Hemispherical harmonic oscillator rigid shaft identification device and method based on dual-channel test

Abstract

The invention provides a hemispherical harmonic oscillator rigid axis identification device and method based on double-channel testing. The device comprises a vacuum system, a hemispherical harmonic oscillator fixing platform, a platform rotation mechanism, a harmonic oscillator excitation mechanism, a Doppler laser vibration meter I and a Doppler laser vibration meter II. The vacuum system comprises a vacuum chamber, a composite vacuum gauge, a dry pump-molecular pump combined pump set system and a vibration isolation platform; the hemispherical harmonic oscillator fixing platform and platform autorotation mechanism comprises a harmonic oscillator fixing station, a station fixing platform and a platform autorotation mechanism; the rotating operation of the station fixing platform is realized through the platform autorotation mechanism; the harmonic oscillator excitation mechanism comprises a rotary electromagnet excitation module, a knocking hammer and a limiting groove; the rotary electromagnet excitation module provides excitation for the knocking hammer, and the limiting groove is used for limiting movement of the knocking hammer. And the Doppler laser vibration meters I and II are used for detecting the vibration speed of the excited hemispherical harmonic oscillator. The technical problem of low identification efficiency of the rigid shaft of the hemispherical harmonic oscillator in the prior art can be solved.

Description

Technical Field

[0001] The invention belongs to the technical field of hemispherical resonator gyroscopes, and in particular relates to a hemispherical resonator rigid axis identification device and method based on dual-channel testing. Background Art

[0002] The hemispherical resonator gyroscope is a vibrating gyroscope that utilizes the precession effect of the lip vibration standing wave of the hemispherical resonator to rotate the sensitive base. It has the advantages of high precision, long life, small size and simple structure. It has broad application prospects in both military and civilian fields and has become a hot spot in the research and application of inertial technology.

[0003] The frequency difference of the hemispherical resonator refers to the difference between the resonant frequencies of the two eigen-axis in the working mode of the hemispherical resonator. The position of the two eigen-frequency axes is called the rigid axis. When there is a frequency difference, it needs to be suppressed by an additional orthogonal control signal. It is the main factor affecting the control accuracy of the gyroscope. Therefore, the frequency difference needs to be adjusted. Before adjusting, the position of the rigid axis needs to be accurately determined.

[0004] The hemispherical resonator needs to be in a high vacuum environment when working normally. The rigid axis identification needs to be done by fitting the vibration attenuation data. Usually, it is necessary to test the data of multiple beat frequency time lengths and then perform angle fitting to obtain the rigid axis position. The identification efficiency is low. Summary of the invention

[0005] The present invention aims to solve at least one of the technical problems existing in the prior art.

[0006] According to one aspect of the present invention, a hemispherical resonator rigid axis identification device based on dual-channel testing is provided, and the hemispherical resonator rigid axis identification device based on dual-channel testing comprises: a vacuum system, a hemispherical resonator fixing platform and a platform rotation mechanism, a resonator excitation mechanism and Doppler laser vibrometers I and II; the vacuum system is used to provide a vacuum environment for the test of the hemispherical resonator; the hemispherical resonator fixing platform and the platform rotation mechanism comprise a resonator fixing station, a station fixing platform and a platform rotation mechanism; the resonator fixing station is used to fix the hemispherical resonator to be tested, the resonator fixing station is located on the station fixing platform, and the station fixing platform is connected to the vacuum system through the platform rotation mechanism to realize the rotation of the station fixing platform; the resonator excitation mechanism comprises a rotating electromagnet excitation module, a knocking hammer and a limiting groove; the rotating electromagnet excitation module provides excitation for the knocking hammer, and the limiting groove is used to limit the movement of the knocking hammer; the Doppler laser vibrometer I and the Doppler laser vibrometer II are used to detect the vibration speed of the hemispherical resonator after excitation.

[0007] Furthermore, the measuring points of the Doppler laser vibrometer I and the Doppler laser vibrometer II are arranged at an angle.

[0008] Furthermore, the vacuum system includes a vacuum chamber, a compound vacuum gauge and a dry pump-molecular pump combination pump system; the compound vacuum gauge and the dry pump-molecular pump combination pump system are used to detect and obtain the vacuum degree of the vacuum chamber.

[0009] Furthermore, the hemispherical resonator rigid axis identification device based on dual-channel testing also includes a vibration isolation platform, the vacuum chamber is placed on the vibration isolation platform, and the vibration isolation platform is used to isolate external vibrations.

[0010] According to another aspect of the present invention, a method for identifying a rigid axis of a hemispherical resonator based on dual-channel testing is provided. The method uses the hemispherical resonator rigid axis identification device based on dual-channel testing as described above to realize rapid identification of the rigid axis of a hemispherical resonator.

[0011] Furthermore, the hemispherical resonator rigid axis identification method based on dual-channel testing includes:

[0012] The hemispherical resonator to be tested is rotated to the position to be excited through the platform;

[0013] The rotating electromagnet excitation module drives the hammer to excite the hemispherical resonator to be tested;

[0014] Doppler laser vibrometer I and Doppler laser vibrometer II detect the vibration of the lip edge of the hemispherical resonator:

[0015] First, the Doppler laser vibrometer I is 0 degrees, 90 degrees, 180 degrees, or 270 degrees to the excitation position. The vibrations measured by the Doppler laser vibrometer I and the Doppler laser vibrometer II meet the following requirements:

[0016]

[0017]

[0018] δθ=θ+θ0

[0019] Among them, y(t) LVI and y(t) LVII are the vibration signals measured by Doppler laser vibrometer I and Doppler laser vibrometer II at time t, τ is the decay time constant of the hemispherical resonator; A is the initial amplitude of the working mode at the excitation position of the resonator, θ is the angle between the excitation position of the resonator and the rigid axis; ω1 and ω2 represent the resonant frequencies of the two working modes of the hemispherical resonator, and the frequency difference is the difference between the resonant frequencies of the two working modes; θ0 is the angle between the measuring point of Doppler laser vibrometer I and the measuring point of Doppler laser vibrometer II based on the spherical surface of the hemispherical resonator;

[0020] When the vibration phase difference between the two working modes is 180°, the vibration signals obtained by the Doppler laser vibrometer I and Doppler laser vibrometer II are:

[0021]

[0022] Among them, t1 is the time point when the phase difference between the two working modes is 180°;

[0023] according to Obtain the angle θ between the resonator excitation position and the rigid axis;

[0024] The rigid axis position of the hemispherical resonator is obtained according to the angle θ between the resonator excitation position and the rigid axis.

[0025] Furthermore, the time point t1 is obtained according to the minimum value of the absolute value of the vibration signal envelope received by the two Doppler vibrometers.

[0026] By applying the technical solution of the present invention, a device and method for identifying the rigid axis of a hemispherical resonator based on dual-channel testing are provided. The device for identifying the rigid axis of a hemispherical resonator uses a dual-Doppler laser vibrometer. Two Dopplers are measured synchronously without rotating the hemispherical resonator. The rigid axis position of the hemispherical resonator can be quickly identified in less than a vibration beat frequency, thereby improving the rigid axis identification accuracy and efficiency of the hemispherical resonator gyroscope. Compared with the prior art, the technical solution of the present invention can solve the technical problem of low rigid axis identification efficiency of the hemispherical resonator in the prior art. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] The included drawings are used to provide a further understanding of the embodiments of the present invention, which constitute a part of the specification, are used to illustrate the embodiments of the present invention, and together with the text description, explain the principles of the present invention. Obviously, the drawings in the following description are only some embodiments of the present invention, and for ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0028] Figure 1 A schematic structural diagram of a hemispherical resonator rigid axis identification device based on dual-channel testing provided according to a specific embodiment of the present invention is shown.

[0029] The above drawings include the following reference numerals:

[0030] 1. Vacuum chamber, 2. Compound vacuum gauge, 3. Dry pump-molecular pump combination pump system, 4. Seismic isolation platform, 5. Resonator fixed station, 6. Station fixed platform, 7. Platform rotation mechanism, 8. Hemispherical resonator, 9. Electromagnetic excitation module, 10. Percussion hammer, 11. Limiting groove, 12. Doppler laser vibrometer I, 13. Doppler laser vibrometer II. DETAILED DESCRIPTION

[0031] It should be noted that, in the absence of conflict, the embodiments in this application and the features in the embodiments can be combined with each other. The technical solutions 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. The following description of at least one exemplary embodiment is actually only illustrative and is by no means intended to limit the present invention and its application or use. Based on the embodiments in the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0032] It should be noted that the terms used herein are only for describing specific embodiments and are not intended to limit the exemplary embodiments according to the present application. As used herein, unless the context clearly indicates otherwise, the singular form is also intended to include the plural form. In addition, it should be understood that when the terms "comprise" and / or "include" are used in this specification, it indicates the presence of features, steps, operations, devices, components and / or combinations thereof.

[0033] Unless otherwise specifically stated, the relative arrangement, numerical expressions and numerical values ​​of the parts and steps set forth in these embodiments do not limit the scope of the present invention. At the same time, it should be understood that, for ease of description, the sizes of the various parts shown in the accompanying drawings are not drawn according to actual proportional relationships. The technology, methods and equipment known to those of ordinary skill in the relevant art may not be discussed in detail, but in appropriate cases, the technology, methods and equipment should be considered as a part of the specification. In all examples shown and discussed here, any specific value should be interpreted as being merely exemplary, rather than as a limitation. Therefore, other examples of exemplary embodiments may have different values.

[0034] like Figure 1 As shown, according to a specific embodiment of the present invention, a hemispherical resonator rigid axis identification device based on dual-channel testing is provided, and the device includes:

[0035] Vacuum system, hemispherical resonator fixing platform and platform rotation mechanism, resonator excitation mechanism and Doppler laser vibrometers I and II, vibration isolation platform 4;

[0036] The vacuum system includes a vacuum chamber 1, a compound vacuum gauge 2, a dry pump-molecular pump combination pump system 3 and a vibration isolation platform 4; the compound vacuum gauge 2 and the dry pump-molecular pump combination pump system 3 are used to obtain and detect the vacuum degree of the vacuum chamber 1; the vacuum chamber 1 is placed on the vibration isolation platform 4, and the vibration isolation platform 4 is used to isolate external vibrations so that the system can always be in a stable and excellent working state;

[0037] The hemispherical resonator fixing platform and the platform rotation mechanism include a resonator fixing station 5, a station fixing platform 6 and a platform rotation mechanism 7; the resonator fixing station 5 is used to fix the hemispherical resonator 8 to be tested, the resonator fixing station 5 is located on the station fixing platform 6, the station fixing platform 6 and the bottom surface of the vacuum chamber 1 are connected through the platform rotation mechanism 7, and the rotation operation of the station fixing platform 6 can be realized through the platform rotation mechanism;

[0038] The resonator excitation mechanism includes a rotating electromagnet excitation module 9, a percussion hammer 10 and a limiting slot 11; the rotating electromagnet excitation module 9 provides excitation for the percussion hammer 10, and the limiting slot 11 is used to limit the movement of the percussion hammer 10;

[0039] The Doppler laser vibrometer I 12 and the Doppler laser vibrometer II 13 are used to detect the vibration speed of the hemispherical resonator 8 after excitation.

[0040] By applying this configuration, a hemispherical resonator rigid axis identification device based on dual-channel testing is provided. The hemispherical resonator rigid axis identification device uses a dual-Doppler laser vibrometer. Two Dopplers are measured synchronously without rotating the hemispherical resonator. The rigid axis position of the hemispherical resonator can be quickly identified in less than a vibration beat frequency, thereby improving the rigid axis identification accuracy and efficiency of the hemispherical resonator gyroscope.

[0041] As a specific embodiment of the present invention, the measuring points of the Doppler laser vibrometer I 12 and the Doppler laser vibrometer II 13 are arranged at an angle.

[0042] According to another aspect of the present invention, a method for identifying a rigid axis of a hemispherical resonator based on dual-channel testing is provided. The method uses the above-mentioned device for identifying a rigid axis of a hemispherical resonator based on dual-channel testing to realize rapid identification of the rigid axis of the hemispherical resonator. The method specifically comprises:

[0043] The hemispherical resonator 8 to be tested is rotated to the position to be excited through the platform, and the hammer 10 is driven by the rotating electromagnet excitation module 9 to excite the hemispherical resonator 8 to be tested, and the vibration of the lip edge of the hemispherical resonator is detected by using the Doppler laser vibrometer I12 and the Doppler laser vibrometer II 13;

[0044] The Doppler laser vibrometer I12 is 0 degrees, 90 degrees, 180 degrees, or 270 degrees to the excitation position. At this time, the vibration obtained by the Doppler laser vibrometer test satisfies the following form:

[0045]

[0046]

[0047] δθ=θ+θ0

[0048] Among them, y(t) LVI and y(t) LVII are the vibration signals measured by Doppler laser vibrometer I12 and Doppler laser vibrometer II 13 respectively, τ is the decay time constant of the hemispherical resonator, which is related to the frequency and quality factor of the resonator; A is the initial amplitude of the working mode at the excitation position of the resonator, θ is the angle between the excitation position of the resonator and the rigid axis; ω1 and ω2 represent the resonant frequencies of the two working modes of the hemispherical resonator respectively, and the frequency difference is the difference between the resonant frequencies of the two working modes; θ0 is the angle between the measuring point of Doppler laser vibrometer I12 and the measuring point of Doppler laser vibrometer II 13 based on the spherical surface of the hemispherical resonator; t is time.

[0049] At the beginning of the excitation, the vibration phases on the two rigid axes are the same. Due to the frequency difference, the vibrations of the two working modes will have a phase difference in the subsequent vibrations. After a period of vibration, when the vibration phase difference of the two working modes is 180°, the vibration signals of the two Doppler laser vibrometers are:

[0050]

[0051] In the formula, t1 is the time point when the phase difference between the two working modes is 180°. The absolute value of the vibration signal envelope received by the two Doppler vibrometers is also at its minimum at this time point. Therefore, it is relatively easy to find this time point from the Doppler vibrometer signal. The ratio of the two vibration signals is

[0052]

[0053] In the formula, y(t1) LVI , y(t2) LVII is the signal amplitude of the two Doppler laser vibrometers, which is a known quantity, and θ can be calculated by the above formula. Therefore, there is no need to measure the complete beat frequency, and the specific position of the rigid shaft can be calculated by comparing the signals in a shorter time.

[0054] The vibration performance test of the hemispherical resonator of the present invention adopts a method of single-point hammer excitation and dual-path laser vibrometer detection. By using a dual-Doppler laser tester, the rigid axis position of the hemispherical resonator can be determined in a short time of less than one beat frequency, laying a solid foundation for the subsequent rapid adjustment and engineering of the hemispherical resonator.

[0055] The beneficial effects of the present invention compared with the prior art are as follows:

[0056] (1) The device and method for identifying the rigid axis of a hemispherical resonator based on dual-channel testing of the present invention can realize rapid identification of the rigid axis position of the hemispherical resonator in less than one vibration beat frequency, greatly improving the testing efficiency;

[0057] (2) The hemispherical resonator rigid axis identification device and method based on dual-channel testing of the present invention uses a dual-Doppler laser vibrometer, and two Dopplers are measured synchronously without rotating the hemispherical resonator, thereby improving the accuracy of the hemispherical resonator vibration signal.

[0058] For ease of description, spatially relative terms such as "above", "above", "on the upper surface of", "above", etc. may be used here to describe the spatial positional relationship between a device or feature and other devices or features as shown in the figure. It should be understood that spatially relative terms are intended to include different orientations of the device in use or operation in addition to the orientation described in the figure. For example, if the device in the accompanying drawings is inverted, the device described as "above other devices or structures" or "above other devices or structures" will be positioned as "below other devices or structures" or "below other devices or structures". Thus, the exemplary term "above" can include both "above" and "below". The device can also be positioned in other different ways (rotated 90 degrees or in other orientations), and the spatially relative descriptions used here are interpreted accordingly.

[0059] In addition, it should be noted that the use of terms such as "first" and "second" to limit components is only for the convenience of distinguishing the corresponding components. If not otherwise stated, the above terms have no special meaning and therefore cannot be understood as limiting the scope of protection of the present invention.

[0060] The above are only preferred embodiments of the present invention and are not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A hemispherical resonator rigid axis identification device based on dual-channel testing, characterized in that: The hemispherical resonator rigid axis identification device based on dual-channel testing comprises: a vacuum system, a hemispherical resonator fixing platform and a platform rotation mechanism, a resonator excitation mechanism, a Doppler laser vibrometer I (12) and a Doppler laser vibrometer II (13); The vacuum system is used to provide a vacuum environment for testing the hemispherical resonator; The hemispherical resonator fixing platform and platform self-rotation mechanism comprise a resonator fixing station (5), a station fixing platform (6) and a platform self-rotation mechanism (7); the resonator fixing station (5) is used to fix the hemispherical resonator (8) to be tested, the resonator fixing station (5) is located on the station fixing platform (6), and the station fixing platform (6) is connected to the vacuum system through the platform self-rotation mechanism (7) to realize the rotation of the station fixing platform (6); The resonator excitation mechanism comprises a rotating electromagnet excitation module (9), a striking hammer (10) and a limiting groove (11); the rotating electromagnet excitation module (9) provides excitation for the striking hammer (10), and the limiting groove (11) is used to limit the movement of the striking hammer (10); The Doppler laser vibrometer I (12) and the Doppler laser vibrometer II (13) are used to detect the vibration speed of the hemispherical resonator (8) after excitation.

2. The hemispherical resonator rigid axis identification device based on dual-channel testing according to claim 1 is characterized in that: The measuring points of the Doppler laser vibrometer I (12) and the Doppler laser vibrometer II (13) are arranged at an angle.

3. The hemispherical resonator rigid axis identification device based on dual-channel testing according to claim 1 is characterized in that: The vacuum system comprises a vacuum chamber (1), a compound vacuum gauge (2) and a dry pump-molecular pump combination pump system (3); the compound vacuum gauge (2) and the dry pump-molecular pump combination pump system (3) are used to detect and obtain the vacuum degree of the vacuum chamber (1).

4. The hemispherical resonator rigid axis identification device based on dual-channel testing according to claim 1 is characterized in that: The hemispherical resonator rigid axis identification device based on dual-channel testing also includes a vibration isolation platform (4), the vacuum chamber (1) is placed on the vibration isolation platform (4), and the vibration isolation platform (4) is used to isolate external vibrations.

5. A method for identifying the rigid axis of a hemispherical resonator based on dual-channel testing, characterized in that: The method uses the hemispherical resonator rigid axis identification device based on dual-channel testing as described in claims 1 to 4 to achieve rapid identification of the hemispherical resonator rigid axis.

6. The method for identifying the rigid axis of a hemispherical resonator based on dual-channel testing according to claim 5 is characterized in that: The hemispherical resonator rigid axis identification method based on dual-channel testing includes: The hemispherical resonator (8) to be tested is rotated to a position to be excited via the platform; The rotating electromagnet excitation module (9) drives the striking hammer (10) to excite the hemispherical resonator (8) to be tested; Doppler laser vibrometer I (12) and Doppler laser vibrometer II (13) detect the vibration of the lip edge of the hemispherical resonator: First, the Doppler laser vibrometer I (12) is 0 degrees, 90 degrees, 180 degrees, or 270 degrees to the excitation position. The vibrations measured by the Doppler laser vibrometer I (12) and the Doppler laser vibrometer II (13) satisfy: δθ=θ+θ0 Among them, y(t) LVI and y(t) LVII are the vibration signals measured by Doppler laser vibrometer I (12) and Doppler laser vibrometer II (13) at time t, τ is the decay time constant of the hemispherical resonator; A is the initial amplitude of the working mode at the excitation position of the resonator, θ is the angle between the excitation position of the resonator and the rigid axis; ω1 and ω2 represent the resonant frequencies of the two working modes of the hemispherical resonator, and the frequency difference is the difference between the resonant frequencies of the two working modes; θ0 is the angle between the measuring point of Doppler laser vibrometer I (12) and the measuring point of Doppler laser vibrometer II (13) based on the spherical surface of the hemispherical resonator; When the vibration phase difference between the two working modes is 180°, the vibration signals obtained by the Doppler laser vibrometer I (12) and the Doppler laser vibrometer II (13) are: Among them, t1 is the time point when the phase difference between the two working modes is 180°; according to Obtain the angle θ between the resonator excitation position and the rigid axis; The rigid axis position of the hemispherical resonator is obtained according to the angle θ between the resonator excitation position and the rigid axis.

7. The method for identifying the rigid axis of a hemispherical resonator based on dual-channel testing according to claim 6 is characterized in that: The time point t1 is obtained according to the minimum value of the absolute value of the vibration signal envelope received by the two Doppler vibrometers.

Images