Dual-axis MEMS gyroscope

Abstract

The biaxial MEMS gyroscope comprises a substrate mechanism, an anchor point mechanism, a movement mechanism and an electrode mechanism, the anchor point mechanism is fixedly arranged on the substrate mechanism, the movement mechanism comprises driving frames, a mass block unit, a reversing unit, a transmission unit and a coupling unit, the four driving frames are evenly distributed around the center of the gyroscope, two driving frames are arranged in the 45-degree direction, and the other driving frames are arranged in the 45-degree direction. The other two driving frames are arranged in the 135-degree direction, the four mass block units are evenly distributed around the center of the gyroscope, two mass block units are arranged in the 0-degree direction, the other two mass block units are arranged in the 90-degree direction, each mass block unit comprises two mass modules which are sequentially arranged in the direction perpendicular to the direction where the mass block unit is located, and each mass module comprises a Coriolis force mass block. The reversing unit comprises two lever components, and the transmission unit comprises two outer transmission beams. According to the method, the robustness, the angular vibration resistance and the overload resistance of the gyroscope can be improved, and the inter-axis crosstalk of the gyroscope can be reduced.

Description

Technical Field

[0001] The present invention relates to the field of detection technology, and in particular to a dual-axis MEMS gyroscope. Background Art

[0002] Gyroscopes, also known as angular rate sensors, are used to detect angular velocity and angular rate around one or more axes. Gyroscopes developed using MEMS technology, namely dual-axis MEMS gyroscopes, have the advantages of high integration, small size, and low cost, and have been widely used in consumer electronics, automotive industry, aerospace and other fields.

[0003] A typical dual-axis MEMS gyroscope is mainly a capacitive resonant gyroscope. Its basic working principle is that the driving mass block drives the detection mass block to vibrate periodically back and forth through the first coupling spring under the action of electrostatic force. This mode is called driving motion or driving mode; when external angular velocity is input, due to the action of Coriolis force, the detection mass block moves in a direction orthogonal to the driving motion, which is called detection motion or detection mode; the angular velocity can be obtained by detecting the capacitance change caused by the motion of the detection mass block.

[0004] Patent US11552006 discloses a dual-axis angular rate sensor, which connects the driving modes of two sensing elements through a coupling structure. Only a single drive control circuit is required to drive the two axial sensing elements, which can reduce the packaging volume and cost. However, the two axial sensing elements of the dual-axis angular rate are independently distributed, resulting in large axial interference and common-mode interference in the sensing mode and poor accuracy. Patent CN107167123 discloses a micro-electromechanical two-axis gyroscope. This solution uses a rigid connection between four detection mass blocks arranged in two sensing axes, resulting in large axial coupling and poor seismic resistance.

[0005] How to improve the robustness, angular vibration resistance and overload resistance of the dual-axis MEMS gyroscope and reduce the inter-axis crosstalk of the gyroscope is a technical problem that needs to be solved urgently in this field. Summary of the invention

[0006] To this end, the present invention provides a dual-axis MEMS gyroscope, which can improve the robustness, anti-angular vibration and anti-overload performance of the gyroscope and reduce the inter-axis crosstalk of the gyroscope.

[0007] In order to solve the above technical problems, the present invention provides a dual-axis MEMS gyroscope, including a substrate mechanism, an anchor mechanism fixed on the substrate mechanism, a motion mechanism movably connected to the anchor mechanism, and an electrode mechanism for driving and detecting the motion mechanism, wherein the motion mechanism includes: Four driving frames are evenly arranged around the gyro center. Two of the driving frames are symmetrically arranged in the 45-degree direction, and the other two driving frames are symmetrically arranged in the 135-degree direction. The driving frames are connected to the anchor point mechanism through the first spring beam, and the driving frames have the freedom of reciprocating translation within the plane of their respective directions. Four mass units are evenly arranged around the gyro center. Two of the mass units are symmetrically arranged in the 0-degree direction, and the other two mass units are symmetrically arranged in the 90-degree direction. The mass unit includes two mass modules arranged in sequence in the vertical direction of its respective direction. The mass module includes a mass block, and each mass block is connected to the anchor point mechanism through the second spring beam. The mass block has the freedom of reciprocating swing within the plane of the z-axis direction, reciprocating swing outside the plane of the x-axis direction, and reciprocating swing outside the plane of the y-axis direction. The two mass modules of the same mass unit are connected by the first coupling spring arranged between them. Four commutation units are respectively arranged corresponding to the four driving frames. The commutation unit includes two levers, and the two levers are respectively arranged on both sides of the movement track of the corresponding driving frame. The lever is connected to the anchor point mechanism through the third spring beam, and the lever has the freedom of reciprocating swing within the plane of the z-axis direction. One end of the lever is decoupled and connected to the corresponding driving frame. Four transmission units are respectively arranged corresponding to the four mass units. The transmission unit includes two outer transmission beams, and the two outer transmission beams are respectively arranged on the sides of the two mass modules of the corresponding mass unit away from the gyro center. The two outer transmission beams of the same transmission unit are connected by the second coupling spring arranged between them. The second coupling spring is connected to the anchor point mechanism through the fourth spring beam. The outer transmission beam has the freedom of reciprocating translation within the plane of the vertical direction of its respective direction. The outer transmission beam is decoupled and connected to the mass block on the gyro center side and the adjacent lever. The coupling unit includes a coupling frame and a coupling ring. The coupling frame is arranged between the four mass units, and the coupling ring is nested inside the coupling frame. The coupling frame is connected to the coupling ring through the fifth spring beam, and the coupling ring is connected to the anchor point mechanism through the sixth spring beam. The coupling frame has the freedom of rotation in the x-axis direction, and the coupling ring has the freedom of rotation in the y-axis direction. The coupling frame is decoupled and connected to the four mass units.

[0008] Further, the lever includes a first arm segment and a second arm segment connected at an angle. The first arm segment is located on the side of the corresponding driving frame away from the mass unit, and the second arm segment is located on the side of the corresponding driving frame towards the mass unit. The intersection of the first arm segment and the second arm segment is connected to the third spring beam. The end of the first arm segment far from the third spring beam is connected to the end of the driving frame away from the gyro center through the first decoupling spring. The end of the second arm segment far from the third spring beam is connected to the adjacent outer transmission beam through the second decoupling spring. The outer transmission beam is connected to the corresponding mass block through the third decoupling spring.

[0009] Further, two levers of the same commutation unit are connected to corresponding drive frames through the same first decoupling spring.

[0010] Further, the outer transmission beam extends along the vertical direction of its direction, and one end of the outer transmission beam facing the lever is bent toward the side where the mass unit is located and then connected to the second decoupling spring.

[0011] Further, the coupling unit further includes four inner transmission beams, the four inner transmission beams are respectively arranged corresponding to the four mass units, the inner transmission beam is arranged between two mass modules of the corresponding mass unit, the inner transmission beam extends along its direction, one end of the inner transmission beam is connected to the first coupling spring, and the other end of the inner transmission beam is connected to the coupling frame through the fourth decoupling spring.

[0012] Further, each mass module includes two mass blocks arranged in sequence along its direction, and the ends of the two mass blocks of the same mass module facing the same drive frame are connected through the third coupling spring.

[0013] Further, the ends of the two mass modules of the same mass unit facing the coupling frame are connected through the fourth coupling spring, and the fourth coupling spring is connected to the coupling frame through the fifth decoupling spring.

[0014] Further, the anchor point mechanism includes a first anchor point, a second anchor point, a third anchor point, a fourth anchor point and a fifth anchor point; The first spring beam is connected to the first anchor point, the second spring beam is connected to the second anchor point, the third spring beam is connected to the third anchor point, the fourth spring beam is connected to the fourth anchor point, and the sixth spring beam is connected to the fifth anchor point.

[0015] Further, the electrode mechanism includes four first electrode units and four second electrode units. The four first electrode units are respectively arranged corresponding to the four drive frames. The first electrode unit includes a drive electrode and a drive detection electrode. The drive electrode is fixed on the substrate mechanism, and the drive electrode drives the corresponding drive frame to reciprocate in the plane. The drive detection electrode is used to detect the motion amplitude, frequency and phase of the corresponding drive frame. The four second electrode units are respectively arranged corresponding to the four mass units. The second electrode unit includes a Coriolis force detection electrode, a Coriolis force feedback electrode and an orthogonal force correction electrode. The Coriolis force detection electrode is fixed on the substrate mechanism, and the Coriolis force detection electrode detects the out-of-plane swing displacement of the corresponding mass block. The Coriolis force feedback electrode is used to start open-loop detection or closed-loop detection. There is a mass balance through hole on the mass block, and the orthogonal force correction electrode and the mass balance through hole form an orthogonal stiffness adjustment structure.

[0016] Further, the substrate mechanism includes a first substrate and a second substrate arranged on one side of the first substrate in the z-axis direction. The anchor point mechanism, the motion mechanism and the first electrode unit are all connected to the side of the first substrate facing the second substrate, and the second electrode unit is arranged on the side of the second substrate facing the first substrate.

[0017] The above technical solution of the present invention has the following advantages compared with the prior art: For the biaxial MEMS gyroscope of the present invention, on the one hand, by connecting different driving frames through a commutation unit and a transmission unit, the synchronization, robustness, and robustness of the motion of each axial driving mode are improved; on the other hand, by connecting different mass units through a coupling unit, it can ensure that the mass blocks move with the same amplitude and frequency, effectively improving the detection accuracy of the Coriolis force signal, and can also eliminate the axial interference and common-mode interference between the mass blocks when inputting the angular velocity in different detection axes, reducing the inter-axis coupling error and improving the detection accuracy of each axis; moreover, the split support, coupled connection, and differential detection scheme of multiple mass blocks can improve the anti-overload performance and signal-to-noise ratio of the gyroscope under the same volume. Description of the Drawings

[0018] In order to make the content of the present invention easier to be clearly understood, the present invention will be further described in detail below according to the specific embodiments of the present invention in conjunction with the drawings.

[0019] Figure 1 It is a schematic structural diagram of the biaxial MEMS gyroscope in Embodiment 1 of the present invention; Figure 2 It is a schematic connection diagram of the driving frame of the biaxial MEMS gyroscope in Embodiment 1 of the present invention; Figure 3 It is a schematic connection diagram of the mass blocks of the biaxial MEMS gyroscope in Embodiment 1 of the present invention; Figure 4 It is a schematic connection diagram of the coupling unit of the biaxial MEMS gyroscope in Embodiment 1 of the present invention; Figure 5 It is a schematic connection diagram of the second spring beam and the second anchor of the biaxial MEMS gyroscope in Embodiment 1 of the present invention; Figure 6 It is a schematic diagram of a driving mode of the biaxial MEMS gyroscope in Embodiment 1 of the present invention; Figure 7 It is for the biaxial MEMS gyroscope in Embodiment 1 of the present invention in Figure 6 The schematic diagram of the detection mode around the y-axis in the driving mode; Figure 8 It is for the biaxial MEMS gyroscope in Embodiment 1 of the present invention in Figure 6 The schematic diagram of the detection mode around the x-axis in the driving mode; Figure 9 It is a cross-sectional view of a mass unit of the biaxial MEMS gyroscope in Embodiment 1 of the present invention; Figure 10 It is a cross-sectional view of a mass unit of the biaxial MEMS gyroscope in Embodiment 1 of the present invention in the detection mode; Figure 11Schematic diagram of a driving mode of the biaxial MEMS gyroscope in Embodiment 1 of the present invention; Figure 12 In Embodiment 1 of the present invention, the biaxial MEMS gyroscope is in Figure 11 Schematic diagram of the detection mode around the y-axis in the driving mode; Figure 13 In Embodiment 1 of the present invention, the biaxial MEMS gyroscope is in Figure 11 Schematic diagram of the detection mode around the x-axis in the driving mode; Figure 14 Schematic diagram of a driving mode of the biaxial MEMS gyroscope in Embodiment 1 of the present invention; Figure 15 In Embodiment 1 of the present invention, the biaxial MEMS gyroscope is in Figure 14 Schematic diagram of the detection mode around the y-axis in the driving mode; Figure 16 In Embodiment 1 of the present invention, the biaxial MEMS gyroscope is in Figure 14 Schematic diagram of the detection mode around the x-axis in the driving mode; Figure 17 Schematic diagram of the structure of the biaxial MEMS gyroscope in Embodiment 2 of the present invention; Figure 18 Schematic diagram of a driving mode of the biaxial MEMS gyroscope in Embodiment 2 of the present invention; Figure 19 In Embodiment 2 of the present invention, the biaxial MEMS gyroscope is in Figure 18 Schematic diagram of the detection mode around the y-axis in the driving mode; Figure 20 In Embodiment 2 of the present invention, the biaxial MEMS gyroscope is in Figure 18 Schematic diagram of the detection mode around the x-axis in the driving mode; Figure 21 Schematic diagram of a driving mode of the biaxial MEMS gyroscope in Embodiment 2 of the present invention; Figure 22 In Embodiment 2 of the present invention, the biaxial MEMS gyroscope is in Figure 21 Schematic diagram of the detection mode around the y-axis in the driving mode; Figure 23 In Embodiment 2 of the present invention, the biaxial MEMS gyroscope is in Figure 21 Schematic diagram of the detection mode around the x-axis in the driving mode; Figure 24 Schematic diagram of a driving mode of the biaxial MEMS gyroscope in Embodiment 2 of the present invention; Figure 25 In Embodiment 2 of the present invention, the biaxial MEMS gyroscope is in Figure 24 Schematic diagram of the detection mode around the y-axis in the driving mode; Figure 26 In the second embodiment of the present invention, the detection mode schematic diagram of the biaxial MEMS gyroscope in the Figure 24 driving mode around the x-axis; Figure 27 In the third embodiment of the present invention, the structural schematic diagram of the biaxial MEMS gyroscope; Figure 28 In the third embodiment of the present invention, the connection schematic diagram of the coupling unit of the biaxial MEMS gyroscope; Figure 29 In the fourth embodiment of the present invention, the structural schematic diagram of the biaxial MEMS gyroscope.

[0020] Explanation of the reference numerals in the specification drawings: 11. First substrate; 12. Second substrate; 21. First anchor point; 22. Second anchor point; 23. Third anchor point; 24. Fourth anchor point; 25. Fifth anchor point; 31. Driving frame; 32. Mass block; 321. Mass balance through hole; 33. Lever; 331. First force arm section; 332. Second force arm section; 34. Outer transmission beam; 35. Coupling frame; 36. Inner transmission beam; 37. Coupling ring; 41. First spring beam; 42. Second spring beam; 43. Third spring beam; 44. Fourth spring beam; 45. Fifth spring beam; 46. Sixth spring beam; 51. First coupling spring; 52. Second coupling spring; 53. Third coupling spring; 54. Fourth coupling spring; 61. Driving electrode; 62. Coriolis force detection electrode; 63. Driving and detection electrode; 64. Coriolis force feedback electrode; 65. Orthogonal force correction electrode; 71. First decoupling spring; 72. Second decoupling spring; 73. Third decoupling spring; 74. Fourth decoupling spring. Detailed implementation manners

[0021] The present invention will be further described below in conjunction with the accompanying drawings and specific embodiments, so that those skilled in the art can better understand the present invention and be able to implement it, but the specific embodiments cited shall not be used as a limitation to the present invention.

[0022] Embodiment 1: Refer to Figures 1 to 5 As shown, an embodiment of the biaxial MEMS gyroscope in the present invention.

[0023] The biaxial MEMS gyroscope includes: Substrate mechanism; Anchor point mechanism, fixedly arranged on the above-mentioned substrate mechanism, including a first anchor point 21, a second anchor point 22, a third anchor point 23, a fourth anchor point 24, and a fifth anchor point 25; The motion mechanism comprises four drive frames 31, four mass units, four commutation units, four transmission units and a coupling unit. The four drive frames 31 are evenly arranged around the center of the gyroscope, wherein two of the drive frames 31 are arranged in a 45 degree direction, and the other two of the drive frames 31 are arranged in a 135 degree direction. The drive frames 31 are connected to the first anchor point 21 through a first spring beam 41. The drive frames 31 have a degree of freedom of reciprocating translation in a plane in a direction thereof. The four mass units are evenly arranged around the center of the gyroscope, wherein two of the mass units are arranged in a 0 degree direction, and the other two of the mass units are arranged in a 90 degree direction. Upward, the mass unit includes two mass modules arranged in sequence along the vertical direction of the direction in which it is located, the mass module includes a mass block 32, each of the mass blocks 32 is connected to the second anchor point 22 through a second spring beam 42, and the mass block 32 has the freedom to swing back and forth in the plane around the z-axis direction, swing back and forth out of the plane around the x-axis direction, and swing back and forth out of the plane around the y-axis direction. The two mass modules of the same mass unit are connected by a first coupling spring 51 arranged therebetween. The four reversing units are respectively arranged corresponding to the four driving frames 31. The reversing unit includes two levers 33, and the two levers 33 3 are respectively arranged on both sides of the motion track of the corresponding driving frame 31, the lever 33 is connected to the third anchor point 23 through a third spring beam 43, the lever 33 has the freedom to swing back and forth in the plane around the z-axis direction, one end of the lever 33 is decoupled and connected to the corresponding driving frame 31, the four transmission units are respectively arranged corresponding to the four mass units, the transmission unit includes two outer transmission beams 34, the two outer transmission beams 34 are respectively arranged on the side of the two mass modules of the corresponding mass unit away from the center of the gyroscope, and the two outer transmission beams 34 of the same transmission unit are connected through the third spring beam 43 arranged between the two. The outer transfer beam 34 has the degree of freedom to reciprocate in the plane along the vertical direction of the direction in which it is located, and the outer transfer beam 34 is decoupled to connect the mass block 32 on the central side of the gyroscope and the lever 33 adjacent thereto. The coupling unit includes a coupling frame 35, and the coupling frame 35 is arranged between the four mass units. The coupling frame 35 is connected to the coupling ring 37 through a fifth spring beam 45, and the coupling ring 37 is connected to the fifth anchor point 25 through a sixth spring beam 46. The coupling frame 35 has the degree of freedom to rotate around the x-axis direction, and the coupling ring 37 has the degree of freedom to rotate around the y-axis direction. The coupling frame 35 is decoupled to connect the four mass units. The electrode mechanism includes four first electrode units and four second electrode units. The four first electrode units are respectively arranged corresponding to the four driving frames 31. The first electrode unit includes a driving electrode 61, and the driving electrode 61 is fixed on the substrate mechanism. The driving electrode 61 drives the corresponding driving frame 31 to reciprocate translationally in the plane. The four second electrode units are respectively arranged corresponding to the four mass units. The second electrode unit includes a Coriolis force detection electrode 62, and the Coriolis force detection electrode 62 is fixed on the substrate mechanism. The Coriolis force detection electrode 62 detects the out-of-plane swing displacement of the corresponding mass block 32.

[0024] The 0-degree direction is parallel to the x-axis direction, and the 90-degree direction is parallel to the y-axis direction. The two mass units in the 0-degree direction detect the angular velocity in the y-axis direction, and the two mass units in the 90-degree direction detect the angular velocity in the x-axis direction.

[0025] The driving frame 31, the mass block 32, the lever 33, the outer transfer beam 34, the coupling frame 35, and the coupling ring 37 are all rigid structures. The driving electrode 61 receives the driving signal provided by the peripheral circuit and drives the corresponding driving frame 31 to perform reciprocating motion in the plane. The driving frame 31 drives the lever 33 to swing reciprocally in the plane, the lever 33 drives the outer transfer beam 34 to reciprocate translationally in the plane, and the outer transfer beam 34 drives the mass block 32 to swing reciprocally in the plane.

[0026] The structure and layout of the first spring beam 41 should ensure the freedom of movement of each driving frame 31 in its respective reciprocating motion direction and suppress the movement in other directions. The structure and layout of the second spring beam 42 should ensure the freedom of movement of the mass block 32 to swing around the set direction and suppress the movement in other directions. The third spring beam 43 should ensure the freedom of movement of the lever 33 to swing around the set direction and suppress the movement in other directions. The structure and layout of the fourth spring beam 44 should ensure the freedom of movement of the outer transfer beam 34 to translate in the set direction and suppress the movement in other directions. The structure and layout of the fifth spring beam 45 and the sixth spring beam 46 should ensure the freedom of movement of the coupling frame 35 to swing in the set direction and suppress the movement in other directions.

[0027] The lever 33 is decoupled from the driving frame 31 so that their motion modes in different motion directions do not interfere with each other. The outer transfer beam 34 is decoupled from the lever 33 so that their motion modes in different motion directions do not interfere with each other. The mass block 32 is decoupled from the outer transfer beam 34 so that their motion modes in different directions do not interfere with each other. The coupling frame 35 is decoupled from the mass block 32 so that their motion modes in different directions do not interfere with each other.

[0028] The arrangement of the first coupling spring 51 and the second coupling spring 52 can, on the one hand, effectively eliminate the coupling interference between the driving mode and the detection mode, and on the other hand, ensure that each mass block 32 moves with the same amplitude and frequency, thereby effectively improving the detection accuracy of the Coriolis force signal.

[0029] On the one hand, different drive frames are connected by levers 33 and external transfer beams 34 to improve the synchronization and robustness of each axial drive modal motion; on the other hand, different mass units are connected by coupling frames 35. The coupling frames 35 can ensure that the mass blocks 32 move with the same amplitude and frequency, effectively improving the detection accuracy of the Coriolis force signal, and can eliminate the axial interference and common-mode interference between the mass blocks 32 when the angular velocity is input in different detection axes, reduce the inter-axis coupling error, and improve the detection accuracy of each axis; moreover, the split support, coupling connection and differential detection scheme of multiple mass blocks 32 can improve the overload resistance and signal-to-noise ratio of the gyroscope under the same volume.

[0030] In this embodiment, each mass module includes a mass block 32 .

[0031] In this embodiment, the lever 33 includes a first lever arm section 331 and a second lever arm section 332 connected at an angle to each other, the first lever arm section 331 is located on the side of the corresponding driving frame 31 away from the mass unit, the second lever arm section 332 is located on the side of the corresponding driving frame 31 toward the mass unit, the intersection of the first lever arm section 331 and the second lever arm section 332 is connected to the third spring beam 43, the end of the first lever arm section 331 away from the third spring beam 43 is connected to the end of the driving frame 31 away from the center of the gyroscope through the first decoupling spring 71, the end of the second lever arm section 332 away from the third spring beam 43 is connected to the adjacent outer transfer beam 34 through the second decoupling spring 72, and the outer transfer beam 34 is connected to the corresponding mass block 32 through the third decoupling spring 73.

[0032] The length of the first lever arm section 331 is greater than that of the second lever arm section 332. The lever 33 has torque amplification and switching functions, and can obtain a larger driving displacement using a smaller driving voltage, thereby reducing power consumption.

[0033] In this embodiment, the two levers 33 of the same reversing unit are connected to the corresponding driving frame 31 through the same first decoupling spring 71 .

[0034] On the one hand, the first lever arm section 331 is longer and more labor-saving. On the other hand, the first lever arm sections 331 on both sides of the same driving frame 31 are close to each other and can be connected to the driving frame 31 through a first decoupling spring, saving springs.

[0035] In this embodiment, the outer transmission beam 34 extends in a direction perpendicular to its own direction. One end of the outer transmission beam 34 facing the lever 33 is bent towards the side where the mass unit is located and then connected to the second decoupling spring 72.

[0036] The direction of the outer transmission beam 34 is the line connecting the center position of the outer transmission beam 34 and the center of the gyroscope. The outer transmission beam 34 has an L-shaped structure, which is convenient for connecting the outer transmission beam 34 and the lever 33.

[0037] In this embodiment, the coupling unit further includes four inner transmission beams 36. The four inner transmission beams 36 are respectively arranged corresponding to the four mass units. The inner transmission beam 36 is arranged between two mass modules of the corresponding mass unit. The inner transmission beam 36 extends in its own direction. One end of the inner transmission beam 36 is connected to the first coupling spring 51, and the other end of the inner transmission beam 36 is connected to the coupling frame 35 through a fourth decoupling spring 74.

[0038] The direction of the inner transmission beam 36 is the line connecting the center position of the inner transmission beam 36 and the center of the gyroscope.

[0039] In this embodiment, the first electrode unit further includes a drive detection electrode 63, and the drive detection electrode 63 is used to detect the motion amplitude, frequency and phase of the corresponding drive frame 31.

[0040] The drive detection electrode 63 is used to detect the motion amplitude, frequency and phase of the drive part, and further acts on the drive part through an external closed-loop control circuit for frequency tuning.

[0041] In this embodiment, the second electrode unit further includes a Coriolis force feedback electrode 64 and an orthogonal force correction electrode 65. The Coriolis force feedback electrode 64 is used to start open-loop detection or closed-loop detection. A mass balance through hole 321 is provided on the mass block 32. The orthogonal force correction electrode 65 and the mass balance through hole 321 form an orthogonal stiffness adjustment structure.

[0042] The orthogonal force correction electrode 65 is directly opposite to the mass balance through hole 321. The orthogonal force correction electrode 65 generates a corresponding electrostatic negative stiffness to offset the orthogonal stiffness introduced by the processing error, so as to achieve the purpose of orthogonal correction and improve the output accuracy of the gyroscope.

[0043] In this embodiment, the substrate mechanism includes a first substrate 11 and a second substrate 12 arranged on one side of the first substrate 11 in the z-axis direction. The anchor point mechanism, the motion mechanism, and the first electrode unit are all connected to the side of the first substrate 11 facing the second substrate 12, and the second electrode unit is arranged on the side of the second substrate 12 facing the first substrate 11.

[0044] The working principle of this embodiment is introduced below.

[0045] See Figure 6 As shown, a periodic driving voltage signal is applied to the driving electrode 61. Under the action of the electrostatic force, the driving frame 31 arranged in the 45° / 135° direction makes a periodic reciprocating motion in the 45° / 135° direction. The driving force or motion is converted into a reciprocating motion in the 0° / 90° direction by squeezing or expanding the power commutation mechanism. Specifically, the driving frame 31 drives the lever 33 to make a periodic small rotation, further drives the outer transmission beam 34 to make a periodic reciprocating linear motion, and finally drives the mass block 32 to make a periodic reciprocating swing in the plane, constituting the driving mode of the gyroscope in the present invention.

[0046] See Figure 7 As shown, when the angular velocity is input in the y-axis direction, the Coriolis force causes each mass block 32 to generate a periodic reciprocating motion in the direction perpendicular to its driving direction, that is, each mass block 32 makes a periodic reciprocating rotation out of the plane, which is the motion mode of the gyroscope in the present invention for detecting the angular velocity in the Y-axis direction. The magnitude of the input angular velocity in the x-axis direction can be obtained by detecting the differential signal between the Coriolis force detection electrodes 62.

[0047] See Figure 8 As shown, when the angular velocity is input in the x-axis direction, the Coriolis force causes each mass block 32 to generate a periodic reciprocating motion in the direction perpendicular to its driving direction, that is, each mass block 32 makes a periodic reciprocating rotation out of the plane, which is the motion mode of the gyroscope in the present invention for detecting the angular velocity in the X-axis direction. The magnitude of the input angular velocity in the x-axis direction can be obtained by detecting the differential signal between the Coriolis force detection electrodes 62.

[0048] See Figure 11 As shown, the driving frame 31 arranged in the 45° / 135° direction makes an anti-phase periodic reciprocating motion in the 45° / 135° direction. The driving force or motion is converted into a reciprocating motion in the 0° / 90° direction by squeezing or expanding the power commutation mechanism; See Figure 12 and Figure 13 As shown, when the angular velocity is input in the y-axis or x-axis direction, the Coriolis force causes the mass block 32 to make a periodic reciprocating rotation out of the plane.

[0049] See Figure 14 As shown, the driving frame 31 arranged in the 45° / 135° direction makes a periodic reciprocating motion as shown in the figure in the 45° / 135° direction. The driving force or motion is converted into a reciprocating motion in the 0° / 90° direction by squeezing or expanding the power commutation mechanism; See Figure 15 and Figure 16 As shown, when the angular velocity is input in the y-axis or x-axis direction, the Coriolis force causes the mass block 32 to make a periodic reciprocating rotation out of the plane.

[0050] Embodiment 2: Refer to Figure 17 As shown, the rest is the same as Embodiment 1, except that each of the above-mentioned mass modules includes two of the above-mentioned mass blocks 32 arranged in sequence along its direction. The ends of the two mass blocks 32 of the same above-mentioned mass module facing the same above-mentioned driving frame 31 are connected by a third coupling spring 53.

[0051] Compared with Embodiment 1, the difference in this embodiment lies in the number and connection method of the mass blocks 32. In this embodiment, the mass blocks 32 adopt an array layout to increase the number of mass blocks 32. On the one hand, it increases the redundancy of the system and further improves the reliability of the holding system; on the other hand, it eliminates the inherent deviation and drift of the gyroscope and further improves the detection accuracy of the sensor.

[0052] Refer to Figure 18 As shown, a periodic driving voltage signal is applied to the driving electrode 61. Under the action of the electrostatic force, the driving frame 31 arranged in the 45° / 135° direction makes a periodic reciprocating motion along the 45° / 135° direction. The driving force or motion is converted into a reciprocating motion in the 0° / 90° direction by squeezing or expanding the power commutation mechanism. Specifically, the driving frame 31 drives the lever 33 to make a periodic small rotation, further driving the outer transmission beam 34 to make a periodic reciprocating linear motion, and finally driving the mass block 32 to make a periodic reciprocating swing in the plane, constituting the driving mode of the gyroscope in the present invention.

[0053] Refer to Figure 19 As shown, when the angular velocity is input in the y-axis direction, the Coriolis force causes each mass block 32 to generate a periodic reciprocating motion in the direction perpendicular to its driving direction, that is, each mass block 32 makes a periodic reciprocating rotation out of the plane, which is the motion mode of the gyroscope in the present invention for detecting the angular velocity in the Y-axis direction. The magnitude of the input angular velocity in the x-axis direction can be obtained by detecting the differential signal between the Coriolis force detection electrodes 62.

[0054] Refer to Figure 20 As shown, when the angular velocity is input in the x-axis direction, the Coriolis force causes each mass block 32 to generate a periodic reciprocating motion in the direction perpendicular to its driving direction, that is, each mass block 32 makes a periodic reciprocating rotation out of the plane, which is the motion mode of the gyroscope in the present invention for detecting the angular velocity in the X-axis direction. The magnitude of the input angular velocity in the x-axis direction can be obtained by detecting the differential signal between the Coriolis force detection electrodes 62.

[0055] Refer to Figure 21 As shown, the driving frame 31 arranged in the 45° / 135° direction makes an anti-phase periodic reciprocating motion along the 45° / 135° direction. The driving force or motion is converted into a reciprocating motion in the 0° / 90° direction by squeezing or expanding the power commutation mechanism; See Figure 22 and Figure 23 As shown, when the angular velocity is input in the y-axis or x-axis direction, the Coriolis force causes the mass block 32 to perform an out-of-plane periodic reciprocating rotation.

[0056] See Figure 24 As shown, the drive frame 31 arranged in the 45° / 135° direction performs the periodic reciprocating motion shown in the 45° / 135° direction, and converts the driving force or motion into a reciprocating motion in the 0° / 90° direction by squeezing or expanding the power commutation mechanism; See Figure 25 and Figure 26 As shown, when the angular velocity is input in the y-axis or x-axis direction, the Coriolis force causes the mass block 32 to perform an out-of-plane periodic reciprocating rotation.

[0057] Embodiment 3: See Figure 27 and Figure 28 As shown, the rest is the same as in Embodiment 1, except that the above-mentioned inner transfer beam is not included, and the ends of the two mass modules of the same mass unit facing the coupling frame 35 are connected by a fourth coupling spring 54, and the fourth coupling spring 54 is connected to the coupling frame 35 through a fourth decoupling spring 74.

[0058] Compared with Embodiment 1, this embodiment reduces the coupling of the mass blocks in the x and y axes and the inter-axis interference, so as to obtain a smaller cross-axis error, thereby improving the sensing performance of the sensor.

[0059] The driving mode and detection mode of this embodiment are the same as those in Embodiment 1.

[0060] Embodiment 4: See Figure 29 As shown, the rest is the same as in Embodiment 2, except that the above-mentioned inner transfer beam is not included, and the ends of the two mass modules of the same mass unit facing the coupling frame 35 are connected by a fourth coupling spring 54, and the fourth coupling spring 54 is connected to the coupling frame 35 through a fourth decoupling spring 74.

[0061] Compared with Embodiment 2, this embodiment reduces the coupling of the mass blocks 32 in the x and y axes and the inter-axis interference, so as to obtain a smaller cross-axis error, thereby improving the sensing performance of the sensor.

[0062] The driving mode and detection mode of this embodiment are the same as those in Embodiment 2.

[0063] In the schematic diagram of the detection mode of this patent, the dot in the circle represents the mass block swinging in-plane perpendicular to the paper, and the cross in the circle represents the mass block swinging out-of-plane perpendicular to the paper.

[0064] Obviously, the above embodiments are merely examples for clear illustration and not limitations on the implementation manners. For those of ordinary skill in the art, other different forms of changes or modifications can be made based on the above description. It is not necessary and impossible to enumerate all the implementation manners here. And the obvious changes or modifications derived therefrom are still within the protection scope of the present invention.

Claims

1. A dual-axis MEMS gyroscope, characterized in that, It includes a substrate mechanism, an anchor point mechanism fixedly arranged on the substrate mechanism, a motion mechanism movably connected to the anchor point mechanism, and an electrode mechanism for driving and detecting the motion mechanism. The motion mechanism includes: Four driving frames, evenly distributed around the gyro center. Two of the driving frames are symmetrically arranged in the 45-degree direction, and the other two driving frames are symmetrically arranged in the 135-degree direction. The driving frames are connected to the anchor point mechanism through the first spring beams, and the driving frames have the freedom of reciprocating translation within the plane of their respective directions; Four mass units, evenly distributed around the gyro center. Two of the mass units are symmetrically arranged in the 0-degree direction, and the other two mass units are symmetrically arranged in the 90-degree direction. The mass unit includes two mass modules arranged in sequence along the vertical direction of its respective direction. The mass module includes a mass block, and each mass block is connected to the anchor point mechanism through the second spring beam. The mass block has the freedom of reciprocating swing within the plane of the z-axis direction, reciprocating swing outside the plane of the x-axis direction, and reciprocating swing outside the plane of the y-axis direction. The two mass modules of the same mass unit are connected through the first coupling spring arranged between them; Four commutation units, respectively corresponding to the four driving frames. The commutation unit includes two levers, and the two levers are respectively arranged on both sides of the motion trajectory of the corresponding driving frame. The lever is connected to the anchor point mechanism through the third spring beam, and the lever has the freedom of reciprocating swing within the plane of the z-axis direction. One end of the lever is decoupled and connected to the corresponding driving frame; Four transmission units, respectively corresponding to the four mass units. The transmission unit includes two outer transmission beams, and the two outer transmission beams are respectively arranged on the sides of the two mass modules of the corresponding mass unit away from the gyro center. The two outer transmission beams of the same transmission unit are connected through the second coupling spring arranged between them. The second coupling spring is connected to the anchor point mechanism through the fourth spring beam. The outer transmission beam has the freedom of reciprocating translation within the plane of the vertical direction of its respective direction. The outer transmission beam is decoupled and connected to the mass block on the gyro center side and the adjacent lever; The coupling unit includes a coupling frame and a coupling ring. The coupling frame is arranged between the four mass units, and the coupling ring is nested in the coupling frame. The coupling frame is connected to the coupling ring through the fifth spring beam, and the coupling ring is connected to the anchor point mechanism through the sixth spring beam. The coupling frame has the freedom of rotation around the x-axis direction, and the coupling ring has the freedom of rotation around the y-axis direction. The coupling frame is decoupled and connected to the four mass units.

2. The biaxial MEMS gyroscope according to claim 1, characterized in that, The lever includes a first force arm section and a second force arm section connected at an angle. The first force arm section is located on the side of the corresponding driving frame away from the mass unit, and the second force arm section is located on the side of the corresponding driving frame towards the mass unit. The intersection of the first force arm section and the second force arm section is connected to the third spring beam. The end of the first force arm section far from the third spring beam is connected to the end of the driving frame away from the gyro center through the first decoupling spring. The end of the second force arm section far from the third spring beam is connected to the adjacent outer transmission beam through the second decoupling spring. The outer transmission beam is connected to the corresponding mass block through the third decoupling spring.

3. The biaxial MEMS gyroscope according to claim 2, characterized in that, The two levers of the same commutation unit are connected to the corresponding driving frame through the same first decoupling spring.

4. The biaxial MEMS gyroscope according to claim 2, characterized in that, The outer transfer beam extends in a direction perpendicular to its own direction, and the end of the outer transfer beam facing the lever bends towards the side where the mass unit is located and then connects to the second decoupling spring.

5. The dual-axis MEMS gyroscope according to claim 1, characterized in that, The coupling unit further includes four inner transfer beams, which are respectively arranged corresponding to the four mass units. The inner transfer beams are arranged between the two mass modules of the corresponding mass unit. The inner transfer beams extend in their own directions. One end of the inner transfer beam is connected to the first coupling spring, and the other end of the inner transfer beam is connected to the coupling frame through the fourth decoupling spring.

6. The biaxial MEMS gyroscope according to claim 1, wherein Each mass module includes two mass blocks arranged in sequence in its own direction. The ends of the two mass blocks of the same mass module facing the same driving frame are connected by a third coupling spring.

7. The dual-axis MEMS gyroscope according to claim 1, characterized in that, The ends of the two mass modules of the same mass unit facing the coupling frame are connected by a fourth coupling spring, and the fourth coupling spring is connected to the coupling frame through a fifth decoupling spring.

8. The biaxial MEMS gyroscope according to claim 1, characterized in that, The anchor point mechanism includes a first anchor point, a second anchor point, a third anchor point, a fourth anchor point, and a fifth anchor point; The first spring beam is connected to the first anchor point, the second spring beam is connected to the second anchor point, the third spring beam is connected to the third anchor point, the fourth spring beam is connected to the fourth anchor point, and the sixth spring beam is connected to the fifth anchor point.

9. The biaxial MEMS gyroscope according to claim 1, wherein, The electrode mechanism includes four first electrode units and four second electrode units. The four first electrode units are respectively arranged corresponding to the four driving frames. The first electrode unit includes a driving electrode and a driving detection electrode. The driving electrode is fixed on the substrate mechanism. The driving electrode drives the corresponding driving frame to reciprocate translationally in the plane. The driving detection electrode is used to detect the motion amplitude, frequency, and phase of the corresponding driving frame. The four second electrode units are respectively arranged corresponding to the four mass units. The second electrode unit includes a Coriolis force detection electrode, a Coriolis force feedback electrode, and an orthogonal force correction electrode. The Coriolis force detection electrode is fixed on the substrate mechanism. The Coriolis force detection electrode detects the out-of-plane swing displacement of the corresponding mass block. The Coriolis force feedback electrode is used to turn on open-loop detection or closed-loop detection. There is a mass balance through hole on the mass block, and the orthogonal force correction electrode and the mass balance through hole form an orthogonal stiffness adjustment structure.

10. The biaxial MEMS gyroscope according to claim 9, characterized in that, The substrate mechanism includes a first substrate and a second substrate arranged on one side of the first substrate in the z-axis direction. The anchor point mechanism, the motion mechanism, and the first electrode unit are all connected to the side of the first substrate facing the second substrate, and the second electrode unit is arranged on the side of the second substrate facing the first substrate.

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