Large-scale precision microseismic vibration-oriented negative stiffness damping integrated control device

Abstract

The large-scale precision micro-vibration isolation negative stiffness damping integrated control device belongs to the technical field of precision vibration isolation, adopts a multi-layer axial array arrangement and a vertical magnetization equal-section magnetic ring array to construct a single-side high magnetic density excitation magnetic field, and coaxially nests the vertical magnetization permanent magnet ring array and the moving magnet ring array to realize high negative stiffness characteristics and coaxially nests the coil to realize eddy current damping characteristics; under the action of the acceleration and speed composite feedback control method, adjustable high negative stiffness and low frequency high damping and high frequency low damping characteristics are generated, so that the stiffness and damping parameters of the large-scale precision micro-vibration isolation are accurately matched to realize near full-band high-performance vibration isolation, the vibration isolation performance is maximized, the stability of the vibration isolation system is improved, and the performance bottleneck of single parameter control is effectively avoided.

Description

Technical Field

[0001] This invention belongs to the field of precision vibration isolation technology, and in particular to an integrated control device for negative stiffness damping for large-scale precision micro-vibration isolation. Background Technology

[0002] In the assembly, testing, and experimentation of precision instruments and equipment, low-frequency micro-amplitude vibration interference in the environment has become a key issue affecting research results. Equipping precision instruments and equipment with low-frequency vibration isolators has gradually become a major technical means in the field of precision engineering to suppress environmental micro-vibrations. Stiffness and damping are core parameters determining the isolation bandwidth and isolation effect, directly affecting the effect of the micro-vibration isolation platform on vibrations of different frequencies. Effective control of these parameters is crucial for improving vibration isolation performance. However, existing research mainly focuses on small optical micro-vibration isolation platforms and devices, whose mass is typically within kilograms to hundreds of kilograms, rarely exceeding tons. When addressing the stiffness and damping control requirements of large precision micro-vibration isolation platforms weighing hundreds of tons or more, generating sufficiently high negative stiffness and damping is extremely difficult. Furthermore, current research mostly focuses on controlling a single parameter, stiffness or damping, making it difficult to achieve a synergistic and integrated control effect of stiffness and damping. This limitation makes it difficult for control strategies to achieve optimal performance in complex vibration environments, failing to fully meet the high requirements of large precision instrument systems for micro-vibration isolation.

[0003] Patent CN201810625715.4 (Chongqing University, "Magnetorheological damper with controllable damping and negative stiffness") discloses a device for controllable damping and negative stiffness, consisting of a magnetorheological fluid, a rotating piston disposed within a cylinder assembly, and a ball screw pair cooperating with the rotating piston. By controlling the current in the excitation coil to change the shear yield force of the magnetorheological fluid, controllable damping force is achieved, while controllable negative stiffness of the damper is realized using rotational inertia, thus improving vibration isolation performance. Patent CN201911144675.2 (PLA Unit 92578, "A multifunctional composite vibration isolator") discloses a multifunctional composite vibration isolator composed of an electromagnetic vibration isolator and a magnetorheological damper connected in parallel. The electromagnetic vibration isolator and the magnetorheological damper are each independently supplied with a specific current according to a control algorithm. The electromagnetic vibration isolator uses a magnetic tooth structure, and the electromagnetic stiffness can be adjusted online by changing the excitation current, thereby reducing the natural frequency of vibration isolation. The variable damping technology uses magnetorheological dampers, which also achieve variable damping characteristics by changing the input current. Patent number CN202311509326.2 (Chongqing University, Magnetorheological Multidirectional Broadband Vibration Absorber) combines the advantages of magnetorheological dampers and granular dampers. Six magnetorheological dampers are arranged in a Stewart platform configuration between the upper and lower platforms to provide stiffness and damping in multiple directions, broadening the vibration reduction frequency band of traditional tuned mass dampers and effectively solving the problems of traditional granular dampers.

[0004] The above-mentioned magnetorheological dampers have the following problems when applied to the field of large-scale precision micro-vibration isolation: 1) The shear yield strength of the magnetorheological dampers is low, making it difficult to generate sufficient damping to control large-scale precision micro-vibration isolation of hundreds of tons or more; increasing the damping value by increasing the excitation voltage will increase energy consumption and cost; 2) The properties of magnetorheological fluids are unstable and easily affected by external environmental factors such as temperature and humidity. Under high or low temperature environments, their damping performance may change, and they may even fail to work properly; 3) Long-term use or improper use may cause slag to be generated inside the magnetorheological damper, affecting the damping effect and service life.

[0005] Patent CN201721249979.1 (Tongji University, "An Electromagnetic Damping Negative Stiffness Support") discloses an electromagnetically damped negative stiffness support. This support utilizes the electromagnetic force generated by the relative motion of two coaxially magnetized magnetic rings in the same direction to achieve negative stiffness characteristics, and utilizes the eddy currents generated by the magnetic rings cutting magnetic field lines when they move relative to the conductor plate to provide damping. The features of this technical solution are: 1) The negative stiffness and damping characteristics are achieved through a split structure, which is relatively complex, increasing material and manufacturing costs, and making installation and maintenance difficult; 2) Both the negative stiffness structure and the damping structure are composed of magnetic rings magnetized in a single direction, and the excitation magnetic fields on the inner and outer sides of such magnetic rings are symmetrical. However, in practical applications, only one side of the magnetic field is utilized while the other side is idle, resulting in low magnetic field utilization of the electromagnetic damping negative stiffness support, and low negative stiffness and damping values. This has little effect on controlling the stiffness and damping of large precision micro-vibration isolation platforms of hundreds of tons or more; 3) After the structural design is completed, the negative stiffness and damping values ​​that can be generated are constant and cannot be adaptively adjusted with changes in load mass, excitation frequency and vibration isolation requirements.

[0006] Professor Cui Junning of Harbin Institute of Technology proposed an ultra-low frequency air spring vibration isolator (Harbin Institute of Technology, "Air Spring Vibration Isolator Based on Electromagnetic Negative Stiffness Structure", Chinese Patent No.: ZL202010605223.6; 2. Ultra-low frequency vibration isolator based on vertically magnetized magnetic ring negative stiffness structure, ZL202010605241.4; 3. Ultra-low frequency air spring vibration isolator based on axially magnetized magnetic ring negative stiffness structure, ZL202010606309.0; 4. High load-bearing ultra-low frequency air spring vibration isolator based on negative stiffness magnetic spring, ZL202010605236.3). This device can achieve negative stiffness characteristics by using magnetic rings that are radially reverse magnetized, axially co-magnetized, or have inner and outer magnetic rings perpendicularly magnetized, and achieve a damping effect by using the eddy currents generated by the relative motion of the inner and outer magnetic rings and the throttling orifice. However, once the above-mentioned device is designed, the negative stiffness and damping value cannot be adjusted. It can only achieve a specific vibration isolation frequency and vibration attenuation effect under constant load, and cannot adapt to changes in load mass, excitation frequency and vibration isolation requirements.

[0007] In summary, developing a device through structural and principle innovation that integrates the control of stiffness and damping in large-scale precision vibration isolation, thereby matching stiffness and damping parameters for near-full-band high-performance vibration isolation, is of great significance for reducing the interference of environmental micro-vibrations on precision instruments and equipment, ensuring optimal working environment for these instruments, and ultimately improving their accuracy. This innovation not only helps optimize the working environment of precision instruments and equipment but also further enhances their accuracy, thus meeting the increasingly stringent demands of scientific research and industrial applications. Summary of the Invention

[0008] This invention aims to address the current lack of research on stiffness and damping control mechanisms in the field of large-scale precision vibration isolation, and designs an integrated negative stiffness and damping control device for large-scale precision vibration isolation. It employs a multi-layered, axially arranged array of uniform-section magnetic rings with perpendicular magnetization between adjacent layers to construct a single-sided high magnetic flux density excitation magnetic field. The perpendicularly magnetized fixed magnetic ring array is coaxially nested with the moving magnetic ring array to achieve high negative stiffness characteristics, and coaxially nested with coils to achieve eddy current damping characteristics. Under the control method based on acceleration and velocity composite feedback, adjustable high negative stiffness and low-frequency high damping, high-frequency low damping characteristics are generated. This precisely matches the stiffness and damping parameters of large-scale precision vibration isolation to achieve near-full-band high-performance vibration isolation, maximizing vibration isolation performance and improving the stability of the isolation system, effectively avoiding the performance bottleneck of single-parameter control.

[0009] The technical solution of this invention is:

[0010] An integrated negative stiffness and damping control device for large-scale precision micro-vibration isolation is disclosed. This device generates adjustable high negative stiffness and low-frequency high damping, high-frequency low damping characteristics to precisely match the stiffness and damping parameters of large-scale precision micro-vibration isolation devices weighing hundreds of tons or more, achieving near-full-band high-performance vibration isolation. Its features include a load platform, a stiffness and damping control device, and a large air-floating micro-vibration isolation device. The large air-floating micro-vibration isolation device includes an upper cover plate, an elastic diaphragm, a cylinder, and compressed gas. The upper cover plate is fixedly connected to the load platform and, together with the elastic diaphragm and cylinder, forms a sealed air chamber. Compressed gas is introduced internally; the stiffness damping control device includes a fixed magnetic ring array, a fixed magnetic ring fixing component, a moving magnetic ring array, a moving magnetic ring fixing component, a coil, a coil frame, a sensor, a signal conditioner, a data acquisition instrument, a controller, and a driver. The fixed magnetic ring fixing component, the fixed magnetic ring array, the moving magnetic ring array, the moving magnetic ring fixing component, the coil frame, and the coil are coaxially nested and arranged sequentially from the axis outward along the radius; the fixed magnetic ring fixing component is a cylindrical structure with an inverted T-shaped cross-section, its bottom is fixed, its top maintains a gap with the load platform, and it is radially connected to the moving magnetic ring array. The moving magnetic ring array and the fixed magnetic ring fixing component have a gap; the fixed magnetic ring array is coaxially nested and tightly fitted on the outer side of the fixed magnetic ring fixing component, and its top end is pressed and fixed by the fixed magnetic ring positioning component, with a gap along the radial direction between it and the moving magnetic ring array and the moving magnetic ring fixing component; the moving magnetic ring fixing component is a cylindrical structure with an opening on the bottom surface, its top end is fixedly connected to the load platform, its bottom end maintains a certain gap with the bottom of the fixed magnetic ring fixing component, and has a gap along the radial direction between it and the coil frame and the coil; the moving magnetic ring array is coaxially nested and tightly fitted on the moving magnetic ring fixing component. On the inner side, its bottom is fixedly connected to the upper surface of the bottom of the moving magnetic ring fixing part, and its top is pressed and fixed by the moving magnetic ring positioning part. A gap is provided radially between it and the coil frame and coil. The coil frame is an annular sleeve with a deep groove along the circumference of its outer cylindrical surface. Its bottom is fixed, and its top maintains a certain gap with the load platform. The coil is coaxially nested and tightly fitted and fixedly installed in the annular deep groove on the outer side of the coil frame. Both the fixed magnetic ring array and the moving magnetic ring array are composed of multiple layers of uniform cross-section magnetic rings arranged axially and perpendicularly magnetized between adjacent layers, with two layers in each array. n +1, n ≥1, n∈N +In this system, the odd-numbered magnetic rings are all of equal height, and the even-numbered magnetic rings are all of equal height. The first layer of the fixed magnetic ring array and the moving magnetic ring array are magnetized in opposite directions radially. On the right half of the front sectional view, with each additional layer, the magnetization direction of the fixed magnetic ring rotates 90° clockwise, and the magnetization direction of the moving magnetic ring rotates 90° counterclockwise. The sensor is fixedly connected to the load platform. Its output signal is transmitted to the controller by the acquisition instrument after passing through the signal conditioner. The controller processes the signal using a composite acceleration and velocity feedback control algorithm and outputs a control voltage to the driver. The driver converts the control voltage into a control current, which drives the coil to generate a control force acting on the load platform. Specifically, the controller analyzes and accurately calculates the vibration signal based on the load mass or excitation frequency change using a composite acceleration and velocity control algorithm to generate a control voltage. The driver converts the control voltage into a control current of the control coil, thereby adjusting the excitation magnetic field and changing the negative stiffness and damping value of the stiffness and damping control device.

[0011] Preferably, the stiffness damping adjustment device is arranged with an adjacent gap to the large air-bearing micro-vibrator, or the stiffness damping adjustment device is coaxially nested and fixedly installed in the cylinder of the large air-bearing micro-vibrator.

[0012] Preferably, the height of the magnetic rings in the same layer of the fixed magnetic ring array and the moving magnetic ring array is equal, and the height of the coil is equal to that of the fixed magnetic ring array and the moving magnetic ring array.

[0013] Preferably, the bottom of the first layer of magnetic rings in the fixed magnetic ring array coincides with the bottom of the first layer of magnetic rings in the moving magnetic ring array.

[0014] Preferably, the large air-float micro-vibrator adopts a steel ring seal, O-ring seal, diaphragm seal, or pressure self-sealing method.

[0015] Preferably, the pressure of the compressed gas is 0.1 MPa to 0.8 MPa.

[0016] Preferably, the cylinder is connected in series with multiple sealed auxiliary air tanks via throttle holes or air pipes.

[0017] Preferably, the radially magnetized magnetic rings in the fixed magnetic ring array and the moving magnetic ring array are composed of multiple radially uniformly magnetized tile-shaped magnets spliced ​​together. The number of tile-shaped magnets is 4, 5, 6, 8, 10, 12 or 15, and the gap between adjacent tile-shaped magnets does not exceed 3°.

[0018] Preferably, the sensor is a combination of a velocity sensor and an acceleration sensor.

[0019] Preferably, the number of throttling orifices between adjacent auxiliary gas tanks are different and their positions do not overlap.

[0020] Preferably, the throttling orifice is triangular, circular, pentagonal, or other polygonal in shape.

[0021] Preferably, the velocity sensor and the acceleration sensor are magnetoelectric, piezoelectric, or inertial sensors.

[0022] Preferably, the coil frame is made of carbon fiber composite material or rigid plastic material.

[0023] Preferably, the coil frame is made of boron nitride ceramic, nanodiamond, or fiberglass.

[0024] Preferably, the signal conditioner includes an amplifier and a filter, wherein the amplifier has an adjustable amplification factor and the filter is a high-pass filter with an adjustable cutoff frequency.

[0025] Preferably, the fixed magnetic ring fixing component, the moving magnetic ring fixing component, the fixed magnetic ring positioning component, and the moving magnetic ring positioning component are all made of non-magnetic or weakly magnetic aluminum alloy or titanium alloy.

[0026] The technical innovation and positive effects of this invention are as follows:

[0027] (1) This invention innovatively proposes a large-scale precision micro-vibration isolation stiffness and damping control device based on a vertically magnetized magnetic ring array. By innovating the stiffness and damping control configuration composed of a parallel magnetized magnetic array in a two-dimensional plane, a three-dimensional vertically magnetized magnetic ring array is used to construct a single-sided high magnetic density excitation magnetic field. Through advanced control algorithms and sensor feedback, adjustable high negative stiffness and eddy current damping characteristics are achieved, greatly improving the magnetic field utilization and energy conversion efficiency, and providing a configurational basis for stiffness and damping control of large-scale precision micro-vibration isolation devices of hundreds of tons or more. This is one of the innovative points of this invention that distinguishes it from the prior art.

[0028] (2) This invention achieves integrated control of the stiffness and damping parameters of large-scale precision vibration isolation systems. By generating adjustable high negative stiffness and low-frequency high damping, high-frequency low damping characteristics, the stiffness and damping of large-scale precision vibration isolation platforms weighing hundreds of tons or more are integratedly controlled. This allows for matching stiffness and damping parameters to achieve near-full-band vibration isolation and full-frequency domain high-performance vibration isolation, thereby expanding the isolation bandwidth, improving vibration isolation performance, and achieving near-full-band high-performance vibration isolation. This integrated control design effectively avoids the performance bottleneck problem that single-parameter control can lead to, giving large-scale precision vibration isolation systems stronger environmental adaptability and dynamic adjustment capabilities, enabling them to better adapt to complex challenges such as load mass changes, excitation frequency fluctuations, and diverse vibration isolation requirements. This is the second innovative point that distinguishes this invention from the prior art.

[0029] (3) This invention can improve the vibration isolation performance and stability of large-scale precision micro-vibration isolation systems. Vibration isolation systems based on single-parameter control of stiffness or damping may encounter performance bottlenecks and stability problems in certain situations. For example, adjusting only one parameter often fails to simultaneously meet multiple vibration isolation requirements such as isolation frequency band and vibration attenuation rate. Improper stiffness and damping parameter settings or excessive external excitation may lead to system instability. Integrated control achieves near-full-band high-performance vibration isolation stiffness and damping through matching, maximizing vibration isolation performance and improving the stability of the vibration isolation system. This helps reduce the amplification of vibrations caused by mismatched stiffness and damping parameters or external interference. This is the third innovative point that distinguishes this invention from existing technologies.

[0030] (4) This invention has the advantages of compact structure, convenient installation, and low maintenance cost. The core advantage of the stiffness-damping control device is that it can simultaneously generate adjustable high negative stiffness and low-frequency high damping and high-frequency low damping characteristics, avoiding the complex combination of independent negative stiffness structure and damping structure in existing methods. Through integrated design, not only is the system volume and weight significantly reduced, making the overall structure more compact and saving installation space; in addition, by reducing the connecting parts between different components, the system complexity is reduced, while potential failure points and maintenance difficulties are effectively reduced, resulting in low installation and maintenance costs and improved reliability and stability. This is the fourth innovative point of this invention that distinguishes it from the prior art. Attached Figure Description

[0031] Figure 1 A three-dimensional view of the stiffness damping control device;

[0032] Figure 2 This is a frontal cross-sectional view of the stiffness-damping control device.

[0033] Figure 3 A three-dimensional diagram of Example 1 of a negative stiffness damping integrated control device for large-scale precision micro-vibration isolation.

[0034] Figure 4 This is a front cross-sectional view of Embodiment 1 of an integrated negative stiffness damping control device for large-scale precision micro-vibration isolation.

[0035] Figure 5 A three-dimensional diagram of Embodiment 2 of a negative stiffness damping integrated control device for large-scale precision micro-vibration isolation;

[0036] Figure 6 This is a front cross-sectional view of Embodiment 2 of a negative stiffness damping integrated control device for large-scale precision micro-vibration isolation.

[0037] Figure 7 A front cross-sectional view of a large air-float micro-vibration isolator when the cylinder is connected in series with multiple auxiliary air tanks via air pipes.

[0038] Figure 8 A front cross-sectional view of a large air-float micro-vibrator when the cylinder and multiple auxiliary air tanks are connected in series through throttle holes.

[0039] Part numbers in the diagram: 1 Ground, 2 Fixed magnetic ring array, 3 Fixed magnetic ring fixture, 4 Moving magnetic ring array, 5 Moving magnetic ring fixture, 6 Coil, 7 Coil frame, 8 Load platform, 9 Sensor, 10 Signal conditioner, 11 Acquisition device, 12 Controller, 13 Driver, 14 Stiffness damping control device, 15 Large air-bearing micro-vibrator, 16 Top cover plate, 17 Elastic membrane, 18 Cylinder, 19 Compressed gas, 20 Throttling orifice, 21 Auxiliary gas tank, 22 Fixed magnetic ring positioning component, 23 Moving magnetic ring positioning component, 24 Gas pipe. Detailed Implementation

[0040] The specific embodiments of the present invention will now be described in detail with reference to the accompanying drawings.

[0041] An integrated negative stiffness and damping control device for large-scale precision micro-vibration isolation, by generating adjustable high negative stiffness and low-frequency high damping and high-frequency low damping characteristics, precisely matches the stiffness and damping parameters of large-scale precision micro-vibration isolation devices weighing hundreds of tons or more to achieve near-full-band high-performance vibration isolation. It includes a load platform 8, a stiffness and damping control device 14, and a large air-floating micro-vibration isolation device 15. The large air-floating micro-vibration isolation device 15 includes an upper cover plate 16, an elastic diaphragm 17, a cylinder 18, and compressed gas 19. The upper cover plate 16 is fixedly connected to the load platform 8, forming a sealed air chamber with the elastic diaphragm 17 and the cylinder 18. Compressed gas 19 is introduced; the stiffness damping control device 14 includes a fixed magnetic ring array 2, a fixed magnetic ring fixing component 3, a moving magnetic ring array 4, a moving magnetic ring fixing component 5, a coil 6, a coil frame 7, a sensor 9, a signal conditioner 10, a data acquisition device 11, a controller 12, and a driver 13. The fixed magnetic ring fixing component 3, the fixed magnetic ring array 2, the moving magnetic ring array 4, the moving magnetic ring fixing component 5, the coil frame 7, and the coil 6 are coaxially nested and arranged sequentially from the axis outward along the radius; the fixed magnetic ring fixing component 3 is a cylindrical structure with an inverted T-shaped cross-section, its bottom is fixed, and its top maintains a gap with the load platform 8. The moving magnetic ring array 4 and the moving magnetic ring fixing member 5 are provided with a radial gap; the fixed magnetic ring array 2 is coaxially nested and tightly fitted on the outer side of the fixed magnetic ring fixing member 3, and its top end is pressed and fixed by the fixed magnetic ring positioning member 22, and is provided with a radial gap from the moving magnetic ring array 4 and the moving magnetic ring fixing member 5; the moving magnetic ring fixing member 5 is a cylindrical structure with an opening on the bottom surface, its top end is fixedly connected to the load platform 8, its bottom end maintains a certain gap with the bottom of the fixed magnetic ring fixing member 3, and is provided with a radial gap from the coil frame 7 and the coil 6; the moving magnetic ring array 4 is coaxially nested and tightly fitted on the moving magnetic ring array 4 and the moving magnetic ring fixing member 5. The inner side of the fixing member 5 is fixedly connected to the upper surface of the bottom of the moving magnetic ring fixing member 5, and the top is pressed and fixed by the moving magnetic ring positioning member 23. It has a gap with the coil frame 7 and the coil 6 in the radial direction. The coil frame 7 is an annular sleeve with a deep groove on the outer cylindrical surface. Its bottom is fixed and its top maintains a certain gap with the load platform 8. The coil 6 is coaxially nested and tightly fitted and fixedly installed in the annular deep groove on the outer side of the coil frame 7. The fixed magnetic ring array 2 and the moving magnetic ring array 4 are both composed of multiple layers of magnetic rings with equal cross-sections arranged in an axial array and perpendicularly magnetized between adjacent layers. The number of layers is 2. n +1, n ≥1, n∈N +In this configuration, the odd-numbered magnetic rings have the same height, and the even-numbered magnetic rings have the same height. The first layer of the fixed magnetic ring array 2 and the moving magnetic ring array 4 are magnetized in opposite directions radially. On the right half of the front cross-sectional view, with each additional layer, the magnetization direction of the fixed magnetic ring rotates 90° clockwise, and the magnetization direction of the moving magnetic ring rotates 90° counterclockwise. The sensor 9 is fixedly connected to the load platform 8. Its output signal is transmitted to the controller 12 by the acquisition instrument 11 after passing through the signal conditioner 10. The controller 12 processes the signal using a composite acceleration and velocity feedback control algorithm and outputs a control voltage to the driver 13. The driver 13 converts the control voltage into a control current, which drives the coil 6 to generate a control force acting on the load platform 8. The controller 12 generates a control voltage by analyzing and accurately calculating the vibration signal based on the load mass or excitation frequency change using a composite acceleration and velocity control algorithm. The driver 13 converts the control voltage into a control current of the control coil 6, thereby adjusting the excitation magnetic field and changing the negative stiffness and damping value of the stiffness and damping control device 14.

[0042] As a specific implementation, the stiffness damping control device 14 is arranged with an adjacent gap to the large air-bearing micro-vibrator 15, or the stiffness damping control device 14 is coaxially nested and fixedly installed in the cylinder 18 of the large air-bearing micro-vibrator 15.

[0043] In one specific implementation, the fixed magnetic ring array 2 and the magnetic rings in the same layer of the moving magnetic ring array 4 have the same height, and the coil 6 has the same height as the fixed magnetic ring array 2 and the moving magnetic ring array 4.

[0044] In one specific implementation, the bottom of the first layer of magnetic rings in the fixed magnetic ring array 2 coincides with the bottom of the first layer of magnetic rings in the moving magnetic ring array 4.

[0045] As a specific implementation method, the large air-floating micro-vibrator 15 adopts a steel ring seal, O-ring seal, diaphragm seal or pressure self-sealing method.

[0046] In one specific implementation, the pressure of the compressed gas 19 is 0.1 MPa to 0.8 MPa.

[0047] In one specific implementation, the cylinder 18 is connected in series with multiple sealed auxiliary air tanks 21 via throttle holes 20 or air pipes 24.

[0048] In one specific implementation, the radially magnetized magnetic rings in the fixed magnetic ring array 2 and the moving magnetic ring array 4 are composed of multiple radially uniformly magnetized tile-shaped magnets spliced ​​together. The number of tile-shaped magnets is 4, 5, 6, 8, 10, 12 or 15, and the gap between adjacent tile-shaped magnets does not exceed 3°.

[0049] In one specific implementation, sensor 9 is a combination of a velocity sensor and an acceleration sensor.

[0050] In one specific implementation, the number of throttle orifices 20 between adjacent auxiliary gas tanks 21 is different and their positions do not overlap.

[0051] As one specific implementation, the throttling orifice 20 is triangular, circular, pentagonal, or other polygonal in shape.

[0052] As one specific implementation method, the velocity sensor and acceleration sensor are magnetoelectric, piezoelectric, or inertial sensors.

[0053] In one specific implementation, the coil frame 7 is made of carbon fiber composite material or rigid plastic material.

[0054] In one specific implementation, the coil frame 7 is made of boron nitride ceramic, nanodiamond, or fiberglass.

[0055] In one specific implementation, the signal conditioner 10 includes an amplifier and a filter. The amplifier's amplification factor is adjustable, and the filter is a high-pass filter with an adjustable cutoff frequency.

[0056] In one specific implementation, the fixed magnetic ring fixing component 3, the moving magnetic ring fixing component 5, the fixed magnetic ring positioning component 22, and the moving magnetic ring positioning component 23 are all made of non-magnetic or weakly magnetic aluminum alloy or titanium alloy.

[0057] The following is combined with Figures 1-4 An embodiment of the present invention is given.

[0058] The integrated negative stiffness damping control device for large-scale precision micro-vibration isolation consists of a load platform 8, a stiffness damping control device 14, and a large air-bearing micro-vibration isolator 15. The stiffness damping control device 14 and the large air-bearing micro-vibration isolator 15 are arranged with adjacent gaps and connected in parallel to support the load platform 8. The large air-bearing micro-vibration isolator 15 stably supports the load platform 8, which is over 100 tons, in a passive air-bearing manner, and effectively isolates it from mid-to-high frequency vibrations. The stiffness and damping control device 14 utilizes active magnetic levitation to generate adjustable high negative stiffness and low-frequency high damping and high-frequency low damping characteristics. It is connected in parallel with the large air-floating micro-vibration isolator 15 to support the load platform 8. It can integrate the stiffness and damping of large precision micro-vibration isolators weighing hundreds of tons or more without affecting the load-bearing capacity. This allows for the matching and achievement of near-full-band high-performance vibration isolation stiffness and low-frequency high damping and high-frequency low damping parameters. It generates local near-zero stiffness and near-zero transmissivity characteristics, reduces the natural frequency of vibration isolation, expands the vibration isolation bandwidth, and improves the vibration attenuation rate. This maximizes the vibration isolation performance and improves the stability of the vibration isolation system, providing an "ultra-quiet" working environment for cutting-edge instruments and equipment such as ultra-precision lithography machines, high-resolution satellite cameras, and ultra-precision machine tools.

[0059] The large-scale air-float micro-vibration isolator 15, as the core equipment of ultra-precision air-float micro-vibration isolation technology, is a non-metallic spring that uses compressed gas 19 filled into an elastic diaphragm 17 to achieve elastic support through the compressibility of the gas. Structurally, the large-scale air-float micro-vibration isolator 15 consists of an upper cover plate 16, an elastic diaphragm 17, a cylinder 18, and compressed gas 19. The upper cover plate 16 is fixedly connected to the load platform 8 and forms a sealed air chamber with the elastic diaphragm 17 and the cylinder 18 through steel ring sealing, O-ring sealing, diaphragm sealing, or pressure self-sealing. Compressed gas 19 at a pressure of 0.1MPa to 0.8MPa is introduced into the sealed air chamber. When external micro-vibration interference acts on the large-scale air-float micro-vibration isolator 15, the compressed gas 19 in the sealed air chamber will be compressed and expanded accordingly according to the frequency and amplitude of the micro-vibration, thereby effectively absorbing and dissipating vibration energy and achieving vibration isolation. At the same time, by adjusting the pressure of the compressed gas 19 in the sealed air chamber, stable support for different load capacities and high-performance mid-to-high frequency band vibration isolation effects can be achieved.

[0060] The stiffness damping control device 14 includes a fixed magnetic ring array 2, a fixed magnetic ring fixing component 3, a moving magnetic ring array 4, a moving magnetic ring fixing component 5, a coil 6, a coil frame 7, a sensor 9, a signal conditioner 10, a data acquisition unit 11, a controller 12, and a driver 13. The fixed magnetic ring fixing component 3, the fixed magnetic ring array 2, the moving magnetic ring array 4, the moving magnetic ring fixing component 5, the coil frame 7, and the coil 6 are coaxially nested and arranged sequentially from the axis outwards along the radius. The fixed magnetic ring fixing component 3 is a cylindrical structure with an inverted T-shaped cross-section. Its bottom is fixed, and its top maintains a gap of 30mm to 100mm with the load platform 8. This gap is greater than the sum of the buoyancy height of the large air-bearing micro-vibrator 15 and the maximum vibration amplitude of the load platform 8. The fixed magnetic ring fixing component 3 has a gap along the radial direction with the moving magnetic ring array 4 and the moving magnetic ring fixing component 5. The fixed magnetic ring array 2 is coaxially nested and tightly fitted on the outer side of the fixed magnetic ring fixing component 3. Its top end is pressed and fixed by the fixed magnetic ring positioning component 22, and there is a gap in the radial direction between it and the moving magnetic ring array 4 and the moving magnetic ring fixing component 5. The moving magnetic ring fixing component 5 is a cylindrical structure with an opening on the bottom surface. Its top end is fixedly connected to the load platform 8, and its bottom end maintains a gap of 30mm to 100mm with the bottom end of the fixed magnetic ring fixing component 3. There is a gap in the radial direction between it and the coil frame 7 and the coil 6. The moving magnetic ring array 4 is coaxially nested and tightly fitted on the inner side of the moving magnetic ring fixing component 5. Its bottom end is fixedly connected to the upper surface of the bottom of the moving magnetic ring fixing component 5, and its top end is pressed and fixed by the moving magnetic ring positioning component 23. There is a gap in the radial direction between it and the coil frame 7 and the coil 6. Among them, the fixed magnetic ring fixing component 3, the moving magnetic ring fixing component 5, the fixed magnetic ring positioning component 22, and the moving magnetic ring positioning component 23 are all made of aluminum alloy or titanium alloy. The coil frame 7 is made of carbon fiber composite material, hard plastic material, boron nitride ceramic, nano diamond, or fiberglass material.

[0061] Both the fixed magnetic ring array 2 and the moving magnetic ring array 4 consist of multiple layers of uniform cross-section magnetic rings arranged axially and perpendicularly magnetized between adjacent layers. The magnetic rings are all N44H grade neodymium iron boron permanent magnets with a remanence of 13.54 kGs, an intrinsic coercivity of 12.66 kOe, and a relative permeability of [missing information]. μ r =1.23. The inner and outer radii of the fixed magnetic ring array 2 are 13mm and 64mm, respectively. The height of the odd-numbered layers of fixed magnetic rings is 20mm, and the height of the even-numbered layers is 34mm. The inner and outer radii of the moving magnetic ring array 4 are 70mm and 100mm, respectively. The height of the odd-numbered layers of moving magnetic rings is 20mm, and the height of the even-numbered layers is 34mm. The first layer of fixed magnetic rings is magnetized radially towards the axis, and the first layer of moving magnetic rings is magnetized radially outward from the axis. On the right half of the front sectional view, with each additional layer of magnetic rings, the magnetization direction of the fixed magnetic rings rotates 90° clockwise, and the magnetization direction of the moving magnetic rings rotates 90° counterclockwise. The radially magnetized magnetic rings in both the fixed magnetic ring array 2 and the moving magnetic ring array 4 are composed of eight 42° tile-shaped magnets spliced ​​together, with a gap of 3° between adjacent tile-shaped magnets.

[0062] The coil frame 7 is an annular sleeve with a deep groove along its circumference on its outer cylindrical surface. Its bottom is fixed, and its top maintains a gap of 30mm to 100mm with the load platform 8. The coil 6 is coaxially nested and tightly fitted within the annular deep groove on the outer side of the coil frame 7. The coil 6 is made of copper wire wound turn by turn, with a wire diameter of not less than 0.25mm and not more than 2mm. Each layer or section of copper wire is insulated with insulating varnish, insulating paper, or insulating sleeves to prevent short circuits. The height of the coil 6 is equal to that of the fixed magnetic ring array 2 and the moving magnetic ring array 4. The current carrying capacity does not exceed 10A. Heat dissipation efficiency can be improved by increasing the heat dissipation area of ​​the coil 6 surface (e.g., using heat sinks or increasing airflow). Alternatively, efficient cooling methods such as liquid cooling or phase change cooling can be used to quickly and effectively dissipate the heat generated during coil 6's operation, preventing overheating. Sensor 9 is a combination of a magnetoelectric, piezoelectric, or inertial velocity sensor and an accelerometer. It collects the vibration of the load platform 8 in real time. The vibration signal is processed by a signal conditioner 10 with integrated amplification and filtering functions, and then transmitted to the controller 12 by the acquisition unit 11. The amplification factor of the signal conditioner 10 is adjustable, and the filter implements a high-pass filtering function with an adjustable cutoff frequency. The controller 12 has a built-in precision control algorithm for composite acceleration and velocity feedback. After analyzing and accurately calculating the received signal, it generates a control voltage. This control voltage is output to the driver 13 through the analog output function of the acquisition unit 11. The driver 13 converts the control voltage into a control current that acts on the coil 6.

[0063] Since the number of layers of the fixed magnetic ring array 2 and the moving magnetic ring array 4 satisfies 2 n +1 ( n ≥1, n∈N + ), the overall structure about the first n The +1 layer of magnetic rings is symmetrical vertically, and the magnetic force on the moving magnetic ring array 4 is zero, placing it in equilibrium. Under axial micro-perturbation excitation, the moving magnetic ring array 4 and the fixed magnetic ring array 2 will undergo relative motion. At this time, the axial equilibrium of the moving magnetic ring array 4 is broken, while the radial equilibrium remains. The axial magnetic force of the fixed magnetic ring array 2 acting on the moving magnetic ring array 4 is in the same direction as the vibration, causing it to continue moving away from the equilibrium position. Without external force, the equilibrium cannot be restored, meaning its axial magnetic force exhibits negative stiffness characteristics. When the moving magnetic ring array 4 moves relative to the coil 6, the magnetic flux through the coil 6 changes. Under the coupling effect of the magnetic and electric fields, the moving magnetic ring array 4 experiences a damping force that is positively correlated with the velocity and opposite in direction, thereby converting vibrational energy into electrical energy and dissipating it as heat. When the number of layers of the fixed magnetic ring array 2 and the moving magnetic ring array 4 is 3 and the current flowing through the coil 6 is 0, the stiffness damping control device 14 with the above four structural parameters can reduce the stiffness of the 53.13-ton large air-floating micro-vibration isolation platform by 28.40%, increase the attenuation rate of random vibration of the ground 1 from 70.85% to 75.44%, and reduce the peak vibration transmissibility from 15.61dB to 3.94dB, an attenuation of 74.76%, thereby expanding the vibration isolation bandwidth and improving the vibration isolation performance. When the load mass or excitation frequency changes, the controller 12 uses a precision control algorithm of composite acceleration and velocity feedback to analyze and accurately calculate the vibration signal to generate a control voltage. The driver 13 converts the control voltage into the control current of the control coil 6, thereby adjusting the excitation magnetic field and changing the negative stiffness and damping value of the stiffness damping control device 14 to match and achieve near-full-band high-performance vibration isolation stiffness and damping parameters. Therefore, the stiffness damping control device 14 does not affect the load-bearing capacity of the large precision vibration isolation platform. It only controls the vibration isolation bandwidth and vibration isolation effect by generating negative stiffness and damping characteristics, thereby achieving a high-performance vibration isolation effect across the entire frequency band.

[0064] Figure 5 and Figure 6The figures are a three-dimensional view and a front cross-sectional view of Embodiment 2 of the integrated negative stiffness damping control device for large-scale precision micro-vibration isolation. The stiffness damping control device 14 is coaxially nested and fixedly installed in the cylinder 18 of the large air-float micro-vibration isolation device 15, and is connected in parallel with the large air-float micro-vibration isolation device 15 to support the load platform 8. In the stiffness damping control device 14, the fixed magnetic ring array 2, the moving magnetic ring array 4, and the coil 6 are coaxially nested and tightly fitted onto the fixed magnetic ring fixing member 3, the moving magnetic ring fixing member 5, and the coil frame 7, respectively. The bottom of the fixed magnetic ring fixing member 3 and the coil frame 7 are fixedly connected to the upper surface of the lower base plate of the cylinder 18, and their tops maintain a gap of 30mm to 100mm with the bottom of the upper cover plate 16. This gap is greater than the sum of the floating height of the large air-bearing micro-vibrator 15 and the maximum vibration amplitude of the load platform 8. The top of the moving magnetic ring fixing member 5 is fixedly connected to the bottom of the upper cover plate 16, and its bottom maintains a gap of 30mm to 100mm with the upper surface of the lower base plate of the cylinder 18.

[0065] Figure 7 and Figure 8 Two specific embodiments of the large air-float micro-vibrator 15 are provided. In both designs, the cylinder 18 of the large air-float micro-vibrator 15 is connected to the air pipe 24 or the throttle orifice 20. m The auxiliary gas cylinders 21 are connected in series. The number and position of the throttling orifices 20 between adjacent auxiliary gas cylinders 21 differ. These two structures are suitable for applications with large horizontal or vertical installation space, respectively. Both the gas pipe 24 and the throttling orifices 20 limit the gas flow rate, enabling the large precision vibration isolation system to respond more stably to external vibrations. By adjusting the diameter or length of the gas pipe 24, and the number, size, and shape of the throttling orifices 20, the vibration isolation damping characteristics can be optimized to meet different vibration isolation requirements.

Claims

1. An integrated negative stiffness and damping control device for large-scale precision micro-vibration isolation, which generates adjustable high negative stiffness and low-frequency high damping, high-frequency low damping characteristics to precisely match the stiffness and damping parameters of large-scale precision micro-vibration isolation devices weighing hundreds of tons or more, achieving near-full-band high-performance vibration isolation; characterized in that... The system includes a load platform (8), a stiffness and damping control device (14), and a large air-float micro-vibrator (15). The large air-float micro-vibrator (15) includes an upper cover plate (16), an elastic membrane (17), a cylinder (18), and compressed gas (19). The upper cover plate (16) is fixedly connected to the load platform (8) and forms a sealed air chamber with the elastic membrane (17) and the cylinder (18). Compressed gas (19) is introduced into the sealed air chamber. The stiffness and damping control device (14) includes a fixed magnetic ring array (2), a fixed magnetic ring fixing component (3), a moving magnetic ring array (4), a moving magnetic ring fixing component (5), and a coil. (6) Coil frame (7) Sensor (9) Signal conditioner (10) Acquisition unit (11) Controller (12) and driver (13), fixed magnetic ring fixing part (3), fixed magnetic ring array (2) Moving magnetic ring array (4) Moving magnetic ring fixing part (5), coil frame (7) and coil (6) are coaxially nested and arranged outward from the axis along the radius; the fixed magnetic ring fixing part (3) is a cylindrical structure with an inverted T-shaped cross section, its bottom is fixed, its top is kept with the load platform (8) with a gap, and it has a gap along the radial direction with the moving magnetic ring array (4) and the moving magnetic ring fixing part (5); the fixed magnetic ring array (2) The magnetic ring is coaxially nested and tightly fitted on the outer side of the fixed magnetic ring fixing part (3), and its top end is pressed and fixed by the fixed magnetic ring positioning part (22). It has a gap in the radial direction with the moving magnetic ring array (4) and the moving magnetic ring fixing part (5). The moving magnetic ring fixing part (5) is a cylindrical structure with a hole on the bottom surface. Its top end is fixedly connected to the load platform (8), and its bottom end maintains a certain gap with the bottom of the fixed magnetic ring fixing part (3). It has a gap in the radial direction with the coil frame (7) and the coil (6). The moving magnetic ring array (4) is coaxially nested and tightly fitted on the inner side of the moving magnetic ring fixing part (5). Its bottom end is fixedly fitted on the outer side of the fixed magnetic ring fixing part (5). The part is fixedly connected to the upper surface of the bottom of the moving magnetic ring fixing part (5), and the top end is pressed and fixed by the moving magnetic ring positioning part (23). There is a gap between it and the coil frame (7) and the coil (6) in the radial direction. The coil frame (7) is an annular sleeve with a deep groove on the outer cylindrical surface along the circumference. Its bottom is fixed and its top end maintains a certain gap with the load platform (8). The coil (6) is coaxially nested and tightly fitted and fixedly installed in the annular deep groove on the outer side of the coil frame (7). The fixed magnetic ring array (2) and the moving magnetic ring array (4) are both composed of multiple layers of axially arranged magnetic rings with perpendicular magnetization between adjacent layers and equal cross-section magnetic rings. The number of layers is 2. n +1, n ≥1, n∈N + In this configuration, the odd-numbered magnetic rings are all of equal height, and the even-numbered magnetic rings are all of equal height. The first layer of the fixed magnetic ring array (2) and the moving magnetic ring array (4) are magnetized in opposite directions radially. On the right half of the front cross-sectional view, with each additional layer, the magnetization direction of the fixed magnetic ring rotates 90° clockwise, and the magnetization direction of the moving magnetic ring rotates 90° counterclockwise. The sensor (9) is fixedly connected to the load platform (8), and its output signal is transmitted to the controller (12) by the acquisition instrument (11) after passing through the signal conditioner (10). The controller (12) uses a composite acceleration and velocity feedback control algorithm to process the signal. After processing, the output control voltage is transmitted to the driver (13), the driver (13) converts the control voltage into control current, and the driving coil (6) generates control force to act on the load platform (8); wherein, the controller (12) generates control voltage by analyzing and accurately calculating the vibration signal according to the load mass or excitation frequency change, using a control algorithm based on acceleration and velocity composite, and the driver (13) converts the control voltage into control current of the regulating coil (6), thereby adjusting the excitation magnetic field and changing the negative stiffness and damping value of the stiffness damping regulating device (14).

2. The integrated negative stiffness damping control device for large-scale precision micro-vibration isolation as described in claim 1, characterized in that: The stiffness damping control device (14) is arranged with an adjacent gap to the large air-float micro-vibrator (15) or the stiffness damping control device (14) is coaxially nested and fixedly installed in the cylinder (18) of the large air-float micro-vibrator (15).

3. The integrated negative stiffness damping control device for large-scale precision micro-vibration isolation as described in claim 1, characterized in that: The fixed magnetic ring array (2) and the moving magnetic ring array (4) have the same height of magnetic rings in the same layer, and the coil (6) has the same height as the fixed magnetic ring array (2) and the moving magnetic ring array (4).

4. The integrated negative stiffness damping control device for large-scale precision micro-vibration isolation as described in claim 1, characterized in that: The bottom of the first layer of magnetic rings in the fixed magnetic ring array (2) coincides with the bottom of the first layer of magnetic rings in the moving magnetic ring array (4).

5. The integrated negative stiffness damping control device for large-scale precision micro-vibration isolation as described in claim 1, characterized in that: The large air-float micro-vibrator (15) adopts steel ring sealing, O-ring sealing, diaphragm sealing or pressure self-sealing.

6. The integrated negative stiffness damping control device for large-scale precision micro-vibration isolation as described in claim 1, characterized in that: The pressure of the compressed gas (19) is 0.1 MPa to 0.8 MPa.

7. The integrated negative stiffness damping control device for large-scale precision micro-vibration isolation as described in claim 1, characterized in that: The cylinder (18) is connected in series with multiple sealed auxiliary air tanks (21) through a throttle orifice (20) or an air pipe (24).

8. The integrated negative stiffness damping control device for large-scale precision micro-vibration isolation as described in claim 1, characterized in that: The radially magnetized magnetic rings in the fixed magnetic ring array (2) and the moving magnetic ring array (4) are composed of multiple radially uniformly magnetized tile-shaped magnets spliced ​​together. The number of tile-shaped magnets is 4, 5, 6, 8, 10, 12 or 15, and the gap between adjacent tile-shaped magnets does not exceed 3°.

9. The integrated negative stiffness damping control device for large-scale precision micro-vibration isolation as described in claim 1, characterized in that: The sensor (9) is a combination of a velocity sensor and an acceleration sensor.

10. The integrated negative stiffness damping control device for large-scale precision micro-vibration isolation as described in claim 7, characterized in that: The number of throttle orifices (20) between adjacent auxiliary gas tanks (21) is different and their positions do not overlap.

11. The integrated negative stiffness damping control device for large-scale precision micro-vibration isolation as described in claim 7, characterized in that: The throttling orifice (20) is triangular, circular, pentagonal, or other polygonal in shape.

12. The integrated negative stiffness damping control device for large-scale precision micro-vibration isolation as described in claim 9, characterized in that: The velocity sensor and acceleration sensor are magnetoelectric, piezoelectric, or inertial sensors.

13. The integrated negative stiffness damping control device for large-scale precision micro-vibration isolation as described in claim 1, characterized in that: The coil frame (7) is made of carbon fiber composite material or rigid plastic material.

14. The integrated negative stiffness damping control device for large-scale precision micro-vibration isolation as described in claim 1, characterized in that: The coil frame (7) is made of boron nitride ceramic, nano diamond or fiberglass.

15. The integrated negative stiffness damping control device for large-scale precision micro-vibration isolation as described in claim 1, characterized in that: The signal conditioner (10) includes an amplifier and a filter. The amplifier's amplification factor is adjustable, and the filter is a high-pass filter. Its cutoff frequency is adjustable.

16. The integrated negative stiffness damping control device for large-scale precision micro-vibration isolation as described in claim 1, characterized in that: The fixed magnetic ring fixing component (3), the moving magnetic ring fixing component (5), the fixed magnetic ring positioning component (22), and the moving magnetic ring positioning component (23) are all made of non-magnetic or weakly magnetic aluminum alloy or titanium alloy.

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