Composite negative stiffness mechanical connection device between structures and multi-parameter determination method

Abstract

The invention discloses an inter-structure composite negative stiffness mechanical connection device and a multi-parameter determination method. The inter-structure composite negative stiffness mechanical connection device comprises a first negative stiffness generation device, a second negative stiffness generation device, a force transmission device, a first connection device and a second connection device. The transmission force device is provided with four branches, namely a first branch and a second branch which are opposite to each other, and a third branch and a fourth branch which are opposite to each other; the first branch is connected with the structure A, the second branch is connected with the structure B, the third branch is connected with the first negative stiffness generating device, and the fourth branch is connected with the second negative stiffness generating device; the end, away from the transmission force device, of the first negative stiffness generating device is connected with the structure A and the structure B through a first connecting device. The end, away from the transmission force device, of the second negative stiffness generating device is connected with the structure A and the structure B through a second connecting device. The first negative stiffness generating device and the second negative stiffness generating device are the same in structure and each comprise a pre-pressing negative stiffness large arm and a pre-pressing negative stiffness small arm. The pre-pressing negative stiffness small arm and the pre-pressing negative stiffness large arm are the same in structure and are reduced in size. The multi-parameter determination method is used for obtaining related design parameters of the pre-pressing negative stiffness large arm and related design parameters of the pre-pressing negative stiffness small arm according to the negative stiffness needed between the structure A and the structure B. The structure connected through the negative stiffness connecting device has the advantages of being wide in vibration reduction frequency band, low in amplitude-frequency peak value and the like.

Description

Technical Field

[0001] This invention relates to a composite negative stiffness mechanical connection device between structures and a method for determining multiple parameters, belonging to the field of structural vibration control. Background Technology

[0002] With the increasing density of urban buildings and the growing demand for the renovation and expansion of existing buildings, more and more structures need to be connected using connection devices to achieve the corresponding architectural and structural functions.

[0003] While traditional rigid connection devices have solved the problem of ensuring a secure connection between structures to some extent, they significantly alter the dynamic characteristics of the connected structures and have poor energy dissipation capabilities. With the continuous development of inter-structural connection devices, current devices generally employ flexible or energy-dissipating mechanisms. For example, CN202323418632.3 and CN202321298429.4 respectively provide a flexible inter-structural connection device and a vibration-damping inter-structural connection device. These devices can minimize the impact on the dynamic characteristics of the connected structures and possess a certain energy dissipation capability. However, these devices still cannot enable the connected structures to perform tuned vibration reduction functions, nor can they promote vibration reduction and energy dissipation, resulting in low vibration reduction efficiency for the connected structures. Summary of the Invention

[0004] This invention provides a composite negative stiffness mechanical connection device and a multi-parameter determination method between structures. The device achieves negative stiffness connection between structures by using the preloaded springs in the preloaded negative stiffness upper arm and the preloaded negative stiffness lower arm and the relative deformation between the structures. Compared with other vibration control connection devices between structures, this device does not need to acquire the physical quantities of the vibration state of the structure in real time. It only needs to passively rely on the relative deformation of structure A and structure B to realize the negative stiffness characteristics of the connection device. It has the advantages of simple control method, easy implementation, and stable negative stiffness within a large deformation range.

[0005] The technical solution of this invention is:

[0006] According to a first aspect of the present invention, a composite negative stiffness mechanical connection device between structures is provided, comprising a first negative stiffness generating device, a second negative stiffness generating device, a force transmission device, a first connection device, and a second connection device.

[0007] The power transmission device has four branches, namely, the first and second branches in opposite directions, and the third and fourth branches in opposite directions; the first branch is connected to structure A25, the second branch is connected to structure B26, the third branch is connected to the first negative stiffness generating device, and the fourth branch is connected to the second negative stiffness generating device; the end of the first negative stiffness generating device away from the power transmission device is connected to structure A25 and structure B26 through the first connecting device, and the end of the second negative stiffness generating device away from the power transmission device is connected to structure A25 and structure B26 through the second connecting device.

[0008] The first negative stiffness generating device and the second negative stiffness generating device have the same structure, both including a pre-compression negative stiffness large arm 16 and a pre-compression negative stiffness small arm 17; the pre-compression negative stiffness small arm 17 has the same structure as the pre-compression negative stiffness large arm 16 but is smaller in size, the pre-compression negative stiffness large arm 16 is arranged along a first direction, and the pre-compression negative stiffness small arm 17 is arranged along a second direction and is detachably embedded in the receiving cavity of the pre-compression negative stiffness large arm 16.

[0009] Furthermore, the force transmission device includes a guide rod 4, a large metal slider 5, a force guide rod A6, a force transmission rod 7, a small metal slider 19, and a force guide rod B21;

[0010] The guide rod 4 passes through the large metal slider 5, and one end of the guide rod 4 serves as the first branch. Two force transmission rods 7 are parallel to the guide rod 4 and symmetrically arranged on both sides of the guide rod 4. One end of the two force transmission rods 7 is connected to the large metal slider 5 by a ball joint 12, and the other end of the two force transmission rods 7 and the other end of the guide rod 4 serve as the second branch.

[0011] The large metal slider 5 is perpendicular to the first branch on both sides, forming the third and fourth branches. The third and fourth branches have the same structural arrangement, each equipped with a guide rod A6, a small metal slider 19, and a guide rod B21. The guide rod A6 passes through the small metal slider 19 located in the pre-compression negative stiffness arm 16, and one end of the guide rod A6 is connected to the large metal slider 5 via a rotating hinge 11, while the other end of the guide rod A6 is connected to the pre-compression negative stiffness arm 16. One end of the guide rod B21 is connected to the end of the small metal slider 19 via a rotating hinge 11, while the other end of the guide rod B21 is connected to the pre-compression negative stiffness arm 17.

[0012] Furthermore, both the preloaded negative stiffness upper arm 16 and the preloaded negative stiffness lower arm 17 include a preloaded spring 1, a guide sleeve 2, and a guide slip 3. The two ends of the preloaded spring 1 are end capped with steel plates. One end of the guide sleeve 2 is connected to the end cap of one end of the preloaded spring 1, and the other end of the guide sleeve 2 is open. The inner wall of the guide sleeve 2 is provided with a guide groove along the length of the sleeve. One end of the guide slip 3 is connected to the preloaded spring 1, and the other end of the guide slip 3 is located in the guide groove and can slide freely along the guide groove.

[0013] In the preloaded negative stiffness boom 16, one end cap of the preloaded spring 1 is connected to the lateral reaction plate 8 in the auxiliary device through a rotating hinge 11, and the other end cap is fixed to one end of the guide rod A6;

[0014] In the pre-compression negative stiffness arm 17, one end cap of the pre-compression spring 1 is connected to the inner wall of the guide sleeve 2 in the pre-compression negative stiffness arm 16 through a rotating hinge 11, and the other end cap is fixed to one end of the guide rod B21.

[0015] Furthermore, the guide rod A6 is provided with an annular plate 20, and the annular plate 20 is provided with a permanent magnet 24, so that the annular plate 20 and the small metal slider 19 have a first state of adsorption and a second state of separation.

[0016] Furthermore, the permanent magnet sheets 24 are arranged in a ring array around the outer periphery of the guide rod A6.

[0017] Furthermore, the pre-compression negative stiffness arm 16 is provided with a limiting plate 18 to limit the movement of the small metal slider 19 along the axial direction of the guide rod A6; and the limiting plate 18 in the first negative stiffness generating device and the limiting plate 18 in the second negative stiffness generating device are arranged on the side of the two pre-compression negative stiffness arms 17 that are far apart.

[0018] According to a second aspect of the present invention, a method for determining multiple parameters of a composite negative stiffness mechanical connection device between structures is provided, comprising:

[0019] S1. Determine the negative stiffness required for the composite negative stiffness mechanical connection device between structures A25 and B26, denoted as k. d ;

[0020] S2. Determine the constant length of the preloaded negative stiffness boom, denoted as L;

[0021] S3. Based on the mechanism of negative stiffness generation of the preloaded negative stiffness boom, list the constraint equations;

[0022] S4. Based on the constraint equation, determine several combinations of K and Δ in the preloaded negative stiffness boom, and select one combination of K and Δ as the parameter of the preloaded spring 1 in the preloaded negative stiffness boom; where Δ is the pre-compression amount of the preloaded spring 1 in the preloaded negative stiffness boom; K is the stiffness coefficient of the preloaded spring 1 in the preloaded negative stiffness boom.

[0023] S5. The intersection of the preloaded negative stiffness boom force-displacement curve and the straight line with slope tanθ2 passing through the origin is denoted as (x). hj ,F 1hjFrom this intersection information, the initial distance between the annular plate 20 and the small metal slider 19 is obtained, which is called the starting length l0 of the preloaded negative stiffness arm. Where tanθ2=k d ;

[0024] S6. Determine the constant length L of the preloaded negative stiffness arm. x ;

[0025] S7. The pre-compression amount of the pre-compression spring 1 in a pre-compression negative stiffness forearm is initially given as Δ. x ;

[0026] S8, Calculate in x hj ~x h0 Within the range of required stiffness k d The difference F between the determined output force and the output force of the boom under preload negative stiffness. Δ ; where x h0 The horizontal coordinate of the intersection point of the preloaded negative stiffness boom force-displacement curve and the straight line with slope tanθ1 passing through the origin is indicated; tanθ1 is the tangent of the line connecting the origin and the point of maximum output in the preloaded negative stiffness boom force-displacement curve, and is called the secant stiffness.

[0027] S9. Establish the horizontal output expression of the preloaded negative stiffness arm. Based on the data in S8, the horizontal output expression of the preloaded negative stiffness arm is the expression to be fitted, and parameter K1 is the parameter to be fitted. The value of the stiffness coefficient K1 of the preloaded negative stiffness arm is obtained by using the nonlinear least squares method.

[0028] S10. Determine the Δ given in S7 and K1 derived from S9. x Adaptability level: When the adaptation level is reached, the design is completed.

[0029] The beneficial effects of this invention are:

[0030] The negative stiffness mechanical connection device provided by this invention generates the required negative stiffness effect. On the one hand, it enables the connected structures to perform tuned vibration reduction during vibration, thereby transforming the vibration between the connected structures into mutual vibration reduction and control. On the other hand, it gives the connected structures better energy dissipation capabilities. Furthermore, structures connected using the negative stiffness connection device have advantages such as wide vibration reduction bandwidth and low amplitude-frequency peak value, and can be widely used in connected adjacent structures, mega-substructures, structures with added rocker walls, and structures with outer or inner reinforcement. The parameter determination method mainly involves first determining the required negative stiffness of the connection between the structures, then determining the constant length of the preloaded negative stiffness arm based on actual conditions, then determining the stiffness and precompression of the preloaded spring inside the preloaded negative stiffness arm using constraint equations, and finally determining the relevant parameters of the preloaded negative stiffness arm based on the parameters of the preloaded negative stiffness arm, thus completing the determination of the relevant parameters of the device. Attached Figure Description

[0031] Figure 1 This is a top view of the composite negative stiffness mechanical connection device between the structures of the present invention;

[0032] Figure 2 yes Figure 1 AA section – internal section of the guide sleeve;

[0033] Figure 3 This is a top view of the rotating hinge.

[0034] Figure 4 This is a front elevation view of the lateral reaction plate and the lateral enclosure plate;

[0035] Figure 5 This is the mechanism by which negative stiffness occurs when a preloaded spring starts.

[0036] Figure 6 This is a detailed diagram showing the positions of the annular plate and the permanent magnet sheet;

[0037] Figure 7 This is a diagram illustrating the process of obtaining the parameters for the preloaded negative stiffness boom.

[0038] Figure 8 After obtaining l0 and F Δ The illustration;

[0039] Figure 9 This is a diagram illustrating the process of obtaining the preloaded negative stiffness arm parameters Δx and K1.

[0040] Figure 10 This is a diagram illustrating the combined force output of the preloaded negative stiffness upper arm and the preloaded negative stiffness lower arm;

[0041] The labels in the diagram are as follows: 1-Preload spring, 2-Guide sleeve, 3-Guide slide, 4-Guide rod, 5-Large metal slider, 6-Guide rod A, 7-Force transmission rod, 8-Side reaction plate, 9-Side enclosure plate, 10-End face connecting plate, 11-Rotating hinge, 12-Spherical hinge, 13-Rotating shaft, 14-Bearing, 15-Connecting piece, 16-Preload negative stiffness upper arm, 17-Preload negative stiffness lower arm, 18-Limiting plate, 19-Small metal slider, 20-Annular plate, 21-Guide rod B, 22-Anchor bolt, 23-Support rod, 24-Permanent magnet, 25-Structure A, 26-Structure B. Detailed Implementation

[0042] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention. It should be noted that, unless otherwise specified, the embodiments and features in the embodiments of this application can be arbitrarily combined with each other.

[0043] Example 1: As Figures 1-10 As shown, according to a first aspect of the present invention, a composite negative stiffness mechanical connection device between structures is provided, including a first negative stiffness generating device, a second negative stiffness generating device, a force transmission device, a first connecting device, and a second connecting device; the force transmission device has four branches, with the first and second branches being opposite each other, and the third and fourth branches being opposite each other; the first branch is connected to structure A25, the second branch is connected to structure B26, the third branch is connected to the first negative stiffness generating device, and the fourth branch is connected to the second negative stiffness generating device; the end of the first negative stiffness generating device away from the force transmission device is connected to structure A25 via the first connecting device. Structure B26 is connected, and the end of the second negative stiffness generating device away from the power transmission device is connected to structure A25 and structure B26 through a second connecting device; the first negative stiffness generating device and the second negative stiffness generating device have the same structure, both including a pre-compression negative stiffness large arm 16 and a pre-compression negative stiffness small arm 17; the pre-compression negative stiffness small arm 17 has the same structure as the pre-compression negative stiffness large arm 16 but is smaller in size, the pre-compression negative stiffness large arm 16 is arranged along a first direction, and the pre-compression negative stiffness small arm 17 is arranged along a second direction and is detachably embedded in the receiving cavity of the pre-compression negative stiffness large arm 16, the second direction being perpendicular to the first direction.

[0044] Further, the force transmission device includes a guide rod 4, a large metal slider 5, a force guide rod A6, a force transmission rod 7, a small metal slider 19, and a force guide rod B21; the guide rod 4 passes through the large metal slider 5, and one end of the guide rod 4 serves as a first branch (the guide rod 4 enters the structure A25 through a round hole and is anchored to the structure A25); two force transmission rods 7 are parallel to the guide rod 4 and symmetrically arranged on both sides of the guide rod 4; one end of the two force transmission rods 7 is connected to the large metal slider 5 by a ball joint 12; the other end of the two force transmission rods 7 and the other end of the guide rod 4 serve as a second branch (the other end of the two force transmission rods 7 is connected to the end face connecting plate 10 by a ball joint 12 and connected to the structure B21 via an anchor bolt 22 through the end face connecting plate 10). 6. The other end of the guide rod 4 extends into a pre-made hole in structure B26 that can slide freely along the axial direction of the guide rod 4; the large metal slider 5 is perpendicular to the first branch on both sides, forming the third and fourth branches; the third and fourth branches have the same structural arrangement, each equipped with a guide rod A6, a small metal slider 19, and a guide rod B21; the guide rod A6 passes through the small metal slider 19 located in the pre-compression negative stiffness arm 16, and one end of the guide rod A6 is connected to the large metal slider 5 through a rotating hinge 11, while the other end of the guide rod A6 is connected to the pre-compression negative stiffness arm 16; one end of the guide rod B21 is connected to the end of the small metal slider 19 through a rotating hinge 11, while the other end of the guide rod B21 is connected to the pre-compression negative stiffness arm 17.

[0045] For example, with respect to the rotational hinge 11, refer to Figure 3 The guide rod A6 shown is connected to the large metal slider 5 at one end via a rotating hinge 11. Specifically, the rotating shaft 13 of the rotating hinge 11 is connected to the large metal slider 5 via a connector 15, and the rotating shaft 13 is connected to the guide rod A6 via a bearing 14.

[0046] Furthermore, the large metal slider 5 is a cuboid or cube. Taking a cuboid as an example, four of its six faces are rectangles, and two are squares. One square face of the large metal slider is connected to the force transmission rod 7 via a ball joint 12. A circular hole is opened at the centroid of the square face of the large metal slider 5, through which the guide rod 4 passes, allowing the large metal slider 5 to slide along the length of the guide rod 4. The two opposite rectangular faces of the large metal slider 5 are connected to the force transmission rod A6 via rotating hinges 11. The small metal slider 19 is also a cuboid or cube.

[0047] Furthermore, both the pre-compression negative stiffness upper arm 16 and the pre-compression negative stiffness lower arm 17 include a pre-compression spring 1, a guide sleeve 2, and a guide slip 3. The two ends of the pre-compression spring 1 are end capped with steel plates. One end of the guide sleeve 2 is connected to the end cap of one end of the pre-compression spring 1, and the other end of the guide sleeve 2 is open (for the guide rod A6 and guide rod B21 to enter and exit). The inner wall of the guide sleeve 2 is provided with a guide groove along the length of the sleeve. One end of the guide slip 3 is connected to the pre-compression spring 1, and the other end of the guide slip 3 is located in the guide groove and can slide freely along the guide groove.

[0048] Furthermore, in the preloaded negative stiffness boom 16, one end cap of the preloaded spring 1 is connected to the lateral reaction plate 8 in the auxiliary device through a rotating hinge 11, and the other end cap is fixed to one end of the guide rod A6;

[0049] Furthermore, in the preloaded negative stiffness arm 17, one end cap of the preloaded spring 1 is connected to the inner wall of the guide sleeve 2 in the preloaded negative stiffness arm 16 via a rotating hinge 11, and the other end cap is fixed to one end of the guide rod B21.

[0050] refer to Figure 2 The guide sleeve 2 has a groove-shaped cross-section, and one guide groove is provided on the bottom surface and one on each of the two sides of the guide sleeve 2, for a total of three guide grooves.

[0051] Furthermore, the first and second connecting devices have the same structure, both including a lateral reaction plate 8 and a lateral enclosure plate 9 arranged in parallel and partially overlapping manner; one end of the lateral reaction plate 8 is connected to structure A25 through an end face connecting plate 10, and the other end of the lateral reaction plate 8 and one end of the lateral enclosure plate 9 are arranged in overlapping manner; a support rod 23 is installed on the outer side of the lateral reaction plate 8, and the inner side of the lateral reaction plate 8 is connected to one end cap of the preload spring 1 in the preload negative stiffness arm through a rotating hinge 11; the other end of the lateral enclosure plate 9 is connected to structure B26 through an end face connecting plate 10, and one end of the lateral enclosure plate 9 has a slot so that the horizontal sliding of the lateral enclosure plate 9 is not obstructed by the support rod 23 installed on the outer side of the lateral reaction plate 8.

[0052] Furthermore, the guide rod A6 is provided with an annular plate 20, and the annular plate 20 is provided with permanent magnets 24, so that the annular plate 20 and the small metal slider 19 have a first state of adsorption and a second state of separation. Multiple permanent magnets 24 are arranged in a ring array around the outer periphery of the guide rod A6.

[0053] Furthermore, the pre-compression negative stiffness arm 16 is provided with a limiting plate 18 to limit the movement of the small metal slider 19 along the axial direction of the guide rod A6; and the limiting plate 18 in the first negative stiffness generating device and the limiting plate 18 in the second negative stiffness generating device are arranged on the side of the two pre-compression negative stiffness arms 17 that are far apart.

[0054] For example, such as Figure 1 As shown, two spaced limiting plates 18 are installed in the guide sleeve 2 of the pre-compression negative stiffness arm 16 of the second negative stiffness generating device. One end of the limiting plate 18 is connected to the guide sleeve 2 of the pre-compression negative stiffness arm 16, and the other end of the limiting plate 18 is a free end.

[0055] The negative stiffness generation mechanism of the composite negative stiffness mechanical connection device between structures provided by the present invention is explained below:

[0056] Structures A25 and B26 from Figure 1 When the initial state shown shows horizontal relative deformation that has not reached the preset threshold, the force transmission rod 7 drives the large metal slider 5 to produce horizontal displacement, which in turn causes the preload spring 1 to generate a thrust on the large metal slider 5 through the guide rod A6. The vertical components of this thrust are balanced, and the horizontal component acts on the floor of structure B26 through the force transmission rod 7. The reaction force of this horizontal component is transmitted to the floor of structure A25 through the lateral reaction plate 8 and the support rod 23. At this time, the horizontal component generated by the preload negative stiffness arm 16 is the negative stiffness force between structure A25 and structure B26.

[0057] When the horizontal relative deformation between structure A25 and structure B26 reaches a preset threshold, the annular plate 20 contacts the small metal slider 19 and is attracted by the permanent magnet 24. When the horizontal relative deformation between structure A25 and structure B26 exceeds the preset threshold, the small metal slider 19 slides along the axial direction of the guide rod A6, thereby activating the pre-compression negative stiffness arm 17. After the pre-compression negative stiffness arm 17 is activated, the thrust generated by the pre-compression spring in the pre-compression negative stiffness arm is transmitted to the small metal slider 19 by the guide rod B21. The component of the thrust transmitted to the small metal slider 19 along the axial direction of the guide rod A6 is transmitted to the large metal slider 5, becoming a thrust on the large metal slider 5. The horizontal component of this thrust becomes part of the negative stiffness force between structure A25 and structure B26. At this time, the negative stiffness force between structure A25 and structure B26 is composed of the combined output forces of the pre-compression negative stiffness large arm 16 and the pre-compression negative stiffness arm 17.

[0058] As the horizontal relative deformation of structures A25 and B26 changes from exceeding a preset threshold range to falling below a preset threshold, the limiting plate 18 stops the small metal slider 19, thereby separating the annular plate 20 from the small metal slider 19. The pre-compressed negative stiffness upper arm and the pre-compressed negative stiffness lower arm no longer exert force together. At this point, only the force exerted by the pre-compressed negative stiffness upper arm serves as the negative stiffness force between structures A25 and B26.

[0059] The negative stiffness characteristic of this connecting device is mainly manifested as follows: when structure A25 and structure B26 are far apart, they generate mutual thrust; while when they are close together, they generate mutual tension.

[0060] When structure A25 and structure B26 undergo relative horizontal deformation not exceeding a preset threshold, the negative stiffness of the connecting device is obtained based on the relationship between the output force of the preloaded negative stiffness upper arm 16 and the relative horizontal deformation of structure A25 and structure B26; when structure A25 and structure B26 undergo relative horizontal deformation exceeding a preset threshold, the negative stiffness of the connecting device is obtained based on the relationship between the combined output force of the preloaded negative stiffness upper arm 16 and the preloaded negative stiffness lower arm 17 and the relative horizontal deformation of structure A25 and structure B26.

[0061] According to a second aspect of the present invention, a method for determining the parameters of a composite negative stiffness mechanical connection device between structures is provided, comprising:

[0062] S1. Determine the negative stiffness required for the connection device between structure A and structure B26, denoted as k. d .

[0063] S2. Based on the actual spatial conditions of structure A and structure B26, determine the constant length of the preloaded negative stiffness arm, denoted as L (equal to the sum of the compressed length of the preloaded spring 1 inside the preloaded negative stiffness arm and the length of the guide rod A).

[0064] S3. Based on the mechanism of negative stiffness generation of the preloaded negative stiffness boom, the following set of equations (1) to (7) are listed:

[0065] θ1+θ3=2θ2 (1)

[0066]

[0067] tanθ2=k d (4)

[0068]

[0069] C1=Δ+L (7)

[0070] Wherein, tanθ1 is the tangent of the line connecting the origin and the point of maximum output in the force-displacement curve of the preloaded negative stiffness boom, called the secant stiffness; tanθ3 is the initial stiffness of the force-displacement curve of the preloaded negative stiffness boom; x h0 This represents the horizontal coordinate of the intersection point of the force-displacement curve of the preloaded negative stiffness boom and the straight line with slope tanθ1 passing through the origin; F 1h (x h0) represents the maximum output force of the preloaded negative stiffness boom; Δ represents the pre-compression of the preloaded spring 1 in the preloaded negative stiffness boom; K represents the stiffness coefficient of the preloaded spring 1 in the preloaded negative stiffness boom; L represents the constant length of the preloaded negative stiffness boom, which is equal to the compressed length of the preloaded spring 1 plus the length of the guide rod A6. tanθ2 represents the negative stiffness required for the connection device between structure A and structure B26;

[0071] S4. Using equation set (1) to (7) as constraint equations, determine several combinations of K and Δ in the preloaded negative stiffness boom. Based on actual conditions, select one combination of K and Δ as the parameter of the preloaded spring 1 in the preloaded negative stiffness boom.

[0072] S5. From the following two equations (8) and (9), the intersection point of the preloaded negative stiffness boom force-displacement curve and the straight line with a slope of tanθ2 passing through the origin is obtained. This intersection point is denoted as (x hj ,F 1hj From this intersection information, the initial distance between the annular plate 20 and the small metal slider 19 is obtained, which is called the starting length l0 of the preloaded negative stiffness arm.

[0073] F 1h =tanθ2x h (8)

[0074]

[0075] Where, x h The horizontal coordinates of the large metal slider 5 relative to its original position (the large metal slider 5 is in Figure 1 The position at that time can be considered the original position), F 1h For the large metal slider 5 in x h At the location, the negative stiffness force is generated by the preloaded negative stiffness boom.

[0076] S6. Determine the constant length L of the preloaded negative stiffness arm based on the actual situation. x It is equal to the sum of the compressed length of the preloaded spring 1 in the preloaded negative stiffness forearm and the length of the guide rod B.

[0077] S7. The pre-compression amount of the pre-compression spring 1 in a pre-compression negative stiffness forearm is initially given as Δ. x .

[0078] S8, according to the following formula (10), the value of x is obtained. hj ~x h0 Within the range of required stiffness k d The difference F between the determined output force and the output force of the boom under preload negative stiffness. Δ .

[0079]

[0080] In the formula, x h0 The horizontal coordinate represents the intersection of the preloaded negative stiffness boom force-displacement curve and the straight line with slope tanθ1 passing through the origin.

[0081] S9. The horizontal output of the preloaded negative stiffness arm is written as shown in the following formula (11). Based on the data of formula (10), formula (11) is the expression to be fitted, and parameter K1 is the parameter to be fitted. The value of the stiffness coefficient K1 of the preloaded negative stiffness arm is obtained by nonlinear least squares method.

[0082]

[0083] In the formula, f 1h The horizontal output force of the preloaded negative stiffness forearm is represented by x0; x0 is the coordinate of the small metal slider sliding along the axis of the guide rod A; C2 = Δ x +L x .

[0084] S10. Determine the Δ given in S7 and K1 derived from S9. x The degree of fit. If it fits, the design ends; if it doesn't fit, readjust Δ in S7. x After obtaining the value, repeat S8 to S10 until the final design is completed.

[0085] From S1 to S10 above, the required negative stiffness k between structure A and structure B26 can be determined. d The relevant design parameters K, Δ, and L of the preloaded negative stiffness boom and the relevant design parameters K1 and Δ of the preloaded negative stiffness forearm are obtained. x L x The negative stiffness force F of the negative stiffness device n Determined by the following formula (12), where,

[0086]

[0087] For example: When the required negative stiffness of structures A25 and B26 in a main-attached structure is -0.0823 kN / mm, and within the allowable space of structures A25 and B26, the constant length L of the preload negative stiffness arm is 260 mm, where the compressed length of the preload spring 1 is 150 mm, and the length of the guide rod A6 is 110 mm, then according to S3 to S10, the parameters of the connection device between structures A25 and B26 are as follows:

[0088] The stiffness coefficient K of the preloaded negative stiffness boom spring is 0.043 kN / mm;

[0089] The pre-compression amount of the pre-stressed negative stiffness boom spring is Δ = 317 mm;

[0090] The starting length l0 of the preloaded negative stiffness forearm is 34.8 mm.

[0091] The stiffness coefficient K1 of the preloaded negative stiffness forearm spring is 0.0438 kN / mm.

[0092] Precompression amount Δ of preloaded negative stiffness forearm spring x =128.5mm

[0093] The final result is as follows Figures 7-10 As shown.

[0094] The specific embodiments of the present invention have been described in detail above with reference to the accompanying drawings. However, the present invention is not limited to the above embodiments. Within the scope of knowledge possessed by those skilled in the art, various changes can be made without departing from the spirit of the present invention.

Claims

1. A composite negative stiffness mechanical connection device between structures, characterized in that, It includes a first negative stiffness generating device, a second negative stiffness generating device, a force transmission device, a first connecting device, and a second connecting device; The power transmission device has four branches, namely the first and second branches in opposite directions, and the third and fourth branches in opposite directions; the first branch is connected to structure A (25), the second branch is connected to structure B (26), the third branch is connected to the first negative stiffness generating device, and the fourth branch is connected to the second negative stiffness generating device. The first negative stiffness generating device is connected to structure A (25) and structure B (26) at the end furthest from the power transmission device via the first connecting device, and the second negative stiffness generating device is connected to structure A (25) and structure B (26) at the end furthest from the power transmission device via the second connecting device. The first negative stiffness generating device and the second negative stiffness generating device have the same structure, both including a pre-compression negative stiffness large arm (16) and a pre-compression negative stiffness small arm (17); the pre-compression negative stiffness small arm (17) has the same structure as the pre-compression negative stiffness large arm (16) but is smaller in size. The pre-compression negative stiffness large arm (16) is arranged along a first direction, and the pre-compression negative stiffness small arm (17) is arranged along a second direction and is detachably embedded in the receiving cavity of the pre-compression negative stiffness large arm (16).

2. The composite negative stiffness mechanical connection device between structures according to claim 1, characterized in that, The force transmission device includes a guide rod (4), a large metal slider (5), a force guide rod A (6), a force transmission rod (7), a small metal slider (19), and a force guide rod B (21); The guide rod (4) passes through the large metal slider (5), and one end of the guide rod (4) serves as the first branch. Two force transmission rods (7) are parallel to the guide rod (4) and symmetrically arranged on both sides of the guide rod (4). One end of the two force transmission rods (7) is connected to the large metal slider (5) by a ball joint (12), and the other end of the two force transmission rods (7) and the other end of the guide rod (4) serve as the second branch. The large metal slider (5) is perpendicular to the first branch on both sides, forming the third and fourth branches. The third and fourth branches have the same structure and are equipped with a guide rod A (6), a small metal slider (19), and a guide rod B (21). The guide rod A (6) passes through the small metal slider (19) located in the pre-compression negative stiffness arm (16), and one end of the guide rod A (6) is connected to the large metal slider (5) through a rotating hinge (11), while the other end of the guide rod A (6) is connected to the pre-compression negative stiffness arm (16). One end of the guide rod B (21) is connected to the end of the small metal slider (19) through a rotating hinge (11), while the other end of the guide rod B (21) is connected to the pre-compression negative stiffness arm (17).

3. The composite negative stiffness mechanical connection device between structures according to claim 1, characterized in that, The pre-compression negative stiffness upper arm (16) and the pre-compression negative stiffness lower arm (17) both include a pre-compression spring (1), a guide sleeve (2), and a guide slip (3). The two ends of the pre-compression spring (1) are end capped with steel plates. One end of the guide sleeve (2) is connected to the end cap of one end of the pre-compression spring (1). The other end of the guide sleeve (2) is open. The inner wall of the guide sleeve (2) is provided with a guide groove along the length of the sleeve. One end of the guide slip (3) is connected to the pre-compression spring (1). The other end of the guide slip (3) is located in the guide groove and can slide freely along the guide groove. In the preloaded negative stiffness boom (16), one end cap of the preloaded spring (1) is connected to the lateral reaction plate (8) in the auxiliary device through a rotating hinge (11), and the other end cap is fixed to one end of the guide rod A (6); In the pre-compression negative stiffness arm (17), one end cap of the pre-compression spring (1) is connected to the inner wall of the guide sleeve (2) in the pre-compression negative stiffness arm (16) through a rotating hinge (11), and the other end cap is fixed to one end of the guide rod B (21).

4. The composite negative stiffness mechanical connection device between structures according to claim 1, characterized in that, The guide rod A (6) is provided with an annular plate (20), and the annular plate (20) is provided with a permanent magnet (24), so that the annular plate (20) and the small metal slider (19) have a first state of adsorption and a second state of separation.

5. The composite negative stiffness mechanical connection device between structures according to claim 4, characterized in that, The permanent magnet sheet (24) is arranged in a ring array around the outer periphery of the guide rod A (6).

6. The composite negative stiffness mechanical connection device between structures according to claim 1, characterized in that, The pre-compression negative stiffness arm (16) is provided with a limiting plate (18) to limit the movement of the small metal slider (19) along the axial direction of the guide rod A (6); and the limiting plate (18) in the first negative stiffness generating device and the limiting plate (18) in the second negative stiffness generating device are arranged on the side of the two pre-compression negative stiffness arms (17) that are far apart.

7. A method for determining multiple parameters of a composite negative stiffness mechanical connection device between structures, characterized in that, include: S1. Determine the negative stiffness required for the composite negative stiffness mechanical connection device between structures A(25) and B(26), denoted as k. d ; S2. Determine the constant length of the preloaded negative stiffness boom, denoted as L; S3. Based on the mechanism of negative stiffness generation of the preloaded negative stiffness boom, list the constraint equations; S4. Based on the constraint equation, determine several combinations of K and Δ in the preloaded negative stiffness boom, and select one combination of K and Δ as the parameter of the preloaded spring (1) in the preloaded negative stiffness boom; where Δ is the pre-compression amount of the preloaded spring (1) in the preloaded negative stiffness boom; K is the stiffness coefficient of the preloaded spring (1) in the preloaded negative stiffness boom. S5. The intersection of the preloaded negative stiffness boom force-displacement curve and the straight line with slope tanθ2 passing through the origin is denoted as (x). hj ,F 1hj From this intersection information, the initial distance between the annular plate (20) and the small metal slider (19) is obtained, which is called the starting length l0 of the preloaded negative stiffness arm. Where tanθ2=k d ; S6. Determine the constant length L of the preloaded negative stiffness arm. x ; S7. The pre-compression amount of the pre-compression spring (1) in a pre-compression negative stiffness forearm is initially given as Δ. x ; S8, Calculate in x hj ~x h0 Within the range of required stiffness k d The difference F between the determined output force and the output force of the boom under preload negative stiffness. Δ ;where x h0 The horizontal coordinate of the intersection point of the preloaded negative stiffness boom force-displacement curve and the straight line with slope tanθ1 passing through the origin is indicated; tanθ1 is the tangent of the line connecting the origin and the point of maximum output in the preloaded negative stiffness boom force-displacement curve, and is called the secant stiffness. S9. Establish the horizontal output expression of the preloaded negative stiffness arm. Based on the data in S8, the horizontal output expression of the preloaded negative stiffness arm is the expression to be fitted, and parameter K1 is the parameter to be fitted. The value of the stiffness coefficient K1 of the preloaded negative stiffness arm is obtained by using the nonlinear least squares method. S10. Determine the Δ given in S7 and K1 derived from S9. x Adaptability level: When the adaptation level is reached, the design is completed.

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