Single-axis MEMS gyroscope

Abstract

The single-axis MEMS gyroscope comprises a substrate, an anchor point assembly, a movement assembly and an electrode assembly, the movement assembly comprises a driving frame, a mass block and a detection frame, the driving frame is connected with a first anchor point through a first rigid beam, the driving frame has the freedom degree of linear movement in the X-axis direction relative to the substrate, the mass block is connected with the driving frame through a first decoupling beam, and the detection frame has the freedom degree of linear movement in the X-axis direction relative to the substrate. The detection frame is connected with the second anchor point through a second rigid beam, has a degree of freedom of linear motion along the X-axis direction relative to the substrate, and is further connected with the supporting beam through a first coupling beam, the extension direction of the first coupling beam forms acute included angles with the X-axis direction and the Y-axis direction, and the first coupling beam is provided with a first end and a second end in the extension direction; the first end of the first coupling beam is connected with the supporting beam, the second end of the first coupling beam is connected with the detection frame, and the supporting beam is connected with the third anchor point and connected with the mass block through the second decoupling beam. The device can achieve the amplification effect from the displacement of the mass block to the displacement of the detection frame.

Description

Technical Field

[0001] This invention relates to the field of detection technology, and in particular to a single-axis MEMS gyroscope. Background Technology

[0002] MEMS (Micro Electro Mechanical Systems) gyroscopes, due to their advantages of small size, low cost, low power consumption, and high integration, have been widely used in drones, automotive electronics, industrial production, and aerospace. With the development of related applications and the gradual increase in testing requirements, the market demand for small-sized, high-precision, and high-stability gyroscopes is becoming increasingly urgent.

[0003] Currently, typical MEMS gyroscopes are mainly capacitive resonant gyroscopes, whose basic principle is to obtain the angular velocity by measuring the energy transformation between different resonances caused by the Coriolis force. Traditional MEMS gyroscopes are hampered by low mechanical sensitivity of the sensitive modes and difficulty in improving the overall signal-to-noise ratio of the sensor, making it difficult to achieve further high-precision, low-noise performance. This invention improves the signal-to-noise ratio by introducing a sensitive mode mechanical sensitivity amplification structure, thereby realizing a high-precision, low-noise, high-performance MEMS gyroscope. At the same time, this invention has a simple structure, is easy to manufacture, and is conducive to mass production. Summary of the Invention

[0004] Therefore, this invention provides a single-axis MEMS gyroscope that can amplify the displacement of the mass block to the displacement of the detection frame, reduce the orthogonal error introduced by the process, and lay the foundation for realizing a high-performance MEMS gyroscope.

[0005] To address the aforementioned technical problems, this invention provides a single-axis MEMS gyroscope with a centrally symmetric structure, comprising: Substrate; An anchor point assembly, fixed on the substrate, includes a first anchor point, a second anchor point, and a third anchor point; A motion assembly includes a drive frame, a mass block, and a detection frame. The drive frame is connected to a first anchor point via a first rigid beam and has a degree of freedom of linear motion relative to the substrate along the X-axis. The mass block is connected to the drive frame via a first decoupling beam. The detection frame is connected to a second anchor point via a second rigid beam and has a degree of freedom of linear motion relative to the substrate along the X-axis. The detection frame is also connected to a support beam via a first coupling beam. The extension direction of the first coupling beam forms an acute angle with both the X-axis and Y-axis directions. The first coupling beam has a first end and a second end in its extension direction. The first end of the first coupling beam is connected to the support beam, and the second end of the first coupling beam is connected to the detection frame. The support beam is connected to the third anchor point, and the support beam is connected to the mass block via a second decoupling beam. The electrode assembly includes a driving mode excitation electrode and a sensitive mode detection electrode. The driving mode excitation electrode is used to drive the driving frame to move linearly along the X-axis direction, and the sensitive mode detection electrode is used to detect the displacement of the detection frame moving linearly along the X-axis direction. In the driving mode, the electrode assembly drives the driving frame to move linearly along the X-axis, and the driving frame drives the connected mass block to move linearly along the X-axis. In the detection mode, the mass block moves linearly along the Y-axis under the action of Coriolis force, and the mass block drives the connected detection frame to move linearly along the X-axis.

[0006] Furthermore, the motion component includes a motion unit, which includes two drive frames, two mass blocks, and two detection frames. The two drive frames are arranged at a distance along the Y-axis, and the two mass blocks are arranged at a distance along the Y-axis and are respectively connected to the two drive frames by the first decoupling beam. The two detection frames are arranged along the X-axis and are located between the two mass blocks and are connected by the second coupling beam. At the same time, the two mass blocks in the same motion unit move in opposite directions, and the two detection frames move in opposite directions.

[0007] Furthermore, each of the mass blocks has a support beam on one side facing the detection frame, and each of the two ends of the support beam along the X-axis is connected to the two ends of the adjacent mass block along the X-axis by a second decoupling beam. Each of the two ends of the support beam along the X-axis is connected to the ends of the two detection frames away from the center of the motion unit along the X-axis by a first coupling beam. The distance between the first end of the first coupling beam and the center of the motion unit along the X-axis is greater than the distance between the second end of the first coupling beam and the center of the motion unit along the X-axis.

[0008] Furthermore, the motion assembly includes two motion units, in which the mass block is embedded inside the drive frame connected thereto, and the two motion units are arranged along the X-axis and adjacent drive frames are connected by a third coupling beam; At the same time, the two motion units move in opposite directions.

[0009] Furthermore, a support beam is provided on one side of the two mass blocks arranged along the X-axis facing the detection frame. Each end of each support beam along the X-axis is connected to the two ends of the adjacent mass block along the X-axis through two second decoupling beams. Each end of each support beam along the X-axis is connected to the two ends of the two detection frames along the X-axis through the first coupling beam. The distance between the first end of the first coupling beam and the center of the motion unit along the X-axis is less than the distance between the second end of the first coupling beam and the center of the motion unit along the X-axis.

[0010] Furthermore, the motion assembly includes two motion units. In each motion unit, one mass block is embedded inside the drive frame connected to it and located at one end of the motion assembly along the Y-axis, and the other mass block is embedded inside the drive frame connected to it and located at the other end of the motion assembly along the Y-axis. The remaining two mass blocks of the two motion units are located at the center of the motion assembly and are fixed to each other to form a mass group. The remaining two drive frames of the two motion units are respectively located on both sides of the mass group along the X-axis. At the same time, the two motion units move in opposite directions.

[0011] Furthermore, a support beam is provided on one side of each mass block facing the detection frame. The midpoint of each support beam along the X-axis is connected to a point on the Y-axis symmetry axis of the mass block through a first decoupling beam. The midpoint of each support beam along the X-axis is connected to a point on the X-axis symmetry axis of the two detection frames through two first coupling beams. The distance between the first end of the first coupling beam and the center of the motion unit along the X-axis is less than the distance between the second end of the first coupling beam and the center of the motion unit along the X-axis.

[0012] Furthermore, the motion component includes four drive frames, four mass blocks, and two detection frames. The four drive frames are arranged in a rectangular array along the X-axis and Y-axis directions. The four mass blocks are arranged in a rectangular array along the X-axis and Y-axis directions and are respectively embedded in and connected to the four drive frames. One detection frame is located between two mass blocks arranged along the Y-axis direction, and the other detection frame is located between two other mass blocks arranged along the Y-axis direction. At the same time, the two mass blocks arranged along the X-axis move in opposite directions, the two mass blocks arranged along the Y-axis move in opposite directions, and the two detection frames arranged along the X-axis move in the same direction.

[0013] Furthermore, a support beam is provided on one side of the two mass blocks arranged along the X-axis facing the detection frame. Each end of each support beam along the X-axis is connected to the two ends of the adjacent mass block along the X-axis by two second decoupling beams. Each end of each support beam along the X-axis is connected to the two ends of the adjacent detection frame along the X-axis by two first coupling beams. The distance between the first end of the first coupling beam and the center of the motion component along the X-axis is less than the distance between the second end of the first coupling beam and the center of the motion component along the X-axis.

[0014] Furthermore, the anchor point assembly also includes a fourth anchor point, and levers are provided on both sides of the motion assembly in the X-axis direction. The levers are connected to the fourth anchor point through a torsion beam. The levers have a degree of freedom to rotate about the Z-axis direction relative to the substrate. The two ends of the levers along the length direction are respectively connected to the two closest drive frames along the Y-axis direction through a fourth coupling beam. The two closest drive frames along the Y-axis direction move in opposite directions.

[0015] Compared with the prior art, the above-mentioned technical solution of the present invention has the following advantages: The single-axis MEMS gyroscope of the present invention, on the one hand, by setting the first coupling beam, can realize the amplification effect of the displacement of the mass block to the displacement of the detection frame. The amplification of the detection frame displacement brings about the improvement of mechanical sensitivity, which can improve the signal-to-noise ratio of the gyroscope as a whole, optimize the zero-bias performance, and improve the accuracy of the existing MEMS gyroscope; on the other hand, by adopting a two-stage decoupling form, that is, the driving mode and the sensitive mode do not affect each other during the motion, the orthogonal error introduced by the process can be reduced, laying the foundation for realizing a high-performance MEMS gyroscope. Attached Figure Description

[0016] To make the content of this invention easier to understand, the invention will be further described in detail below with reference to specific embodiments and accompanying drawings.

[0017] Figure 1 This is a schematic diagram of the structure of a single-axis MEMS gyroscope in Embodiment 1 of the present invention; Figure 2 This is a schematic diagram of the driving modes of a single-axis MEMS gyroscope in Embodiment 1 of the present invention; Figure 3 This is a schematic diagram of the sensitive modes of a single-axis MEMS gyroscope in Embodiment 1 of the present invention; Figure 4 This is a schematic diagram of the electrode configuration in Embodiment 1 of the present invention; Figure 5 This is a schematic diagram of the structure of the single-axis MEMS gyroscope in Embodiment 2 of the present invention; Figure 6 This is a schematic diagram of the driving modes of the single-axis MEMS gyroscope in Embodiment 2 of the present invention; Figure 7 This is a schematic diagram of the sensitive modes of the single-axis MEMS gyroscope in Embodiment 2 of the present invention; Figure 8 This is a schematic diagram of the electrode configuration in Embodiment 2 of the present invention; Figure 9 This is a schematic diagram of the structure of the single-axis MEMS gyroscope in Embodiment 3 of the present invention; Figure 10 This is a schematic diagram of the driving modes of the single-axis MEMS gyroscope in Embodiment 3 of the present invention; Figure 11 This is a schematic diagram of the sensitive modes of a single-axis MEMS gyroscope in Embodiment 3 of the present invention; Figure 12 This is a schematic diagram of the electrode configuration in Embodiment 3 of the present invention; Figure 13 This is a schematic diagram of the structure of the single-axis MEMS gyroscope in Embodiment 4 of the present invention; Figure 14 This is a schematic diagram of the driving modes of the single-axis MEMS gyroscope in Embodiment 4 of the present invention; Figure 15 This is a schematic diagram of the sensitive modes of the single-axis MEMS gyroscope in Embodiment 4 of the present invention; Figure 16 This is a schematic diagram of the electrode configuration in Embodiment 4 of the present invention.

[0018] Explanation of reference numerals in the accompanying drawings: 11. First anchor point; 12. Second anchor point; 13. Third anchor point; 14. Fourth anchor point; 21. Drive frame; 22. Mass block; 23. Detection frame; 24. Lever; 31. First rigid beam; 32. Second rigid beam; 33. Support beam; 34. Torsion beam; 41. First decoupling beam; 42. Second decoupling beam; 51. First coupling beam; 52. Second coupling beam; 53. Third coupling beam; 54. Fourth coupling beam; 61. Drive mode excitation electrode; 62. Sensitive mode detection electrode; 63. Drive mode detection electrode; 64. Orthogonal stiffness tuning electrode. Detailed Implementation

[0019] The present invention will be further described below with reference to the accompanying drawings and specific embodiments, so that those skilled in the art can better understand and implement the present invention. However, the embodiments described are not intended to limit the present invention.

[0020] Example 1: See Figures 1 to 4 This invention discloses an embodiment of a single-axis MEMS gyroscope.

[0021] A single-axis MEMS gyroscope has a centrosymmetric structure. The aforementioned single-axis MEMS gyroscope includes: Substrate; An anchor point assembly, fixed on the substrate, includes a first anchor point 11, a second anchor point 12 and a third anchor point 13. The motion assembly includes a drive frame 21, a mass block 22, and a detection frame 23. The drive frame 21 is connected to the first anchor point 11 via a first rigid beam 31 and has a degree of freedom of linear motion relative to the substrate along the X-axis. The mass block 22 is connected to the drive frame 21 via a first decoupling beam 41. The detection frame 23 is connected to the second anchor point 12 via a second rigid beam 32 and has a degree of freedom of linear motion relative to the substrate along the X-axis. The detection frame 23 is also connected to a support beam 33 via a first coupling beam 51. The extension direction of the first coupling beam 51 forms an acute angle with both the X-axis and Y-axis directions. The first coupling beam 51 has a first end and a second end in its extension direction. The first end of the first coupling beam 51 is connected to the support beam 33, and the second end of the first coupling beam 51 is connected to the detection frame 23. The support beam 33 is connected to the third anchor point 13 and is connected to the mass block 22 via a second decoupling beam 42. The electrode assembly includes a driving mode excitation electrode 61 and a sensitive mode detection electrode 62. The driving mode excitation electrode 61 is used to drive the driving frame 21 to move linearly along the X-axis direction, and the sensitive mode detection electrode 62 is used to detect the displacement of the detection frame 23 moving linearly along the X-axis direction. In the driving mode, the electrode assembly drives the driving frame 21 to move linearly along the X-axis, and the driving frame 21 drives the connected mass block 22 to move linearly along the X-axis. In the detection mode, the mass block 22 moves linearly along the Y-axis under the action of Coriolis force, and the mass block 22 drives the connected detection frame 23 to move linearly along the X-axis.

[0022] In the above text, the gyroscope having a centrally symmetric structure refers to the layout in which the components of the gyroscope are symmetrically distributed with the geometric center of the structure as the symmetry point.

[0023] The substrate serves as the basic support base for the gyroscope, while the anchor point assembly is the connection fulcrum between the motion component and the substrate.

[0024] The drive frame 21 achieves periodic vibration in the X-axis direction by cooperating with the drive mode excitation electrode 61.

[0025] The first rigid beam 31 is a rigid microstructure beam connecting the drive frame 21 and the first anchor point 11. Its function is to fix the mounting support of the drive frame 21, and at the same time give the drive frame 21 the degree of freedom to move linearly only along the X-axis direction, while restricting the displacement in the Y-axis and Z-axis directions.

[0026] Mass block 22 is an inertial structure and the core component that generates the Coriolis force. Its mass directly affects the amplitude of the Coriolis force, and thus determines the detection sensitivity of the gyroscope.

[0027] The first decoupling beam 41 is a structure that connects the drive frame 21 and the mass block 22. It only allows the X-axis motion of the drive frame 21 to be transmitted to the mass block 22, blocks motion crosstalk in the Y-axis and Z-axis directions, and ensures that the drive frame 21 is not affected when the mass block 22 moves in the Y-axis direction.

[0028] The detection frame 23 acquires displacement signals by cooperating with the sensitive mode detection electrode 62.

[0029] The second rigid beam 32 is a structure that connects the detection frame 23 and the second anchor point 12, giving the detection frame 23 the degree of freedom to move linearly only along the X-axis direction, ensuring that the detection frame 23 only responds to displacement changes in the X-axis direction.

[0030] The first coupling beam 51 is the core structure for motion direction conversion. Its function is to convert the linear Y-axis motion of the mass block 22 into the linear X-axis motion of the detection frame 23, achieving a matching conversion between the "Coriolis force direction" and the "detection direction". After the first coupling beam 51 is subjected to the Y-axis motion caused by the mass block 22, the two first coupling beams 51 arranged along the Y-axis cancel out the Y-axis motion. According to the principle of force composition, the end of the first coupling beam 51 connected to the detection frame 23 will move along the X-axis. The angle between the first coupling beam 51 and the Y-axis determines the displacement amplification ratio.

[0031] The support beam 33 is a structure that connects the first decoupling beam 41 and the first coupling beam 51, giving the first coupling beam 51 the degree of freedom to move linearly only along the Y-axis direction, while restricting the displacement in the X-axis and Z-axis directions.

[0032] The second decoupling beam 42 is a structure that connects the mass block 22 and the support beam 33. It only allows the Y-axis movement (driven by Coriolis force) of the mass block 22 to be transmitted to the support beam 33, blocking the movement interference in the X-axis direction, and ensuring that the detection frame 23 is not affected when the mass block 22 moves in the X-axis direction.

[0033] The electrode assembly is divided into two types: driving mode excitation electrode 61 and sensitive mode detection electrode 62, which respectively excite the driving motion and acquire the displacement. The driving mode excitation electrode 61 is paired with the driving frame 21 and generates an alternating electrostatic force by applying an alternating voltage, driving the driving frame 21 to perform periodic linear vibration along the X-axis, providing the basic motion velocity for the generation of Coriolis force. The sensitive mode detection electrode 62 is paired with the detection frame 23 and calculates the X-axis displacement of the detection frame 23 by detecting the change in capacitance between the electrode and the detection frame 23.

[0034] Specifically, in the driving mode, the driving mode excitation electrode 61 drives the driving frame 21 to perform periodic linear motion along the X-axis, and drives the mass block 22 to vibrate synchronously along the X-axis through the first decoupling beam 41. In the sensitive mode, the gyroscope has an angular velocity input, the mass block 22 moves along the Y-axis under the action of Coriolis force, and drives the detection frame 23 to move along the X-axis through the second decoupling beam 42, the support beam 33 and the first coupling beam 51. Finally, the displacement signal is collected by the sensitive mode detection electrode 62.

[0035] Through the above technical solutions, on the one hand, by setting the first coupling beam, the displacement of the mass block to the displacement of the detection frame can be amplified. The amplification of the detection frame displacement brings about an improvement in mechanical sensitivity, which can improve the signal-to-noise ratio of the gyroscope as a whole, optimize the zero-bias performance, and improve the accuracy of existing MEMS gyroscopes. On the other hand, by adopting a two-stage decoupling form, that is, the driving mode and the sensitive mode do not affect each other during the motion, the orthogonal error introduced by the process can be reduced, laying the foundation for realizing a high-performance MEMS gyroscope.

[0036] In this embodiment, the motion component includes a motion unit, which includes two drive frames 21, two mass blocks 22, and two detection frames 23. The two drive frames 21 are arranged at a distance along the Y-axis, the two mass blocks 22 are arranged at a distance along the Y-axis and are respectively connected to the two drive frames 21 by the first decoupling beam 41, and the two detection frames 23 are arranged along the X-axis and are disposed between the two mass blocks 22 and are connected by the second coupling beam 52. At the same time, the two mass blocks 22 in the same motion unit move in opposite directions, and the two detection frames 23 move in opposite directions.

[0037] In the above text, each mass block 22 is connected in parallel to two adjacent detection frames 23 in the Y-axis direction, and each detection frame 23 is bidirectionally connected to two adjacent mass blocks 22 in the Y-axis direction.

[0038] Specifically, during operation, the entire motion assembly moves along the drive mode excitation electrode 61. Figure 2 The motion of the drive frame 21 is ≥10µm, exhibiting the same frequency and amplitude reverse oscillation in the direction indicated by the arrow. Under normal operating conditions of the drive mode, the angular velocity introduces a Coriolis force onto the mass block 22. Under this force, the mass block 22 moves along the Y-axis, and its vertical compression causes the detection frame 23 to move along the X-axis. The ratio of the displacement of the mass block 22 to that of the detection frame 23 is the reciprocal of the tangent of the angle α between the first coupling beam 51 and the Y-axis, i.e., mass block 22 / detection frame 23 = 1 / tanα. The displacement amplification effect caused by the mass block 22 compressing the detection frame 23 effectively improves mechanical sensitivity and optimizes gyroscope performance.

[0039] The above technical solution provides a specific structure for a single-axis gyroscope, which can amplify the displacement of the mass block to the displacement of the detection frame, and reduce the orthogonal error introduced by the process.

[0040] In this embodiment, each of the above-mentioned mass blocks 22 is provided with a support beam 33 on the side facing the detection frame 23. The two ends of each of the above-mentioned support beams 33 along the X-axis direction are respectively connected to the two ends of the adjacent mass blocks 22 along the X-axis direction through a second decoupling beam 42. The two ends of each of the above-mentioned support beams 33 along the X-axis direction are respectively connected to the ends of the two detection frames 23 away from the center of the motion unit along the X-axis direction through a first coupling beam 51. The distance between the first end of the first coupling beam 51 and the center of the motion unit along the X-axis is greater than the distance between the second end of the first coupling beam 51 and the center of the motion unit along the X-axis.

[0041] In the above text, the second end of the first coupling beam 51 on the left side of the center of the motion component deflects to the right, and the second end of the first coupling beam 51 on the right side of the center of the motion component deflects to the left.

[0042] Through the above technical solution, the first coupling beam can place the mass block to the displacement of the detection frame.

[0043] In this embodiment, the anchor point assembly further includes a fourth anchor point 14. The motion assembly is also provided with levers 24 on both sides along the X-axis. The levers 24 are connected to the fourth anchor point 14 through a torsion beam 34. The levers 24 have a degree of freedom to rotate about the Z-axis relative to the substrate. The two ends of the levers 24 along the length direction are respectively connected to the two closest drive frames 21 along the Y-axis through a fourth coupling beam 54. The two closest drive frames 21 along the Y-axis move in opposite directions.

[0044] In the above text, the fourth anchor point 14 is a rigid fixed fulcrum fixed on the substrate. It is a dedicated rotational support structure for the lever 24, used in conjunction with the torsion beam 34 to restrict the lever's translational degree of freedom, retaining only its rotational motion capability around the Z-axis, thus providing the basic conditions for the stable torsion of the lever 24. The lever 24, through its torsional motion around the Z-axis, transmits the displacement of one side of the drive frame 21 to the reverse displacement of the other side of the drive frame 21, forcibly constraining the two drive frames 21 to achieve precise reverse synchronous motion. The torsion beam 34 is the structure connecting the lever 24 and the fourth anchor point 14, giving the lever 24 only the degree of freedom to rotate around the Z-axis, while blocking the linear displacement of the lever 24 in the X and Y axis directions. The fourth coupling beam 54 is the structure connecting the end of the lever 24 and the drive frame 21. Its function is to convert the rotational displacement of the lever 24 into the linear displacement of the drive frame 21 in the X-axis direction and realize the reverse transmission of motion.

[0045] Specifically, the driving mode excitation electrode 61 adopts a differential voltage excitation method: a set of alternating voltages is applied to the driving frame 21 on the upper side of the Y-axis to drive it to vibrate periodically in the positive direction of the X-axis; an alternating voltage with opposite phase is applied to the driving frame 21 on the lower side of the Y-axis to drive it to vibrate periodically in the negative direction of the X-axis. The technical solution is to set up a lever 24 to mechanically limit the two driving frames 21 along the Y-axis. When one end of the lever 24 swings in the positive direction of the X-axis, the corresponding driving frame 21 is driven to move in the positive direction of the X-axis through the fourth coupling beam 54; at the same time, the other end of the lever 24 swings in the negative direction of the X-axis, and the corresponding driving frame 21 is driven to move in the negative direction of the X-axis through the fourth coupling beam 54 on the other side.

[0046] By using the above technical solution and by setting lever 24, the motion symmetry and stability of the driving mode are greatly improved.

[0047] In this embodiment, the electrode assembly further includes a driving mode detection electrode 63, a sensitive mode feedback electrode (not shown in the figure), a frequency tuning electrode (not shown in the figure), and an orthogonal stiffness tuning electrode 64. The driving mode detection electrode 63 is used to detect the displacement of the driving frame 21 moving linearly along the X-axis. The sensitive mode feedback electrode is used to realize the sensitive mode closed-loop control, and its function is to apply voltage for force feedback control. The frequency tuning electrode is used to adjust the resonant frequency of the sensitive mode. The orthogonal stiffness tuning electrode 64 is used to control the orthogonal coupling stiffness, which can realize the orthogonal coupling vibration of the structure to zero.

[0048] In the above text, the function of the driving mode detection electrode 63 is to provide feedback on the motion state (amplitude, frequency, phase) of the driving frame 21, and to work with the driving mode excitation electrode 61 to achieve closed-loop control of the driving mode, thereby ensuring the stability and consistency of the driving motion.

[0049] The sensitive mode feedback electrode is used to detect the displacement signal of the detection frame 23 along the X-axis and form a feedback loop. It can adjust the working parameters of the detection mode in real time, compensate for the detection error caused by factors such as ambient temperature and vibration, and improve the long-term stability of angular velocity detection.

[0050] The frequency-tuned electrode is designed based on the principle of electrostatic stiffness tuning. By applying a DC bias voltage, the equivalent stiffness of the moving components (drive frame, mass block) is changed, thereby adjusting the resonant frequency difference between the drive mode and the detection mode, so that the two are matched to the optimal resonance state and the detection sensitivity is maximized.

[0051] The orthogonal stiffness tuning electrode 64 is a dedicated electrode used to suppress orthogonal errors. By applying a specific voltage, it compensates for the structural stiffness asymmetry caused by micro-machining process errors, eliminates orthogonal crosstalk between the driving mode motion and the detection mode, and reduces the interference of non-target signals on the detection accuracy.

[0052] Through the above technical solution, the electrode assembly consists of a driving mode excitation electrode, a driving mode detection electrode, a sensitive mode detection electrode, a sensitive mode feedback electrode, a frequency tuning electrode, and an orthogonal stiffness tuning electrode, covering the entire workflow of the gyroscope "driving-detection-feedback-tuning", and realizing precise control of motion state and signal optimization.

[0053] Example 2: See Figures 5 to 8 As shown, this invention discloses an embodiment of a single-axis MEMS gyroscope.

[0054] Everything else is the same as in Example 1, except that: In this embodiment, the motion component includes four drive frames 21, four mass blocks 22, and two detection frames 23. The four drive frames 21 are arranged in a rectangular array along the X-axis and Y-axis directions. The four mass blocks 22 are arranged in a rectangular array along the X-axis and Y-axis directions and are respectively embedded in and connected to the four drive frames 21. One detection frame 23 is located between two mass blocks 22 arranged along the Y-axis direction, and the other detection frame 23 is located between two other mass blocks 22 arranged along the Y-axis direction. At the same time, the two mass blocks 22 arranged along the X-axis move in opposite directions, the two mass blocks 22 arranged along the Y-axis move in opposite directions, and the two detection frames 23 arranged along the X-axis move in the same direction.

[0055] In the above text, the four mass blocks 22 are connected to the four drive frames 21 respectively, each mass block 22 is connected to a detection frame 23, and each detection frame 23 is connected to two adjacent mass blocks 22 along the Y-axis direction.

[0056] Specifically, during operation, the entire motion assembly moves along the drive mode excitation electrode 61. Figure 6 The arrow indicates a same-frequency, equal-amplitude, opposite-axis oscillating motion, such as... Figure 7 As shown, after the gyroscope structure is subjected to angular velocity, the Coriolis force drives the four mass blocks 22 to move along the Y-axis, with adjacent mass blocks 22 moving in opposite directions. The middle detection frame 23 is squeezed by the mass blocks 22 and moves along the X-axis, with the two central detection frames 23 moving in the same direction.

[0057] The above technical solution provides another specific structure for a single-axis gyroscope, which also has the displacement amplification effect from the mass block to the detection frame.

[0058] In this embodiment, a support beam 33 is provided on the side of the two mass blocks 22 arranged along the X-axis facing the detection frame 23. Each end of the support beam 33 along the X-axis is connected to the two ends of the adjacent mass block 22 along the X-axis by two second decoupling beams 42. Each end of the support beam 33 along the X-axis is connected to the two ends of the adjacent detection frame 23 along the X-axis by two first coupling beams 51. The distance between the first end of the first coupling beam 51 and the center of the motion component along the X-axis is less than the distance between the second end of the first coupling beam 51 and the center of the motion component along the X-axis.

[0059] In the above text, the second ends of the four first coupling beams 51 on the left side deflect to the left, and the second ends of the four first coupling beams 51 on the right side deflect to the right.

[0060] Compared with Embodiment 1, the above technical solution can improve the stability and anti-interference of the driving mode, while expanding the area of ​​the sensitive detection comb and increasing the static capacitance of the gyroscope, which is beneficial for subsequent testing and circuit matching.

[0061] Example 3: See Figures 9 to 12 As shown, this invention discloses an embodiment of a single-axis MEMS gyroscope.

[0062] Everything else is the same as in Example 1, except that: In this embodiment, the motion component includes two motion units. In each motion unit, the mass block 22 is embedded inside the drive frame 21 connected to it. The two motion units are arranged along the X-axis and adjacent drive frames 21 are connected by a third coupling beam 53. At the same time, the two aforementioned motion units move in opposite directions.

[0063] In the above, the motion units of Embodiment 1 are arrayed along the X-axis. The motion component includes two motion units, but the motion trends of the two motion units are different.

[0064] Specifically, such as Figure 10 As shown, there are four mass blocks 22 in total, one above the other, and the corresponding mass blocks 22 on the top, bottom, left, and right sides all oscillate in opposite directions with the same amplitude and frequency. Figure 11 As shown, after the gyroscope structure is subjected to angular velocity, the Coriolis force drives the four mass blocks 22 to move along the Y-axis, with adjacent mass blocks 22 moving in opposite directions. The middle detection frame 23 is squeezed by the mass blocks 22 and moves along the X-axis. The two detection frames 23 at its center move in the same direction, but in the opposite direction to the leftmost or rightmost movement.

[0065] The above technical solution provides a third type of single-axis gyroscope structure, which also has the displacement amplification effect from the mass block to the detection frame. In addition, the detection frame has differential motion, which has better resistance to external vibration or other interference.

[0066] In this embodiment, a support beam 33 is provided on the side of the two mass blocks 22 arranged along the X-axis facing the detection frame 23. Each end of each support beam 33 along the X-axis is connected to the two ends of the adjacent mass block 22 along the X-axis through two second decoupling beams 42. Each end of each support beam 33 along the X-axis is connected to the two ends of the two detection frames 23 along the X-axis through the first coupling beam 51. The distance between the first end of the first coupling beam 51 and the center of the motion unit along the X-axis is less than the distance between the second end of the first coupling beam 51 and the center of the motion unit along the X-axis.

[0067] In the above text, the second ends of the two leftmost first coupling beams 51 deflect to the left, the second ends of the two middle left first coupling beams 51 deflect to the right, the second ends of the two middle right first coupling beams 51 deflect to the left, and the second ends of the two rightmost first coupling beams 51 deflect to the right.

[0068] The above technical solution improves the resistance to acceleration and angular acceleration interference of the detection mode compared to Example 2.

[0069] Example 4: See Figures 13 to 16 As shown, this invention discloses an embodiment of a single-axis MEMS gyroscope.

[0070] Everything else is the same as in Example 1, except that: In this embodiment, the motion component includes two motion units. In each motion unit, one mass block 22 is embedded inside the drive frame 21 connected to it and located at one end of the motion component along the Y-axis. The other mass block 22 is embedded inside the drive frame 21 connected to it and located at the other end of the motion component along the Y-axis. The remaining two mass blocks 22 of the two motion units are located at the center of the motion component and are fixed to each other to form a mass group. The remaining two drive frames 21 of the two motion units are respectively located on both sides of the mass group along the X-axis. At the same time, the two aforementioned motion units move in opposite directions.

[0071] In the above text, the motion unit of Embodiment 1 is arrayed along the Y-axis, and the two mass blocks 22 are directly and rigidly connected together.

[0072] Specifically, such as Figure 14 As shown, the left and right drive frames 21 drive the mass blocks 22 to move in the same direction and at the same frequency, while the central mass block 22 and drive frames 21 move in the opposite direction and at the same frequency. Figure 15 As shown, the left and right mass blocks 22 move in opposite directions along the X-axis to the central mass block 22, and the detection frame 23 moves along the X-axis by squeezing the detection frame 23.

[0073] The above technical solution provides a fourth type of single-axis gyroscope structure, which also has the displacement amplification effect from mass block 22 to detection frame 23. In addition, it can make more efficient use of the chip area.

[0074] In this embodiment, a support beam 33 is provided on the side of each mass block 22 facing the detection frame 23. The midpoint of each support beam 33 along the X-axis direction is connected to a point on the Y-axis symmetry axis of the mass block 22 through a first decoupling beam 41. The midpoint of each support beam 33 along the X-axis direction is connected to a point on the X-axis symmetry axis of the two detection frames 23 through two first coupling beams 51. The distance between the first end of the first coupling beam 51 and the center of the motion unit along the X-axis is less than the distance between the second end of the first coupling beam 51 and the center of the motion unit along the X-axis.

[0075] In the above text, the four first coupling beams 51 of each motion unit are distributed in a rhomboid shape.

[0076] Through the above technical solutions, under the conditions of driving stability and detection resistance to acceleration and angular acceleration interference in Embodiment 3, the space of the capacitor comb teeth is further improved, the static capacitance is increased, and the mechanical sensitivity is enhanced.

[0077] Obviously, the above embodiments are merely illustrative examples for clear explanation and are not intended to limit the implementation. Those skilled in the art will recognize that other variations or modifications can be made based on the above description. It is neither necessary nor possible to exhaustively list all possible implementations here. However, obvious variations or modifications derived therefrom are still within the scope of protection of this invention.

Claims

1. A single-axis MEMS gyroscope, characterized in that, The single-axis MEMS gyroscope, having a centrally symmetric structure, includes: Substrate; An anchor point assembly, fixed on the substrate, includes a first anchor point, a second anchor point, and a third anchor point; A motion assembly includes a drive frame, a mass block, and a detection frame. The drive frame is connected to a first anchor point via a first rigid beam and has a degree of freedom of linear motion relative to the substrate along the X-axis. The mass block is connected to the drive frame via a first decoupling beam. The detection frame is connected to a second anchor point via a second rigid beam and has a degree of freedom of linear motion relative to the substrate along the X-axis. The detection frame is also connected to a support beam via a first coupling beam. The extension direction of the first coupling beam forms an acute angle with both the X-axis and Y-axis directions. The first coupling beam has a first end and a second end in its extension direction. The first end of the first coupling beam is connected to the support beam, and the second end of the first coupling beam is connected to the detection frame. The support beam is connected to the third anchor point, and the support beam is connected to the mass block via a second decoupling beam. The electrode assembly includes a driving mode excitation electrode and a sensitive mode detection electrode. The driving mode excitation electrode is used to drive the driving frame to move linearly along the X-axis direction, and the sensitive mode detection electrode is used to detect the displacement of the detection frame moving linearly along the X-axis direction. In the driving mode, the electrode assembly drives the driving frame to move linearly along the X-axis, and the driving frame drives the connected mass block to move linearly along the X-axis. In the detection mode, the mass block moves linearly along the Y-axis under the action of Coriolis force, and the mass block drives the connected detection frame to move linearly along the X-axis.

2. The single-axis MEMS gyroscope according to claim 1, characterized in that, The motion component includes a motion unit, which includes two drive frames, two mass blocks, and two detection frames. The two drive frames are arranged at a distance along the Y-axis. The two mass blocks are arranged at a distance along the Y-axis and are respectively connected to the two drive frames by the first decoupling beam. The two detection frames are arranged along the X-axis and are located between the two mass blocks and are connected by the second coupling beam. At the same time, the two mass blocks in the same motion unit move in opposite directions, and the two detection frames move in opposite directions.

3. The single-axis MEMS gyroscope according to claim 2, characterized in that, Each of the mass blocks has a support beam on one side facing the detection frame. Each support beam is connected to the two ends of the adjacent mass block along the X-axis by a second decoupling beam. Each support beam is also connected to the ends of the two detection frames away from the center of the motion unit along the X-axis by a first coupling beam. The distance between the first end of the first coupling beam and the center of the motion unit along the X-axis is greater than the distance between the second end of the first coupling beam and the center of the motion unit along the X-axis.

4. The single-axis MEMS gyroscope according to claim 2, characterized in that, The motion assembly includes two motion units. In each motion unit, the mass block is embedded inside the drive frame connected to it. The two motion units are arranged along the X-axis and adjacent drive frames are connected by a third coupling beam. At the same time, the two motion units move in opposite directions.

5. The single-axis MEMS gyroscope according to claim 4, characterized in that, A support beam is provided on one side of the detection frame for the two mass blocks arranged along the X-axis. Each end of the support beam along the X-axis is connected to the two ends of the adjacent mass block along the X-axis by two second decoupling beams. Each end of the support beam along the X-axis is connected to the two ends of the two detection frames along the X-axis by the first coupling beam. The distance between the first end of the first coupling beam and the center of the motion unit along the X-axis is less than the distance between the second end of the first coupling beam and the center of the motion unit along the X-axis.

6. The single-axis MEMS gyroscope according to claim 2, characterized in that, The motion assembly includes two motion units. In each motion unit, one mass block is embedded inside the drive frame connected to it and located at one end of the motion assembly along the Y-axis, and the other mass block is embedded inside the drive frame connected to it and located at the other end of the motion assembly along the Y-axis. The remaining two mass blocks of the two motion units are located at the center of the motion assembly and are fixed to each other to form a mass group. The remaining two drive frames of the two motion units are respectively located on both sides of the mass group along the X-axis. At the same time, the two motion units move in opposite directions.

7. The single-axis MEMS gyroscope according to claim 6, characterized in that, Each of the mass blocks has a support beam on one side facing the detection frame. The midpoint of each support beam along the X-axis is connected to a point on the Y-axis symmetry axis of the mass block through a first decoupling beam. The midpoint of each support beam along the X-axis is connected to a point on the X-axis symmetry axis of the two detection frames through two first coupling beams. The distance between the first end of the first coupling beam and the center of the motion unit along the X-axis is less than the distance between the second end of the first coupling beam and the center of the motion unit along the X-axis.

8. The single-axis MEMS gyroscope according to claim 1, characterized in that, The motion assembly includes four drive frames, four mass blocks, and two detection frames. The four drive frames are arranged in a rectangular array along the X-axis and Y-axis directions. The four mass blocks are arranged in a rectangular array along the X-axis and Y-axis directions and are respectively embedded in and connected to the four drive frames. One detection frame is located between two mass blocks arranged along the Y-axis direction, and the other detection frame is located between two other mass blocks arranged along the Y-axis direction. At the same time, the two mass blocks arranged along the X-axis move in opposite directions, the two mass blocks arranged along the Y-axis move in opposite directions, and the two detection frames arranged along the X-axis move in the same direction.

9. The single-axis MEMS gyroscope according to claim 8, characterized in that, Two mass blocks arranged along the X-axis are provided with a support beam on one side facing the detection frame. Each end of each support beam along the X-axis is connected to the two ends of the adjacent mass block along the X-axis by two second decoupling beams. Each end of each support beam along the X-axis is connected to the two ends of the adjacent detection frame along the X-axis by two first coupling beams. The distance between the first end of the first coupling beam and the center of the motion component along the X-axis is less than the distance between the second end of the first coupling beam and the center of the motion component along the X-axis.

10. The single-axis MEMS gyroscope according to any one of claims 1 to 9, characterized in that, The anchor point assembly also includes a fourth anchor point. The motion assembly has levers on both sides in the X-axis direction. The levers are connected to the fourth anchor point through a torsion beam. The levers have a degree of freedom to rotate about the Z-axis relative to the substrate. The two ends of the levers along the length direction are respectively connected to the two closest drive frames along the Y-axis direction through a fourth coupling beam. The two closest drive frames along the Y-axis direction move in opposite directions.

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