Vibration Measurement and Control Device and Method for Multi-Layer Quasi-Zero Stiffness Damping Structures

Abstract

This invention discloses a vibration measurement and control device for a multi-layer quasi-zero stiffness damping structure, comprising a first quasi-zero stiffness platform section, a second quasi-zero stiffness platform section, a vibration detection section, and a vibration excitation section. The first and second quasi-zero stiffness platform sections are each equipped with a flexural electric displacement sensor possessing quasi-zero stiffness characteristics. The first quasi-zero stiffness platform section includes a first quasi-zero stiffness platform, a linkage platform, a linkage mechanism, a cam mechanism, and a first spring-magnetic damping element. The second quasi-zero stiffness platform section includes a second quasi-zero stiffness platform, a second spring-magnetic damping element, an air hydrostatic guide rail, a top platform, and a vibration platform. The exciter induces vibration in the damping structure, and the vibration signal of the damping structure can be measured using the flexural electric displacement sensor. This device can be used to study the vibration isolation effect of multi-layer quasi-zero stiffness damping structures under low-frequency disturbances, and has certain application prospects in the design and vibration measurement of multi-layer quasi-zero stiffness damping structures.

Description

Technical Field

[0001] This invention relates to the field of vibration detection of quasi-zero stiffness structures, and more specifically, to a vibration measurement and control device and method for multi-layer quasi-zero stiffness damping structures. Background Technology

[0002] During an earthquake, the vibration of the main building structure can cause collapse and disintegration, resulting in irreparable loss of life and property. Modern structural design typically emphasizes earthquake resistance, vibration damping, and shock absorption to ensure that the main structure protects the site from vibration disturbances in various situations. Generally, structural design focuses on a rational layout to distribute energy to various shock-absorbing parts of the structure when the facade suddenly changes, thus diluting the vibration. Magnitude is an indicator used to measure the amount of energy released by an earthquake, while intensity indicates the degree of damage to building structures and topography. Generally, earthquakes of magnitude 4 or higher will cause some degree of damage to building structures on the ground. From intensity 4 onwards, buildings shake significantly, severely damaging the structure and causing irreparable losses. Therefore, designing a low-frequency vibration isolation system and conducting vibration monitoring is necessary.

[0003] In recent years, the design of quasi-zero stiffness vibration isolation platforms has become a key and hot research topic in my country. For large structures like vibration isolation platforms, multiple and multi-layer quasi-zero stiffness structures are generally used to achieve vibration isolation of large systems. Among them, various magnetic damping and spring damping are used to achieve negative stiffness, and air static pressure guide rail platforms are used to achieve low-frequency vibration isolation of the entire platform. This enables the structure to respond more quickly and accurately under low-frequency vibration and absorb vibration energy. Summary of the Invention

[0004] The purpose of this invention is to overcome the shortcomings and deficiencies of existing technologies in the design and vibration detection of quasi-zero stiffness vibration isolation platforms, and to provide a vibration measurement and control device and method for multi-layer quasi-zero stiffness damping structures. By utilizing the quasi-zero stiffness characteristics of flexural electric displacement sensors and their influence on additional electric field electrodes, vibration detection of quasi-zero stiffness damping structures can be achieved.

[0005] To achieve the above objectives, the technical solution adopted by the present invention is as follows:

[0006] A vibration monitoring and control device for a multi-layer quasi-zero stiffness damping structure includes a first quasi-zero stiffness platform section, a second quasi-zero stiffness platform section, a vibration detection section, and a vibration excitation section;

[0007] The first quasi-zero stiffness platform section includes a first quasi-zero stiffness platform, a linkage platform, a linkage mechanism, a cam mechanism, and a first spring-magnetic damping component; the second quasi-zero stiffness platform section includes a second quasi-zero stiffness platform, a second spring-magnetic damping component, an air hydrostatic guide rail, a top platform, and a vibration platform;

[0008] The linkage mechanism is connected to the first quasi-zero stiffness platform, the linkage platform is connected to the linkage mechanism, the cam mechanism is connected to the linkage mechanism, the second quasi-zero stiffness platform is connected to the linkage mechanism through the cam mechanism, one end of the first spring-magnetic damping element is connected to the linkage platform, the other end of the first spring-magnetic damping element is connected to the second quasi-zero stiffness platform, and the second quasi-zero stiffness platform and the linkage platform are coupled through spring and magnetic damping;

[0009] One end of the second spring-magnetic damping component is connected to the second quasi-zero stiffness platform, and the other end of the second spring-magnetic damping component is connected to the top platform. One end of the air static pressure guide rail is connected to the second quasi-zero stiffness platform, and the other end of the air static pressure guide rail is connected to the top platform. The vibration platform is connected above the top platform. The second quasi-zero stiffness platform and the top platform are coupled through springs and magnetic damping.

[0010] The vibration detection section includes a multi-degree-of-freedom flexural electric displacement sensor and a single-degree-of-freedom flexural electric displacement sensor. The multi-degree-of-freedom flexural electric displacement sensor is fixed to the first quasi-zero stiffness platform, and the connecting rod platform is connected to the multi-degree-of-freedom flexural electric displacement sensor. The single-degree-of-freedom flexural electric displacement sensor is fixed to the top platform, and the vibration platform is connected to the single-degree-of-freedom flexural electric displacement sensor.

[0011] The vibration excitation part includes a vibrator and a third spring-magnetic damping component. The third spring-magnetic damping component includes a support guide rod, a support spring, and a linear bearing. One end of the support guide rod is fixed to the experimental platform, and the other end of the support guide rod passes through the linear bearing and is fixed to the first quasi-zero stiffness platform. The support spring is located between the support guide rod and the linear bearing. The vibrator is fixed to the experimental platform and located below the first quasi-zero stiffness platform. The vibrator is connected to the first quasi-zero stiffness platform through a top rod.

[0012] Preferably, the linkage mechanism includes a first link, a second link, and a link spring. The first link is connected to a first quasi-zero stiffness platform and a cam, the second link is connected to the link platform and the first link, and the link spring is connected to the cam mechanism and the link platform.

[0013] Preferably, the cam mechanism includes a cam support, a cam, and a roller. One end of the cam support is connected to the first connecting rod, and the other end of the cam support is connected to the roller. The cam is fixed below the second quasi-zero stiffness platform, and the roller is in contact with the cam.

[0014] Preferably, the multi-degree-of-freedom flexural electric displacement sensor is fixed at the center of the first quasi-zero stiffness platform, and the multi-degree-of-freedom flexural electric displacement sensor is connected to the linkage platform through the third link and the inverted "T"-shaped seat.

[0015] Preferably, four first spring-magnetic damping elements are fixed on the connecting rod platform. Each first spring-magnetic damping element includes two supports, which are respectively fixed to the connecting rod platform and the second quasi-zero stiffness platform, and magnets are fixed on the supports.

[0016] Preferably, the second quasi-zero stiffness platform and the top platform are connected by four second spring-magnetic damping elements and four air static pressure guide rails. The four second spring-magnetic damping elements are respectively connected to the four corners of the top platform, and the four air static pressure guide rails are respectively connected to the four sides of the top platform.

[0017] Preferably, the second quasi-zero stiffness platform further includes a magnetic damping slider and a magnetic damping "concave" seat. The magnetic damping slider is fixed on the slider of the air static pressure guide rail, and the magnetic damping "concave" seat is fixed on the second quasi-zero stiffness platform and located in front of the air static pressure guide rail. The hollow part in the middle of the magnetic damping "concave" seat corresponds to the magnet of the slider of the air static pressure guide rail.

[0018] Preferably, the second spring magnet damping component includes two supports, which are respectively fixed to the second quasi-zero stiffness platform and the top platform. Magnets are fixed on the supports, and the magnets form magnetic coupling with the magnets of the slider of the air hydrostatic guide rail.

[0019] Preferably, the multi-degree-of-freedom flexural displacement sensor and the single-degree-of-freedom flexural displacement sensor are manufactured by 3D printing or made of polyvinylidene fluoride. The 3D printing material is UV-cured plastic VisiJet M3 Crystal. Positive and negative electrodes are attached to the multi-degree-of-freedom flexural displacement sensor and the single-degree-of-freedom flexural displacement sensor at intervals.

[0020] A method for vibration monitoring and control of a multi-layer quasi-zero stiffness damping structure, applied to the vibration monitoring and control device for the multi-layer quasi-zero stiffness damping structure described above, includes the following steps:

[0021] S1: Use a computer-controlled vibrator to perform vibration excitation in order to achieve the desired low-frequency vibration and excite the multi-layer quasi-zero stiffness damping structure to generate low-frequency vibration signals.

[0022] S2: Vibration signals of the first quasi-zero stiffness platform, the connecting rod platform, the top platform, and the vibration platform are obtained using a multi-degree-of-freedom flexural electric displacement sensor and a single-degree-of-freedom flexural electric displacement sensor.

[0023] S3: The obtained vibration signal is processed by the charge amplifier and then transmitted to the motion control card through the terminal board. The motion control card converts the analog signal into a digital signal and then transmits it to the computer.

[0024] S4: By analyzing and processing the received vibration signals, the computer obtains the corresponding vibration feedback signals and acquires the performance of the multi-layer quasi-zero stiffness damping structure under low-frequency vibration.

[0025] Compared with the prior art, the present invention has the following advantages and beneficial effects:

[0026] 1. This invention studies a vibration isolation method with a multi-layer quasi-zero stiffness structure. The multi-layer quasi-zero stiffness structure includes magnetic damping, cam mechanism, linkage mechanism, and air hydrostatic guide rail. Compared with other research devices, it can better study the vibration isolation effect of various quasi-zero stiffness devices.

[0027] 2. This invention uses a flexural electric displacement sensor to realize vibration measurement of a multi-layer quasi-zero stiffness structure. Compared with other sensors, the flexural electric displacement sensor has quasi-zero stiffness characteristics, which can reduce additional stiffness and isolate vibration while providing high-precision measurement. At the same time, it can effectively enhance sensitivity and reduce noise in signal transmission.

[0028] 3. Through reasonable mechanical design, this invention applies spring damping and magnetic damping to each layer of quasi-zero stiffness structure, and ensures the vibration characteristics of the multi-layer quasi-zero stiffness device through the preload stroke of the air hydrostatic guide rail.

[0029] 4. This invention uses a multi-degree-of-freedom flexural electric displacement sensor to detect the vibration displacement of the first-layer quasi-zero stiffness structure. Compared with a single-degree-of-freedom flexural electric displacement sensor, it has the characteristics of multi-degree-of-freedom measurement, convenient installation, and good linearity, and can more comprehensively detect the vibration displacement of the first-layer quasi-zero stiffness structure.

[0030] 5. This invention employs multi-sensor measurement, including both multi-degree-of-freedom flexural electrical displacement sensors and multiple single-degree-of-freedom flexural electrical displacement sensors, which helps to improve the breadth and accuracy of the measurement. Attached Figure Description

[0031] Figure 1 This is a schematic diagram of a vibration monitoring and control device for a multi-layer quasi-zero stiffness damping structure.

[0032] Figure 2 This is the front view of a vibration monitoring and control device for a multi-layer quasi-zero stiffness damping structure.

[0033] Figure 3 This is a schematic diagram of the structure of a multi-degree-of-freedom flexural electric displacement sensor.

[0034] Figure 4 This is a schematic diagram of a single-degree-of-freedom flexural electric displacement sensor.

[0035] Figure 5 This is a schematic diagram of the structure of an air static pressure guide rail.

[0036] Figure 6 This is a schematic diagram of the vibrator.

[0037] Figure 7 This is a flowchart of the vibration control process for a vibration monitoring and control device for a multi-layer quasi-zero stiffness damping structure.

[0038] Explanation of icon numbers:

[0039] 1-Experimental platform; 2-Supporting guide rod; 3-Supporting spring; 4-Linear bearing; 5-First connecting rod; 6-Second connecting rod; 7-Connecting rod spring; 8-Cam support; 9-Roller; 10-Cam; 11-Damping spring; 12-Support; 13-Second quasi-zero stiffness platform; 14-Long spring; 15-Long spring support rod; 16-Bottom support plate; 17-Magnetic damping "concave" shaped seat; 18-"T" shaped bracket;

[0040] 19-Magnetic damping slider; 20-Air static pressure guide rail; 21-Top platform; 22-Single-degree-of-freedom flexural electric displacement sensor; 23-Vibration platform; 24-Linkage platform; 25-Inverted "T" shaped seat; 26-Third link; 27-Multi-degree-of-freedom flexural electric displacement sensor; 28-First quasi-zero stiffness platform; 29-Vibrator; 30-Vibrator base. Detailed Implementation

[0041] The vibration measurement and control device and method for multi-layer quasi-zero stiffness damping structures of the present invention will be further described below with reference to the accompanying drawings and specific embodiments.

[0042] Please see Figure 1 This invention discloses a vibration monitoring and control device for a multi-layer quasi-zero stiffness damping structure. The device includes a first quasi-zero stiffness platform, a second quasi-zero stiffness platform, a vibration detection section, and a vibration excitation section. This invention constructs a multi-layer quasi-zero stiffness damping structure with spring coupling, magnetic coupling, an air hydrostatic guide rail platform, and a flexural electric displacement sensor. Utilizing the quasi-zero stiffness characteristics of the flexural electric displacement sensor and its influence on the additional electric field electrodes, vibration detection of the quasi-zero stiffness damping structure can be achieved.

[0043] Please see Figure 1 and Figure 2 The first quasi-zero stiffness platform includes a cam mechanism and a linkage mechanism, wherein the linkage mechanism is connected to the linkage platform 24, and the linkage platform 24 is connected to the second quasi-zero stiffness platform 13 through a spring-magnet damping mechanism. A multi-degree-of-freedom flexural electric displacement sensor 27 is connected below the linkage platform 24.

[0044] The linkage mechanism includes four first links 5 and four second links 6. One end of each of the four first links 5 is fixed to the first quasi-zero stiffness platform 28, enabling it to rotate. One end of each of the four second links 6 is connected to the first links 5 near the linkage platform 24, and the other end is connected to the four sides of the linkage platform 24. Linkage springs 7 are connected to the four sides of the linkage platform 24 connected to the second links 6 by screws. The other end of the linkage springs 7 is connected to the cam support 8 by hooks. The center of the cam support 8 is fixed to the other end of the first link 5. The other end of the cam support 8 is fixed to the roller 9 by bolts. The roller 9 is connected to the cam 10 through contact. The cam 10 is fixed to the cam suspension device on the second quasi-zero stiffness platform 13 by bolts.

[0045] Four first spring-magnetic damping elements are fixed to the connecting rod platform 24. Four supports 12 are fixed in the connecting rod platform 24 by bolts. Magnets are fixed on the supports 12 and connected to the second quasi-zero stiffness platform 13 by damping springs 11. Supports 12 are also fixed at the connection of the second quasi-zero stiffness platform 13, so that the second quasi-zero stiffness platform 13 can reciprocate smoothly relative to the connecting rod platform 24 under vibration excitation.

[0046] Four second spring magnetic damping components are bolted to the four sides of the second quasi-zero stiffness platform 13. Each second spring magnetic damping component includes a long spring 14, a long spring support rod 15, and a support 12. Four air static pressure guide rails 20 are bolted to the four sides of the second quasi-zero stiffness platform 13. A magnetic damping concave seat 17 is placed in front of each air static pressure guide rail 20 device.

[0047] Please see Figure 1 and Figure 5 Each air static pressure guide rail 20 has a magnetic damping slider 19, which is fixed with a "T"-shaped bracket 18 by screws. The center of the "T"-shaped bracket 18 is placed with a magnet, and the top is connected to one side of the top platform 21. Before vibration occurs, the magnetic damping slider 19 on each air static pressure guide rail 20 needs to be preset to a suitable position close to the center to ensure that during vibration, the magnetic damping slider 19 will not drive the "T"-shaped bracket 18 to touch the magnetic damping "concave" seat 17.

[0048] Magnets are placed on the protruding parts on both sides of the magnetic damping concave seat 17 so that they can form magnetic coupling with the magnet in the "T"-shaped bracket 18 that is fixed to the magnetic damping slider 19 on the air static pressure guide rail 20.

[0049] Please see Figure 1 and Figure 6The vibration excitation part includes a support guide rod 2, a support spring 3, a linear bearing 4, and a vibrator 29. The vibrator 29 is fastened to the experimental table 1 by a vibrator base 30 and screws. The top of the vibrator 29 touches the first quasi-zero stiffness platform 28 through an extended push rod. When the vibrator 29 is working, the vibrator 29 will drive the push rod to apply a vibration force to the first quasi-zero stiffness platform 28, and the first quasi-zero stiffness platform 28 will generate vibration displacement under the action of the force.

[0050] The first quasi-zero stiffness platform 28, under the action of the support guide rod 2, the support spring 3, and the linear bearing 4, can remain stationary on the experimental table 1 without being subjected to any force. When subjected to a force, the first quasi-zero stiffness platform 28 vibrates, and the multi-layer quasi-zero stiffness damping structure performs small-amplitude reciprocating motion. The vibration excitation of the multi-layer quasi-zero stiffness damping structure is achieved through the exciter 29, which facilitates the vibration detection of the multi-layer quasi-zero stiffness damping structure.

[0051] Please see Figure 3 and Figure 4 The vibration detection section includes a multi-degree-of-freedom flexure electrical displacement sensor 27 and a single-degree-of-freedom flexure electrical displacement sensor 22. The single-degree-of-freedom flexure electrical displacement sensor 22 is located on the top platform 21 and is used to detect the vibration signal of the vibration platform 23, verifying the quasi-zero stiffness characteristics of the vibration platform 23 within a specific range. When vibration occurs, the vibration is transmitted from bottom to top until it reaches the single-degree-of-freedom flexure electrical displacement sensor 22. The single-degree-of-freedom flexure electrical displacement sensor 22 converts the strain into an electrical signal, which is transmitted to the terminal board through a charge amplifier and then processed by the motion control card before being displayed on the computer.

[0052] The multi-degree-of-freedom flexural electric displacement sensor 27 is located on the first quasi-zero stiffness platform 28. Its top has four separate connecting devices, which are respectively connected to the third link 26. The other end of the third link 26 is connected to the inverted "T" shaped seat 25. The inverted "T" shaped seat 25 is connected to the link platform 24 by bolts. When vibration occurs, the link platform 24 transmits the vibration to the inverted "T" shaped seat 25, and then transmits the vibration to the multi-degree-of-freedom flexural electric displacement sensor 27 through the third link 26. The multi-degree-of-freedom flexural electric displacement sensor 27 converts the strain into an electrical signal, which is transmitted to the terminal board through the charge amplifier. After being processed by the motion control card, it is displayed on the computer.

[0053] Both the multi-degree-of-freedom flexural electric displacement sensor 27 and the single-degree-of-freedom flexural electric displacement sensor 22 are made of VisiJet M3 Crystal, a UV-curable plastic commonly used in 3D printing. Positive and negative electrodes are attached alternately to the front and back surfaces of their flexible structures. They are located at the center of the first quasi-zero stiffness platform 28. The four top mechanisms are connected to the four flexible joints respectively. When subjected to compression and bending, the deformation in each direction is independent. Therefore, the direction and magnitude of the deformation at this moment can be calculated by the computer through the electrical signals of the four flexible joints.

[0054] In this embodiment, the experimental table 1 is assembled from two aluminum profiles with lengths of 860mm and 200mm respectively. The table surface is a 980mm×980mm stainless steel plate, which is connected to the profiles by screws. Each connection of the profiles is fixed with angle iron.

[0055] Linear bearing 4 uses JAE linear bearing LM25UU with LM25M steel cage, 6 ball rows, weighs 220g, has an inner diameter of 25mm, an outer diameter of 40mm, a length of 59mm, and a specified rated load of 100kg.

[0056] The air static pressure guide rail 20 uses the EZ-2542 linear air bearing guide rail from ETIZENBERGER, with a stroke of 150mm, a vertical load of 200N, a vertical stiffness of 45N / μm, and a total weight of 7kg. The magnetic damping slider 19 weighs 2kg.

[0057] Four single-degree-of-freedom flexural electric displacement sensors 22 are located at the centers of the four sides of the top platform 21, and a vibration platform 23 is fixed on them. The vibration platform 23 is made of steel plate with dimensions of 600×600mm, the same size as the top platform 21.

[0058] The multi-degree-of-freedom flexural electric displacement sensor 27 has a base width of 245mm and an overall height of 70mm. The single-degree-of-freedom flexural electric displacement sensor 22 has a base width of 324mm, a top width of 120mm, and an overall height of 132mm.

[0059] The vibrator 29 is the Modal Exciter Type 4826 from HBK Bruel & Kjaer, with a main resonant frequency of 4000Hz, an effective frequency range of 2-5000Hz, an operating frequency range of DC-5000Hz, and a maximum rated stroke of 25.4mm.

[0060] In summary, the present invention has the following advantages and beneficial effects:

[0061] 1. This invention studies a vibration isolation method with a multi-layer quasi-zero stiffness structure. The multi-layer quasi-zero stiffness structure includes magnetic damping, cam mechanism, linkage mechanism, and air hydrostatic guide rail. Compared with other research devices, it can better study the vibration isolation effect of various quasi-zero stiffness devices.

[0062] 2. This invention uses a flexural electric displacement sensor to realize vibration measurement of a multi-layer quasi-zero stiffness structure. Compared with other sensors, the flexural electric displacement sensor has quasi-zero stiffness characteristics, which can reduce additional stiffness and isolate vibration while providing high-precision measurement. At the same time, it can effectively enhance sensitivity and reduce noise in signal transmission.

[0063] 3. Through reasonable mechanical design, this invention applies spring damping and magnetic damping to each layer of quasi-zero stiffness structure, and ensures the vibration characteristics of the multi-layer quasi-zero stiffness device through the preload stroke of the air hydrostatic guide rail.

[0064] 4. This invention uses a multi-degree-of-freedom flexural electric displacement sensor to detect the vibration displacement of the first-layer quasi-zero stiffness structure. Compared with a single-degree-of-freedom flexural electric displacement sensor, it has the characteristics of multi-degree-of-freedom measurement, convenient installation, and good linearity, and can more comprehensively detect the vibration displacement of the first-layer quasi-zero stiffness structure.

[0065] 5. This invention employs multi-sensor measurement, including both multi-degree-of-freedom flexural electrical displacement sensors and multiple single-degree-of-freedom flexural electrical displacement sensors, which helps to improve the breadth and accuracy of the measurement.

[0066] The above description is a detailed description of the preferred embodiments of the present invention. However, the embodiments are not intended to limit the scope of the patent application of the present invention. All equivalent changes or modifications made under the technical spirit disclosed in the present invention should fall within the patent scope covered by the present invention.

Claims

1. A vibration monitoring and control device for a multi-layer quasi-zero stiffness damping structure, characterized in that, It includes a first quasi-zero stiffness platform section, a second quasi-zero stiffness platform section, a vibration detection section, and a vibration excitation section; The first quasi-zero stiffness platform includes a first quasi-zero stiffness platform, a linkage platform, a linkage mechanism, a cam mechanism, and a first spring-magnetic damping component; The second quasi-zero stiffness platform section includes a second quasi-zero stiffness platform, a second spring-magnet damping component, an air hydrostatic guide rail, a top platform, and a vibration platform; The linkage mechanism is connected to the first quasi-zero stiffness platform, the linkage platform is connected to the linkage mechanism, the cam mechanism is connected to the linkage mechanism, the second quasi-zero stiffness platform is connected to the linkage mechanism through the cam mechanism, one end of the first spring-magnetic damping element is connected to the linkage platform, the other end of the first spring-magnetic damping element is connected to the second quasi-zero stiffness platform, and the second quasi-zero stiffness platform and the linkage platform are coupled through spring and magnetic damping; One end of the second spring-magnetic damping component is connected to the second quasi-zero stiffness platform, and the other end of the second spring-magnetic damping component is connected to the top platform. One end of the air static pressure guide rail is connected to the second quasi-zero stiffness platform, and the other end of the air static pressure guide rail is connected to the top platform. The vibration platform is connected above the top platform. The second quasi-zero stiffness platform and the top platform are coupled through springs and magnetic damping. The vibration detection section includes a multi-degree-of-freedom flexural electric displacement sensor and a single-degree-of-freedom flexural electric displacement sensor. The multi-degree-of-freedom flexural electric displacement sensor is fixed to the first quasi-zero stiffness platform, and the connecting rod platform is connected to the multi-degree-of-freedom flexural electric displacement sensor. The single-degree-of-freedom flexural electric displacement sensor is fixed to the top platform, and the vibration platform is connected to the single-degree-of-freedom flexural electric displacement sensor. The vibration excitation part includes a vibrator, a support guide rod, a support spring, and a linear bearing. One end of the support guide rod is fixed to the experimental table, and the other end of the support guide rod passes through the linear bearing and is fixed to the first quasi-zero stiffness platform. The support spring is located between the support guide rod and the linear bearing. The vibrator is fixed to the experimental table and located below the first quasi-zero stiffness platform. The vibrator is connected to the first quasi-zero stiffness platform through a top rod. The linkage mechanism includes a first link, a second link, and a link spring. The first link is connected to a first quasi-zero stiffness platform and a cam mechanism, the second link is connected to the link platform and the first link, and the link spring is connected to the cam mechanism and the link platform.

2. The vibration monitoring and control device for a multi-layer quasi-zero stiffness damping structure according to claim 1, characterized in that, The cam mechanism includes a cam support, a cam, and a roller. One end of the cam support is connected to the first connecting rod, and the other end of the cam support is connected to the roller. The cam is fixed below the second quasi-zero stiffness platform, and the roller is in contact with the cam.

3. The vibration monitoring and control device for a multi-layer quasi-zero stiffness damping structure according to claim 1, characterized in that, The multi-degree-of-freedom flexural electric displacement sensor is fixed at the center of the first quasi-zero stiffness platform. The multi-degree-of-freedom flexural electric displacement sensor is connected to the linkage platform through the third link and the inverted "T"-shaped seat.

4. The vibration monitoring and control device for a multi-layer quasi-zero stiffness damping structure according to claim 1, characterized in that, Four first spring-magnetic damping components are fixed on the connecting rod platform. Each first spring-magnetic damping component includes two supports, which are respectively fixed to the connecting rod platform and the second quasi-zero stiffness platform. Magnets are fixed on the supports.

5. The vibration monitoring and control device for a multi-layer quasi-zero stiffness damping structure according to claim 1, characterized in that, The second quasi-zero stiffness platform and the top platform are connected by four second spring magnet damping components and four air static pressure guide rails. The four second spring magnet damping components are respectively connected to the four corners of the top platform, and the four air static pressure guide rails are respectively connected to the four sides of the top platform.

6. The vibration monitoring and control device for a multi-layer quasi-zero stiffness damping structure according to claim 5, characterized in that, The second quasi-zero stiffness platform also includes a magnetic damping slider and a magnetic damping "concave" seat. The magnetic damping slider is fixed on the slider of the air static pressure guide rail, and the magnetic damping "concave" seat is fixed on the second quasi-zero stiffness platform and located in front of the air static pressure guide rail. The hollow part in the middle of the magnetic damping "concave" seat corresponds to the magnet of the slider of the air static pressure guide rail.

7. The vibration monitoring and control device for a multi-layer quasi-zero stiffness damping structure according to claim 5, characterized in that, The second spring magnet damping component includes two supports, which are respectively fixed to the second quasi-zero stiffness platform and the top platform. Magnets are fixed on the supports, and the magnets form magnetic coupling with the magnets of the slider of the air hydrostatic guide rail.

8. The vibration monitoring and control device for a multi-layer quasi-zero stiffness damping structure according to claim 1, characterized in that, The multi-degree-of-freedom flexural displacement sensor and the single-degree-of-freedom flexural displacement sensor are manufactured by 3D printing or made of polyvinylidene fluoride. The 3D printing material is UV-cured plastic VisiJet M3 Crystal. The multi-degree-of-freedom flexural displacement sensor and the single-degree-of-freedom flexural displacement sensor have positive and reverse electrodes attached at intervals.

9. A method for vibration monitoring and control of a multi-layer quasi-zero stiffness damping structure, applied to the vibration monitoring and control device for a multi-layer quasi-zero stiffness damping structure as described in any one of claims 1 to 8, characterized in that, Includes the following steps: S1: Use a computer-controlled vibrator to perform vibration excitation in order to achieve the desired low-frequency vibration and excite the multi-layer quasi-zero stiffness damping structure to generate low-frequency vibration signals. S2: Vibration signals of the first quasi-zero stiffness platform, the connecting rod platform, the top platform, and the vibration platform are obtained using a multi-degree-of-freedom flexural electric displacement sensor and a single-degree-of-freedom flexural electric displacement sensor. S3: The obtained vibration signal is processed by the charge amplifier and then transmitted to the motion control card through the terminal board. The motion control card converts the analog signal into a digital signal and then transmits it to the computer. S4: By analyzing and processing the received vibration signals, the computer obtains the corresponding vibration feedback signals and acquires the performance of the multi-layer quasi-zero stiffness damping structure under low-frequency vibration.

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