A method and system for adjusting uneven damping and stiffness of a hemispherical resonant gyroscope

Abstract

A method and system for adjusting the uneven damping and stiffness of a hemispherical resonator gyroscope, specifically relating to a method and system for adjusting the uneven damping and stiffness of a hemispherical resonator of a full-angle mode hemispherical resonator gyroscope based on a parallel resistor in a detection circuit. To address the problem of periodic variation in the azimuth angle of a standing wave in the circumferential direction caused by the uneven damping and stiffness of the hemispherical resonator in the full-angle mode, resulting in low test accuracy and a sharp decline in performance of the gyroscope, the method comprises metallizing the hemispherical resonator; setting the angle between the large stiffness axis and the small damping axis of the hemispherical resonator to less than 45 degrees; connecting a flat electrode to an adjustment resistor, with the other end of the adjustment resistor grounded; setting the hemispherical resonator to a second-order four-antinode resonance state; demodulating and identifying the vibration signal of the hemispherical resonator to obtain a damping unevenness error and a stiffness deviation, then adjusting the value of the adjustment resistor, and using the value of the adjustment resistor to adjust the uneven damping and stiffness errors of the hemispherical resonator.

Description

Technical Field

[0001] The present invention relates to a method and system for adjusting the damping and stiffness unevenness of a hemispherical resonator of a hemispherical resonator gyroscope in a full-angle mode based on a parallel resistor in a detection circuit, and belongs to the field of hemispherical resonator gyroscope control. Background Art

[0002] The hemispherical resonator of a full-angle-mode HRG is always in a state of free precession. By utilizing the Coriolis force-induced precession angle of the resonator's vibration mode, which is proportional to the carrier's actual rotation angle, and calculating the gyro's vibration mode angle information, the carrier's rotation angle can be directly obtained. Therefore, the full-angle mode enables the HRG to have a high dynamic range and a stable scale factor. The perfect symmetry of the hemispherical resonator is the foundation for the high-precision performance of the full-angle-mode HRG. However, the uneven damping of the hemispherical resonator and the stiffness coupling are important factors affecting the high-precision detection performance of the full-angle-mode gyroscope. On the other hand, the standing wave of the full-angle-mode HRG precesses freely in the circumferential direction. The uneven damping causes the azimuth angle of the standing wave to vary periodically in the circumferential direction, with a strong position-angle dependence, which seriously restricts the improvement of the HRG's operating performance.

[0003] Numerous factors influence the uneven distribution of stiffness and damping in a hemispherical resonator. A major factor is the complex and multi-step process involved in manufacturing hemispherical resonators. This makes it difficult and costly to achieve high precision in each step. This places extremely high demands on each process, leading to machining errors that can cause errors in stiffness and damping. Furthermore, the damping and damping distribution of a hemispherical resonator are sensitive to changes in environmental factors such as temperature. Therefore, calibrating and compensating for damping and stiffness errors during the use of a hemispherical resonator gyroscope is crucial. Summary of the Invention

[0004] In order to solve the problem that the uneven damping and stiffness of a hemispherical resonant gyroscope in full-angle mode causes the standing wave azimuth angle to vary periodically in the circumferential direction, resulting in low gyro test accuracy and a sharp decline in performance, the present invention proposes a method and system for adjusting the uneven damping and stiffness of a hemispherical resonant gyroscope.

[0005] The technical solution adopted by the present invention is:

[0006] It includes the following steps:

[0007] S1. Perform metallization coating treatment on the inner surface, support rod and lip edge of the hemispherical resonator respectively;

[0008] S2, setting the angle between the large stiffness axis and the small damping axis of the hemispherical resonator after metallization coating treatment to be less than 45°;

[0009] S3. Divide the electrode plate on the flat electrode into a detection electrode and a driving electrode, connect the detection electrode to the adjustment resistor, and ground the other end of the adjustment resistor;

[0010] S4, setting the hemispherical resonator to a second-order four-antinode resonance state;

[0011] S5. When the detection electrode detects the vibration signal of the hemispherical resonator, the detection system of the hemispherical resonator gyroscope inputs the vibration signal into the control system for demodulation and identification to obtain the damping unevenness error and stiffness deviation;

[0012] S6. Adjust the resistance of the adjustment resistor according to the damping uneven error, and use the resistance of the adjustment resistor to adjust the damping and stiffness uneven errors of the hemispherical resonator.

[0013] Furthermore, in said S2, the angle between the large stiffness axis and the small damping axis of the hemispherical resonator after the metallization coating treatment is set to be less than 45°, and the specific process is as follows:

[0014] The hemispherical resonator treated with metallized coating is adjusted by a mechanical adjustment method, and the angle between the large stiffness axis and the small damping axis of the adjusted hemispherical resonator is less than 45 degrees.

[0015] Furthermore, the mechanical adjustment method is an ion beam method.

[0016] Furthermore, in S3, the detection electrode and the adjustment resistor are connected in parallel.

[0017] Furthermore, in S3, the electrode plate on the flat electrode is divided into a detection electrode and a driving electrode, the detection electrode is connected to the adjustment resistor, and the other end of the adjustment resistor is grounded. The specific process is:

[0018] For a hemispherical resonant gyroscope adopting a time-division multiplexing control scheme, the detection electrode is connected to the adjustment resistor through a multiplexing switch; for a hemispherical resonant gyroscope not adopting a time-division multiplexing control scheme, the detection electrode is directly connected to the adjustment resistor.

[0019] Furthermore, in S4, the hemispherical resonant gyroscope is installed, and the hemispherical resonator is set to a second-order four-antinode vibration mode resonance state. The specific process is as follows:

[0020] A high voltage is applied to the surface of the installed hemispherical resonator, and an excitation voltage signal is applied to the driving electrode to drive the hemispherical resonator into a second-order four-antinode vibration mode resonance state.

[0021] Furthermore, in S5, when the detection electrode detects the vibration signal of the hemispherical resonator, the detection system of the hemispherical resonator gyroscope inputs the vibration signal into the control system for demodulation and identification to obtain the damping unevenness error and stiffness deviation. The specific process is as follows:

[0022] When the detection electrode detects the vibration signal of the hemispherical resonator, the detection system of the hemispherical resonator gyroscope inputs the vibration signal into the control system. The control system demodulates the vibration signal using the averaging method according to the second-order vibration dynamics model of the hemispherical resonator gyroscope, and then uses the least squares method or extended Kalman filter to identify the damping of the X-axis, the damping of the Y-axis, the damping unevenness error, the stiffness deviation, and the frequency decomposition.

[0023] Furthermore, the second-order vibration dynamics model of the hemispherical resonant gyroscope is:

[0024]

[0025] Where M represents the equivalent mass of the model; Indicates vibration acceleration; represents the vibration rate; C represents the equivalent damping; coefficient ε and ε0 are dielectric constants; d0 represents the distance between the lip and the plate at rest; A represents the effective area; R xi Indicates the resistance value of the X detection circuit adjustment resistor; R yi Indicates the resistance value of the Y detection circuit adjustment resistor; u E represents the DC high voltage applied to the surface of the hemispherical resonator after metallization coating; x, y represent the vibration displacement.

[0026] Furthermore, in S6, the resistance of the adjustment resistor is adjusted according to the damping uneven error, and then the damping and stiffness uneven errors of the hemispherical resonator are adjusted using the resistance of the adjustment resistor. The specific process is as follows:

[0027] The damping of the X-axis is C(x), the damping of the Y-axis is C(y), the damping unevenness error is ΔC, and the stiffness deviation is ΔK;

[0028] Adjust the regulating resistor R of the X detection circuit according to the damping uneven error ΔC xi And the adjustment resistor R of the Y detection circuit yi Resistance value:

[0029] If C(x)-C(y)>0, then ΔR=R xi -R yi ;

[0030] If C(x)-C(y)<0, then ΔR=R yi -R xi ;

[0031] Adjustment resistor R after trimming xi ,R yi The resistance value satisfies:

[0032]

[0033] The adjustment amount of stiffness deviation is:

[0034]

[0035] Among them, ΔK≥ΔK′.

[0036] A system for adjusting the uneven damping and stiffness of a hemispherical resonator gyroscope comprises a memory, a processor, and a computer program stored in the memory and executable on the processor. When the processor executes the computer program, any step of a method for adjusting the uneven damping and stiffness of a hemispherical resonator gyroscope is implemented.

[0037] Beneficial effects:

[0038] The present invention first sets the state of a hemispherical resonator gyroscope, that is, metallization coating is performed on the inner surface, support rod, and lip edge end surface of the hemispherical resonator, and the angle between the large stiffness axis and the small damping axis of the hemispherical resonator is set to be less than 45 degrees. Then, the plate on the flat electrode is divided into a detection electrode and a drive electrode, the detection electrode is connected to an adjustment resistor through a multiplexing switch, the other end of the adjustment resistor is grounded, and the adjustment resistor is connected in parallel to a detection circuit; the hemispherical resonator is set to a second-order four-antinode vibration mode resonance state, when the detection electrode detects a vibration signal of the hemispherical resonator, the detection system of the hemispherical resonator inputs the collected vibration signal into a control system for demodulation and identification, obtains damping unevenness error and frequency cracking, adjusts the resistance value of the adjustment resistor according to the damping unevenness error and frequency cracking, and then uses the resistance value of the adjustment resistor to adjust the damping and stiffness unevenness errors of the hemispherical resonator.

[0039] The present invention collects the vibration signal of the hemispherical resonator and performs demodulation and identification to obtain the damping deviation and stiffness deviation of the hemispherical resonator. According to the damping deviation and stiffness deviation, the resistance value of the adjustment resistor connected in parallel to the detection circuit is adjusted to achieve simultaneous adjustment of the damping and stiffness uneven errors of the hemispherical resonator, which not only improves the test accuracy but also enhances the performance. The present invention does not require the addition of additional adjustment electrodes or the control of additional adjustment voltages. Damping and stiffness adjustment can be achieved by adjusting the resistor. At the same time, in the time-sharing multiplexing control scheme of the full-angle mode of the hemispherical resonator gyroscope, only a series multiplexing switch is required. The method of the present invention is simple to control and is more suitable for engineering applications. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] Figure 1 is a flow chart of the present invention;

[0041] Figure 2 It is a schematic diagram of the structure of the hemispherical resonator gyroscope and a schematic diagram of the driving and detection principles of the hemispherical resonator 1;

[0042] Figure 3This is a connection diagram of the detection electrodes, adjustment resistors, and multiplexer switches;

[0043] Figure 4 This is a schematic diagram of the principle of adjusting the resistance to change the damping distribution and stiffness distribution of the hemispherical resonant gyroscope;

[0044] Figure 5 Schematic diagram of the large stiffness axis and small damping axis of the hemispherical resonator 1; DETAILED DESCRIPTION

[0045] Specific implementation method 1: Combination Figure 1-Figure 5 This embodiment describes a method for adjusting uneven damping and stiffness of a hemispherical resonator gyroscope, which includes the following steps:

[0046] S1. Perform metallization coating treatment on the inner surface of the hemispherical resonator 1, the support rod 2, and the lip edge end surface respectively.

[0047] The hemispherical resonator gyroscope includes a hemispherical resonator 1, a flat electrode 3, a plate, a support rod 2, a lip, etc. Eight plates are installed in a circular distribution on the flat electrode 3, and the hemispherical resonator 1 is fixed to the flat electrode 3 through the support rod 2.

[0048] The metal film layer primarily increases the hemispherical resonator's sensitivity to vibration information, allowing for better output of vibration signals. However, metallization can significantly affect the distribution of damping and the damping axis. Therefore, the metallization coating must be continuous, have a uniform thickness, minimize resistance, and be as thin as possible.

[0049] S2. Setting the angle between the large stiffness axis and the small damping axis of the hemispherical resonator 1 after metallization coating treatment to be less than 45°. The specific process is as follows:

[0050] The hemispherical resonator 1 after metallization coating treatment is adjusted by mechanical adjustment method. The angle between the large stiffness axis and the small damping axis of the adjusted hemispherical resonator 1 is less than 45°. The large stiffness axis and the small damping axis are two axes distributed along the annular direction of the hemispherical resonator 1. The hemispherical resonator has two stiffness axes and two damping axes. The one with small frequency is called the large stiffness axis, and the one with large frequency is called the small stiffness axis. The damping axis is defined by the decay time constant. The one with large decay time constant is called the small damping axis, and vice versa, it is called the large damping axis, such as Figure 5 As shown, since the eight plates form a 360° angle, each adjacent plate is 45 degrees apart. In this invention, the high-stiffness axis and the low-damping axis are both located on the same plate, meaning the angle between the two axes is 0-45°. The hemispherical resonator 1 is secured to the flat electrode 3 via support rods 2, so that the lip and the plates form an equivalent capacitance. The mechanical adjustment method is an ion beam method.

[0051] S3, the electrode plate on the flat electrode 3 is divided into a detection electrode and a driving electrode, and the detection electrode is connected to an adjustment resistor, and the other end of the adjustment resistor is grounded. The detection electrode and the adjustment resistor are connected in parallel.

[0052] For hemispherical resonant gyroscopes that employ a time-sharing multiplexing control scheme, the detection electrodes are connected to the adjustment resistor via a multiplexing switch, which controls whether the adjustment resistor is connected to the circuit. For hemispherical resonant gyroscopes that do not employ a time-sharing multiplexing control scheme, the detection electrodes are directly connected to the adjustment resistor, eliminating the need for a multiplexing switch. This broadens the scope of application and facilitates engineering implementation. The eight electrodes are divided into drive electrodes and detection electrodes according to their driving and detection functions.

[0053] S4. Install the hemispherical resonant gyroscope and set the hemispherical resonator 1 to the second-order four-antinode vibration mode resonance state. The specific process is as follows:

[0054] A high voltage of 100-300 volts is applied to the surface of the installed hemispherical resonator 1 , and an excitation voltage signal is applied to the driving electrode to drive the hemispherical resonator 1 into a second-order four-antinode resonance state.

[0055] The resonant frequency in the second-order four-antinode vibration mode resonance state can avoid the frequency of adjacent modes, avoiding coupling; this modal frequency can minimize energy loss and improve the quality factor compared to high frequencies; this state is relatively stable, and the four-amplitude vibration state is easy to implement for the detection method.

[0056] S5. When the detection electrode detects the vibration signal of the hemispherical resonator 1, the detection system of the hemispherical resonator gyroscope inputs the vibration signal into the control system for demodulation and identification, and obtains the damping unevenness error and stiffness deviation. The specific process is as follows:

[0057] When the detection electrode detects the vibration signal of the hemispherical resonator 1, the detection system of the hemispherical resonator gyroscope inputs the vibration signal into the control system. The control system demodulates the vibration signal using the averaging method according to the second-order vibration dynamics model of the hemispherical resonator gyroscope, and then uses the least squares method or extended Kalman filter to identify the damping of the X-axis, the damping of the Y-axis, the damping unevenness error, the stiffness deviation, and the frequency decomposition.

[0058] Simplified second-order vibration dynamics model of hemispherical resonant gyroscope:

[0059]

[0060] in, represents the equivalent plate capacitance formed by the lip of the hemispherical resonator 1 and the plate electrode 3, ε and ε0 are dielectric constants; d0 represents the distance between the lip and the plate at rest; A represents the effective area; C represents the equivalent damping; K represents the equivalent stiffness of the model; x, y represent the vibration displacement; Vxi represents the voltage applied by the i-th plate in the x direction; V yi represents the voltage applied by the i-th plate in the y direction. M represents the equivalent mass of the model; Indicates vibration acceleration; Indicates the vibration rate;

[0061] Represents the equivalent voltage between the two plates of the equivalent flat plate capacitor; R i Indicates the resistance value of the adjustment resistor, u E represents the DC high voltage applied to the surface of the hemispherical resonator 1 after metallization coating treatment;

[0062] After further simplifying formula (1), we get:

[0063]

[0064] Among them, the coefficient

[0065] S6. Adjust the resistance of the adjustment resistor according to the damping uneven error. Use the resistance of the adjustment resistor to adjust the damping and stiffness uneven errors of the hemispherical resonator 1. The specific process is as follows:

[0066] According to the above formula (2), the adjustment resistor R i Or DC high voltage u E It can adjust the damping and stiffness. Generally, u E After setting, it will not change, so the resistor R is connected in parallel in the X detection circuit or the Y detection circuit. xi ,R yi , to achieve the adjustment of the uneven damping and stiffness of the hemispherical resonator 1, thereby achieving the electrostatic adjustment of the damping uneven error and frequency splitting.

[0067] The damping of the X-axis is C(x), the damping of the Y-axis is C(y), the damping unevenness error is ΔC, and the stiffness deviation is ΔK.

[0068] Compare the X-axis damping C(x) and the Y-axis damping C(y), that is, adjust the adjustment resistor R of the X detection circuit according to the damping uneven error ΔC. xi And the adjustment resistor R of the Y detection circuit yi Resistance value:

[0069] If C(x)-C(y)>0, then ΔR=R xi -R yi ;

[0070] If C(x)-C(y)<0, then ΔR=R yi -R xi ;

[0071] Since stiffness deviation leads to frequency cracking, frequency cracking can be obtained after obtaining stiffness deviation. However, adjusting resistance cannot directly adjust frequency cracking, so frequency cracking is adjusted by changing stiffness, that is, the adjustment of stiffness and the adjustment of frequency cracking are equivalent.

[0072] Adjustment resistor R after trimming xi ,R yi The resistance values of the two resistors satisfy the following relationship:

[0073]

[0074] At this time, the adjustment amount of stiffness deviation is:

[0075]

[0076] Among them, ΔK≥ΔK′.

[0077] From the above analysis, it can be found that the voltage between the lip of the hemispherical resonator 1 and the flat electrode 3 will produce a force effect on the hemispherical resonator 1, thereby affecting the stiffness. Moreover, due to the introduction of the adjustment resistor, the resistance of the X-axis and the Y-axis are inconsistent, which will cause the voltage to be unbalanced. The voltage imbalance leads to inconsistent effects on the stiffness. Therefore, the present invention achieves the effect of adjusting the stiffness by controlling the resistance value.

[0078] Specific implementation method 2: Combination Figure 1-Figure 5 This embodiment describes a system for adjusting the uneven damping and stiffness of a hemispherical resonator gyroscope, including a memory, a processor, and a computer program stored in the memory and executable on the processor. When the processor executes the computer program, any step of a method for adjusting the uneven damping and stiffness of a hemispherical resonator gyroscope is implemented.

Claims

1. A method for adjusting the uneven damping and stiffness of a hemispherical resonant gyroscope, characterized by: It includes the following steps: S1. Perform metallization coating treatment on the inner surface, support rod and lip edge of the hemispherical resonator respectively; S2, setting the angle between the large stiffness axis and the small damping axis of the hemispherical resonator after metallization coating treatment to be less than 45°; S3. Divide the electrode plate on the flat electrode into a detection electrode and a driving electrode, connect the detection electrode to the adjustment resistor, and ground the other end of the adjustment resistor; S4, setting the hemispherical resonator to a second-order four-antinode resonance state; S5. When the detection electrode detects the vibration signal of the hemispherical resonator, the detection system of the hemispherical resonator gyroscope inputs the vibration signal into the control system for demodulation and identification to obtain the damping unevenness error and stiffness deviation; S6. Adjust the resistance of the adjustment resistor according to the damping uneven error, and use the resistance of the adjustment resistor to adjust the damping and stiffness uneven errors of the hemispherical resonator.

2. The method for adjusting the uneven damping and stiffness of a hemispherical resonator gyroscope according to claim 1, characterized in that: In said S2, the angle between the large stiffness axis and the small damping axis of the hemispherical resonator after the metallized coating treatment is set to be less than 45°, and the specific process is as follows: The hemispherical resonator treated with metallized coating is adjusted by a mechanical adjustment method, and the angle between the large stiffness axis and the small damping axis of the adjusted hemispherical resonator is less than 45 degrees.

3. The method for adjusting the uneven damping and stiffness of a hemispherical resonator gyroscope according to claim 2, characterized in that: The mechanical trimming method is an ion beam method.

4. The method for adjusting the uneven damping and stiffness of a hemispherical resonator gyroscope according to claim 3, characterized in that: In the S3 , the detection electrode and the adjustment resistor are connected in parallel.

5. The method for adjusting the uneven damping and stiffness of a hemispherical resonator gyroscope according to claim 4, characterized in that: In S3, the electrode plate on the flat electrode is divided into a detection electrode and a driving electrode, the detection electrode is connected to the adjustment resistor, and the other end of the adjustment resistor is grounded. The specific process is as follows: For a hemispherical resonant gyroscope adopting a time-division multiplexing control scheme, the detection electrode is connected to the adjustment resistor through a multiplexing switch; for a hemispherical resonant gyroscope not adopting a time-division multiplexing control scheme, the detection electrode is directly connected to the adjustment resistor.

6. The method for adjusting the uneven damping and stiffness of a hemispherical resonator gyroscope according to claim 5, characterized in that: In S4, the hemispherical resonator gyroscope is installed, and the hemispherical resonator is set to a second-order four-antinode vibration mode resonance state. The specific process is as follows: A high voltage is applied to the surface of the installed hemispherical resonator, and an excitation voltage signal is applied to the driving electrode to drive the hemispherical resonator into a second-order four-antinode vibration mode resonance state.

7. The method for adjusting the uneven damping and stiffness of a hemispherical resonator gyroscope according to claim 6, characterized in that: In S5, when the detection electrode detects the vibration signal of the hemispherical resonator, the detection system of the hemispherical resonator gyroscope inputs the vibration signal into the control system for demodulation and identification, and obtains the damping unevenness error and stiffness deviation. The specific process is as follows: When the detection electrode detects the vibration signal of the hemispherical resonator, the detection system of the hemispherical resonator gyroscope inputs the vibration signal into the control system. The control system demodulates the vibration signal using the averaging method according to the second-order vibration dynamics model of the hemispherical resonator gyroscope, and then uses the least squares method or extended Kalman filter to identify the damping of the X-axis, the damping of the Y-axis, the damping unevenness error, the stiffness deviation, and the frequency decomposition.

8. The method for adjusting the uneven damping and stiffness of a hemispherical resonator gyroscope according to claim 7, characterized in that: The second-order vibration dynamics model of the hemispherical resonant gyroscope is: Where M represents the equivalent mass of the model; Indicates vibration acceleration; represents the vibration rate; C represents the equivalent damping; coefficient ε and ε0 are dielectric constants; d0 represents the distance between the lip and the plate at rest; A represents the effective area; R xi Indicates the resistance value of the X detection circuit adjustment resistor; R yi Indicates the resistance value of the Y detection circuit adjustment resistor; u E represents the DC high voltage applied to the surface of the hemispherical resonator after metallization coating; x, y represent the vibration displacement.

9. The method for adjusting the uneven damping and stiffness of a hemispherical resonator gyroscope according to claim 8, characterized in that: In S6, the resistance of the regulating resistor is adjusted according to the damping uneven error, and then the damping and stiffness uneven errors of the hemispherical resonator are adjusted using the resistance of the regulating resistor. The specific process is as follows: The damping of the X-axis is C(x), the damping of the Y-axis is C(y), the damping unevenness error is ΔC, and the stiffness deviation is ΔK; Adjust the regulating resistor R of the X detection circuit according to the damping uneven error ΔC xi And the adjustment resistor R of the Y detection circuit yi Resistance value: If C(x)-C(y)>0, then ΔR=R xi -R yi ; If C(x)-C(y)<0, then ΔR=R yi -R xi ; Adjustment resistor R after trimming xi ,R yi The resistance value satisfies: The adjustment amount of stiffness deviation is: Among them, ΔK≥ΔK′.

10. A system for adjusting the uneven damping and stiffness of a hemispherical resonant gyroscope, comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein: When the processor executes the computer program, the steps of the method according to any one of claims 1 to 9 are implemented.

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