Hemispherical resonator rigid axis identification device and method based on double-channel test

Abstract

The application provides a device and method for identifying rigid axis of hemispherical resonator based on double-channel test, which comprises a vacuum system, a hemispherical resonator fixing platform and a platform self-rotation mechanism, a resonator excitation mechanism and Doppler laser vibration meters I and II; the vacuum system comprises a vacuum chamber, a composite vacuum gauge, a dry pump-molecular pump combined pump group system and a vibration isolation platform; the hemispherical resonator fixing platform and the platform self-rotation mechanism comprise a resonator fixing station, a station fixing platform and a platform self-rotation mechanism; the rotation operation of the station fixing platform is realized through the platform self-rotation mechanism; 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 for limiting the movement of the knocking hammer; the Doppler laser vibration meters I and II are used for detecting the vibration speed of the hemispherical resonator after excitation. The application can solve the technical problem of low identification efficiency of the rigid axis of the hemispherical resonator in the prior art.

Description

TECHNICAL FIELD

[0001] The present application belongs to the technical field of hemispherical resonator gyroscopes, and particularly relates to a hemispherical resonator rigid axis identification device and method based on double-channel testing. BACKGROUND

[0002] A hemispherical resonator gyroscope is a kind of vibration gyroscope that utilizes the precession effect of the lip vibration standing wave of a hemispherical resonator along the ring direction to sense the rotation of a base, and has the advantages of high precision, long service life, small size, simple structure, etc., and has broad application prospects in military and civilian fields, and has become a hot spot in the research and application of inertial technology.

[0003] The frequency difference of a hemispherical resonator refers to the difference between the two eigenfrequency axes of the hemispherical resonator under the working mode, and the position of the two eigenfrequency axes is called the rigid axis. When there is a frequency difference, an additional orthogonal control signal is needed to suppress it, which is the main factor affecting the control accuracy of the gyroscope. Therefore, the frequency difference needs to be adjusted, and before adjustment, the position of the rigid axis needs to be accurately determined.

[0004] The hemispherical resonator needs to be in a high vacuum environment when it is working normally, and the rigid axis identification needs to be fitted by vibration attenuation data. In general, data of multiple beat frequency time lengths need to be tested, and then angle fitting is performed to obtain the position of the rigid axis, and the identification efficiency is low. SUMMARY

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

[0006] According to an aspect of the present application, a hemispherical resonator rigid axis identification device based on double-channel testing is provided, which comprises a vacuum system, a hemispherical resonator fixing platform and a platform self-rotation mechanism, a resonator excitation mechanism, and Doppler laser vibration meters I and II. The vacuum system is used to provide a vacuum environment for the testing of the hemispherical resonator. The hemispherical resonator fixing platform and the platform self-rotation mechanism comprise a resonator fixing station, a station fixing platform, and a platform self-rotation mechanism. The resonator fixing station is used to fix the hemispherical resonator to be tested, and the resonator fixing station is located on the station fixing platform. The station fixing platform is connected in the vacuum system through the platform self-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 vibration meters I and II are used to detect the vibration speed of the hemispherical resonator after excitation.

[0007] Further, the measuring points of the Doppler laser vibration meters I and II are arranged at an included angle.

[0008] Further, the vacuum system comprises a vacuum chamber, a compound vacuum gauge and a dry pump-molecular pump combination pump group system; the compound vacuum gauge and the dry pump-molecular pump combination pump group system are used for detecting and obtaining the vacuum degree of the vacuum chamber.

[0009] Further, the rigidity axis identification device for a hemispherical resonator based on double-channel testing further comprises a vibration isolation platform, and the vacuum chamber is placed on the vibration isolation platform, and the vibration isolation platform is used for isolating external vibration.

[0010] According to another aspect of the present application, a rigidity axis identification method for a hemispherical resonator based on double-channel testing is provided, which is used for quickly identifying the rigidity axis of the hemispherical resonator by using the rigidity axis identification device for a hemispherical resonator based on double-channel testing as described above.

[0011] Further, the rigidity axis identification method for a hemispherical resonator based on double-channel testing comprises:

[0012] rotating the hemispherical resonator to be tested to a position to be excited by using the platform;

[0013] driving the knocking hammer to excite the hemispherical resonator to be tested by using the rotating electromagnet excitation module;

[0014] the Doppler laser vibration tester I and the Doppler laser vibration tester II are used for detecting the vibration of the hemispherical resonator along the lip;

[0015] Firstly, the Doppler laser vibration tester I is at 0 degree, 90 degree, 180 degree or 270 degree with the position to be excited, and the vibration obtained by the Doppler laser vibration tester I and the Doppler laser vibration tester II satisfies

[0016]

[0017]

[0018] δθ=θ+θ0

[0019] wherein y(t) LVI and y(t) LVII are respectively the vibration signals measured by the Doppler laser vibration tester I and the Doppler laser vibration tester 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 included angle between the excitation position of the resonator and the rigidity axis, ω1 and ω2 respectively represent the resonant frequencies of the two working modes of the hemispherical resonator, the frequency difference is the difference between the resonant frequencies of the two working modes, and θ0 is the included angle between the measuring point of the Doppler laser vibration tester I and the measuring point of the Doppler laser vibration tester II based on the hemispherical resonator sphere.

[0020] When the vibration phases of the two working modes are 180°, the vibration signals obtained by the Doppler laser vibration tester I and the Doppler laser vibration tester II are respectively:

[0021]

[0022] Where 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 excitation position of the harmonic oscillator and the rigid axis;

[0024] The position of the rigid axis of the hemispherical harmonic oscillator is obtained by the angle θ between the excitation position of the harmonic oscillator and the rigid axis.

[0025] Furthermore, time point t1 is obtained based on the minimum value of the absolute value of the vibration signal envelope received by the two Doppler vibration meters.

[0026] The present invention provides a device and method for identifying the rigid axis of a hemispherical resonator based on dual-channel testing. This device utilizes a dual-Doppler laser vibrometer, with two Doppler measurements performed simultaneously without rotating the hemispherical resonator. The rigid axis position of the hemispherical resonator can be rapidly identified in less than the time required for one vibration beat frequency, thus improving the accuracy and efficiency of rigid axis identification for hemispherical resonator gyroscopes. Compared with existing technologies, the present invention solves the problem of low rigid axis identification efficiency for hemispherical resonators in existing technologies. Attached Figure Description

[0027] The accompanying drawings, which form part of this specification, are provided to further illustrate embodiments of the invention and, together with the textual description, explain the principles of the invention. It is obvious that the drawings described below are merely some embodiments of the invention, and those skilled in the art can obtain other drawings based on these drawings without any creative effort.

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

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

[0030] 1. Vacuum chamber; 2. Composite vacuum gauge; 3. Dry pump-molecular pump combined pump system; 4. Vibration isolation platform; 5. Resonator fixed station; 6. Station fixed platform; 7. Platform rotation mechanism; 8. Hemispherical resonator; 9. Electromagnetic excitation module; 10. Striking hammer; 11. Limiting groove; 12. Doppler laser vibration meter I; 13. Doppler laser vibration meter II. Detailed Implementation

[0031] It should be noted that, unless otherwise specified, the embodiments and features described in this application can be combined with each other. The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of them. The following description of at least one exemplary embodiment is merely illustrative and is in no way intended to limit the present invention or its application or use. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0032] It should be noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the exemplary embodiments according to this application. As used herein, the singular form is intended to include the plural form as well, unless the context clearly indicates otherwise. Furthermore, it should be understood that when the terms "comprising" and / or "including" are used in this specification, they indicate the presence of features, steps, operations, devices, components, and / or combinations thereof.

[0033] Unless otherwise specifically stated, the relative arrangement, numerical expressions, and values ​​of the components and steps described in these embodiments do not limit the scope of the invention. It should also be understood that, for ease of description, the dimensions of the various parts shown in the accompanying drawings are not drawn to actual scale. Techniques, methods, and devices known to those skilled in the art may not be discussed in detail, but where appropriate, such techniques, methods, and devices should be considered part of the specification. In all examples shown and discussed herein, any specific values ​​should be interpreted as merely exemplary and not as limitations. 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 rigid axis identification device for a hemispherical harmonic oscillator based on dual-channel testing is provided. The device includes:

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

[0036] The vacuum system includes a vacuum chamber 1, a composite vacuum gauge 2, a dry pump-molecular pump combination system 3, and a vibration isolation platform 4. The composite vacuum gauge 2 and the dry pump-molecular pump combination system 3 are used to acquire and detect the vacuum level of the vacuum chamber 1. The vacuum chamber 1 is placed on the vibration isolation platform 4, which 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 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 inside the vacuum chamber 1 are connected through the platform rotation mechanism 7. The platform rotation mechanism can realize the rotation operation of the station fixing platform 6.

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

[0039] Doppler laser vibrometer I12 and Doppler laser vibrometer II13 are used to detect the vibration velocity of the excited hemispherical harmonic oscillator 8.

[0040] This configuration provides a rigid axis identification device for a hemispherical resonator based on dual-channel testing. The device uses a dual-Doppler laser vibrometer, which performs simultaneous measurements with two Dopplers without rotating the hemispherical resonator. It can quickly identify the rigid axis position of the hemispherical resonator in less than the time required for one vibration beat frequency, thus improving the accuracy and efficiency of rigid axis identification for hemispherical resonator gyroscopes.

[0041] As a specific embodiment of the present invention, the measuring points of the Doppler laser vibrometer I12 and the Doppler laser vibrometer II13 are set at an angle.

[0042] According to another aspect of the present invention, a method for identifying the rigid axis of a hemispherical harmonic oscillator based on dual-channel testing is provided. This method employs the aforementioned dual-channel testing-based rigid axis identification device for hemispherical harmonic oscillators to achieve rapid identification of the rigid axis of the hemispherical harmonic oscillator. The method specifically includes:

[0043] The hemispherical resonator 8 under test is rotated to the position to be excited by the platform. The hammer 10 is driven by the rotating electromagnet excitation module 9 to excite the hemispherical resonator 8 under test. The vibration of the lip of the hemispherical resonator is detected by Doppler laser vibrometer I12 and Doppler laser vibrometer II13.

[0044] In this case, the Doppler laser vibration meter I12 is at an angle of 0 degrees, 90 degrees, 180 degrees, or 270 degrees to the excitation position. At this angle, the vibration measured by the Doppler laser vibration meter satisfies the following form:

[0045]

[0046]

[0047] δθ=θ+θ0

[0048] Where, y(t) LVI and y(t) LVII The vibration signals measured by Doppler laser vibrometers I12 and II13 are respectively. τ is the decay time constant of the hemispherical harmonic oscillator, which is related to the frequency and quality factor of the harmonic oscillator; A is the initial amplitude of the working mode at the excitation point of the harmonic oscillator; θ is the angle between the excitation position of the harmonic oscillator and the rigid axis; ω1 and ω2 represent the resonant frequencies of the two working modes of the hemispherical harmonic oscillator, respectively, and the frequency difference is the difference between the resonant frequencies of the two working modes; θ0 is the angle between the measuring points of Doppler laser vibrometer I12 and Doppler laser vibrometer II13 based on the spherical surface of the hemispherical harmonic oscillator; t is time.

[0049] At the start of excitation, the vibrations on the two rigid shafts are in phase. Due to the frequency difference, the vibrations of the two working modes will have a phase difference in subsequent vibrations. After a period of vibration, when the phase difference between the two working modes is 180°, the vibration signals from the two Doppler laser vibrometers are as follows:

[0050]

[0051] In the formula, t1 is the time point when the phase difference between the two working modes is 180°, and the absolute value of the envelope of the vibration signals received by the two Doppler vibration meters is also at its minimum at this time point. Therefore, this time point can be found relatively easily from the Doppler vibration meter signals. The ratio of the two vibration signals is...

[0052]

[0053] In the formula, y(t1) LVI ,y(t2) LVII Let the signal amplitudes of the two Doppler laser vibrometers be known quantities, and θ be calculated using the above formula. Therefore, without measuring the full beat frequency, the specific location of the rigid shaft can be determined by comparing signals over a short period.

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

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

[0056] (1) The rigid shaft identification device and method of the hemispherical harmonic oscillator based on dual-channel testing of the present invention can quickly identify the position of the rigid shaft of the hemispherical harmonic oscillator in less than one vibration beat frequency, which greatly improves the testing efficiency.

[0057] (2) The rigid shaft identification device and method of hemispherical harmonic oscillator based on dual-channel testing of the present invention uses a dual-Doppler laser vibrometer. The two Dopplers are measured synchronously and there is no need to rotate the hemispherical harmonic oscillator, which improves the accuracy of the vibration signal of the hemispherical harmonic oscillator.

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

[0059] Furthermore, it should be noted that the use of terms such as "first" and "second" to define components is merely for the purpose of distinguishing the corresponding components. Unless otherwise stated, the above terms have no special meaning and therefore should not be construed as limiting the scope of protection of this invention.

[0060] The above are merely preferred embodiments of the present invention and are not intended to limit the present invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A method for identifying the rigid axis of a hemispherical harmonic oscillator based on dual-channel testing, characterized in that, The method for identifying the rigid axis of a hemispherical harmonic oscillator based on dual-channel testing includes: The hemispherical harmonic oscillator (8) to be tested is rotated to the position to be excited by the platform; The hammer (10) is driven by the rotating electromagnet excitation module (9) to excite the hemispherical harmonic oscillator (8) under test. Doppler laser vibrometer I (12) and Doppler laser vibrometer II (13) were used to detect the vibration of the lip of the hemispherical harmonic oscillator: First, the Doppler laser vibration meter I (12) is at an angle of 0 degrees, 90 degrees, 180 degrees, or 270 degrees to the excitation position. The vibrations obtained by the Doppler laser vibration meter I (12) and the Doppler laser vibration meter II (13) satisfy the following: δθ=θ+θ0 Where, y(t) LVΙ and y(t) LVΙΙ The vibration signals measured by Doppler laser vibrometer I (12) and Doppler laser vibrometer II (13) at time t are respectively, where τ is the decay time constant of the hemispherical harmonic oscillator; A is the initial amplitude of the working mode at the excitation point of the harmonic oscillator; θ is the angle between the excitation position of the harmonic oscillator and the rigid axis; ω1 and ω2 represent the resonant frequencies of the two working modes of the hemispherical harmonic oscillator, respectively, and the frequency difference is the difference between the resonant frequencies of the two working modes; θ0 is the angle between the measuring points of Doppler laser vibrometer I (12) and Doppler laser vibrometer II (13) on the spherical surface of the hemispherical harmonic oscillator. When the vibration phases of the two working modes differ by 180°, the vibration signals obtained by Doppler laser vibrometer I (12) and Doppler laser vibrometer II (13) are as follows: Where t1 is the time point when the phase difference between the two working modes is 180°; according to Obtain the angle θ between the excitation position of the harmonic oscillator and the rigid axis; The position of the rigid axis of the hemispherical harmonic oscillator is obtained by the angle θ between the excitation position of the harmonic oscillator and the rigid axis. The hemispherical harmonic oscillator rigid axis identification method based on dual-channel testing uses a hemispherical harmonic oscillator rigid axis identification device based on dual-channel testing to achieve rapid identification of the rigid axis of the hemispherical harmonic oscillator. The hemispherical harmonic oscillator rigid axis identification device based on dual-channel testing includes: a vacuum system, a hemispherical harmonic oscillator fixed platform and platform rotation mechanism, a harmonic oscillator 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 harmonic oscillator; The hemispherical resonator fixing platform and 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), and the station fixing platform (6) is connected to the vacuum system through the platform rotation mechanism (7) to realize the rotation of the station fixing platform (6); The resonator excitation mechanism includes a rotating electromagnet excitation module (9), a hammer (10), and a limiting groove (11); the rotating electromagnet excitation module (9) provides excitation to the hammer (10), and the limiting groove (11) is used to limit the movement of the hammer (10); The Doppler laser vibrometer I (12) and the Doppler laser vibrometer II (13) are used to detect the vibration velocity of the excited hemispherical harmonic oscillator (8).

2. The method for identifying the rigid axis of a hemispherical harmonic oscillator based on dual-channel testing according to claim 1, characterized in that, The time point t1 is obtained based on the minimum value of the absolute value of the envelope of the vibration signals received by the two Doppler vibration meters.

3. The method for identifying the rigid axis of a hemispherical harmonic oscillator based on dual-channel testing according to claim 1, characterized in that, The measuring points of Doppler laser vibration meter I (12) and Doppler laser vibration meter II (13) are set at an angle.

4. The method for identifying the rigid axis of a hemispherical harmonic oscillator based on dual-channel testing according to claim 1, characterized in that, The vacuum system includes a vacuum chamber (1), a composite vacuum gauge (2), and a dry pump-molecular pump combination system (3); the composite vacuum gauge (2) and the dry pump-molecular pump combination system (3) are used to detect and obtain the vacuum level of the vacuum chamber (1).

5. The method for identifying the rigid axis of a hemispherical harmonic oscillator based on dual-channel testing according to claim 4, characterized in that, The rigid shaft identification device for a hemispherical harmonic oscillator based on dual-channel testing also includes a vibration isolation platform (4), on which the vacuum chamber (1) is placed. The vibration isolation platform (4) is used to isolate external vibrations.

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