Fully decoupled tuning fork micromechanical gyroscope and method of use thereof

Abstract

The present application belongs to the field of gyroscopes, and particularly relates to a full decoupling tuning fork type micromechanical gyroscope and a use method thereof, and aims to solve the problem of insufficient detection precision of existing gyroscopes. The present application comprises a driving frame, a Coriolis mass block, a detection frame, a driving frame coupling beam, a lever coupling structure, an elastic beam, a support anchor point, a driving mode driving electrode, a driving mode detection electrode, a detection mode feedback electrode, a detection mode detection electrode, a frequency adjustment electrode, a quadrature adjustment electrode and a comb tooth pair structure. The present application adopts a three-frame structure topology form of the driving frame, the Coriolis mass block and the detection frame, realizes full decoupling of the driving mode and the detection mode, is conducive to reducing the coupling signal and improving the gyroscope precision; meanwhile, the independent topology form of the Coriolis mass block can also realize a larger Coriolis mass, increase the amplitude of the useful signal and improve the signal-to-noise ratio of the output signal.

Description

Technical Field

[0001] This invention belongs to the field of gyroscopes, specifically relating to a fully decoupled tuning fork micromechanical gyroscope and its usage method. Background Technology

[0002] Micromechanical gyroscopes are inertial sensors that combine microelectromechanical systems (MEMS) fabrication technology with gyroscope technology requirements. They can sensitively detect the angular velocity or absolute angle of a carrier's rotation relative to inertial space. Compared to GPS, they offer autonomous navigation advantages, such as not relying on external information, not radiating energy, and being less susceptible to external interference. Compared to traditionally fabricated micromechanical rotor gyroscopes, levitation gyroscopes, laser gyroscopes, and fiber optic gyroscopes, micromechanical gyroscopes offer numerous advantages, including small size, light weight, low power consumption, low cost, and ease of mass production, demonstrating their unparalleled strengths and making them one of the main development directions for gyroscopes. They have wide applications in aerospace, missile guidance, attitude control, and navigation positioning, and are particularly popular due to the growing demand in consumer electronics and the booming automotive industry.

[0003] The working principle of a tuning fork micromechanical gyroscope is based on the energy transfer between two vibration modes caused by the Coriolis force. Angular velocity is measured by reading the capacitance change at the sensing end. Tuning fork micromechanical gyroscopes are characterized by low manufacturing difficulty, good process compatibility, large sensing capacitance, and large driving displacement. They typically use an inverse vibration mode as the driving mode to suppress interference signals from the same-direction vibration mode induced by external environmental acceleration input.

[0004] However, the reverse drive mode of traditional tuning fork micromechanical gyroscopes has the following drawbacks: 1. The drive mode and detection mode are not completely decoupled. When the displacement of the drive mode is too large, it will increase the displacement noise of the detection mode, limiting the detection accuracy of the gyroscope. 2. There are co-phase vibration modes near the reverse drive mode and reverse detection mode. The detection ends of the drive mode and detection mode are easily interfered with by the nearby co-phase vibration modes. 3. There is no separate quadrature adjustment electrode. It is necessary to perform a series of complex operations such as phase calculation and amplitude detection on the quadrature error signal of the gyroscope in the measurement and control circuit to reduce the quadrature error. 4. It cannot flexibly adjust the frequency difference between the drive mode and the detection mode, and thus flexibly change the detection sensitivity of the gyroscope. 5. The sensitive frames on both sides of the gyroscope are independent of each other. They are easily affected by manufacturing errors, which can lead to frequency mismatch between the two sensitive frames, thereby increasing the error of the output signal. Summary of the Invention

[0005] To address the aforementioned problems in the prior art, namely the insufficient testing accuracy of existing gyroscopes, this invention provides a fully decoupled tuning fork micromechanical gyroscope, the gyroscope comprising:

[0006] 1. Drive frame; 2. Coriolis mass block; 3. Detection frame; 4. Drive frame coupling beam; 5. Lever coupling structure; 6. Elastic beam; 7. Support anchor point; 8. Drive mode drive electrode; 9. Drive mode detection electrode; 10. Detection mode feedback electrode; 11. Detection mode detection electrode; 12. Frequency adjustment electrode; 13. Orthogonal adjustment electrode; and 14. Comb tooth pair structure.

[0007] The elastic beam 6 includes a first elastic beam 6A, a second elastic beam 6B, a third elastic beam 6C, a fourth elastic beam 6D, and a fifth elastic beam 6E;

[0008] The support anchor point 7 includes a first support anchor point 7A, a second support anchor point 7B, and a third support anchor point 7C;

[0009] The comb tooth pair structure 14 includes a first comb tooth pair 14A, a second comb tooth pair 14B, and a third comb tooth pair 14C;

[0010] The rectangular coordinate system with the center of the gyroscope as the origin is denoted as the reference coordinate system;

[0011] The drive frame 1 includes a first drive frame 1A and a second drive frame 1B. The first drive frame 1A and the second drive frame 1B are symmetrically arranged about the Y-axis of the reference coordinate system. The first drive frame 1A and the second drive frame 1B have the motion degree of freedom in the X-axis direction of the reference coordinate system.

[0012] The drive frame coupling beam 4 includes a first drive frame coupling beam 4A and a second drive frame coupling beam 4B. The first drive frame coupling beam 4A is connected to the positive Y-axis side of the reference coordinate system of the first drive frame 1A and the positive Y-axis side of the reference coordinate system of the second drive frame 1B through a corresponding first elastic beam 6A. The second drive frame coupling beam 4B is connected to the negative Y-axis side of the reference coordinate system of the first drive frame 1A and the negative Y-axis side of the reference coordinate system of the second drive frame 1B through a corresponding first elastic beam 6A. The first drive frame coupling beam 4A and the second drive frame coupling beam 4B are fixed to the second support anchor point 7B through a fifth elastic beam 6E.

[0013] The Coriolis mass block 2 includes a first Coriolis mass block 2A and a second Coriolis mass block 2B. The first Coriolis mass block 2A is connected to the first drive frame 1A via a corresponding second elastic beam 6B, and the second Coriolis mass block 2B is connected to the second drive frame 1B via a corresponding second elastic beam 6B. The first Coriolis mass block 2A and the second Coriolis mass block 2B have degrees of freedom of motion in the X-axis direction and the Y-axis direction of the reference coordinate system. The detection frame 3 includes a first detection frame 3A and a second detection frame 3B. The first detection frame 3A is connected to the first Coriolis mass block 2A via a corresponding fourth elastic beam 6D, and the second detection frame 3B is connected to the second Coriolis mass block via a corresponding fourth elastic beam 6D. On 2B; the first detection frame 3A and the second detection frame 3B are respectively connected to the corresponding first support anchor point 7A and fixed through the third elastic beam 6C; the first detection frame 3A and the second detection frame 3B are connected through the lever coupling structure 5; the first detection frame 3A and the second detection frame 3B have the degree of freedom of motion in the Y-axis direction of the reference coordinate system; the fourth elastic beam 6D is set at both ends of the side of the first Coriolis mass block 2A parallel to the Y-axis direction of the reference coordinate system and at both ends of the side of the second Coriolis mass block 2B parallel to the Y-axis direction of the reference coordinate system; the third elastic beam 6C is set on the side of the first detection frame 3A parallel to the X-axis direction of the reference coordinate system and the side of the second detection frame 3B parallel to the X-axis direction of the reference coordinate system.

[0014] The lever coupling structure 5 is fixedly connected to the third support anchor point 7C at its center;

[0015] There are 4 driving mode driving electrodes 8, and 2 driving mode driving electrodes 8 form a group. The first group of driving mode driving electrodes 8 is set at both ends of the side of the reference coordinate system parallel to the Y axis of the reference coordinate system on the negative X-axis side of the reference coordinate system of the first driving frame 1A. The second group of driving mode driving electrodes 8 is set at both ends of the side of the reference coordinate system parallel to the Y axis of the reference coordinate system on the positive X-axis side of the reference coordinate system of the second driving frame 1B.

[0016] There are four driving mode detection electrodes 9, arranged in groups of two. The first group of driving mode detection electrodes 9 is located inside the first group of driving mode driving electrodes 8 on the side of the reference coordinate system of the first driving frame 1A, which is parallel to the Y-axis of the reference coordinate system. The second group of driving mode detection electrodes 9 is located inside the second group of driving mode driving electrodes 8 on the side of the reference coordinate system of the second driving frame 1B, which is parallel to the Y-axis of the reference coordinate system. The driving mode driving electrodes 8 are connected to the first driving frame 1A or the second driving frame 1B through a first comb pair 14A, forming a comb capacitor. The modal detection electrode 9 is connected to the first driving frame 1A or the second driving frame 1B via a first comb pair 14A, forming a comb capacitor; the inner side of each detection frame 3 is divided into two symmetrical detection areas by a lever coupling structure 5; each detection area is provided with a modal feedback electrode 10, a modal detection electrode 11, and a frequency adjustment electrode 12 in sequence from near to far from the lever coupling structure 5; the number of modal feedback electrodes 10, modal detection electrodes 11, and frequency adjustment electrodes 12 are all 4; the modal feedback electrodes 10, modal detection electrodes 11, and frequency adjustment electrodes 12 are connected via a second comb pair 14B;

[0017] There are 8 orthogonal adjustment electrodes 13, with 2 orthogonal adjustment electrodes 13 forming a group. Each group of orthogonal adjustment electrodes 13 is respectively set on both sides of the X-axis of the reference coordinate system outside the edge of the detection frame 3 on the Coriolis mass block 2, which is parallel to the Y-axis of the reference coordinate system. The orthogonal adjustment electrodes 13 and the Coriolis mass block 2 are connected through the third comb pair 14C to form a comb capacitance.

[0018] In some preferred embodiments, the driving mode driving electrode 8 operates as follows: after a driving voltage excitation signal is applied to the driving mode driving electrode 8, the voltage signal is converted into a first electrostatic force through the first comb pair 14A, and the first electrostatic force excites the driving frame 1 to move along the X-axis direction of the reference coordinate system.

[0019] In some preferred embodiments, the driving mode detection electrode 9 operates by converting the displacement of the driving frame 1 in the X-axis direction of the reference coordinate system into a first capacitance change on the first comb tooth pair 14A, the first capacitance change being converted into a first current change on the driving mode detection electrode 9, and the first current change being transmitted to the gyroscope processing circuit.

[0020] In some preferred embodiments, the detection mode feedback electrode 10 operates such that after a feedback voltage signal is applied to the detection mode feedback electrode 10, the feedback voltage signal is converted into a second electrostatic force through the second comb pair 14B. The second electrostatic force counteracts the movement tendency of the detection frame 3 along the Y-axis direction of the reference coordinate system.

[0021] In some preferred embodiments, the detection mode detection electrode 11 operates by converting the magnitude of the displacement of the detection frame 3 in the Y-axis direction of the reference coordinate system into a second capacitance change on the second comb pair 14B, which is then converted into a second current change on the detection mode detection electrode 11 and transmitted to the gyroscope processing circuit.

[0022] In some preferred embodiments, the frequency adjustment electrode 12 is used to adjust the resonant frequency of the detection frame 3.

[0023] In some preferred embodiments, the orthogonal adjustment electrode 13 is used to adjust the motion angle of the Coriolis mass block 2 along the X-axis direction of the reference coordinate system.

[0024] In another aspect, the present invention proposes a method for using a fully decoupled tuning fork micromechanical gyroscope, the method being implemented based on the above-mentioned fully decoupled tuning fork micromechanical gyroscope, the method comprising: step S100, applying a working power supply to the gyroscope to cause the gyroscope to enter the driving mode;

[0025] Step S200: The gyroscope monitors the angular velocity input in real time;

[0026] In step S300, when an angular velocity input is detected, the Coriolis force is generated because the drive frame 1 and the Coriolis mass 2 keep moving. The direction of the Coriolis force is perpendicular to the X-axis of the reference coordinate system of the motion direction, and the direction of the Coriolis force is along the Y-axis of the reference coordinate system. Since the Y-axis constraint of the reference coordinate system of the drive frame 1 is extremely large, it cannot produce displacement in the Y-axis direction of the reference coordinate system. Only the Coriolis mass 2 moves periodically in opposite directions or towards each other along the Y-axis direction of the reference coordinate system under the action of the Coriolis force.

[0027] The first Coriolis mass block 2A and the second departmental mass block 2B are driven by the fourth elastic beam 6D to make the first detection frame 3A and the second detection frame 3B move in complete synchronization with the first Coriolis mass block 2A and the second Coriolis mass block 2B along the Y-axis of the reference coordinate system.

[0028] The first detection frame 3A and the second detection frame 3B move in opposite directions synchronously due to the constraint of the lever coupling structure 5.

[0029] Step S400: Based on the motion displacement of the detection frame 3 in the Y-axis direction of the reference coordinate system, it is converted into a second capacitance change on the second comb tooth pair 14B. The second capacitance change is converted into a second current change on the detection mode detection electrode 11 and transmitted to the gyroscope processing circuit to read the second current change. The magnitude of the angular velocity input to be measured is obtained by detecting the second current change.

[0030] By applying a feedback voltage signal to the detection mode feedback electrode 10, the feedback voltage signal generates an electrostatic force through the second comb tooth 14B. The direction of the electrostatic force is opposite to the direction of the Coriolis force, which cancels out the motion tendency of the detection frame 3 and restores it to a stationary state.

[0031] In some preferred embodiments, the driving mode specifically includes:

[0032] A working power supply is applied to the driving mode driving electrode 8, which excites the first driving frame 1A and the second driving frame 1B to periodically alternate towards or opposite each other along the X-axis of the reference coordinate system. The driving frames 1A and 1B, via the second elastic beam 6B, respectively drive the first Coriolis mass block 2A and the second Coriolis mass block 2B to move in complete synchronization with the first driving frame 1A and the second driving frame 1B along the X-axis of the reference coordinate system. In some preferred embodiments, the method further includes applying a DC voltage to the frequency adjustment electrode 12 to apply electrostatic negative stiffness to the gyroscope structure. The stiffness and mass jointly determine the frequency. By changing the frequency difference between the detection mode and the driving mode, the vibration frequency of the detection mode is changed, thereby adjusting the detection sensitivity.

[0033] In some preferred embodiments, the method further includes a method for canceling the quadrature error signal, specifically: adjusting the quadrature control electrical signal applied by the quadrature adjustment electrode 13 according to the replication of the quadrature error signal until the quadrature error signal output is 0.

[0034] The beneficial effects of this invention are:

[0035] (1) The fully decoupled tuning fork micromechanical gyroscope of the present invention adopts a three-frame structure topology of driving frame, Coriolis mass block and detection frame. This structure can realize the complete decoupling of driving mode and detection mode, which is beneficial to reduce coupling signal and improve gyroscope accuracy. At the same time, the independent topology of Coriolis mass block can also realize a larger Coriolis mass, increase the amplitude of useful signal and improve the signal-to-noise ratio of output signal.

[0036] (2) Both the driving frame and the detection frame are coupled by structures such as coupling beams and levers, which have a good suppression effect on the same-direction vibration mode. While keeping the driving mode and the detection mode frequency unchanged, the frequency of the same-direction vibration mode is increased, and the frequency difference between the driving mode, the detection mode and the same-direction vibration mode is widened. This is conducive to the energy concentration in the frequency band where the driving mode and the detection mode are located, achieving higher sensitivity, and at the same time effectively reducing the interference of the same-direction vibration mode on the detection end of the driving and detection modes.

[0037] (3) Adding a separate orthogonal adjustment electrode to the Coriolis mass block is specifically used to adjust the orthogonal error of the Coriolis mass block, which greatly simplifies the signal processing flow, reduces the difficulty of signal processing, reduces the orthogonal error signal of the gyroscope, and helps to improve the performance of the gyroscope.

[0038] (4) A separate frequency adjustment electrode is set in the detection frame, which is specifically used to flexibly adjust the frequency difference between the driving mode and the detection mode, thereby flexibly changing the detection sensitivity of the gyroscope. The frequency difference can be adjusted according to the range and accuracy requirements in actual use to adapt to different needs, avoiding the need to design different structures for different requirements, thus broadening the application range of the gyroscope and reducing costs.

[0039] (5) In traditional tuning fork micromechanical gyroscopes, the two detection frames are independent of each other. Manufacturing errors can cause stiffness differences between the two detection frames, leading to inconsistent vibration frequencies. This results in different frequency responses (sensitivity) between the different detection frames, which cannot be canceled after differential signal processing, causing common-mode errors and affecting the gyroscope's accuracy. In this invention, the detection frames are coupled using a lever structure. When manufacturing errors occur, the lever structure compensates for the stiffness differences between the different detection frames caused by the manufacturing errors, ensuring that the vibration frequency and signal amplitude-frequency response of the different detection frames remain consistent, thereby avoiding the occurrence of common-mode error signals in the output. Attached Figure Description

[0040] Other features, objects, and advantages of this application will become more apparent from the following detailed description of non-limiting embodiments with reference to the accompanying drawings:

[0041] Figure 1 This is a schematic diagram of a fully decoupled tuning fork micromechanical gyroscope in an embodiment of the present invention;

[0042] Figure 2 This is a schematic diagram of the fully decoupled tuning fork micromechanical gyroscope driving mode in the second embodiment of the present invention;

[0043] Figure 3 This is a schematic diagram of the detection mode of the fully decoupled tuning fork micromechanical gyroscope in the third embodiment of the present invention;

[0044] Figure 4 This is a schematic diagram of the orthogonal adjustment process of the fully decoupled tuning fork micromechanical gyroscope in the third embodiment of the present invention.

[0045] The attached figures include: a first drive frame 1A, a second drive frame 1B, a first Coriolis mass block 2A, a second Coriolis mass block 2B, a first detection frame 3A, a second detection frame 3B, a first drive frame coupling beam 4A, a second drive frame coupling beam 4B, a lever coupling structure 5, an elastic beam 6, a support anchor point 7, a drive mode drive electrode 8, a drive mode detection electrode 9, a detection mode feedback electrode 10, a detection mode detection electrode 11, a frequency adjustment electrode 12, an orthogonal adjustment electrode 13, and a comb tooth pair structure 14.

[0046] The first elastic beam 6A, the second elastic beam 6B, the third elastic beam 6C, the fourth elastic beam 6D, and the fifth elastic beam 6E;

[0047] First support anchor point 7A, second support anchor point 7B and third support anchor point 7C;

[0048] First comb pair 14A, second comb pair 14B and third comb pair 14C. Detailed Implementation

[0049] The present application will now be described in further detail with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are for illustrative purposes only and are not intended to limit the invention. Furthermore, it should be noted that, for ease of description, only the parts relevant to the invention are shown in the accompanying drawings.

[0050] It should be noted that, unless otherwise specified, the embodiments and features described in this application can be combined with each other. This application will now be described in detail with reference to the accompanying drawings and embodiments.

[0051] To more clearly explain the fully decoupled tuning fork micromechanical gyroscope of the present invention, the following will be combined with... Figure 1 The components in the embodiments of the present invention will be described in detail below.

[0052] The purpose of this invention is to provide a gyroscope with low manufacturing difficulty, good process compatibility, large detection capacitance, and large driving displacement. Furthermore, it employs a three-frame topology to achieve complete decoupling of the driving and detection modes, avoiding displacement noise to the detection mode caused by excessive driving mode displacement, thus improving the gyroscope's detection accuracy. Increasing the frequency difference between the reverse driving mode, reverse detection mode, and co-directional vibration mode reduces interference from the co-directional vibration mode to the detection ends of the driving and detection modes. A separate orthogonal adjustment electrode is added to the Coriolis mass block specifically for adjusting the orthogonal error of the Coriolis mass block, greatly simplifying signal processing, reducing orthogonal error, and improving measurement accuracy. A frequency adjustment electrode is added to flexibly adjust the frequency difference between the driving and detection modes, thereby flexibly changing the gyroscope's detection sensitivity. The sensitive frames on both sides of the gyroscope are coupled together through a lever structure, providing stronger robustness to manufacturing errors and ensuring that the vibration frequency and signal amplitude-frequency response gain of the two sensitive frames remain consistent, avoiding the occurrence of common-mode error in the output.

[0053] The fully decoupled tuning fork micromechanical gyroscope of the first embodiment of the present invention includes a step drive frame 1, a Coriolis mass block 2, a detection frame 3, a drive frame coupling beam 4, a lever coupling structure 5, an elastic beam 6, a support anchor point 7, a drive mode drive electrode 8, a drive mode detection electrode 9, a detection mode feedback electrode 10, a detection mode detection electrode 11, a frequency adjustment electrode 12, an orthogonal adjustment electrode 13, and a comb tooth pair structure 14. Detailed descriptions of each component are as follows:

[0054] The elastic beam 6 includes a first elastic beam 6A, a second elastic beam 6B, a third elastic beam 6C, a fourth elastic beam 6D, and a fifth elastic beam 6E;

[0055] The support anchor point 7 includes a first support anchor point 7A, a second support anchor point 7B, and a third support anchor point 7C;

[0056] The comb tooth pair structure 14 includes a first comb tooth pair 14A, a second comb tooth pair 14B, and a third comb tooth pair 14C; in this embodiment, the number of comb tooth pairs can be any number under the condition of satisfying process constraints.

[0057] The rectangular coordinate system with the center of the gyroscope as the origin is denoted as the reference coordinate system; the drive frame 1 includes a first drive frame 1A and a second drive frame 1B, the first drive frame 1A and the second drive frame 1B are symmetrically arranged with respect to the Y-axis of the reference coordinate system; the first drive frame 1A and the second drive frame 1B have the motion degree of freedom in the X-axis direction of the reference coordinate system.

[0058] The drive frame coupling beam 4 includes a first drive frame coupling beam 4A and a second drive frame coupling beam 4B. The first drive frame coupling beam 4A is connected to the positive Y-axis side of the reference coordinate system of the first drive frame 1A and the positive Y-axis side of the reference coordinate system of the second drive frame 1B through a corresponding first elastic beam 6A. The second drive frame coupling beam 4B is connected to the negative Y-axis side of the reference coordinate system of the first drive frame 1A and the negative Y-axis side of the reference coordinate system of the second drive frame 1B through a corresponding first elastic beam 6A. The first drive frame coupling beam 4A and the second drive frame coupling beam 4B are fixed to the second support anchor point 7B through a fifth elastic beam 6E.

[0059] The Coriolis mass block 2 includes a first Coriolis mass block 2A and a second Coriolis mass block 2B. The first Coriolis mass block 2A is connected to the first drive frame 1A via a corresponding second elastic beam 6B, and the second Coriolis mass block 2B is connected to the second drive frame 1B via a corresponding second elastic beam 6B. The first Coriolis mass block 2A and the second Coriolis mass block 2B have degrees of freedom of motion in the X-axis direction and the Y-axis direction of the reference coordinate system. The detection frame 3 includes a first detection frame 3A and a second detection frame 3B. The first detection frame 3A is connected to the first Coriolis mass block 2A via a corresponding fourth elastic beam 6D, and the second detection frame 3B is connected to the second Coriolis mass block 2B via a corresponding fourth elastic beam 6D. The first detection frame 3A... The first and second detection frames 3B are respectively connected to the corresponding first support anchor points 7A and fixed through the third elastic beam 6C; the first detection frame 3A and the second detection frame 3B are connected through the lever coupling structure 5; the first detection frame 3A and the second detection frame 3B have a degree of freedom of motion in the Y-axis direction of the reference coordinate system; the fourth elastic beam 6D is set at both ends of the side of the first Coriolis mass block 2A parallel to the Y-axis direction of the reference coordinate system and at both ends of the side of the second Coriolis mass block 2B parallel to the Y-axis direction of the reference coordinate system; the third elastic beam 6C is set on the side of the first detection frame 3A parallel to the X-axis direction of the reference coordinate system and the side of the second detection frame 3B parallel to the X-axis direction of the reference coordinate system; the center of the lever coupling structure 5 is connected and fixed to the third support anchor point 7C;

[0060] There are four driving mode driving electrodes 8, with two driving mode driving electrodes 8 forming a group. The first group of driving mode driving electrodes 8 is located at both ends of the side parallel to the Y-axis of the reference coordinate system on the negative X-axis side of the reference coordinate system of the first driving frame 1A. The second group of driving mode driving electrodes 8 is located at both ends of the side parallel to the Y-axis of the reference coordinate system on the positive X-axis side of the reference coordinate system of the second driving frame 1B. In this embodiment, the driving mode driving electrodes 8 operate as follows: after a driving voltage excitation signal is applied to the driving mode driving electrodes 8, the voltage signal is converted into a first electrostatic force through the first comb tooth 14A. The first electrostatic force excites the driving frame 1 to move along the X-axis direction of the reference coordinate system.

[0061] There are four driving mode detection electrodes 9, with two driving mode detection electrodes 9 forming a group. The first group of driving mode detection electrodes 9 is located inside the first group of driving mode driving electrodes 8 on the side of the reference coordinate system of the first driving frame 1A in the negative X-axis direction and parallel to the Y-axis of the reference coordinate system. The second group of driving mode detection electrodes 9 is located inside the second group of driving mode driving electrodes 8 on the side of the reference coordinate system of the second driving frame 1B in the positive X-axis direction and parallel to the Y-axis of the reference coordinate system. The driving mode driving electrodes 8 are connected to the first driving frame 1A or the second driving frame 1B through the first comb tooth pair 14A, forming a comb tooth capacitor.

[0062] In this embodiment, the driving mode detection electrode 9 operates by converting the displacement of the driving frame 1 in the X-axis direction of the reference coordinate system into a first capacitance change on the first comb tooth pair 14A. The first capacitance change is then converted into a first current change on the driving mode detection electrode 9, and the first current change is transmitted to the gyroscope processing circuit.

[0063] The inner side of each detection frame 3 is divided into two symmetrical detection areas by a lever coupling structure 5; each detection area is provided with a detection mode feedback electrode 10, a detection mode detection electrode 11, and a frequency adjustment electrode 12 in sequence from near to far from the lever coupling structure 5; the number of detection mode feedback electrodes 10, detection mode detection electrodes 11, and frequency adjustment electrodes 12 are all 4; the detection mode feedback electrodes 10, detection mode detection electrodes 11, and frequency adjustment electrodes 12 are connected by a second comb tooth pair 14B;

[0064] In this embodiment, the detection mode feedback electrode 10 operates as follows: after a feedback voltage signal is applied to the detection mode feedback electrode 10, the feedback voltage signal is converted into a second electrostatic force through the second comb pair 14B. The second electrostatic force counteracts the movement trend of the detection frame 3 along the Y-axis direction of the reference coordinate system.

[0065] In this embodiment, the detection mode detection electrode 11 operates by converting the magnitude of the displacement of the detection frame 3 in the Y-axis direction of the reference coordinate system into a second capacitance change on the second comb pair 14B. The second capacitance change is then converted into a second current change on the detection mode detection electrode 11, and the second current change is transmitted to the gyroscope processing circuit.

[0066] In this embodiment, the frequency adjustment electrode 12 is used to adjust the resonant frequency of the detection frame 3.

[0067] In this embodiment, the orthogonal adjustment electrode 13 is used to adjust the motion angle of the Coriolis mass block 2 along the X-axis direction of the reference coordinate system.

[0068] There are 8 orthogonal adjustment electrodes 13, with 2 orthogonal adjustment electrodes 13 forming a group. Each group of orthogonal adjustment electrodes 13 is respectively set on both sides of the X-axis of the reference coordinate system outside the edge of the detection frame 3 on the Coriolis mass block 2, which is parallel to the Y-axis of the reference coordinate system. The orthogonal adjustment electrodes 13 and the Coriolis mass block 2 are connected through the third comb pair 14C to form a comb capacitance.

[0069] The method for using the fully decoupled tuning fork micromechanical gyroscope according to the second embodiment of the present invention is based on the above-described fully decoupled tuning fork micromechanical gyroscope, and the method includes:

[0070] Step S100: Apply operating power to the gyroscope to make the gyroscope enter the driving mode;

[0071] In this embodiment, the driving mode of the gyroscope is as follows: Figure 2 As shown, specifically:

[0072] The driving frame 1 is excited by the driving mode driving electrode 8 to perform periodic alternating opposite or reciprocating motions along the X-axis of the reference coordinate system; the driving frame 1, through the second elastic beam 6B, drives the Coriolis mass block 2 to move synchronously with the driving frame 1 along the X-axis of the reference coordinate system. Figure 2 In the middle, the first drive frame 1A and the second drive frame 1B are coupled by the drive frame coupling beam 4.

[0073] Step S200: The gyroscope monitors the angular velocity input in real time;

[0074] Step S300, as follows Figure 3As shown, when an angular velocity input is detected, the driving frame 1 and the Coriolis mass 2 will generate a Coriolis force because they are constantly moving. The direction of the Coriolis force is perpendicular to the X-axis of the reference coordinate system of the motion direction, and the direction of the Coriolis force is along the Y-axis of the reference coordinate system. Since the Y-axis constraint of the reference coordinate system of the driving frame 1 is extremely large, it cannot produce displacement in the Y-axis direction of the reference coordinate system. Only the Coriolis mass 2 moves periodically and alternately towards or away from each other along the Y-axis direction of the reference coordinate system under the action of the Coriolis force. In this embodiment, the structural design makes the constraint of the driving frame in the Y-axis direction of the reference coordinate system extremely large.

[0075] The first Coriolis mass block 2A and the second departmental mass block 2B are driven by the fourth elastic beam 6D to make the first detection frame 3A and the second detection frame 3B move in complete synchronization with the first Coriolis mass block 2A and the second Coriolis mass block 2B along the Y-axis of the reference coordinate system.

[0076] The first detection frame 3A and the second detection frame 3B move in opposite directions synchronously due to the constraint of the lever coupling structure 5.

[0077] Step S400: Based on the motion displacement of the detection frame 3 in the Y-axis direction of the reference coordinate system, it is converted into a second capacitance change on the second comb tooth pair 14B. The second capacitance change is converted into a second current change on the detection mode detection electrode 11 and transmitted to the gyroscope processing circuit to read the second current change. The magnitude of the angular velocity input to be measured is obtained by detecting the second current change.

[0078] By applying a feedback voltage signal to the detection mode feedback electrode 10, the feedback voltage signal generates an electrostatic force through the second comb tooth 14B. The direction of the electrostatic force is opposite to the direction of the Coriolis force, which cancels out the movement of the detection frame 3 and restores it to a stationary state.

[0079] In this embodiment, the method further includes applying a DC voltage to the frequency adjustment electrode 12 to apply electrostatic negative stiffness to the gyroscope structure. The stiffness and mass together determine the frequency. By changing the frequency difference between the detection mode and the driving mode, the vibration frequency of the detection mode is changed, thereby adjusting the detection sensitivity. Applying a DC voltage to the frequency adjustment electrode 12 can adjust the resonant frequency of the reverse detection mode, which is specifically used to flexibly adjust the frequency difference between the driving mode and the detection mode. The DC voltage applied to the frequency adjustment electrode 12 can be adjusted according to the required frequency difference between the driving mode and the detection mode, thereby flexibly changing the detection sensitivity of the gyroscope. The frequency difference can be adjusted according to the range and accuracy requirements in actual use to adapt to different needs, avoiding the need to design different structures for different requirements, broadening the application range of the gyroscope, and reducing costs.

[0080] In this embodiment, the method further includes a method for canceling orthogonal error signals, such as... Figure 4 As shown, specifically: the quadrature control electrical signal applied by the quadrature adjustment electrode 13 is adjusted according to the replication of the quadrature error signal until the output of the quadrature error signal is 0;

[0081] Compared to the existing technology CN113686325A, this embodiment features a separate quadrature adjustment electrode. Applying a DC voltage to the quadrature adjustment electrode generates a clockwise or counterclockwise torque. The DC voltage applied to the quadrature adjustment electrode is adjusted according to the amplitude of the quadrature error signal until the quadrature error signal output is zero, thus canceling the quadrature error signal and avoiding measurement errors. A separate frequency adjustment electrode is also provided, specifically for flexibly adjusting the frequency difference between the driving mode and the detection mode. The DC voltage applied to the frequency adjustment electrode can be adjusted according to the actual required frequency difference, thereby flexibly changing the gyroscope's detection sensitivity. The frequency difference can be adjusted according to the range and accuracy requirements in actual use to adapt to different needs, avoiding the need to design different structures for different requirements, broadening the gyroscope's applicability, and reducing costs. Furthermore, in this embodiment, the detection frames on both sides of the detection mode employ a lever structure to achieve strong coupling, and a detection mode feedback electrode is also provided. While existing detection frames use torsional motion, the detection frames in this embodiment move in translational motion, resulting in better linearity, which is a key performance indicator for gyroscopes. Existing technologies cannot employ closed-loop control, but this embodiment specifically incorporates a detection mode feedback electrode, enabling closed-loop control and improving the gyroscope's range and linearity, both crucial performance indicators. Existing detection frames effectively suppress impact vibrations along the Y-axis of the reference coordinate system but lack fixed constraints on impact vibrations along the X-axis. Additionally, the angle between the detection capacitor and the X-axis of the reference coordinate system further hinders impact vibration suppression. In contrast, the lever structure of this patent provides fixed constraints along the X-axis of the reference coordinate system, and the detection capacitor, also along the Y-axis, achieves complete differential cancellation, thus effectively suppressing impact vibrations in both the X and Y axes of the reference coordinate system. This embodiment has a better effect in suppressing impact vibration.

[0082] Those skilled in the art will understand that, for the sake of convenience and brevity, the specific working process and related descriptions of the system described above can be found in the corresponding processes in the foregoing method embodiments, and will not be repeated here.

[0083] Those skilled in the art will understand that, for the sake of convenience and brevity, the specific working process and related descriptions of the storage device and processing device described above can be referred to the corresponding process in the foregoing method embodiments, and will not be repeated here.

[0084] The terms “first”, “second”, etc., are used to distinguish similar objects, not to describe or indicate a specific order or sequence.

[0085] The term "comprising" or any other similar term is intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus / device that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent in such process, method, article, or apparatus / device.

[0086] The technical solution of the present invention has been described above with reference to the preferred embodiments shown in the accompanying drawings. However, it will be readily understood by those skilled in the art that the scope of protection of the present invention is obviously not limited to these specific embodiments. Without departing from the principles of the present invention, those skilled in the art can make equivalent changes or substitutions to the relevant technical features, and the technical solutions after these changes or substitutions will all fall within the scope of protection of the present invention.

Claims

1. A fully decoupled tuning fork micromechanical gyroscope, characterized in that, The gyroscope includes: Drive frame (1), Coriolis mass block (2), detection frame (3), drive frame coupling beam (4), lever coupling structure (5), elastic beam (6), support anchor point (7), drive mode drive electrode (8), drive mode detection electrode (9), detection mode feedback electrode (10), detection mode detection electrode (11), frequency adjustment electrode (12), orthogonal adjustment electrode (13), and comb tooth pair structure (14); The elastic beam (6) includes a first elastic beam (6A), a second elastic beam (6B), a third elastic beam (6C), a fourth elastic beam (6D), and a fifth elastic beam (6E). The support anchor point (7) includes a first support anchor point (7A), a second support anchor point (7B) and a third support anchor point (7C); The comb tooth pair structure (14) includes a first comb tooth pair (14A), a second comb tooth pair (14B), and a third comb tooth pair (14C). The rectangular coordinate system with the center of the gyroscope as the origin is denoted as the reference coordinate system; The drive frame (1) includes a first drive frame (1A) and a second drive frame (1B). The first drive frame (1A) and the second drive frame (1B) are symmetrically arranged about the Y-axis of the reference coordinate system. The first drive frame (1A) and the second drive frame (1B) have the motion degree of freedom in the X-axis direction of the reference coordinate system. The drive frame coupling beam (4) includes a first drive frame coupling beam (4A) and a second drive frame coupling beam (4B). The first drive frame coupling beam (4A) is connected to the positive Y-axis side of the reference coordinate system of the first drive frame (1A) and the positive Y-axis side of the reference coordinate system of the second drive frame (1B) through a corresponding first elastic beam (6A). The second drive frame coupling beam (4B) is connected to the negative Y-axis side of the reference coordinate system of the first drive frame (1A) and the negative Y-axis side of the reference coordinate system of the second drive frame (1B) through a corresponding first elastic beam (6A). The first drive frame coupling beam (4A) and the second drive frame coupling beam (4B) are fixed to the second support anchor point (7B) through a fifth elastic beam (6E). The Coriolis mass block (2) includes a first Coriolis mass block (2A) and a second Coriolis mass block (2B). The first Coriolis mass block (2A) is connected to the corresponding first drive frame (1A) through a corresponding second elastic beam (6B), and the second Coriolis mass block (2B) is connected to the second drive frame (1B) through a corresponding second elastic beam (6B). The first Coriolis mass block (2A) and the second Coriolis mass block (2B) have a degree of freedom of motion in the X-axis direction of the reference coordinate system and a degree of freedom of motion in the Y-axis direction of the reference coordinate system. The detection frame (3) includes a first detection frame (3A) and a second detection frame (3B). The first detection frame (3A) is connected to the first Coriolis mass block (2A) via a corresponding fourth elastic beam (6D), and the second detection frame (3B) is connected to the second Coriolis mass block (2B) via a corresponding fourth elastic beam (6D). The first detection frame (3A) and the second detection frame (3B) are respectively connected to the corresponding first support anchor point (7A) via a third elastic beam (6C). The first detection frame (3A) and the second detection frame (3B) are connected by a communication channel. The first detection frame (3A) and the second detection frame (3B) are connected by a lever coupling structure (5); the first detection frame (3A) and the second detection frame (3B) have a degree of freedom of motion in the Y-axis direction of the reference coordinate system; the fourth elastic beam (6D) is set at both ends of the side of the first Coriolis mass block (2A) parallel to the Y-axis direction of the reference coordinate system and at both ends of the side of the second Coriolis mass block (2B) parallel to the Y-axis direction of the reference coordinate system; the third elastic beam (6C) is set on the side of the first detection frame (3A) parallel to the X-axis direction of the reference coordinate system and the side of the second detection frame (3B) parallel to the X-axis direction of the reference coordinate system. The lever coupling structure (5) is fixedly connected to the third support anchor point (7C) at its center; The number of driving mode driving electrodes (8) is 4. Every 2 driving mode driving electrodes (8) form a group. The first group of driving mode driving electrodes is set at both ends of the side parallel to the Y axis of the reference coordinate system on the negative X-axis side of the reference coordinate system of the first driving frame (1A). The second group of driving mode driving electrodes is set at both ends of the side parallel to the Y axis of the reference coordinate system on the positive X-axis side of the reference coordinate system of the second driving frame (1B). There are 4 driving mode detection electrodes (9), and each pair of driving mode detection electrodes (9) forms a group. The first group of driving mode detection electrodes is located inside the first group of driving mode driving electrodes (8) on the side of the reference coordinate system of the first driving frame (1A) in the negative X-axis direction and parallel to the Y-axis of the reference coordinate system. The second group of driving mode detection electrodes is located inside the second group of driving mode driving electrodes (8) on the side of the reference coordinate system of the second driving frame (1B) in the positive X-axis direction and parallel to the Y-axis of the reference coordinate system. The driving mode driving electrodes (8) are connected to the first driving frame (1A) or the second driving frame (1B) through the first comb tooth pair (14A) to form a comb tooth capacitor. The driving mode detection electrodes (9) are connected to the first driving frame (1A) or the second driving frame (1B) through the first comb tooth pair (14A) to form a comb tooth capacitor. The inner side of each detection frame (3) is divided into two symmetrical detection areas by a lever coupling structure (5); each detection area is arranged with a detection modal feedback electrode (10), a detection modal detection electrode (11), and a frequency adjustment electrode (12) in sequence from near to far from the lever coupling structure (5); the number of detection modal feedback electrodes (10), detection modal detection electrodes (11), and frequency adjustment electrodes (12) are all 4; the detection modal feedback electrodes (10), detection modal detection electrodes (11), and frequency adjustment electrodes (12) are connected by a second comb tooth pair (14B); There are 8 orthogonal adjustment electrodes (13), and each pair of orthogonal adjustment electrodes (13) forms a group. Each group of orthogonal adjustment electrodes (13) is set on both sides of the X-axis of the reference coordinate system outside the edge of the detection frame (3) on the Coriolis mass block (2) that is parallel to the Y-axis of the reference coordinate system. The orthogonal adjustment electrodes (13) and the Coriolis mass block (2) are connected by the third comb pair (14C) to form a comb capacitor.

2. The fully decoupled tuning fork micromechanical gyroscope according to claim 1, characterized in that, The driving mode driving electrode (8) works as follows: after a driving voltage excitation signal is applied to the driving mode driving electrode (8), the voltage signal is converted into a first electrostatic force through the first comb pair (14A), and the first electrostatic force excites the driving frame (1) to move along the X-axis direction of the reference coordinate system.

3. The fully decoupled tuning fork micromechanical gyroscope according to claim 1, characterized in that, The driving mode detection electrode (9) works by converting the displacement of the driving frame (1) in the X-axis direction of the reference coordinate system into a first capacitance change on the first comb tooth pair (14A), and the first capacitance change is converted into a first current change on the driving mode detection electrode (9), and the first current change is transmitted to the gyroscope processing circuit.

4. The fully decoupled tuning fork micromechanical gyroscope according to claim 1, characterized in that, The detection mode feedback electrode (10) works as follows: after a feedback voltage signal is applied to the detection mode feedback electrode (10), the feedback voltage signal is converted into a second electrostatic force through the second comb pair (14B). The second electrostatic force cancels the movement trend of the detection frame (3) along the Y-axis direction of the reference coordinate system.

5. The fully decoupled tuning fork micromechanical gyroscope according to claim 1, characterized in that, The detection mode detection electrode (11) operates by converting the displacement of the detection frame (3) in the Y-axis direction of the reference coordinate system into a second capacitance change on the second comb pair (14B). The second capacitance change is then converted into a second current change on the detection mode detection electrode (11), and the second current change is transmitted to the gyroscope processing circuit.

6. The fully decoupled tuning fork micromechanical gyroscope according to claim 1, characterized in that, The frequency adjustment electrode (12) is used to adjust the resonant frequency of the detection frame (3).

7. The fully decoupled tuning fork micromechanical gyroscope according to claim 1, characterized in that, The orthogonal adjustment electrode (13) is used to adjust the motion angle of the Coriolis mass block (2) along the X-axis of the reference coordinate system.

8. A method for using a fully decoupled tuning fork micromechanical gyroscope, characterized in that, The method of use is implemented based on the fully decoupled tuning fork micromechanical gyroscope as described in any one of claims 1 to 7, and the method includes: Step S100: Apply operating power to the gyroscope to make the gyroscope enter the driving mode; Step S200: The gyroscope monitors the angular velocity input in real time; In step S300, when an angular velocity input is detected, a Coriolis force will be generated because the drive frame (1) and the Coriolis mass block (2) continue to move. The first Coriolis mass block (2A) and the second Coriolis mass block (2B) are driven by the fourth elastic beam (6D) to make the first detection frame (3A) and the second detection frame (3B) move in complete synchronization with the first Coriolis mass block (2A) and the second Coriolis mass block (2B) along the Y-axis of the reference coordinate system. The first detection frame (3A) and the second detection frame (3B) move in opposite directions synchronously due to the constraint of the lever coupling structure (5); Step S400: Based on the motion displacement of the detection frame (3) in the Y-axis direction of the reference coordinate system, the second capacitance change is converted into the second capacitance change on the second comb pair (14B). The second capacitance change is converted into the second current change on the detection mode detection electrode (11). The second current change is transmitted to the gyroscope processing circuit to read the second current change. The magnitude of the angular velocity input to be measured is obtained by detecting the second current change. By applying a feedback voltage signal to the detection mode feedback electrode (10), the feedback voltage signal generates an electrostatic force through the second comb pair (14B). The direction of the electrostatic force is opposite to the direction of the Coriolis force, which cancels out the motion tendency of the detection frame (3) and restores it to a stationary state.

9. The method of using a fully decoupled tuning fork micromechanical gyroscope according to claim 8, characterized in that, The driving mode is specifically as follows: Apply working power to the driving mode driving electrode (8), and excite the first driving frame (1A) and the second driving frame (1B) to perform periodic alternating opposite or reciprocating motions along the X-axis of the reference coordinate system through the driving mode driving electrode (8); the first driving frame (1A) and the second driving frame (1B) drive the first Coriolis mass block (2A) and the second Coriolis mass block (2B) to move in complete synchronization with the first driving frame (1A) and the second driving frame (1B) along the X-axis of the reference coordinate system through the second elastic beam (6B).

10. The method of using the fully decoupled tuning fork micromechanical gyroscope according to claim 8, characterized in that, The method further includes applying a DC voltage to the frequency adjustment electrode (12) to apply electrostatic negative stiffness to the gyroscope structure. The stiffness and mass together determine the frequency. The vibration frequency of the detection mode is changed by changing the frequency difference between the detection mode and the driving mode, thereby adjusting the detection sensitivity.

11. The method of using the fully decoupled tuning fork micromechanical gyroscope according to claim 9, characterized in that, The method also includes a method for canceling the quadrature error signal, specifically: adjusting the quadrature control electrical signal applied by the quadrature adjustment electrode (13) according to the amplitude of the quadrature error signal until the output of the quadrature error signal is 0.

Images