Micromechanical nested annular gyroscope

Abstract

The invention discloses a micromechanical nested ring gyroscope. The micromechanical nested ring gyroscope comprises a substrate, a supporting structure, a nested ring resonator and a plurality of electrodes, wherein the supporting structure, the nested ring resonator and the electrodes are arranged on the substrate. The supporting structure comprises an anchor point and a flexible supporting part, the anchor point is connected with the substrate, and the flexible supporting part is connected with the anchor point and used for supporting the nested ring resonator. Due to the fact that the supporting structure with the flexible supporting component is adopted, stress conduction caused by temperature changes can be reduced. By adjusting structural parameters, the resonant frequency of the working mode of the gyroscope is optimized, and the vibration sensitivity of the gyroscope is reduced. Therefore, the problem that the performance of the micromechanical gyroscope is reduced when the micromechanical gyroscope works in a severe environment can be solved.

Description

Technical Field

[0001] The present application relates to the field of aerospace technology, and more specifically, to a micro-mechanical nested ring gyroscope. Background Art

[0002] A micromechanical gyroscope (MEMS gyroscope) is a miniature angular velocity sensor manufactured using Micro Electro Mechanical Systems (MEMS) technology. MEMS technology is a cutting-edge technology that integrates multiple disciplines such as microelectronics, microengineering mechanics, and precision mechanics. It achieves the miniaturization and integration of traditional macroscopic mechanical devices by processing micromechanical structures on silicon substrates. Micromechanical gyroscopes use Coriolis force to detect angular velocity. Specifically, there is a constantly oscillating mass block inside the gyroscope. When rotation occurs, the mass block will produce a lateral displacement due to the Coriolis force. This displacement is detected by the capacitive sensing device and converted into an electrical signal output.

[0003] As an inertial sensor that measures the angular velocity or attitude angle of an object moving in space, the micromechanical gyroscope has the advantages of small size, light weight, low power consumption, low cost, and easy integration, making it widely used in many fields such as inertial navigation systems, automobiles, consumer electronics, and mineral development. These demands provide huge space for the further development of MEMS gyroscopes, while also placing higher requirements on the performance of MEMS gyroscopes. In particular, when the micromechanical gyroscope works in a relatively harsh environment, such as when the ambient temperature changes dramatically or there is a strong vibration environment, its performance will be reduced, resulting in failure to meet the needs of the application scenario. Summary of the invention

[0004] In view of this, the present application provides a micromechanical ring-nested gyroscope to solve the problem of performance degradation of the micromechanical gyroscope when working in a harsh environment.

[0005] In order to achieve the above objectives, the proposed solution is as follows:

[0006] A micromechanical nested ring gyroscope comprises a substrate and a support structure arranged on the substrate, a nested ring resonator and a plurality of electrodes, wherein:

[0007] The support structure includes an anchor point and a flexible support component, wherein the anchor point is connected to the substrate, and the flexible support component is connected to the anchor point and is used to support the nested ring resonator.

[0008] Optionally, the support structure, the nested ring resonator and the plurality of electrodes are all made of SOI wafers with a (100) crystal plane.

[0009] Optionally, the flexible supporting component is a curved and folded flexible supporting beam.

[0010] Optionally, the nested ring resonator includes a plurality of concentrically arranged ring resonant structures.

[0011] Optionally, the wall thickness of each of the annular resonant structures is the same, and the distance between any two of the annular resonant structures is the same.

[0012] Optionally, a plurality of spoke structures are arranged between any two of the annular resonant structures.

[0013] Optionally, the wall thicknesses of any two of the spoke structures are the same.

[0014] Optionally, the two third-order wine glass-shaped degenerate modes in which the micromechanical nested ring gyroscope operates include a first mode and a second mode, wherein:

[0015] The electrodes include a plurality of first driving electrodes and first detecting electrodes for supporting the first mode, second driving electrodes and second detecting electrodes for supporting the second mode, and an anchor point electrode disposed on the anchor point for providing a bias voltage.

[0016] It can be seen from the above technical solutions that the present application discloses a micromechanical nested ring gyroscope, including a substrate and a support structure arranged on the substrate, a nested ring resonator and a plurality of electrodes. The support structure includes an anchor point and a flexible support component, the anchor point is connected to the substrate, the flexible support component is connected to the anchor point, and is used to support the nested ring resonator. Since a support structure with a flexible support component is adopted, the conduction of stress caused by temperature changes can be reduced. By adjusting the structural parameters, the resonant frequency of the gyroscope working mode is optimized, and the vibration sensitivity of the gyroscope is reduced. Thereby, the problem of performance degradation of the micromechanical gyroscope when working in a harsh environment can be solved. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0018] Figure 1 A partial schematic diagram of a micromechanical annular nested gyroscope according to an embodiment of the present application;

[0019] Figure 2 A schematic diagram of a support structure according to an embodiment of the present application;

[0020] Figure 3 The third-order wine glass mode of the micromechanical annular nested gyroscope in the embodiment of the present application;

[0021] Figure 4 The in-plane translation mode of the micro-mechanical annular nested gyroscope in the embodiment of the present application;

[0022] Figure 5 This is the out-of-plane cylindrical mode of the micromechanical annular nested gyroscope in the embodiment of the present application. DETAILED DESCRIPTION

[0023] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0024] Figure 1 A partial schematic diagram of a micromechanical ring-nested gyroscope according to an embodiment of the present application.

[0025] like Figure 1 As shown, this embodiment provides a micromechanical nested ring gyroscope, which includes a substrate and a support structure arranged on the substrate, a nested ring resonator and a plurality of electrodes, and the drive circuit is used to connect to the plurality of electrodes, output a drive signal to the corresponding electrode and obtain a detection signal, and obtain the angular velocity by processing the detection signal. The support structure, the nested ring resonator and the plurality of electrodes are all processed by SOI wafers with a (100) crystal plane.

[0026] like Figure 2 As shown, the support structure includes an anchor point 1 and a flexible support component 2, the anchor point is connected to the substrate, and the flexible support component is connected to the anchor point, and is used to support the nested ring resonator. The flexible support component is a bent and folded flexible support beam. The nested ring resonator includes a plurality of concentrically arranged ring resonant structures 3. The wall thickness of each ring resonant structure is the same, and the distance between any two of the ring resonant structures is the same. A plurality of spoke structures 4 are arranged between any two ring resonant structures.

[0027] The two third-order wine glass-shaped degenerate modes in which the micromechanical nested ring gyroscope works include a first mode and a second mode. The electrodes include a plurality of first drive electrodes and a first detection electrode for supporting the first mode, a second drive electrode and a second detection electrode for supporting the second mode, and an anchor electrode arranged on an anchor point for providing a bias voltage.

[0028] In a specific embodiment of the present application, the number of annular resonant structures is 10, the number of anchor points and flexible support beams is 8, the number of spoke structures is 16 groups, and they are evenly distributed on the circumference and have the same wall thickness as the annular structure, which is used to connect adjacent annular resonant structures. The number of electrodes is 48, of which 24 electrodes are evenly distributed on the inner side of the nested annular resonator, 16 electrodes are distributed on the outer side of the nested annular resonator, and 8 electrodes are distributed on the anchor points.

[0029] The micromechanical annular nested gyroscope includes three-order wine glass-shaped degenerate modes, one of which can be referred to as the first mode, and the other detects the second mode. Among the above 48 electrodes, the first driving electrodes supporting the first mode are 81, 82, 83, and the first detection electrodes are 71, 72, 73. The second driving electrodes supporting the second mode are 61, 62, 63, and the second detection electrodes are 51, 52, 53. There are also electrodes 101, 102, 103, 104, 105, 106, 107, 108, 109, 110, 201, 202, 203, 204, 205, 206, 207, 208, 209, 210, which are used to achieve stiffness decoupling of the first mode and the second mode. The electrodes 301, 302, 303, 304 are used to adjust the resonance frequency of the first mode, and the electrodes 401, 402, 403, 404 are used to adjust the resonance frequency of the second mode. The electrodes located on the anchor structure are used to provide a bias voltage.

[0030] The operating modes of the micromechanical nested ring gyroscope in the present application are a set of degenerate third-order wine glass modes with the lowest resonant frequency, while the resonant frequencies of the in-plane translational modes and out-of-plane barrel modes that are sensitive to external acceleration are higher than the operating modes, thereby reducing the vibration sensitivity of the gyroscope to external acceleration.

[0031] When the micromechanical gyroscope works, the nested ring resonator will first be Figure 3 The first mode of the third-order wine glass mode shown in the figure enters the resonant state and maintains a stable vibration frequency and amplitude. When the sensor frame rotates around the sensitive axis, the coupling effect generated by the Coriolis force will change the resonator. Figure 3 The vibration state of the second mode of the third-order wine glass mode is shown in FIG. By measuring the vibration amplitude of the second mode, the current angular velocity can be obtained.

[0032] Figure 4 is the in-plane translational mode of the micromechanical nested ring gyroscope, Figure 5This is the out-of-plane barrel mode of the micromechanical nested ring gyroscope. When the number and wall thickness of the ring resonant structures are specific values, their resonant frequencies can be higher than the resonant frequency of the working mode. The higher the resonant frequency, the less sensitive it is to external acceleration. The resonant frequency of the working mode of the gyroscope is kept at a relatively low level, which helps to improve mechanical sensitivity and reduce mechanical thermal noise.

[0033] It can be seen from the above technical solution that this embodiment provides a micromechanical nested ring gyroscope, including a substrate and a support structure arranged on the substrate, a nested ring resonator and a plurality of electrodes. The support structure includes an anchor point and a flexible support component, the anchor point is connected to the substrate, the flexible support component is connected to the anchor point, and is used to support the nested ring resonator. Since a support structure with a flexible support component is adopted, the conduction of stress caused by temperature changes can be reduced. By adjusting the structural parameters, the resonant frequency of the gyroscope working mode is optimized, and the vibration sensitivity of the gyroscope is reduced. Thereby, the problem of performance degradation of the micromechanical gyroscope when working in a harsh environment can be solved.

[0034] The various embodiments in this specification are described in a progressive manner, and each embodiment focuses on the differences from other embodiments. The same or similar parts between the various embodiments can be referenced to each other.

[0035] Although the preferred embodiments of the present invention have been described, those skilled in the art may make additional changes and modifications to these embodiments once they have learned the basic creative concept. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments and all changes and modifications that fall within the scope of the embodiments of the present invention.

[0036] Finally, it should be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or terminal device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or terminal device. In the absence of further restrictions, the elements defined by the sentence "comprise a ..." do not exclude the existence of other identical elements in the process, method, article or terminal device including the elements.

[0037] The technical solution provided by the present invention is introduced in detail above. Specific examples are used in this article to illustrate the principle and implementation mode of the present invention. The description of the above embodiments is only used to help understand the method of the present invention and its core idea. At the same time, for those skilled in the art, according to the idea of ​​the present invention, there will be changes in the specific implementation mode and application scope. In summary, the content of this specification should not be understood as limiting the present invention.

Claims

1. A micromechanical nested ring gyroscope, characterized in that: The invention comprises a substrate and a support structure arranged on the substrate, a nested ring resonator and a plurality of electrodes, wherein: The support structure includes an anchor point and a flexible support component, wherein the anchor point is connected to the substrate, and the flexible support component is connected to the anchor point and is used to support the nested ring resonator.

2. The micromechanical nested ring gyroscope according to claim 1, characterized in that: The support structure, the nested ring resonator and the plurality of electrodes are all made of SOI wafers with a (100) crystal plane.

3. The micromechanical nested ring gyroscope according to claim 1, characterized in that: The flexible supporting component is a bent and folded flexible supporting beam.

4. The micromechanical nested ring gyroscope according to claim 1, characterized in that: The nested ring resonator includes a plurality of concentrically arranged ring resonant structures.

5. The micromechanical nested ring gyroscope according to claim 4, characterized in that: The wall thickness of each of the annular resonant structures is the same, and the distance between any two of the annular resonant structures is the same.

6. The micromechanical nested ring gyroscope according to claim 4, characterized in that: A plurality of spoke structures are arranged between any two of the annular resonant structures.

7. The micromechanical nested ring gyroscope according to claim 6, characterized in that: The wall thicknesses of any two of the spoke structures are the same.

8. The micromechanical nested ring gyroscope according to claim 1, characterized in that: The micromechanical nested ring gyroscope operates in two third-order wine glass-shaped degenerate modes.

9. The micromechanical nested ring gyroscope according to claim 8, characterized in that: The two third-order wine glass-shaped degenerate modes include a first mode and a second mode, and the electrodes include a plurality of first driving electrodes and first detecting electrodes for supporting the first mode, and also include second driving electrodes and second detecting electrodes for supporting the second mode.

10. The micromechanical nested ring gyroscope according to claim 9, characterized in that: The electrode further includes an anchor point electrode disposed on the anchor point for providing a bias voltage.

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