG error self-excitation in a hemispherical resonant gyro error self-excitation system provided by an embodiment of the present invention;

[0041] 2) The frequency-phase tracking loop 14 tracks the frequency and phase of the driving modal vibration signal and generates a demodulation reference signal, the signal frequency of which is near the natural resonant frequency of the driving modal signal, 4964.7 Hz. The tracking process is very fast and is completed within 0.5 s after power-on. Figure 3 (b)

[0042] 3) At 10s, apply Figure 3 (e) shows a constant self-excitation angular velocity of 10° / s (within the range of the rate HRG sensitive angular velocity capability), and a virtual Coriolis voltage signal is generated by the self-excitation control module 16. Figure 4 , Figure 4 FIG. 1 is a schematic diagram of a rate HRG control system simulation model diagram with a self-excitation control module in a hemispherical resonant gyro error self-excitation system provided by an embodiment of the present invention. The rate HRG control system simulation model is used to generate a virtual Coriolis force radially outward along the equator, as shown in FIG. Figure 3(f) shows that it acts in the y-axis direction, that is, it acts on the detection mode. The virtual Coriolis force applied in this process is equivalent to the effect of the real Coriolis force under external angular velocity excitation. The state of the resonator 10 at the initial phase is shown in the attached figure. Figure 2 As shown in (a), when a positive angular velocity excitation is applied in this state, a Coriolis force radially outward along the equator will be generated in the 45° direction to change the resonant vibration state of the standing wave on the resonator 10;

[0043] 4) The virtual Coriolis force can generate orthogonal waves caused by the Coriolis effect, and the force feedback control loop 18 generates an electrostatic feedback force, such as the attached Figure 3 As shown in (h), it acts in the y-axis direction to suppress the vibration displacement in the y-axis direction caused by the virtual Coriolis force and the unequal damping error inside the gyroscope;

[0044] 5) According to the magnitude and direction of the electrostatic feedback force, the orthogonal demodulation reference signal can be used to demodulate the electrostatic feedback force, realize the detection of the input angular velocity, and obtain the gyro sensitive angular velocity output under self-excitation, as shown in the attached figure. Figure 3 As shown in (i), the rate HRG error self-excitation is completed.

[0045] By the attached Figure 5 It can be seen that Figure 5 A diagram of the accuracy and stability of the gyroscope sensitive angular velocity output when the self-excitation angular velocity input is +10° / s in a hemispherical resonator gyroscope error self-excitation system provided in an embodiment of the present invention. When a hemispherical resonator 10 dynamic simulation model without non-equidamping and non-equielastic errors is used to simulate and verify the rate HRG error self-excitation method, when the self-excitation angular velocity input is a positive rotation of 10° / s, the absolute value of the gyroscope sensitive angular velocity output error is less than 0.001° / s, and the output stabilization time is about 31s, which proves the feasibility of the method proposed in the present invention from principle to specific implementation.

[0046] In the force balance mode, the driving mode is locked in the x-axis direction, the detection mode is locked in the y-axis direction and the amplitude is suppressed to almost 0 ( tends to 0), so it is only necessary to apply a driving force in the y-axis direction to achieve the self-excitation of the rate HRG error and reflect the error in the electrostatic feedback force. In order to apply the above virtual Coriolis force, the first task is to obtain the vibration velocity information of the x-axis. There are two ways, Figure 6 A schematic diagram of the implementation principle of the rate HRG error self-excitation in a hemispherical resonant gyro error self-excitation system provided by an embodiment of the present invention, as shown in the attached Figure 6 As shown by the dotted line, the x-axis vibration displacement signal is directly extracted and generated by the differentiator Method 2 as attached Figure 6 As shown by the solid line, the gyro internal amplitude signal and demodulation reference signal are used to generate Since the second method has significant advantages such as higher signal update frequency, no need to modify the existing HRG control circuit board structure, and no introduction of differentiator error, the present invention adopts this method to extract the x-axis vibration velocity information. It is worth noting that the accuracy of the signal extraction depends on the accuracy of the internal reference information, that is, there are corresponding requirements for the control accuracy of basic loops such as frequency and phase tracking.

[0047] On the basis of the existing force balance mode HRG control circuit, it is necessary to add a self-excitation control module through a control algorithm to complete the application of the virtual Coriolis force in the y-axis direction, and make the y-axis steady-state response generated by the driving force equivalent to the influence of the real Coriolis force generated by the fixed-axis rotation of the rate HRG.

[0048] The embodiments of the present application provide a hemispherical resonant gyro error self-excitation system, which cleverly utilizes the Coriolis effect to completely get rid of the dependence of the rate HRG error excitation on an external high-precision reference, and can complete the self-calibration of the rate HRG constant scale factor and the zero bias error on this basis, so as to achieve high-precision maintenance without disassembly throughout the life cycle of the gyro, thereby improving the flexibility, accuracy and rapidity of the use of a single meter and a platform inertial navigation system using it as an angle sensor.

[0049] In the embodiment of the present invention, the resonator is driven by a driving motor to make the resonator vibrate, and the amplitude control loop is used to control the resonator to keep vibrating, and the frequency-phase tracking loop monitors the frequency and phase of the driving modal vibration signal to generate a demodulation reference signal; a constant self-excitation angular velocity is added at a predetermined time, a virtual Coriolis voltage signal is generated by a self-excitation control module, a virtual Coriolis force is generated according to the virtual Coriolis voltage signal, and an electrostatic feedback force is generated according to the virtual Coriolis force through a force feedback control loop; according to the electrostatic feedback force, the electrostatic feedback force is demodulated through an orthogonal demodulation reference signal, the input angular velocity of the resonator is detected, the gyro sensitive angular velocity output under self-excitation is obtained, and the rate Coriolis vibration gyro error self-excitation is performed. In other words, the embodiment of the present invention can solve the problem of low output accuracy of the gyroscope due to the inability to realize the gyroscope disassembly-free calibration in the prior art, thereby achieving the technical effect of improving the zero bias identification accuracy of the gyroscope.

[0050] According to one aspect of an embodiment of the present invention, a hemispherical resonant gyroscope error self-excitation method is provided. Figure 7 A schematic diagram of a flow chart of a hemispherical resonant gyroscope error self-excitation method provided by an embodiment of the present invention. Figure 7 As shown, applied to the above-mentioned hemispherical resonant gyro error self-excitation system, the embodiment of the present application provides a hemispherical resonant gyro error self-excitation method including:

[0051] Step 1, after the resonator starts to vibrate, the resonator is controlled to maintain vibration through an amplitude control loop;

[0052] Optionally, after the resonator starts to oscillate, controlling the resonator to keep vibrating through the amplitude control loop includes: driving the resonator through a driving motor to make the resonator oscillate, and controlling the resonator to keep vibrating through the amplitude control loop.

[0053] Further, optionally, driving the resonator by driving the motor so that the resonator oscillates includes: driving the resonator by driving the motor so that the vibration amplitude of the resonator on the x-axis gradually increases from 0 to a range near the reference amplitude.

[0054] Step 2, adding a constant self-excitation angular velocity at a predetermined time, generating a virtual Coriolis voltage signal through a self-excitation control module, generating a virtual Coriolis force according to the virtual Coriolis voltage signal, and generating an electrostatic feedback force through a force feedback control loop according to the virtual Coriolis force;

[0055] Step 3, based on the electrostatic feedback force, the electrostatic feedback force is demodulated by orthogonal demodulation reference signal, the input angular velocity of the resonator is detected, the gyro sensitive angular velocity output under self-excitation is obtained, and the rate Coriolis vibration gyro error self-excitation is executed.

[0056] Optionally, the hemispherical resonant gyroscope error self-excitation method provided in the embodiment of the present application also includes: monitoring the frequency and phase of the driving modal vibration signal through a frequency-phase tracking loop to generate a demodulation reference signal.

[0057] Further, optionally, the frequency is in a range near the natural resonant frequency of the driving modal signal.

[0058] Optionally, the working mode of step 1 includes: the hemispherical resonant gyroscope works in an open-loop mode without external angular velocity input, and the steady-state response of the driving / detecting modal vibration displacement in the open-loop mode without external angular velocity input is:

[0059]

[0060] Where x and y represent the vibration displacement signals detected at 0° and 45° of the hemispherical resonator, respectively, and Q x and Q y is the quality factor of vibration in the x-axis and y-axis directions, ω x and ω y is the angular frequency of vibration in two directions, ω d It is the driving mode vibration angular frequency tracked by the frequency-phase tracking loop, and the angular frequency is used as the angular frequency of each alternating driving force.

[0061] Optionally, the working mode of step 2 includes: the hemispherical resonant gyroscope works in an open-loop mode in which the virtual Coriolis force acts in the direction of the electrode axis at 45°, and the steady-state response of the driving / detecting modal vibration displacement in the open-loop mode is:

[0062]

[0063] in,

[0064]

[0065] Optionally, the working mode of step 3 includes: the hemispherical resonant gyroscope works in a force balance mode, and the steady-state response of the driving / detecting modal vibration displacement in the force balance mode is:

[0066]

[0067] in,

[0068]

[0069] In summary, combined with steps 1 to 3, the realization of rate HRG error self-excitation is mainly divided into the following four stages: 1) the resonator starts to oscillate; 2) the resonator maintains vibration; 3) the x-axis vibration velocity signal is extracted to generate a virtual Coriolis force acting in the y-axis direction; 4) the force feedback control loop is used to generate an electrostatic feedback force to suppress the amplitude in the y-axis direction, obtain the magnitude and direction of the electrostatic feedback force in the stable state, and reflect the gyro error in the electrostatic feedback force.

[0070] The above four stages include three working modes. In the first and second stages, HRG works in open-loop mode without external angular velocity input. In the third stage, HRG works in open-loop mode under the action of virtual Coriolis force in the y-axis direction. In the fourth stage, HRG works in force balance mode. The steady-state response of vibration displacement in the three modes is as follows:

[0071] 1) Open-loop mode without external angular velocity input:

[0072]

[0073] Where x and y represent the vibration displacement signals detected at 0° and 45° of the hemispherical resonator, respectively, and Q x and Q y is the quality factor of vibration in the x-axis and y-axis directions, ω x and ω y is the angular frequency of vibration in two directions, ω d It is the driving mode vibration angular frequency tracked by the frequency-phase tracking loop, which will also be used as the angular frequency of each alternating driving force;

[0074] 2) Open-loop mode with virtual Coriolis force in the y-axis direction:

[0075]

[0076] in,

[0077]

[0078] 3) Force balance mode:

[0079]

[0080] in,

[0081]

[0082] The control principle of the rate HRG system with self-excitation control module is shown in the attached Figure 1 As shown, in the force balance mode, the signal demodulation module generates the control judgment required by each loop; the frequency-phase tracking loop tracks the frequency and phase of the x-axis signal to generate a demodulation reference signal; the amplitude control loop controls the x-axis signal amplitude to be near a given reference amplitude; the force feedback control loop suppresses the vibration amplitude of the y-axis signal caused by the Coriolis effect; the quasi-orthogonal control loop suppresses the vibration amplitude of the y-axis signal caused by frequency splitting; the virtual Coriolis force generated by the self-excitation control module acts on the y-axis direction together with the electrostatic feedback force and the quasi-orthogonal control force.

[0083] In order to complete the execution and simulation verification of the rate HRG error self-excitation control scheme, the present invention uses simulink to construct an HRG dynamics simulation model and a rate HRG control system simulation model with a self-excitation control module, as shown in Figure 2. Figure 8 Shown and attached Figure 4 shown. Figure 8 A schematic diagram of a HRG dynamics simulation model in a hemispherical resonant gyro error self-excitation method provided in an embodiment of the present invention. The mathematical model form of the constructed HRG dynamics simulation model is as follows:

[0084]

[0085] This model can characterize the actual working state of the hemispherical resonator. Among them, x and y represent the vibration displacement signals detected at 0° and 45° directions of the hemispherical resonator, respectively, and f x 、f y are the electrostatic driving force and electrostatic feedback force applied by the driving electrodes in the x and y directions respectively, and is the Coriolis force coupling term generated by the Coriolis effect, K is the precession factor, Ω is the excitation angular velocity; τ is the oscillation decay time constant, Where τ1 and τ2 are the oscillation decay time constants of the oscillator on the maximum and minimum “damped normal axis”, respectively. is the unequal damping error coefficient, θ τ is the angle between the maximum damping axis and the x-axis, Where ω1 and ω2 are the natural vibration angular frequencies of the oscillator on the maximum and minimum "normal axis of stiffness" respectively, Δω is the non-isoelastic error coefficient, θ ω is the angle between the minimum stiffness axis and the x-axis.

[0086] In the force balance mode, the driving mode is locked in the 0° electrode axis direction, the detection mode is locked in the 45° electrode axis direction and the amplitude is almost suppressed to 0. It is only necessary to apply the driving force in the 45° direction to realize the self-excitation of the rate hemispherical resonant gyro error. The application of the virtual Coriolis force requires the extraction of the vibration velocity information in the 0° electrode axis direction. The method of generating the above-mentioned vibration velocity information by using the reference demodulation signal output by the frequency-phase tracking loop and the driving mode vibration amplitude signal output by the signal demodulation module has the significant advantages of high signal update frequency, no need to modify the existing control circuit board structure, and no introduction of differentiator error. On the basis of the existing force balance mode control circuit, a self-excitation control module is added through the control algorithm design. The module uses the internal resonant frequency of the gyroscope, the driving mode vibration amplitude, the demodulation reference signal and other information to generate a virtual Coriolis voltage signal, complete the application of the virtual Coriolis force in the 45° electrode axis direction, and make the steady-state response in this direction generated by the driving force equivalent to the influence of the real Coriolis force generated by the fixed-axis rotation of the rate hemispherical resonant gyroscope.

[0087] In the embodiment of the present invention, after the resonator starts to vibrate, the amplitude control loop is used to control the resonator to keep vibrating; a constant self-excitation angular velocity is added at a predetermined time, a virtual Coriolis voltage signal is generated through the self-excitation control module, a virtual Coriolis force is generated according to the virtual Coriolis voltage signal, and an electrostatic feedback force is generated according to the virtual Coriolis force through a force feedback control loop; according to the electrostatic feedback force, the electrostatic feedback force is demodulated through an orthogonal demodulation reference signal, the input angular velocity of the resonator is detected, the gyro sensitive angular velocity output under self-excitation is obtained, and the rate Coriolis vibration gyro error self-excitation is performed. In other words, the embodiment of the present invention can solve the problem of low gyroscope output accuracy due to the inability to realize gyroscope disassembly-free calibration in the prior art, thereby achieving the technical effect of improving the gyroscope zero bias identification accuracy.

[0088] The above description is only a preferred embodiment of the present invention and is not intended to limit the protection scope of the present invention.

Claims

1. A hemispherical resonant gyro error self-excitation method, characterized in that: Applied to hemispherical resonant gyro error self-excitation system, including: Step 1, after the resonator starts to vibrate, controlling the resonator to keep vibrating through an amplitude control loop; The working mode of step 1 includes: The hemispherical resonant gyroscope operates in an open-loop mode without external angular velocity input. The steady-state response of the driving / detecting modal vibration displacement in the open-loop mode without external angular velocity input is: Step 2, adding a constant self-excitation angular velocity at a predetermined time, generating a virtual Coriolis voltage signal through a self-excitation control module, generating a virtual Coriolis force according to the virtual Coriolis voltage signal, and generating an electrostatic feedback force through a force feedback control loop according to the virtual Coriolis force; The working mode of step 2 includes: The hemispherical resonant gyroscope operates in an open-loop mode under the action of the virtual Coriolis force in the 45° electrode axis direction. The steady-state response of the drive / detection modal vibration displacement in the open-loop mode is: in, Step 3, according to the electrostatic feedback force, by orthogonal demodulation reference signal, demodulate the electrostatic feedback force, detect the input angular velocity of the resonator, obtain the gyro sensitive angular velocity output under self-excitation, and perform rate Coriolis vibration gyro error self-excitation; The working mode of step 3 includes: The hemispherical resonant gyroscope works in a force balance mode, and the steady-state response of the driving / detecting modal vibration displacement in the force balance mode is: in, Where x and y represent the vibration displacement signals detected at 0° and 45° of the hemispherical resonator, respectively, and Q x and Q y is the quality factor of vibration in the x-axis and y-axis directions, ω x and ω y is the angular frequency of vibration in two directions, ω d It is the driving mode vibration angular frequency tracked by the frequency tracking loop, and the angular frequency is used as the angular frequency of each alternating driving force.

2. The hemispherical resonant gyro error self-excitation method according to claim 1, characterized in that: After the resonator starts to oscillate, controlling the resonator to maintain vibration through an amplitude control loop includes: The resonator is driven by a driving motor to make the resonator vibrate, and the resonator is controlled by the amplitude control loop to keep vibrating.

3. The hemispherical resonant gyro error self-excitation method according to claim 2, characterized in that: The step of driving the resonator by driving the motor so that the resonator starts to oscillate comprises: The resonator is driven by a driving motor so that the vibration amplitude of the resonator on the x-axis gradually increases from 0 to a range near a reference amplitude.

4. The hemispherical resonant gyro error self-excitation method according to claim 2, characterized in that: The method further comprises: The frequency and phase of the driving mode vibration signal are monitored through a frequency-phase tracking loop to generate a demodulation reference signal.

5. The hemispherical resonant gyro error self-excitation method according to claim 4, characterized in that: The frequency is in a range near the natural resonant frequency of the driving modal signal.

6. A hemispherical resonant gyro error self-excitation system for implementing the method described in any one of claims 1 to 5, characterized in that: include: Resonator, amplitude control loop, frequency and phase tracking loop, self-excitation control module, force feedback control loop, signal demodulation module and quasi-orthogonal control loop, wherein: The resonator is driven by a driving motor to start the resonator to vibrate, and the amplitude control loop is used to control the resonator to keep vibrating, and the frequency-phase tracking loop monitors the frequency and phase of the driving modal vibration signal to generate a demodulation reference signal; adding a constant self-excitation angular velocity at a predetermined time, generating a virtual Coriolis voltage signal through the self-excitation control module, generating a virtual Coriolis force according to the virtual Coriolis voltage signal, and generating an electrostatic feedback force through the force feedback control loop according to the virtual Coriolis force; According to the electrostatic feedback force, the electrostatic feedback force is demodulated by orthogonal demodulation reference signal, the input angular velocity of the resonator is detected, the gyro sensitive angular velocity output under self-excitation is obtained, and the rate Coriolis vibration gyro error self-excitation is performed; In the force balance mode, the signal demodulation module generates the control judgment quantity required by the amplitude control loop, the frequency phase tracking loop, the force feedback control loop and the quasi-orthogonal control loop; The frequency-phase tracking loop tracks the frequency and phase of the x-axis signal to generate a demodulation reference signal; the amplitude control loop controls the amplitude of the x-axis signal in the vicinity of a given reference amplitude; the force feedback control loop suppresses the vibration amplitude of the y-axis signal caused by the Coriolis effect; the quasi-orthogonal control loop suppresses the vibration amplitude of the y-axis signal caused by frequency splitting; the virtual Coriolis force generated by the self-excitation control module acts on the y-axis direction together with the electrostatic feedback force and the quasi-orthogonal control force.

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