CN104406579A - Micro-electromechanical deformable structure and triaxial multi-degree of freedom micro-electromechanical gyroscope - Google Patents

Abstract

The invention relates to a three-axis multi-degree-of-freedom micro-electromechanical gyroscope, comprising: an inner frame, a middle frame, an outer frame, and a linkage part located inside the inner frame; The linkage part is connected; two sets of drive capacitors are symmetrically distributed on both sides of the outer frame parallel to the x-axis; two sets of second detection capacitors are symmetrically distributed on both sides of the outer frame parallel to the y-axis. The three-axis multi-degree-of-freedom micro-electromechanical gyroscope of the present invention adopts a single structure design, capacitive electrostatic drive and differential capacitance detection. The influence of temperature and processing technology error is small, and good measurement accuracy and sensitivity can be achieved.

Description

MEMS deformable structure and three-axis multi-DOF MEMS gyroscope

technical field

The invention relates to microelectromechanical technology, in particular to a microelectromechanical deformable structure and a three-axis multi-degree-of-freedom microelectromechanical gyroscope.

Background technique

Micro Electro Mechanical System (MEMS), referred to as MEMS, is an emerging science and technology developed on the basis of microelectronics technology that integrates micro-machines, micro-sensors, micro-actuators, signal processing, and intelligent control.

In MEMS measurement technology, deformable connection structures are often used, and its design is related to the feasibility of the measurement scheme, and its sensitivity is also related to the accuracy of the measurement.

MEMS gyroscope is an inertial device based on MEMS technology, which is used to measure the angular velocity of object motion. It has the characteristics of small size, high reliability, low cost, and suitable for mass production, so it has broad market prospects and can be applied to a wide range of fields including consumer electronics, aerospace, automobiles, medical equipment, and weapons.

A MEMS gyroscope system usually includes a driving part and a detecting part, and its design has a certain complexity, especially when it involves a MEMS gyroscope with three-axis simultaneous measurement. At present, the three-axis gyroscope is mainly realized by the design method of orthogonal configuration of three single-axis gyroscopes or a Z-axis gyroscope and a plane detection gyroscope, but this combination is not conducive to the miniaturization of the device. Therefore, the development of a single-structure three-axis gyroscope has become an important direction in the design and development of micro-electromechanical-mechanical gyroscopes. When developing a three-axis gyroscope with a single structure, a deformable connection structure with compact structure, reduced volume and high sensitivity is more needed.

In addition, the performance of MEMS gyroscopes is greatly affected by environmental and process factors: when the ambient temperature changes, the dynamic characteristics of the sensitive structure of the gyroscope will change, causing the natural frequencies of the driving and detection modes to shift, thus changing the driving and sensing modes. The matching of the detection modes leads to the difference in the performance of the gyroscope at different ambient temperatures. And when there are errors in the processing technology, the actual dynamic characteristics of the gyroscope will also have a large deviation from the design parameters, which will affect the realization of the design performance of the gyroscope. Therefore, enhancing the robustness of the MEMS gyroscope in the design stage has also become an important content of the research and development of the MEMS gyroscope.

Contents of the invention

The purpose of the present invention is to provide a micro-electro-mechanical deformable structure with simple structure, easy realization and high sensitivity, and a three-axis multi-degree-of-freedom micro-electromechanical gyroscope with a single structure design that is less affected by temperature and process errors. Above-mentioned purpose, the present invention adopts following technical scheme:

A micro-electromechanical deformable structure, comprising: a substrate; a concentric three-layer rectangular frame located on the substrate, an inner frame, a middle frame surrounding the inner frame, and a frame surrounding the middle frame from the inside to the outside. The outer frame, the center is the origin, the inner frame, the middle frame, and the outer frame each have two sides parallel to the x-axis, and the other two sides are parallel to the y-axis; between the outer frame and the middle frame are connected by a first decoupling beam, and the first decoupling beam is arranged on both sides of the middle frame parallel to the y-axis; the middle frame and the inner frame are connected by a second decoupling beam, so The second decoupling beam is arranged on both sides of the inner frame parallel to the x-axis; the linkage part located inside the inner frame, the linkage part includes a first linkage beam, two lever beams, and two second Linkage beams; the first linkage beam and the second linkage beam are parallel to the y-axis, and the lever beams are parallel to the x-axis; the two lever beams are symmetrical about the x-axis, and are respectively linked to the first linkage The beams are connected to form a square frame structure with one end open; the two second linkage beams are symmetrical about the x-axis and are located between the lever beam and the inner frame, and one end of the second linkage beam is connected to an adjacent lever The other end of the beam is connected to the inner frame.

In a further preferred technical solution, the first decoupling beams include four Z-shaped decoupling beams symmetrical about the y-axis, one end of the Z-shaped decoupling beams is vertically connected to the side of the middle frame parallel to the y-axis, The other end is vertically connected to the side of the outer frame parallel to the y-axis.

In a further preferred technical solution, the first decoupling beams include four L-shaped decoupling beams symmetrical about the y-axis, one end of the L-shaped decoupling beams is vertically connected to the side of the middle frame parallel to the y-axis, The other end is vertically connected to the side of the outer frame parallel to the x-axis.

In a further preferred technical solution, the second decoupling beams include four Z-shaped decoupling beams symmetrical about the x-axis, one end of the Z-shaped decoupling beams is vertically connected to the side of the inner frame parallel to the x-axis, The other end is vertically connected to the side of the middle frame parallel to the x-axis.

In a further preferred technical solution, the second decoupling beams include four L-shaped decoupling beams symmetrical about the x-axis, one end of the L-shaped decoupling beams is vertically connected to the side of the inner frame parallel to the x-axis, The other end is vertically connected to the side of the middle frame parallel to the y-axis.

In a further preferred technical solution, the end of the lever beam that is not connected to the first linkage beam is a supporting end, and the supporting ends of the two lever beams are respectively fixed on the base plate through a second anchor point.

In a further preferred technical solution, the linkage part further includes two supporting beams, both of which are parallel to the y-axis; the two supporting beams are symmetrical about the x-axis and located inside the frame structure, and are connected at one end The other ends of the adjacent lever beams are respectively fixed on the base plate through a third anchor point.

In a further preferred technical solution, the end of the lever beam that is not connected to the first linkage beam is a supporting end, and each of the supporting ends of the two lever beams is fixed on the base plate through a second anchor point; The connection position between the two linkage beams and the lever beam is located in the middle of the support end of the lever beam and the connection point between the lever beam and the support beam.

In a further preferred technical solution, the linkage part further includes a third linkage beam, one end of the third linkage beam is connected to the middle part of the first linkage beam, and the other end is used for connecting with the part to be connected.

The micro-electromechanical deformable structure of the present invention, when subjected to an external force, the outer frame, the middle frame, the inner frame, and the square frame structure can all produce the effect of deformation and distortion, and also has the advantage of small deformation resistance and large deformation space, so that it can Achieve good measurement accuracy and sensitivity. The micro-electro-mechanical deformable structure of the present invention is simple and compact, which is conducive to reducing the volume of the micro-electro-mechanical system, is suitable for mass production in technology, and is less affected by temperature and processing technology errors, and is beneficial to the measurement scheme to achieve good measurement accuracy and sensitivity.

A three-axis multi-degree-of-freedom micro-electromechanical gyroscope, including the aforementioned deformable structure, and also includes: a ring-shaped detection capacitor located between the two lever beams, the center of the ring-shaped detection capacitor is facing the At the origin; the ring-shaped detection capacitor includes four lower plates fixed on the substrate and an annular upper plate facing the four lower plates and suspended above the lower plate; the four lower plates The plates are divided into two groups: the first set of lower plates are symmetrically distributed on both sides of the origin along the x-axis and the two lower plates in the group have the same shape, and the first set of lower plates and their corresponding ring-shaped upper plates The plates cooperate to form a set of first detection capacitors; the second set of lower plates are symmetrically distributed on both sides of the origin along the y-axis and the two lower plates in the group have the same shape, and the second set of lower plates and their corresponding parts The ring-shaped upper pole plate cooperates to form another group of first detection capacitors; the ring-shaped upper pole plate is fixed on the substrate through the first anchor point at the origin; the third linkage beam and the outer surface of the ring-shaped upper pole plate Along the connection; two groups of driving capacitors are symmetrically distributed on both sides of the outer frame parallel to the x-axis, and each group of driving capacitors includes movable driving electrodes and fixed driving electrodes that cooperate with each other, wherein the movable driving electrodes Connected to the outer side of the outer frame; the driving capacitor is used to provide a driving force along the y-axis direction; two sets of second detection capacitors are symmetrically distributed on both sides of the outer frame parallel to the y-axis, each group Each of the second detection capacitors includes a movable detection electrode and a fixed detection electrode that cooperate with each other, wherein the movable detection electrode is connected to the outer side of the outer frame.

In a further preferred technical solution, the annular upper plate is in the shape of a ring or a square ring.

A further preferred technical solution also includes a set of support beams located in the ring hole of the annular detection capacitance; the set of support beams includes a concentric inner ring and an outer ring, two inner ring support beams, and two inner and outer rings connected Beams, and four outer ring connecting beams; one end of the four outer ring connecting beams is respectively connected to the outer ring, and the other end is respectively connected to the inner edge of the annular upper plate; the outer ring connecting beams are divided into two One group is distributed along the x-axis, and the other group is distributed along the y-axis; one end of the two inner ring support beams is respectively connected to the inner ring, and the other end is fixed on the substrate through the first anchor point ; One end of the two inner and outer ring connecting beams is respectively connected to the inner ring, and the other end is respectively connected to the outer ring; the inner ring support beams are distributed along the y-axis and the inner and outer ring connecting beams are distributed along the x-axis, or , the inner ring supporting beams are distributed along the x-axis and the inner and outer ring connecting beams are distributed along the y-axis.

The three-axis multi-degree-of-freedom micro-electromechanical gyroscope of the present invention adopts a single structure design, capacitive electrostatic drive and differential capacitance detection, the driving method is simple, the structure is compact, and it is beneficial to reduce the volume of the gyroscope. The influence of temperature and processing technology error is small, and good measurement accuracy and sensitivity can be achieved.

Description of drawings

1 and 2 are three-dimensional schematic diagrams of the first embodiment of the three-axis multi-degree-of-freedom micro-electromechanical gyroscope of the present invention.

3 and 4 are schematic plan views of the first embodiment of the three-axis multi-degree-of-freedom micro-electromechanical gyroscope of the present invention.

Fig. 5 is a structural schematic diagram of the first embodiment of the support beam set of the present invention.

Fig. 6 is a schematic structural diagram of the second embodiment of the support beam set of the present invention.

Fig. 7 is a schematic structural diagram of the third embodiment of the support beam set of the present invention.

FIG. 8 is a schematic plan view of the second embodiment of the three-axis multi-degree-of-freedom micro-electromechanical gyroscope of the present invention.

FIG. 9 is a schematic plan view of a third embodiment of the three-axis multi-degree-of-freedom micro-electromechanical gyroscope of the present invention.

Fig. 10 is a simplified schematic diagram of the x-axis and y-axis detection system of the three-axis multi-degree-of-freedom micro-electromechanical gyroscope of the present invention.

Fig. 11 is the frequency response curves of the proof mass M2 in the driving and detecting directions during the x-axis and y-axis detection.

12 is a simplified schematic diagram of the z-axis detection system of the three-axis multi-degree-of-freedom micro-electromechanical gyroscope of the present invention.

FIG. 13 is a frequency response curve of the proof mass M4 in the driving and detecting directions during z-axis detection.

Explanation of reference signs

1 substrate;

2 ring-shaped upper plate, 6a the first set of lower plates, 6b the second set of lower plates;

7 movable driving electrodes, 4 fixed driving electrodes;

17 movable detection electrodes, 3 fixed detection electrodes;

12 inner frame, 14 middle frame, 16 outer frame;

15 the first decoupling beam, 13 the second decoupling beam;

8 first linkage beams, 9 lever beams, 11 second linkage beams, 10 support beams, 24 third linkage beams;

18 support beam group, 19 inner ring, 20 outer ring, 21 inner ring support beam, 22 inner and outer ring connecting beam, 23 outer ring connecting beam;

101 connecting beams, 102 supporting beams, 103 rings;

5a first anchor point, 5b second anchor point, 5c third anchor point.

Detailed ways

Embodiments of the present invention are described in detail below with reference to FIGS. element. The embodiments described below by referring to the figures are exemplary only for explaining the present invention and should not be construed as limiting the present invention.

Referring to Fig. 1-Fig. 4 is the first embodiment of the three-axis multi-degree-of-freedom micro-electromechanical gyroscope of the present invention, including:

Substrate 1, there is a ring-shaped detection capacitor at the center of the substrate 1, defined with the center of the ring-shaped detection capacitor as the origin O, the plane where the substrate 1 is located is a spatial Cartesian coordinate system of the xy plane, and the z-axis of the spatial Cartesian coordinate system is perpendicular to the substrate 1.

The ring-shaped detection capacitor includes four lower plates fixed on the substrate 1 and a ring-shaped upper plate 2 facing the four lower plates and suspended above the lower plate. The shape of the upper pole plate 2 matches.

The four lower pole plates can be divided into two groups: the first group of lower pole plates 6a are symmetrically distributed on both sides of the origin along the x-axis and the two lower pole plates in the group have the same shape, and the first group of lower pole plates 6a and their corresponding parts The ring-shaped upper plates cooperate to form a group of first detection capacitors A; the second group of lower plates 6b are symmetrically distributed on both sides of the origin along the y-axis and the two lower plates in the group have the same shape, and the second group of lower plates The plate 6b cooperates with the ring-shaped upper plate of its corresponding part to form the first detection capacitor B.

The annular upper plate 2 is suspended above the lower plate through a support structure, the support structure is located in the ring hole of the annular detection capacitor and connected to the inner edge of the annular upper plate 2, and the support structure passes through the first anchor point 5a at the origin Fixed on the base plate, since the support structure is only fixed at the center, the annular upper plate 2 can vibrate angularly around any axis of xyz under the action of external force.

Referring to Fig. 5, the first embodiment of the supporting structure is shown, the supporting structure includes a ring 103, three connecting beams 101, and a supporting beam 102; wherein, two connecting beams 101 are distributed along the y-axis, and the third connecting beam 101 Distributed along the x-axis and located in the positive direction of the x-axis, one end of the connecting beam 101 is connected to the ring 103, and the other end is connected to the inner edge of the annular upper plate 2; the support beam 102 is distributed along the x-axis and located in the negative direction of the x-axis , one end is connected to the ring 103, and the other end is fixed on the substrate at the origin through the first anchor point 5a. Of course, it is also possible that the third connecting beam 101 is located in the negative direction of the x-axis and the supporting beam 102 is located in the positive direction of the x-axis.

Referring to the second embodiment of the supporting structure shown in Fig. 6, the supporting structure includes a ring 103, two connecting beams 101, and two supporting beams 102; wherein, the two connecting beams 101 are distributed along the y-axis, and the connecting beams 101 One end is connected to the ring 103, and the other end is connected to the inner edge of the annular upper plate 2; two supporting beams 102 are distributed along the x-axis, one end is connected to the ring 103, and the other end is fixed to the base plate at the origin by the first anchor point 5a superior.

1-4 and FIG. 7 shows a third embodiment of the support structure, the support structure is a support beam group 18, including a concentric inner ring 19 and an outer ring 20, two inner ring support beams 21, two The inner and outer ring connecting beams 22, and four outer ring connecting beams 23; one end of the four outer ring connecting beams 23 is respectively connected with the outer ring 20, and the other end is respectively connected with the inner edge of the annular upper pole plate 2; the outer ring connecting beams 23 are divided into Two groups, wherein one group is distributed along the x-axis, and the other group is distributed along the y-axis. Four outer ring connecting beams 23 evenly divide the outer circumference of the outer ring 20; 19, and the other end is fixed on the substrate 1 through the first anchor point 5a; one end of the two inner and outer ring connecting beams 22 is respectively connected to the inner ring 19, and the other end is respectively connected to the outer ring 20; the inner ring support beam 21 along The y-axis is distributed and the inner and outer ring connecting beams 22 are distributed along the x-axis; in other embodiments, the inner ring support beams 21 are distributed along the x-axis and the inner and outer ring connecting beams 22 are distributed along the y-axis. It can be seen from the cross section of Fig. 2 that the inner edge of the annular upper pole plate 2 is connected with the supporting beam group 18 in the ring hole, and the supporting beam group 18 is fixed on the base plate by the first anchor point 5a at the origin, and the annular upper pole plate The plate 2 is suspended above the lower plate by the support of the first anchor point 5a. Since the support beam group is only fixed at the center and is slender and has certain elasticity, the annular upper plate 2 can vibrate angularly around any axis of xyz under the action of external force.

Wherein, the ring-shaped upper plate 2 in the above embodiments is all in the shape of a ring, but it should be noted that the present invention is not limited to the shape of a ring, and "ring" in the present invention refers to a structure with a hole in the center, such as The inner and outer edges are circular ring shape, the inner and outer edges are square ring shape, the outer edge is round and the inner edge is square shape, the outer edge is square and the inner edge is circular shape , the cross-shaped shape of the central opening, etc., all of which belong to equivalent embodiments within the protection scope of the present invention.

Wherein, the ring-shaped upper plate 2 and the support structure can be directly integrated, for example, formed by etching after integral patterning.

Among them, the annular variable capacitor composed of the annular detection capacitor and the supporting structure: the first set of lower plates 6a are symmetrically distributed on both sides of the origin along the x-axis, and the second set of lower plates 6b are symmetrically distributed on both sides of the origin along the y-axis distribution, so as to form a set of detection capacitors with the ring-shaped upper plate, and the ring-shaped upper plate is fixed and suspended by the anchor point 5a at the center so that it can vibrate angularly around any xyz axis. This variable capacitance design can measure deformation in two directions, and also has the advantages of small resistance and large deformation space during deformation, and can achieve good measurement accuracy and sensitivity. The structure of the annular variable capacitor of the present invention is simple and compact, which is conducive to reducing the volume of the micro-electromechanical system, and is suitable for mass production in technology. In addition to being applied to the three-axis gyroscope of the present invention, it can also be used to make a planar two-axis gyroscope. Z-axis gyroscopes and micro-actuated devices such as micro-switches.

Referring to Figures 3-4, the micro-electromechanical deformable structure includes a three-layer rectangular frame centered on the origin, and from inside to outside, there are an inner frame 12, a middle frame 14 surrounding the inner frame 12, and a middle frame surrounding the middle frame. 14 of the outer frame 16 . The centers of the inner frame 12, the middle frame 14 and the outer frame 16 are all facing the origin. Each of the inner frame 12 , the middle frame 14 , and the outer frame 16 has two sides parallel to the x-axis, and the other two sides parallel to the y-axis.

The outer frame 16 and the middle frame 14 are connected by four first decoupling beams 15, and the first decoupling beams 15 are arranged on both sides of the middle frame 14 parallel to the y-axis and about the y-axis symmetry. The first decoupling beam 15 is a Z-shaped decoupling beam, one end is vertically connected to the side of the middle frame 14 parallel to the y-axis, and the other end is vertically connected to the side of the outer frame 16 parallel to the y-axis.

The middle frame 14 and the inner frame 12 are connected by four second decoupling beams 13, and the second decoupling beams 13 are arranged on both sides of the inner frame 12 parallel to the x-axis and about the x-axis symmetry. The second decoupling beam 13 is a Z-shaped decoupling beam, one end is vertically connected to the side of the inner frame 12 parallel to the x-axis, and the other end is vertically connected to the side of the middle frame 14 parallel to the x-axis.

The linkage part located inside the inner frame 12 includes a first linkage beam 8 , two lever beams 9 , two second linkage beams 11 , two support beams 10 , and a third linkage beam 24 . The first linkage beam 8 , the second linkage beam 11 , and the support beam 10 are all arranged parallel to the y-axis, and the lever beam 9 and the third linkage beam 24 are arranged parallel to the x-axis.

The two lever beams 9 are symmetrical about the x-axis, and are respectively connected with the first linkage beam 8 to form a square frame structure with one end open. The square frame structure is located inside the inner frame 12, and the annular detection capacitor is located between the two lever beams 9;

The second linkage beam 11 is symmetrical about the x-axis and is located between the lever beam 9 and the inner frame 12. One end of the second linkage beam 11 is connected to an adjacent lever beam 9, and the other end is connected to the inner frame 12, thereby connecting the inner frame 12 and the inner frame 12. The middle frame 14 is connected, and then realizes the connection with the outer frame 16;

One end of the third linkage beam 24 is connected to the middle of the first linkage beam 8 , and the other end is connected to the outer edge of the annular upper pole plate 2 .

The two support beams 10 are symmetrical about the x-axis and are located between the frame structure and the ring-shaped detection capacitor. One end is connected to an adjacent lever beam 9 , and the other ends are respectively fixed on the substrate 1 through a third anchor point 5c.

Wherein, the end of the lever beam 9 not connected to the first linkage beam 8 is the supporting end, and the supporting ends of the two lever beams 9 are respectively fixed on the base plate 1 through a second anchor point 5b.

Wherein, the connection position between the second linkage beam 11 and the lever beam 9 is located between the support end of the lever beam 9 and the connection point between the lever beam 9 and the support beam 10 .

Wherein, the two second anchor points 5b are arranged symmetrically about the x-axis, and the two third anchor points 5c are arranged symmetrically about the x-axis. This symmetrical and fixed arrangement makes the force on the annular detection capacitor more uniform.

The micro-electromechanical deformable structure of the present invention, when subjected to an external force, the outer frame, the middle frame, the inner frame, and the square frame structure can all produce the effect of deformation and distortion, and also has the advantage of small deformation resistance and large deformation space, so that it can Achieve good measurement accuracy and sensitivity. The micro-electro-mechanical deformable structure of the present invention is simple and compact, which is conducive to reducing the volume of the micro-electro-mechanical system, is suitable for mass production in technology, and is less affected by temperature and processing technology errors, and is beneficial to the measurement scheme to achieve good measurement accuracy and sensitivity. In addition to being applied to the three-axis gyroscope of the present invention, the micro displacement amplification can also be realized at the mechanical structure level, which is beneficial to improving the detection sensitivity and signal-to-noise ratio of the sensor, and reduces the requirements of the sensitive structure on the circuit system.

Two groups of driving capacitors are symmetrically distributed on both sides of the outer frame 16 parallel to the x-axis; each group of driving capacitors includes movable driving electrodes 7 and fixed driving electrodes 4 that cooperate with each other, and the movable driving electrodes 7 and the outer frame 16 are parallel to x The sides of the shaft are connected, and the fixed driving electrode 4 is fixed on the substrate 1 .

Two groups of second detection capacitors are symmetrically distributed on both sides of the outer frame 16 parallel to the y-axis; each group of second detection capacitors includes movable detection electrodes 17 and fixed detection electrodes 3 that cooperate with each other, and the movable detection electrodes 17 and the outer frame 16 is connected to the side parallel to the y-axis, and the fixed detection electrode 3 is fixed on the substrate 1 .

Wherein, the movable driving electrode 7 and the fixed driving electrode 4 in this embodiment, as well as the movable detecting electrode 17 and the fixed detecting electrode 3 are all comb-shaped electrodes, and the detection is performed based on the change of the overlapping length between the plates. However, the present invention is not limited thereto, and the driving capacitor and the second detecting capacitor may also be planar capacitors, which are detected based on changes in the gap between the plates.

The working principle of the first embodiment of the three-axis multi-degree-of-freedom micro-electromechanical gyroscope of the present invention is as follows:

The driving capacitor is used to provide a driving force along the y-axis direction. When driven by the outside, the outer frame 16, the movable driving electrode 7 and the movable detection electrode 17 move linearly along the y-axis direction, driving the middle frame 14, the inner The frame 12 moves linearly along the y-axis direction, and at the same time, the second linkage beam 11 drags the lever beam 9 to move linearly along the y-axis direction. The lever beam 9 is equivalent to a lever, so it will drive the first linkage beam 8 to move linearly along the y-axis direction. Movement, wherein the movement direction of the first linkage beam 8 is opposite to that of the second linkage beam 11. Since the first linkage beam 8 is connected to the outer edge of the annular upper pole plate 2 through the third linkage beam 24, and the annular upper pole plate 2 is fixed on the base plate 1 at the origin via the first anchor point 5a through the support beam group 18, therefore The ring-shaped upper plate 2 will rotate around the first anchor point 5a under the drag of the first linkage beam 8, that is, make angular vibration around the z-axis. Therefore, the driving motion includes the linear motion of the three-layer frame along the y-axis direction and the angular vibration of the annular upper plate 2 around the z-axis.

When the gyroscope rotates around the x-axis, due to the Coriolis force, the annular upper plate 2 will vibrate angularly around the y-axis, which will cause the change in the distance between the first group of lower plates 6a and the substrate 1, resulting in the first Detect the change of capacitance A, which is proportional to the angular velocity of the gyroscope around the x-axis, so it can be used to measure the x-axis angular velocity. At this time, the first detection capacitance B and the second detection capacitance are not affected, or the influence is very small and can be ignored.

When the gyroscope rotates around the y-axis, due to the Coriolis force, the ring-shaped upper plate 2 will vibrate angularly around the x-axis, which will cause the change of the distance between the second set of lower plates 6b and the substrate 1, resulting in the first Detect the change of capacitance B, which is proportional to the angular velocity of the gyroscope around the y-axis, so it can be used to measure the y-axis angular velocity. At this time, the first detection capacitor A and the second detection capacitor are not affected, or the influence is very small and can be ignored.

When the gyroscope rotates around the z-axis, the ring-shaped upper plate 2 which vibrates angularly around the z-axis is not affected. Due to the effect of the Coriolis force, the outer frame 16, the middle frame 14, and the inner frame 12 are subjected to a force in the x-axis direction, but since the lever beam 9 is rigid and one end is fixed, the movement of the inner frame 12 in the x-axis direction is limited, it will not affect the ring-shaped upper plate 2, so the ring-shaped detection capacitance will not be affected. Due to the decoupling effect of the first decoupling beam 15, the movement of the outer frame 16 in the x-axis direction will not be restricted. Therefore, the outer frame 16 will move linearly along the x-axis direction, resulting in the second detection capacitance (by the movable detection electrode) 17 and the fixed detection electrode 3), the capacitance change reflects the angular velocity of the gyroscope around the z-axis, so it can be used to detect the angular velocity of the z-axis.

In this embodiment, the lever beam 9 is not only connected to the first linkage beam 8, the second linkage beam 11 and the support beam 10, but also fixed on the base plate 1 (that is, at the second anchor point 5b) through the support end, and the second The connecting position of linkage beam 11 and lever beam 9 is located in the middle of the support end of lever beam 9 and the connection point of lever beam 9 and support beam 10. This situation is beneficial to the movement of the three-layer frame, because: the lever After the original free end of the beam 9 is fixed as the support end, the lever beam 9 between the second anchor point 5b and the support beam 10 is equivalent to the support beam at both ends, and the deformation mode of this section of the lever beam 9 is that the two ends of the middle drum are fixed. form, its state perpendicular to the y-axis will not change. At this time, if the second linkage beam 11 is in its middle position, the second linkage beam 11 will not be subjected to torque and cause rotation, and if it deviates from the middle position, the lever beam 9 will be vertical The state of the y-axis will change, and this deflection will affect the motion mode of the three-layer frame.

Referring to FIG. 8 , it is a schematic plan view of the second embodiment of the three-axis multi-degree-of-freedom micro-electromechanical gyroscope of the present invention. The difference from the first embodiment mainly lies in the shape and connection method of the first decoupling beam 15 . In the second embodiment: the outer frame 16 and the middle frame 14 are connected by four first decoupling beams 15, and the first decoupling beams 15 are arranged on both sides of the middle frame 14 parallel to the y-axis and symmetrical about the y-axis; The first decoupling beam 15 is an L-shaped decoupling beam, one end is vertically connected to the side of the middle frame 14 parallel to the y-axis, and the other end is vertically connected to the side of the outer frame 16 parallel to the x-axis.

Referring to FIG. 9 , it is a schematic plan view of the third embodiment of the three-axis multi-degree-of-freedom micro-electromechanical gyroscope of the present invention. The difference from the second embodiment mainly lies in the shape and connection method of the second decoupling beam 13 . In the third embodiment: the middle frame 14 and the inner frame 12 are connected by four second decoupling beams 13, and the second decoupling beams 13 are arranged on both sides of the inner frame 12 parallel to the x-axis and are symmetrical about the x-axis; The second decoupling beam 13 is an L-shaped decoupling beam, one end is vertically connected to the side of the inner frame 12 parallel to the x-axis, and the other end is vertically connected to the side of the middle frame 14 parallel to the y-axis.

The present invention specially designs a three-layer rectangular frame structure, the inner frame and the middle frame are connected by a Z-shaped or L-shaped second decoupling beam, and the middle frame and the outer frame are connected by a Z-shaped or L-shaped first decoupling beam. The decoupling beams are connected, wherein the first decoupling beam limits the relative movement of the outer frame 16 and the middle frame 14 in the y-axis direction, and the second decoupling beam limits the movement of the middle frame 14 and the inner frame 12 in the x-axis direction. Relative motion, this special design can enhance the robustness of the gyroscope, specifically, it has the following beneficial effects:

Fig. 10 is a simplified schematic diagram of the x- and y-axis detection system of the three-axis multi-degree-of-freedom micro-electromechanical gyroscope of the present invention, and Fig. 11 is the frequency response curve of the proof mass M2 in the driving and detection directions during the x- and y-axis detection.

Referring to Fig. 10, since the first decoupling beam 15 limits the relative movement of the outer frame 16 and the middle frame 14 in the y-axis direction, the combination of the outer frame 16 and the middle frame 14 can be simplified as a mass M1, and the inner frame The combination of 12 and the ring-shaped upper plate 2 and each tie beam connecting the two can be simplified into a proof mass M2. Referring to FIG. 11 , when the mass M1 is driven by a driving force, the proof mass M2 is driven to move in the driving direction, wherein the mass M1 can only move in the driving direction, and the proof mass M2 can move in both the driving and detection directions. On the driving motion frequency response curve of the proof mass M2, when the driving frequency is in the flat section between the two peaks of the driving frequency response curve, the entire system realizes power amplification, that is, the motion amplitude of the mass M1 reaches the minimum, and the proof mass M1 The amplitude of the movement of M2 reaches the maximum. And at this time, the change of resonance frequency caused by temperature and processing error has little influence on the frequency response of the driving flat section, so the change of the gyro driving motion is very small, thereby improving the stability of the gyro driving work. Further, at the same time, the natural frequency of the detection mode of the detection mass M2 in the detection direction is designed in the flat section between the two peaks of the driving frequency response, so that the matching of the driving and detection frequencies can be realized, and the detection accuracy of the gyroscope can be improved. and sensitivity performance.

FIG. 12 is a simplified schematic diagram of the z-axis detection system of the three-axis multi-degree-of-freedom micro-electromechanical gyroscope of the present invention, and FIG. 13 is the frequency response curve of the proof mass M4 in the driving and detection directions during z-axis detection.

Referring to the left diagram of FIG. 12 , the driving motion power amplification principle of the z-axis detection system is the same as that in FIG. 7 because it is the same driving motion. Referring to the right figure of Fig. 12, when the gyro structure rotates around the z-axis, the inner frame 12 is driven by the Coriolis force in the x-axis, and the second decoupling beam 13 limits the movement of the inner frame 12 and the middle frame 14 in the x-axis direction. Therefore, the inner frame 12 and the outer frame 14 are equivalent to two fixed masses, which can be simplified as a mass M3. The connection between the outer frame 16 and the middle frame 14 is equivalent to the spring connection in the x-axis, and the outer Frame 16 is reduced to proof mass M4. As shown in Figure 13, the proof mass M3 is driven by the Coriolis force to move the detection mass M4 in the detection direction. When the frequency of the Coriolis force is in the straight section between the two peaks of the detection mode curve, the movement displacement of the proof mass M4 is the largest. The movement displacement of the mass block M3 is the smallest, that is, the power amplification is realized. At the same time, the structure also has the characteristics of being less affected by temperature and process errors, which is conducive to improving the stability of the system's drive and detection motion, as well as the accuracy and sensitivity of gyroscope detection.

The three-axis multi-degree-of-freedom micro-electromechanical gyroscope of the present invention adopts a single structure design, capacitive electrostatic drive and differential capacitance detection, the driving method is simple, the structure is compact, and it is beneficial to reduce the volume of the gyroscope. The influence of temperature and processing technology error is small, and good measurement accuracy and sensitivity can be achieved.

The structure, features and effects of the present invention have been described in detail above based on the embodiments shown in the drawings. The above are only preferred embodiments of the present invention, but the present invention does not limit the scope of implementation as shown in the drawings. Changes made to the idea of the present invention, or modifications to equivalent embodiments that are equivalent changes, and still within the spirit covered by the description and illustrations, shall be within the scope of protection of the present invention.

Claims (12)

1. a micro electronmechanical deformable structure, is characterized in that, comprising:

Substrate;

Be positioned at the concentric three layers of rectangular frame on described substrate, from inside to outside be followed successively by inner frame, surround the central frame of described inner frame and surround the outside framework of described central frame, described center is initial point, described inner frame, central frame and outside framework respectively have two limits to be parallel to x-axis, and two other limit is parallel to y-axis;

Connected by the first decoupling zero beam between described outside framework and described central frame, described first decoupling zero beam is arranged at the both sides that described central frame is parallel to y-axis; Connected by the second decoupling zero beam between described central frame and described inner frame, described second decoupling zero beam is arranged at the both sides that described inner frame is parallel to x-axis;

Be positioned at the linkage portion of described inner frame inside, described linkage portion comprises the first interlock beam, two lever beams and two second interlock beams; Described first interlock beam and described second interlock beam are all parallel to y-axis, and described lever beam is all parallel to x-axis;

Article two, described lever beam is symmetrical about x-axis, and the beam that links with described first is respectively connected the frame structure to form one end open;

Article two, described second interlock beam is symmetrical and between described lever beam and described inner frame, one end of described second interlock beam connects a contiguous lever beam, and the other end connects described inner frame about x-axis.

2. deformable structure as claimed in claim 1, is characterized in that:

Described first decoupling zero beam comprises four Z-type decoupling zero beams about y-axis symmetry, and one end of described Z-type decoupling zero beam vertically connects the side that described central frame is parallel to y-axis, and the other end vertically connects the side that described outside framework is parallel to y-axis.

3. deformable structure as claimed in claim 1, is characterized in that:

Described first decoupling zero beam comprises four L-type decoupling zero beams about y-axis symmetry, and one end of described L-type decoupling zero beam vertically connects the side that described central frame is parallel to y-axis, and the other end vertically connects the side that described outside framework is parallel to x-axis.

4. deformable structure as claimed in claim 1, is characterized in that:

Described second decoupling zero beam comprises four Z-type decoupling zero beams about x-axis symmetry, and one end of described Z-type decoupling zero beam vertically connects the side that described inner frame is parallel to x-axis, and the other end vertically connects the side that described central frame is parallel to x-axis.

5. deformable structure as claimed in claim 1, is characterized in that:

Described second decoupling zero beam comprises four L-type decoupling zero beams about x-axis symmetry, and one end of described L-type decoupling zero beam vertically connects the side that described inner frame is parallel to x-axis, and the other end vertically connects the side that described central frame is parallel to y-axis.

6. deformable structure as claimed in claim 1, is characterized in that:

Described lever beam one end that beam is connected of not linking with described first is support end, and the support end of described two lever beams is respectively fixed on described substrate by one second anchor point.

7. deformable structure as claimed in claim 1, is characterized in that:

Described linkage portion also comprises two brace summers, and described two brace summers are all parallel to y-axis;

Described two brace summers are symmetrical and be positioned at inside described frame structure about x-axis, and one end connects a contiguous lever beam, and the other end is respectively fixed on described substrate by one the 3rd anchor point.

8. deformable structure as claimed in claim 7, is characterized in that:

Described lever beam one end that beam is connected of not linking with described first is support end, described two lever beam support ends be respectively fixed on described substrate by one second anchor point;

The link position of described second interlock beam and lever beam is positioned in the middle of the support end of lever beam and the tie point of lever beam and described brace summer.

9. the deformable structure as described in any one of claim 1-8, is characterized in that:

Described linkage portion also comprises the 3rd interlock beam, and one end of described 3rd interlock beam connects the middle part of described first interlock beam, and the other end is used for being connected with to be connected.

10. three axle multiple degrees of freedom micro-electro-mechanical gyroscopes, is characterized in that, comprise deformable structure as claimed in claim 9, also comprise:

Annular Detection capacitance between two described lever beams, the center of described annular Detection capacitance is just to described initial point place;

Described annular Detection capacitance comprises and is fixed on four bottom crowns on substrate and just to described four bottom crowns and the annular top crown be suspended in above described bottom crown;

Described four bottom crowns are divided into two groups: first group of bottom crown along x-axis in the symmetria bilateralis distribution of initial point and two bottom crown shapes in group are identical, and described first group of bottom crown matches with the annular top crown of its corresponding part formation one group of first Detection capacitance; Second group of bottom crown is identical along two the bottom crown shapes of y-axis in the symmetria bilateralis distribution of initial point and in group, and described second group of bottom crown matches with the annular top crown of its corresponding part and form another and organize the first Detection capacitance; Described annular top crown is fixed on substrate at initial point place by the first anchor point;

Described 3rd interlock beam is connected with the outer of described annular top crown;

Two groups drive electric capacity, and be symmetrically distributed in the both sides that described outside framework is parallel to x-axis, often organize described driving electric capacity and all comprise the movable drive electrode and fixed drive electrode of working in coordination, wherein said movable drive electrode is connected with the outer side edges of described outside framework; Described driving electric capacity is for providing driving force along the y-axis direction;

Two group of second Detection capacitance, be symmetrically distributed in the both sides that described outside framework is parallel to y-axis, often organize described second Detection capacitance and all comprise the movable detecting electrode and fixed test electrode of working in coordination, wherein said movable detecting electrode is connected with the outer side edges of described outside framework.

11. three axle multiple degrees of freedom micro-electro-mechanical gyroscopes as claimed in claim 10, is characterized in that:

Described annular top crown is toroidal or square ring-shaped.

12. three axle multiple degrees of freedom micro-electro-mechanical gyroscopes as claimed in claim 10, is characterized in that:

Also comprise the brace summer group being positioned at described annular Detection capacitance annular distance;

Described brace summer group comprises concentric interior annulus and outer toroid, two inner ring brace summers, two inner and outer ring tie-beams and four outer shroud tie-beams;

One end of described four outer shroud tie-beams is connected with outer toroid respectively, and the other end is connected with edge in described annular top crown respectively; Described outer shroud tie-beam is divided into two one group, and wherein one group distributes along x-axis, and another group distributes along y-axis;

One end of described two inner ring brace summers is connected with interior annulus respectively, and the other end is fixed on described substrate by described first anchor point;

One end of described two inner and outer ring tie-beams is connected with interior annulus respectively, and the other end is connected with outer toroid respectively;

Described inner ring brace summer along y-axis distribution and described inner and outer ring tie-beam distribute along x-axis, or, described inner ring brace summer along x-axis distribution and described inner and outer ring tie-beam distribute along y-axis.