A composite nonlinear seismic isolation device and method for a MEMS gyroscope

Abstract

The application discloses a composite nonlinear vibration isolation and damping device and method for MEMS gyroscopes. The device comprises a first moving component for fixing a MEMS gyroscope assembly, a second moving component fixed to a carrier, and a damping elastic support and a magnet assembly arranged between the two moving components along a predetermined direction; the damping elastic support bears static load, vibration isolation, reset and energy dissipation; the upper and lower magnets of the magnet assembly are oppositely arranged on the two moving components and have the same polarity, and a predetermined initial gap is kept when static balance; the magnet assembly does not bear load under static load and small amplitude working conditions, the magnetic repulsion force sharply increases in a nonlinear manner when the magnetic gap is reduced by impact, the maximum stroke is limited in a non-contact manner, and the residual vibration is attenuated by the damping elastic support after impact. The application considers normal working condition low stiffness vibration isolation and large impact limiting protection, and reduces the transient acceleration peak value and structural stress transmitted to the MEMS gyroscope.

Description

Technical Field

[0001] This invention relates to the field of vibration and shock protection technology for inertial devices in microelectromechanical systems (MEMS), specifically to a composite nonlinear vibration reduction and isolation device and method for MEMS gyroscopes. Background Technology

[0002] MEMS gyroscopes are typically rigidly connected to a carrier via a housing, printed circuit board, or mounting base. When the carrier is subjected to impacts such as drops, collisions, or launches, the impact energy is directly transferred to the gyroscope assembly through the mounting interface. This causes the package, solder joints, and sensitive structures to experience significant transient acceleration and stress, which may lead to short-term output saturation, sudden zero-bias changes, decreased repeatability, and in severe cases, structural damage.

[0003] In existing technologies, elastic supports such as rubber pads, rubber rods, or metal springs are commonly used to reduce vibration in MEMS gyroscopes. However, these supports typically employ a single stiffness to simultaneously bear both static and impact loads: with lower stiffness, the vibration isolation effect is good under normal operating conditions, but under large impacts, the support stroke becomes too large, easily causing internal collisions or exceeding the structural allowable space; with higher stiffness, although the impact stroke can be limited, the vibration isolation effect under normal operating conditions deteriorates significantly. In other words, a single near-linear support cannot simultaneously achieve low-stiffness vibration isolation under normal operating conditions, static load bearing, and limiting protection under large impacts.

[0004] Existing technologies also use the magnetic repulsion generated by arranging permanent magnets with opposite poles to buffer vibrations. However, the repulsion of permanent magnets is essentially a conservative restoring force and does not directly dissipate vibration energy. If only magnetic repulsion is relied upon without independent energy dissipation components, the system may continue to oscillate after an impact, which is not conducive to the MEMS gyroscope quickly recovering to a stable working state after an impact.

[0005] Therefore, how to solve the contradiction between the support stiffness requirements of MEMS gyroscopes under normal vibration and large impact conditions, and at the same time effectively suppress residual vibration after impact, is a technical problem that urgently needs to be solved in this field. Summary of the Invention

[0006] To address the deficiencies or shortcomings of the existing technology, the present invention aims to provide a composite nonlinear vibration reduction and isolation device and method for MEMS gyroscopes, thereby solving the following technical problems: (1) Solve the problem of contradictory support stiffness requirements of MEMS gyroscopes under normal vibration and large impact conditions; (2) The magnet is basically not subjected to load during static load and normal small amplitude stage, and has little impact on small signal equivalent stiffness, while automatically providing rapidly growing nonlinear impact resistance when the relative displacement increases; (3) Limit the maximum stroke of the gyroscope assembly without the upper and lower magnets coming into contact or rigid impact, thereby reducing the peak transient acceleration and structural stress transmitted to the MEMS device; (4) The static load, reset and energy dissipation are borne by the damped elastic support, which suppresses the continuous oscillation after impact that may be caused by the magnetic nonlinear restoring force.

[0007] To achieve the above objectives, the present invention adopts the following technical solution: A composite nonlinear vibration damping and isolation device for a MEMS gyroscope includes: a first moving component for fixedly mounting a MEMS gyroscope assembly; a second moving component disposed opposite to the first moving component for fixed connection to a carrier; at least one damping elastic support member disposed between the first moving component and the second moving component along a predetermined direction, the two ends of the damping elastic support member being fixedly connected to the first moving component and the second moving component respectively, forming a first bearing path that always bears load; a magnet assembly including an upper magnet fixed to the side of the first moving component facing the second moving component and a lower magnet fixed to the side of the second moving component facing the first moving component, the upper magnet and the lower magnet being coaxially arranged along the predetermined direction, the magnetization axes of the upper magnet and the lower magnet being both along the predetermined direction, and their opposing working surfaces being magnetic poles of the same name, forming a second bearing path, the second bearing path being structurally parallel to the first bearing path; wherein, in a static equilibrium state, a predetermined initial gap is maintained between the working surfaces of the upper magnet and the lower magnet.

[0008] It should be noted that the damping elastic support component mentioned in this invention refers to a support element that combines elastic recovery capability and damping energy dissipation capability, including but not limited to viscoelastic material support components such as rubber support components, silicone damping pads, and polyurethane elastomer support components. The first moving component and the second moving component refer to two mounting components capable of relative motion along the predetermined direction under external excitation. In one specific embodiment, the first moving component is a carrier plate for mounting a MEMS gyroscope assembly, and the second moving component is a base for fixed connection with the carrier. The predetermined direction is the direction in which vibration reduction and isolation are required, preferably a vertical direction, but can also be determined as another direction according to the actual mounting posture and vibration isolation requirements of the MEMS gyroscope; this specification describes the embodiments with the predetermined direction as vertical, the first moving component as a carrier plate, and the second moving component as a base.

[0009] Furthermore, the damping elastic support is a rubber support, a silicone damping pad, or a polyurethane elastomer support. Further, the damping elastic support is a cylinder made of natural rubber with a Shore A hardness of 80, and the damping elastic support is fixedly connected to the first moving component and the second moving component by vulcanization bonding.

[0010] Furthermore, there are multiple damping elastic support members and one or more magnet assemblies. The multiple damping elastic support members and the multiple magnet assemblies are symmetrically distributed about a centerline passing through the center of gravity of the MEMS gyroscope assembly and along the predetermined direction, so that the resultant force of the restoring force generated by the damping elastic support members and the magnet assemblies passes through the center of gravity of the MEMS gyroscope assembly.

[0011] Furthermore, the initial gap satisfy: ,in, This represents the maximum allowable impact compressive displacement of the structure. A safety gap is provided to prevent the upper magnet from contacting the lower magnet. The total stiffness of the damping elastic support is... , These are the magnetic dipole moments of the upper magnet and the lower magnet, respectively. The vacuum permeability. Furthermore, the safety gap... The diameter is taken as 0.3 mm to 0.8 mm. Further, the height of the damping elastic support member... Not less than ,in The thickness of a single magnet is determined to ensure that the installation space meets the minimum magnetic clearance requirement; and the height of the damping elastic support is... Not greater than ,in The peak impact force is measured through impact simulation or testing. The elastic modulus of the damping elastic support is given. The total cross-sectional area of ​​the damping elastic support member is [missing information]. It is the instability coefficient, used to prevent the damping elastic support from becoming unstable and failing during large-amplitude vibrations.

[0012] Furthermore, there are five damping elastic support members, four of which are located in the four corner areas of the first moving member and one in the central area of ​​the first moving member; there are two sets of magnet assemblies, and the two sets of magnet assemblies are symmetrically arranged with respect to the projection of the center of gravity of the MEMS gyroscope assembly onto the first moving member.

[0013] Furthermore, both the first moving component and the second moving component are made of non-magnetic materials; the device also includes a magnetic shield for controlling the magnetic field distribution in the mounting area of ​​the MEMS gyroscope assembly, and / or the magnet assembly adopts a symmetrical magnetic circuit structure.

[0014] Furthermore, the device also includes a soft limiting block disposed between the first moving member and the second moving member. The soft limiting block has a gap between itself and its opposite surface, and only contacts the opposite surface when the first moving member reaches its limit displacement, thus providing fail-safe protection.

[0015] The present invention also provides a composite nonlinear vibration reduction and isolation method for MEMS gyroscopes, which employs the above-mentioned composite nonlinear vibration reduction and isolation device for MEMS gyroscopes and includes the following steps: (1) Based on the maximum allowable impact compression displacement of the structure With safety clearance Determine the initial gap The lower limit makes According to the total stiffness of the damping elastic support member and the magnetic dipole moments of the upper magnet and the lower magnet , Determine the initial gap The upper limit is such that the absolute value of the magnetic stiffness of the magnet assembly in static equilibrium is not less than 10% of the total stiffness of the damping elastic support; (2) Fix the MEMS gyroscope assembly to the first motion component, fix the second motion component to the carrier, and the damping elastic support generates pre-compression and establishes static balance under static load. The upper magnet and the lower magnet maintain a predetermined initial gap, and all or most of the static load is borne by the damping elastic support. (3) When the carrier generates normal small-amplitude vibration, the first moving component makes small-amplitude movement near the static equilibrium position, and the damping elastic support provides low stiffness and damped vibration isolation. The magnetic repulsion force increment generated by the magnet assembly is approximately zero. (4) When the impact compresses the first moving member toward the second moving member, the damping elastic support first increases the restoring force and dissipates some energy; as the magnetic gap decreases, the magnetic repulsion between the upper magnet and the lower magnet increases nonlinearly inversely proportional to the fourth power of the magnetic gap, which, together with the restoring force of the damping elastic support, limits the maximum stroke of the first moving member, avoiding contact between the upper magnet and the lower magnet and rigid impact between the first moving member and the second moving member; (5) After the peak impact, the magnetic repulsion and elastic restoring force push the first moving component back to the static equilibrium position. The magnetic repulsion weakens rapidly as the magnetic gap increases and it stops bearing the load. The residual vibration is attenuated by the hysteresis energy dissipation of the damping elastic support, and the first moving component returns to the static equilibrium position.

[0016] Compared with the prior art, the present invention has the following beneficial effects: (1) This invention does not simply arrange the like-pole opposing magnets and damping elastic supports side by side. Instead, it constructs a magnetic-elastic dual load-bearing path with a clear initial gap and functional division of labor, based on the different requirements of MEMS gyroscopes for normal small vibrations, large impacts, and post-impact residual vibrations: the damping elastic support path exists in all working stages, undertaking static loads, small amplitude vibration isolation, reset, and energy dissipation; the magnet support path is approximately non-involved in static loads and normal small amplitude stages, and only intervenes continuously and non-linearly when the impact compression displacement increases and the magnetic gap decreases significantly. This solves the problem that a single approximately linear support cannot simultaneously take into account both low stiffness vibration isolation under normal working conditions and large impact load-bearing limit. Moreover, after the impact displacement increases, a second load-bearing path can be automatically formed without sensors, power supplies, or controllers, resulting in a simple structure and high reliability.

[0017] (2) When the impact compresses the first moving component toward the second moving component, the magnetic gap gradually decreases, the magnetic repulsion force and magnetic tangential stiffness increase nonlinearly with displacement, and together with the restoring force of the damping elastic support, they bear the impact load. This can gradually improve the impact resistance and limit the maximum stroke without relying on the contact between the upper and lower magnets, thus avoiding the risk of transient load change, acceleration spike, and damage to the packaging, solder joint stress and sensitive structure caused by hard limit collision.

[0018] (3) The damping elastic support generates hysteresis loss during compression and rebound, which solves the problem that although the restoring force is strong when magnetic repulsion is used alone, it may continue to oscillate after impact: the magnet provides non-contact progressive stiffening and reset effect, and the damping elastic support dissipates vibration energy, thereby shortening the duration of residual vibration after impact and enabling the first moving component to quickly return to a stable working position.

[0019] (4) Multiple sets of magnets and damping elastic supports are symmetrically arranged about the center line of the vibration-isolated part, so that the resultant force of each set of restoring forces passes through the center of gravity of the MEMS gyroscope component as much as possible. This avoids the tilting, additional rotation or local stress concentration of the first moving component caused by uneven force distribution at multiple support points. It is beneficial to keep the first moving component parallel to the second moving component under the design condition that only the response in the predetermined direction is considered, and reduce the additional overturning moment and attitude disturbance caused by the impact.

[0020] (5) The vibration isolation layer is directly set at the lower part of the first motion component of the MEMS gyroscope. The intervention displacement and maximum impact resistance can be adjusted by the magnet specifications, the number of magnet groups, the effective opposing area and the initial gap. The magnetic field influence of the sensor installation area can be controlled by using a non-magnetic mounting base, symmetrical magnetic circuit or magnetic shielding. The device is a passive structure and does not require external power supply. It can be matched in a relatively compact space according to different gyroscope masses, normal vibration frequency bands and designed impact strokes, and has good engineering adaptability. Attached Figure Description

[0021] Figure 1 This is a front view of the magnetic-rubber composite nonlinear vibration reduction and isolation device according to an embodiment of the present invention; Figure 2 This is a cross-sectional view of section AA of the magnetic-rubber composite nonlinear vibration reduction and isolation device according to an embodiment of the present invention; Figure 3 This is a side view of the magnetic-rubber composite nonlinear vibration reduction and isolation device according to an embodiment of the present invention.

[0022] In the diagram: 1. MEMS gyroscope assembly, 2. carrier plate, 3. base, 4. rubber support, 5. magnet assembly, 6. carrier, 51. upper magnet, 52. lower magnet. Detailed Implementation

[0023] The technical solution of the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention. In this embodiment, the predetermined direction is the vertical direction, the first moving member is a bearing plate, the second moving member is a base, and the damping elastic support member is a rubber support member.

[0024] like Figures 1 to 3As shown, the composite nonlinear vibration damping and isolation device for a MEMS gyroscope in this embodiment is installed between the MEMS gyroscope assembly 1 and the carrier 6 (mounting base), and includes the MEMS gyroscope assembly 1, a support plate 2, a base 3, a rubber support 4, and a magnet assembly 5. The MEMS gyroscope assembly 1 includes the MEMS gyroscope body and a housing, circuit board, or mounting bracket for mounting the gyroscope. The support plate 2 is located below and fixedly connected to the MEMS gyroscope assembly 1; the base 3 is located below the support plate 2 and is approximately parallel to it, and is fixedly connected to the carrier 6. The rubber support 4 is vertically disposed between the support plate 2 and the base 3, with its upper end connected to the support plate 2 and its lower end connected to the base 3, forming a perpetually existing first load-bearing path responsible for static load bearing, small-amplitude vibration isolation, resetting, and energy dissipation. The magnet assembly 5 includes an upper magnet 51 and a lower magnet 52. The magnetization axes of each set of upper magnets 51 and lower magnets 52 are arranged vertically, and their opposite working surfaces are magnetic poles of the same name. The upper magnet 51 is fixed on the side of the bearing plate 2 facing the base 3, and the lower magnet 52 is fixed on the side of the base 3 facing the bearing plate 2, forming a second bearing path with an initial gap, responsible for non-contact progressive stiffening under large displacement impact. The two bearing paths are structurally connected in parallel.

[0025] The support plate 2 is used to fix the MEMS gyroscope assembly 1 and to transfer the gravity, vibration load, and impact inertial load of the gyroscope to the rubber support 4 and the magnet assembly 5. It also connects the upper magnet and the rubber support 4. The support plate 2 should have sufficient bending stiffness so that it approximates rigid body motion during vertical movement, avoiding the influence of its own deformation on the measurement results of the MEMS gyroscope. The base 3 is fixedly connected to the carrier 6 or the mounting foundation and is used to mount the lower magnet and the rubber support 4. External vibrations or impacts on the carrier 6 are first transmitted to the base 3, and then through the rubber support 4 and the magnet assembly 5 to the support plate 2 and the MEMS gyroscope. The base 3 should also have sufficient bending stiffness to avoid the influence of its own deformation on the measurement results of the MEMS gyroscope.

[0026] Rubber support 4 is disposed between the bearing plate 2 and the base 3, bearing all or most of the static load of the MEMS gyroscope and the bearing plate 2. It provides vibration isolation under normal small amplitude conditions, provides elastic recovery force during impact, and suppresses continuous reciprocating oscillation after impact through its own damping and hysteresis loss. In this embodiment, five rubber support 4 are provided, four of which are located in the four corner areas of the bearing plate 2 and one in the central area of ​​the bearing plate 2. In other embodiments, multiple rubber support 4 may also be provided symmetrically distributed about the center of gravity of the MEMS gyroscope component 1 and along the vertical centerline. The rubber support 4 may also be replaced by other viscoelastic support components that have both elastic recovery and damping energy dissipation capabilities, such as silicone damping pads and polyurethane elastomers.

[0027] In the magnet assembly 5, each set of magnets includes an upper magnet 51 fixed to the lower part of the support plate 2 and a lower magnet 52 fixed to the base 3. The upper magnet 51 and the lower magnet 52 are arranged coaxially in the vertical direction, and their opposite working surfaces are magnetic poles of the same name, generating a magnetic repulsion force between them in the vertical direction. In this embodiment, the magnet assembly 5 is set into two sets, which are located on the center line in the width direction of the support plate 2 and are symmetrically arranged with respect to the projection of the center of gravity of the MEMS gyroscope assembly 1 on the support plate 2, so that the resultant force of the restoring force of each set passes through the center of gravity of the MEMS gyroscope assembly 1 as much as possible, thereby reducing the additional overturning moment and attitude disturbance caused by vertical impact.

[0028] The working principle of the present invention will be explained below in conjunction with each working stage.

[0029] 1. Assembly and static load condition MEMS gyroscope assembly 1 is fixed to the support plate 2, and base 3 is fixed to the carrier 6. Rubber support 4 is pre-compressed and establishes static balance under the action of weight.

[0030] To avoid rigid collisions between the upper and lower magnets, the minimum magnetic gap should be greater than the safety gap reserved after considering manufacturing errors, installation errors, and load deviations; for MEMS gyroscope vibration isolation devices using millimeter-level magnets and precision mechanical assembly, the safety gap... The initial gap can be 0.3 mm to 0.8 mm. Simultaneously, an upper limit should be set for the initial gap: if the initial gap is too large, the magnet assembly 5 will not be able to generate sufficient nonlinear magnetic action within the predetermined impact compression stroke; to ensure that the magnet assembly 5 has sufficient intervention capability, the absolute value of the magnetic stiffness in the static equilibrium state is set to be no less than 10% of the total stiffness of the rubber support 4. According to the law of coaxial magnetic dipole repulsion, the gap is... The magnetic repulsion between the upper and lower magnets is The corresponding absolute value of magnetic stiffness is Therefore, the initial spacing should simultaneously satisfy: (1) in, The maximum stroke allowed by the structure, For safety clearance, The total stiffness of rubber support component 4, and These are the magnetic dipole moments of the upper and lower magnet assemblies, respectively. The permeability of free space, This refers to the distance between the upper and lower magnets in a static equilibrium state.

[0031] According to Hooke's Law, the total elastic restoring force generated by the rubber support 4 under static equilibrium is: (2) in, The total stiffness of rubber support component 4, This represents the compression under static load.

[0032] According to the law of repulsion between coaxial magnetic dipoles, the repulsive force generated by magnet assembly 5 in static equilibrium is: (3) in, and These are the magnetic dipole moments of the upper and lower magnet assemblies, respectively. The permeability of free space, This represents the distance between the upper and lower magnets in static equilibrium. At this point, the upper and lower magnets with the same pole maintain the initial gap, the magnetic repulsion is zero or accounts for only a small proportion of the static load, and the static load is mainly borne by the rubber support 4.

[0033] 2. Small amplitude state When the carrier 6 generates normal small-amplitude vibrations, the bearing plate 2 makes small-amplitude movements near the static equilibrium point. When the bearing plate 2 vibrates slightly from its static equilibrium position, the total compression of the rubber support 4 is: (4) in, This is the compression under static load. This represents the displacement of the bearing plate 2 during small-amplitude vibrations.

[0034] When using a linear viscoelastic model, according to Hooke's law, the total force generated by the rubber support 4 is: (5) in, The damping coefficient of rubber support component 4 is... The velocity of the bearing plate 2 during small-amplitude vibration.

[0035] According to the law of repulsion of coaxial magnetic dipoles, the repulsive force of magnet assembly 5 at this time is: (6) The total force between the rubber support 4 and the magnet assembly 5, obtained by linear superposition, is: (7) Compared to the static equilibrium state, the increased restoring force of the rubber support 4 is: (8) Compared to the static equilibrium state, due to the amplitude The increase in restoring force generated by the magnet is relatively small, approximately 0: (9) Therefore, the total restoring force increment relative to the static equilibrium state is: (10) As can be seen from equation (10), when there is a small amplitude vibration, the device behaves as a low stiffness, damped vibration isolation system determined by the rubber support 4, and the magnet assembly 5 is approximately not involved, thereby reducing the transmission of small amplitude vibration to the MEMS gyroscope.

[0036] 3. High-impact compression state When the vertical impact causes the bearing plate 2 to compress rapidly towards the base 3, the rubber support 4 first increases the restoring force and dissipates some energy; as the gap between the upper and lower magnets decreases rapidly, the magnetic repulsion increases non-linearly, resulting in increased non-contact stiffness. When the bearing plate 2 continues to move downwards with a large amplitude from its static equilibrium position, the total compression of the rubber support 4 is: (11) in, This represents the displacement of the bearing plate 2 during large-amplitude vibration.

[0037] When using a linear viscoelastic model, according to Hooke's law, the total force generated by the rubber support 4 is: (12) in, The velocity of the bearing plate 2 during large-amplitude vibration.

[0038] According to the law of repulsion of coaxial magnetic dipoles, the repulsive force of magnet assembly 5 at this time is: (13) The total force between the rubber support 4 and the magnet assembly 5, obtained by linear superposition, is: (14) Compared to the static equilibrium state, the increased restoring force of the rubber support 4 is: (15) The increment of the restoring force generated by the magnet relative to the static equilibrium state is: (16) The total restoring force increment relative to the static equilibrium state, obtained by linear superposition, is: (17) As shown in equations (16) and (17), as the bearing plate 2 moves towards the base 3, the magnetic gap gradually decreases, and the magnetic repulsion force increases rapidly inversely to the fourth power of the gap, thus forming a non-contact, nonlinear, progressive stiffening effect. The magnetic repulsion force and the rubber restoring force together reduce the speed at which the bearing plate 2 continues to move downward and limit the maximum stroke, avoiding contact between the upper and lower magnets and rigid impact between the bearing plate 2 and the base 3. If necessary, a soft rubber limiting block that only contacts the bearing plate 2 near the limit displacement can be set between the bearing plate 2 and the base 3 as a failure protection.

[0039] 4. Unloading and residual vibration attenuation status After the impact peak, the magnetic repulsion and rubber restoring force push the bearing plate 2 back to its static equilibrium position. As the magnetic gap increases, the magnetic repulsion rapidly weakens and ceases to bear the main load, while the hysteresis energy dissipation of the rubber gradually attenuates the residual vibration. If the carrier 6 generates a reverse relative movement that moves the bearing plate 2 away from the base 3, the magnetic repulsion further decreases, and the bearing plate 2 is still constrained and reset by the rubber support 4 connected to the upper and lower mounting components. When the bearing plate 2 vibrates from its static equilibrium position, the amplitude is... At that time, the total compression of the rubber support 4 is: (18) in, This represents the displacement of the bearing plate 2 during unloading and residual vibration attenuation.

[0040] At this moment, the total force between the rubber support 4 and the magnet assembly 5 is: (19) in, The speed of the bearing plate 2 during unloading and residual vibration attenuation.

[0041] The magnet's action is a conservative force; the rubber damper continuously dissipates mechanical energy, and the system's mechanical energy satisfies: (20) in, For the system's mechanical energy, Over time, as the rubber damper continues to dissipate mechanical energy, the structure gradually returns to its equilibrium position.

[0042] The following is an example with specific design parameters. This example is a magnetic-rubber composite nonlinear vibration reduction and isolation device for MEMS gyroscopes. In the model, the equivalent mass of MEMS gyroscope component 1 is 0.12 kg, and its external dimensions are 70 mm × 70 mm × 30 mm.

[0043] Carrier plate 2: made of aluminum alloy, 120 mm in diameter and 10 mm in thickness, with nickel plating on the surface; MEMS gyroscope component 1 is fixed to the upper surface of carrier plate 2 by four screws.

[0044] Base 3: Made of aluminum alloy, 120 mm in diameter and 10 mm in thickness, with nickel plating on the surface, and fixed to the carrier 6 by screws.

[0045] Rubber support component 4: Made of natural rubber with a Shore hardness of A80, cylindrical in shape with a diameter of 7.5 mm; five components are provided, four located at the four corners of the bearing plate 2 and one in the center of the bearing plate 2; the rubber is fixed to the bearing plate 2 and the base 3 by vulcanization bonding; the total rigidity of the five rubber support components 4 is... Damping coefficient .

[0046] Magnet assemblies 5: Two sets are arranged symmetrically from left to right, located on the centerline of the width direction of the support plate 2, 20 mm from the center; in each set of magnet assemblies 5, the upper magnet 51 is fixed to the lower surface of the support plate 2, and the lower magnet 52 is fixed to the upper surface of the base 3. The magnetization axis is perpendicular to the plate surface, and the opposite working surfaces are both The upper magnet 51 and the lower magnet 52, being of the same pole, face each other and generate an axial repulsive force; the working surface area of ​​a single magnet is 3126.63 mm². 2 ,thickness The diameter is 12 mm, and the magnetic dipole moments of both the upper magnet 51 and the lower magnet 52 are 10.928 A·m. 2 .

[0047] Initial clearance design: maximum allowable stroke of the structure The safety clearance is 18 mm. The initial gap is 0.5 mm; according to the lower limit condition of equation (1), the minimum initial gap is 18.5 mm; based on the known total stiffness of the rubber support 4 and the parameters of the magnet assembly 5, the maximum initial gap is 42.33 mm according to the upper limit condition of equation (1). After the device is assembled and reaches static balance, the initial gap between the upper and lower magnet working surfaces is taken. This satisfies the requirements of equation (1). At this point, the maximum allowable impact compression displacement is 18 mm, corresponding to the minimum magnetic gap. The gap is greater than the reserved safety gap of 0.5mm, so the upper and lower magnets will not come into contact.

[0048] Rubber support component height design: To prevent the installation space from being insufficient to meet the minimum magnetic gap requirement due to the insufficient height of the rubber support component 4, the minimum height of the rubber support component 4 should meet the following requirements: (twenty one) in, The thickness of a single magnet. The maximum stroke allowed by the structure, For safety clearance. Substituting the parameters in this embodiment yields... .

[0049] Meanwhile, to prevent the rubber support component 4 from becoming unstable and failing during large-amplitude vibrations, the height of the rubber support component 4 should also meet the maximum height requirement. The peak impact force and the impact load value were obtained through impact simulation. The peak impact force is denoted as: (twenty two) The maximum height of rubber support 4 is: (twenty three) in, This represents the impact load value. The elastic modulus of the rubber support 4 is... The total cross-sectional area of ​​rubber support 4 is... The instability coefficient (in this embodiment, we take...) In this embodiment, the peak impact force was measured by impact simulation. Substituting into equation (23), the maximum height of the rubber support 4 is calculated. Height of rubber support 4 Should meet: (twenty four) That is, the height of the rubber support 4 The value of should simultaneously satisfy the lower limit determined by equation (21) and the upper limit determined by equations (23) and (24). In this embodiment, the distance between the lower surface of the bearing plate 2 and the upper surface of the base 3 is determined by the thickness of the upper magnet 51 and the initial gap. The thickness of the lower magnet 52 is determined by combining the thickness of the two parts, which is 2 × 12 + 20 = 44 mm. The height of the rubber support 4 is... To match this spacing, a value of 44 mm is chosen, which satisfies the requirement. The height of rubber support 4 meets the requirements.

[0050] Impact simulation was performed on the device in this embodiment: approximately 9100 m / s² was input from the bottom of the device. 2 The simulation results show that the maximum acceleration experienced by the gyroscope in the pure rubber vibration isolation scheme is 4722 m / s². 2 The maximum acceleration that the gyroscope can withstand when using the scheme in this embodiment is 3199.8 m / s². 2 This further reduces the transient acceleration by approximately 32.2% compared to the pure rubber solution (and by approximately 16.7% in terms of the transmissibility measured by normalized input acceleration). Therefore, this invention significantly reduces the peak transient acceleration transmitted to the MEMS gyroscope under high-impact conditions while maintaining low-stiffness vibration isolation under normal operating conditions.

[0051] It should be noted that the quantity, material (in addition to natural rubber, viscoelastic materials with both elastic recovery and damping energy dissipation capabilities, such as silicone damping pads and polyurethane elastomers), number and arrangement of magnet components 5, magnet specifications, rubber material and hardness, initial gap, and other parameters of the damping elastic support components (rubber support components 4) in the above embodiments can all be matched and adjusted according to the mass, normal vibration frequency band, and designed impact stroke of the MEMS gyroscope; non-magnetic mounting bases, symmetrical magnetic circuits, or magnetic shielding components can also be used to control the magnetic field influence of the sensor installation area. All equivalent substitutions, simple modifications, or improvements made under the concept of this invention should fall within the protection scope of this invention.

[0052] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A composite nonlinear vibration reduction and isolation device for MEMS gyroscopes, characterized in that, include: The first moving component is used to fix and mount the MEMS gyroscope assembly; The second moving component is disposed opposite to the first moving component and is used to be fixedly connected to the carrier; At least one damping elastic support is disposed between the first moving member and the second moving member in a predetermined direction. The two ends of the damping elastic support are fixedly connected to the first moving member and the second moving member, respectively, forming a first bearing path that always bears the load. A magnet assembly includes an upper magnet fixed to the side of the first moving member facing the second moving member and a lower magnet fixed to the side of the second moving member facing the first moving member. The upper magnet and the lower magnet are arranged coaxially along the predetermined direction. The magnetization axes of the upper magnet and the lower magnet are both along the predetermined direction, and their opposite working surfaces are magnetic poles of the same name, forming a second bearing path. The second bearing path is structurally parallel to the first bearing path. In a static equilibrium state, a predetermined initial gap is maintained between the working surfaces of the upper magnet and the lower magnet.

2. The composite nonlinear vibration reduction and isolation device for MEMS gyroscopes according to claim 1, characterized in that, The damping elastic support is a rubber support, a silicone damping pad, or a polyurethane elastomer support.

3. The composite nonlinear vibration reduction and isolation device for MEMS gyroscopes according to claim 2, characterized in that, The damping elastic support is a cylinder made of natural rubber with a Shore hardness of A80. The damping elastic support is fixedly connected to the first moving component and the second moving component by vulcanization bonding.

4. The composite nonlinear vibration reduction and isolation device for MEMS gyroscopes according to claim 1, characterized in that, The damping elastic support is multiple, and the magnet assembly is one or more sets. The multiple damping elastic support and the multiple sets of magnet assemblies are symmetrically distributed about the centerline passing through the center of gravity of the MEMS gyroscope assembly and along the predetermined direction, so that the resultant force of the restoring force generated by the damping elastic support and the magnet assembly passes through the center of gravity of the MEMS gyroscope assembly.

5. The composite nonlinear vibration reduction and isolation device for MEMS gyroscopes according to claim 1, characterized in that, The initial gap satisfy: in, This represents the maximum allowable impact compressive displacement of the structure. A safety gap is provided to prevent the upper magnet from contacting the lower magnet. The total stiffness of the damping elastic support member , These are the magnetic dipole moments of the upper magnet and the lower magnet, respectively. is the vacuum permeability.

6. The composite nonlinear vibration reduction and isolation device for MEMS gyroscopes according to claim 5, characterized in that, The safety gap Take a diameter of 0.3 mm to 0.8 mm.

7. The composite nonlinear vibration reduction and isolation device for MEMS gyroscopes according to claim 1, characterized in that, There are five damping elastic support members, four of which are located at the four corners of the first moving member and one is located in the central area of ​​the first moving member; there are two sets of magnet assemblies, and the two sets of magnet assemblies are symmetrically arranged with respect to the projection of the center of gravity of the MEMS gyroscope assembly onto the first moving member.

8. The composite nonlinear vibration reduction and isolation device for MEMS gyroscopes according to claim 1, characterized in that, Both the first and second motion components are made of non-magnetic materials; the device further includes a magnetic shield for controlling the magnetic field distribution in the mounting area of ​​the MEMS gyroscope assembly, and / or the magnet assembly adopts a symmetrical magnetic circuit structure.

9. The composite nonlinear vibration reduction and isolation device for MEMS gyroscopes according to any one of claims 1 to 8, characterized in that, It also includes a soft limiting block disposed between the first moving member and the second moving member. The soft limiting block has a gap between itself and its opposite surface, and only contacts the opposite surface when the first moving member reaches its limit displacement, thus forming a failure protection.

10. A composite nonlinear vibration reduction and isolation method for MEMS gyroscopes, characterized in that, The composite nonlinear vibration reduction and isolation device for MEMS gyroscopes as described in any one of claims 1 to 9 includes the following steps: (1) Initial clearance determination steps: Based on the maximum allowable impact compression displacement of the structure With safety clearance Determine the initial gap The lower limit makes According to the total stiffness of the damping elastic support member and the magnetic dipole moments of the upper magnet and the lower magnet , Determine the initial gap The upper limit is such that the absolute value of the magnetic stiffness of the magnet assembly in static equilibrium is not less than 10% of the total stiffness of the damping elastic support; (2) Assembly and static load steps: Fix the MEMS gyroscope assembly to the first motion component, fix the second motion component to the carrier, the damping elastic support is pre-compressed and establishes static balance under static load, the upper magnet and the lower magnet maintain a predetermined initial gap, and all or most of the static load is borne by the damping elastic support. (3) Small amplitude vibration isolation step: When the carrier generates normal small amplitude vibration, the first moving component makes small amplitude movement near the static equilibrium position, and the damping elastic support provides low stiffness and damped vibration isolation. The magnetic repulsion force increment generated by the magnet assembly is approximately zero. (4) Large impact limiting step: When the impact compresses the first moving component toward the second moving component, the damping elastic support first increases the restoring force and dissipates part of the energy; As the magnetic gap decreases, the magnetic repulsion between the upper magnet and the lower magnet increases nonlinearly inversely proportional to the fourth power of the magnetic gap. Together with the restoring force of the damping elastic support, this limits the maximum stroke of the first moving member, preventing the upper magnet from contacting the lower magnet and the first moving member from rigidly colliding with the second moving member. (5) Unloading and residual vibration attenuation steps: After the impact peak, the magnetic repulsion force and elastic restoring force push the first moving component back to the static equilibrium position. The magnetic repulsion force weakens rapidly as the magnetic gap increases and exits the load. The residual vibration is attenuated by the hysteresis energy dissipation of the damping elastic support, and the first moving component returns to the static equilibrium position.

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