Vibration isolator based on metamaterial with adjustable rigidity and Poisson ratio

Abstract

The invention discloses a vibration isolator based on a metamaterial with adjustable rigidity and Poisson's ratio. The vibration isolator is formed by arranging a plurality of metamaterial structure units with adjustable rigidity and Poisson's ratio in an array. The metamaterial structure unit with adjustable rigidity and Poisson's ratio is composed of a positive Poisson's ratio unit (1), a negative Poisson's ratio unit (2), a first bilateral supporting unit (3), a second bilateral supporting unit (4), a first electromagnet (5) and a second electromagnet (6). The difference between the positive Poisson's ratio units (1) and the negative Poisson's ratio units (2) is that upper and lower support arms on the same side are arranged in a convex or concave manner. The first double-side supporting unit (3) and the second double-side supporting unit (4) are the same in structure, and the installation positions of the first double-side supporting unit (3) and the second double-side supporting unit (4) in the adjustable rigidity and Poisson ratio metamaterial structure unit are the same. When the vibration isolator is in a full-locking state, the structural rigidity is the highest, and when the vibration isolator is in a full-free state, the structural rigidity is the lowest. And the structural rigidity is similar in a positive or negative poisson ratio state. Therefore, the ratio of the units in the locked state in the vibration isolator determines the structural rigidity characteristic of the vibration isolator.

Description

Technical Field

[0001] The present invention relates to a vibration isolator, and more particularly to a vibration isolator based on a metamaterial with adjustable stiffness and Poisson's ratio. Background Art

[0002] Metamaterials are listed as one of the top ten insights of the first decade of this century by Science magazine. Different from traditional materials, metamaterials are constructed based on the design of the internal structure of the material. The concept of metamaterials first appeared in the field of electromagnetic materials. Since then, based on different construction principles and structural designs, metamaterials have derived extraordinary functions in different fields such as optics, acoustics, and mechanics. Their special properties also make them new materials in the fields of medicine, acoustics, wearable electronic devices, soft robots, etc. Therefore, in today's rapidly changing science and technology, the research on metamaterials has attracted much attention both internationally and domestically.

[0003] The extraordinary mechanical properties of mechanical metamaterials are mainly achieved through the design of microstructure configuration and its arrangement. After being manufactured, general mechanical metamaterials cannot change their own mechanical properties. However, with the help of some special materials or structures, the mechanical properties of mechanical metamaterials can be programmably controlled, including the adjustable properties of stiffness and Poisson's ratio.

[0004] Vibration isolators are elastic elements that connect equipment and foundations, used to reduce and eliminate vibration forces transmitted from equipment to foundations and vibrations transmitted from foundations to equipment. Currently, vibration isolators installed on the bottom plate frames of ships are mostly made of rubber. Rubber vibration isolators can be used in compression or shear. They have a large internal damping effect, are prone to aging, and have large creep under heavy loads. They are mainly used for high-frequency vibration isolation. However, the vibration frequency of ship auxiliary engines is not high and they are heavy. Rubber vibration isolators have certain limitations in the vibration isolation of ship auxiliary engines. Summary of the invention

[0005] Stiffness and Poisson's ratio are essentially the deformation characteristics of the reaction material. In order to realize the adjustability of the stiffness and Poisson's ratio of the metamaterial, the present invention designs a Poisson's ratio structure acting on the vibration isolator, that is, a vibration isolator based on the adjustable stiffness and Poisson's ratio metamaterial. The configuration of the Poisson's ratio structure is as follows: Figure 1 As shown, according to the characteristics of negative Poisson's ratio metamaterials, there are various structures of array arrangement, such as Figure 1 The classic positive and negative Poisson's ratio structures shown are combined, and the stiffness of different units is adjusted separately to achieve the stiffening of different units, so that the positive or negative Poisson's ratio characteristics of the isolator can be achieved, while the overall stiffness can also be regulated. This provides a new design idea for metamaterials with adjustable stiffness and Poisson's ratio to become isolators.

[0006] The present invention discloses an isolator based on an adjustable stiffness and Poisson's ratio metamaterial. The isolator is composed of a plurality of adjustable stiffness and Poisson's ratio metamaterial structural units arranged in an array. In order to achieve balanced upper and lower forces on the isolator, an upper force-bearing member (7) and an upper matching plate (70) are provided at the upper part of the isolator, and a lower force-bearing member (8) and a lower matching plate (80) are provided at the lower part of the isolator. The upper force-bearing member (7) and the lower force-bearing member (8) are used in conjunction with the adjustable stiffness and Poisson's ratio metamaterial structural unit. The adjustable stiffness and Poisson's ratio metamaterial structural unit is composed of a positive Poisson's ratio unit (1), a negative Poisson's ratio unit (2), a first bilateral support unit (3), a second bilateral support unit (4), a first electromagnet (5) and a second electromagnet (6).

[0007] The difference between the positive Poisson's ratio unit (1) and the negative Poisson's ratio unit (2) lies in the convex or concave arrangement of the upper and lower arms on the same side.

[0008] The first bilateral support unit (3) and the second bilateral support unit (4) have the same structure, and are installed at the same position in the adjustable stiffness and Poisson's ratio metamaterial structure unit.

[0009] The positive Poisson's ratio unit (1) is provided with an A upper connecting plate (1A), A right upper supporting arm (1B), A right lower supporting arm (1C), A lower connecting plate (1D), A left lower supporting arm (1E), A left upper supporting arm (1F), A right outer boss (1G) and A left outer boss (1H);

[0010] The upper arm (1B) on the right side of A and the lower arm (1C) on the right side of A are inclined outwards on the same side;

[0011] The left upper arm (1F) of A and the left lower arm (1E) of A are inclined outwards on the same side;

[0012] Wherein, the right outer boss (1G) of A is arranged outside the junction of the right upper support arm (1B) of A and the right lower support arm (1C) of A;

[0013] Wherein, the A left outer boss (1H) is arranged outside the junction of the A left upper arm (1F) and the A left lower arm (1E);

[0014] A connecting plate (1A) is placed in an open U-shaped groove of a bilateral support unit of a metamaterial structural unit with adjustable stiffness and Poisson's ratio;

[0015] A lower connecting plate (1D) is placed in the open U-shaped groove (3F) of the first bilateral supporting unit (3).

[0016] The negative Poisson's ratio unit (2) is provided with a B upper connecting plate (2A), a B right upper supporting arm (2B), a B right lower supporting arm (2C), a B lower connecting plate (2D), a B left lower supporting arm (2E), a B left upper supporting arm (2F), a B right outer boss (2G) and a B left outer boss (2H);

[0017] Wherein, the right upper arm (2B) of B and the right lower arm (2C) of B are inclined inwards on the same side;

[0018] The upper arm (2F) on the left side of B and the lower arm (2E) on the left side of B are inclined inwards on the same side;

[0019] Wherein, the right outer boss (2G) of B is arranged outside the junction of the right upper arm (2B) of B and the right lower arm (2C) of B;

[0020] Wherein, the B left outer boss (2H) is arranged outside the junction of the B left upper arm (2F) and the B left lower arm (2E);

[0021] The upper connecting plate (2A) of B is placed in the open U-shaped groove (3F) of the double-sided supporting unit (3) of A;

[0022] B The lower connecting plate (2D) is placed in the open U-shaped groove (4F) of the second bilateral supporting unit (4).

[0023] The first bilateral support unit (3) is provided with a CA arc-shaped clamping arm (3A), a CB arc-shaped clamping arm (3B), a C clamping upper plate (3D), a C clamping lower plate (3E), and a C magnet installation panel (3G); the upper part of the first bilateral support unit (3) is an upper opening formed by the CA arc-shaped clamping arm (3A) and the CB arc-shaped clamping arm (3B), the middle part of the first bilateral support unit (3) is a clamping middle part formed by the C clamping upper plate (3D) and the C clamping lower plate (3E), and the lower part of the first bilateral support unit (3) is the C magnet installation panel (3G);

[0024] A CA through hole (3A1) is provided on one end of the CA arc-shaped clamp arm (3A), a CB through hole (3B1) is provided on one end of the CB arc-shaped clamp arm (3B), and a C-opening through hole (3C) is provided between the CA arc-shaped clamp arm (3A) and the CB arc-shaped clamp arm (3B); the C-opening through hole (3C) is used to place the first electromagnet (5), and studs are placed in the CA through hole (3A1) and the CB through hole (3B1), and nuts are sleeved on the studs to fix the first electromagnet (5) to the upper opening of the first bilateral support unit (3);

[0025] Wherein, a C-opening U-shaped groove (3F) is provided between the C-clamping upper plate (3D) and the C-clamping lower plate (3E), and the C-opening U-shaped groove (3F) is used to place the A-lower connecting plate (1D) of the positive Poisson's ratio unit (1) and the upper connecting plate (2A) of the negative Poisson's ratio unit (2B);

[0026] A C countersunk cavity (3G1) is provided on the C magnet installation panel (3G), a C center through hole (3G2) is provided in the middle of the C countersunk cavity (3G1), and the C center through hole (3G2) is used for wiring; a B suction patch (6A) is installed in the C countersunk cavity (3G1) for generating a driving force with the second electromagnet (6) after power is turned on.

[0027] The second bilateral support unit (4) is provided with a DA arc-shaped clamping arm (4A), a DB arc-shaped clamping arm (4B), a D clamping upper plate (4D), a D clamping lower plate (4E), and a D magnet installation panel (4G); the upper part of the second bilateral support unit (4) is an upper opening formed by the DA arc-shaped clamping arm (4A) and the DB arc-shaped clamping arm (4B), the middle part of the second bilateral support unit (4) is a clamping middle part formed by the D clamping upper plate (4D) and the D clamping lower plate (4E), and the lower part of the second bilateral support unit (4) is the D magnet installation panel (4G);

[0028] A DA through hole (4A1) is provided on one end of the DA arc-shaped clamp arm (4A), a DB through hole (4B1) is provided on one end of the DB arc-shaped clamp arm (4B), and a D open through hole (4C) is provided between the DA arc-shaped clamp arm (4A) and the DB arc-shaped clamp arm (4B); the D open through hole (4C) is used to place the second electromagnet (6), and studs are placed in the DA through hole (4A1) and the DB through hole (4B1), and nuts are sleeved on the studs to fix the second electromagnet (6) to the upper opening of the second bilateral support unit (4);

[0029] Wherein, between the D clamping upper plate (3D) and the D clamping lower plate (4E) is a D open U-shaped groove (4F), and the D open U-shaped groove (4F) is used to place the B lower connecting plate (2D) of the negative Poisson's ratio unit (2) and the upper connecting plate of the positive Poisson's ratio unit of another adjustable stiffness and Poisson's ratio metamaterial structure unit;

[0030] A D countersunk head cavity (4G1) is provided on the D magnet installation panel (4G), a D center through hole (4G2) is provided in the middle of the D countersunk head cavity (4G1), and the D center through hole (4G2) is used for wiring; another suction patch is installed in the D countersunk head cavity (4G1).

[0031] The upper force-bearing member (7) is provided with a G clamping upper plate (7D), a G clamping lower plate (7E), and a G magnet installation panel (7G); the upper force-bearing member (7) is provided with a G clamping upper plate (7D), a G clamping lower plate (7E), and a G magnet installation panel (7G); between the G clamping upper plate (7D) and the G clamping lower plate (7E) is a G open U-shaped groove (7F), and the G open U-shaped groove (7F) is used to place the upper matching plate (70) and An upper connecting plate of a negative Poisson's ratio unit of a metamaterial structural unit with adjustable stiffness and Poisson's ratio; or an upper connecting plate of a positive Poisson's ratio unit of a metamaterial structural unit with adjustable stiffness and Poisson's ratio; a G countersunk head cavity (7G1) is provided on the G magnet mounting panel (7G), a G central through hole (7G2) is provided in the middle of the G countersunk head cavity (7G1), and the G central through hole (7G2) is used for wiring; and a suction patch is installed in the G countersunk head cavity (7G1).

[0032] The lower force-bearing member (8) is an integrally formed structural member; the lower force-bearing member (8) is provided with an HA arc-shaped clamping arm (8A), an HB arc-shaped clamping arm (8B), an H clamping upper plate (8D), and an H clamping lower plate (8E);

[0033] One end of the HA arc-shaped clamp arm (8A) is provided with a HA through hole (8A1), one end of the HB arc-shaped clamp arm (8B) is provided with a HB through hole (8B1), and an H open through hole (8C) is provided between the HA arc-shaped clamp arm (8A) and the HB arc-shaped clamp arm (8B); an electromagnet is placed in the H open through hole (8C), and studs are placed in the HA through hole (8A1) and the HB through hole (8B1), and nuts are sleeved on the studs to fix the electromagnet to the upper opening of the lower force-bearing member (8);

[0034] There is an H-open U-shaped groove (8F) between the H-clamping upper plate (3H) and the H-clamping lower plate (8E), and the H-open U-shaped groove (8F) is used to place a lower matching plate (80) and an upper connecting plate of a negative Poisson's ratio unit of an adjustable stiffness and Poisson's ratio metamaterial structural unit; or an upper connecting plate of a positive Poisson's ratio unit of an adjustable stiffness and Poisson's ratio metamaterial structural unit.

[0035] The advantages of the adjustable stiffness and Poisson's ratio metamaterial structural unit designed in the present invention are:

[0036] ① A mechanical metamaterial structure that can adjust the stiffness of the positive and negative Poisson's ratio units to achieve the overall structural stiffness and Poisson's ratio. It is an innovation and expansion of the existing adjustable mechanical performance metamaterial structure. It not only realizes the customized design of metamaterials with specific stiffness and Poisson's ratio, but also realizes the online adjustable characteristics of metamaterial stiffness and Poisson's ratio.

[0037] ② A two-dimensional metamaterial configuration based on the coupling of positive and negative Poisson's ratio units with adjustable stiffness was designed, and it was proposed to use electromagnetic control to achieve stiffness control of the positive and negative Poisson's ratio units.

[0038] ③Based on the proposed configuration, the stiffness and Poisson's ratio of the structure were theoretically analyzed, and the finite element simulation of the model was performed based on the Abaqus simulation software to verify the accuracy of the theoretical calculation and optimize the model.

[0039] ④The vibration isolator is composed of 5×5 grid-scale adjustable stiffness and Poisson’s ratio metamaterial structural units. Through loading experiments and parameter determination of stiffness and Poisson’s ratio, it is shown that the structure is compact and the vibration isolation effect is excellent. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] Figure 1 It is a structural diagram of a metamaterial structural unit with adjustable stiffness and Poisson's ratio designed by the present invention.

[0041] Figure 1A This is a structural diagram from another perspective of a metamaterial structural unit with adjustable stiffness and Poisson's ratio designed by the present invention.

[0042] Figure 1B yes Figure 1 Front view structure diagram of .

[0043] Figure 2 It is a decomposition diagram of a metamaterial structural unit with adjustable stiffness and Poisson's ratio designed by the present invention.

[0044] Figure 2A It is a schematic diagram of the structure and dimensions of the positive Poisson's ratio unit of the present invention.

[0045] Figure 2B It is a schematic diagram of the structure and dimensions of the negative Poisson's ratio unit of the present invention.

[0046] Figure 3 It is a structural diagram of the first bilateral support unit of the present invention.

[0047] Figure 4 It is a structural diagram of the second bilateral support unit of the present invention.

[0048] Figure 5 It is a front structural diagram of the vibration isolator based on the adjustable stiffness and Poisson's ratio metamaterial of the present invention.

[0049] Figure 5A This is another perspective structural diagram of the vibration isolator based on the adjustable stiffness and Poisson's ratio metamaterial of the present invention.

[0050] Figure 5B It is a structural diagram of the upper force-bearing member of the present invention.

[0051] Figure 5C This is a structural diagram of the upper force-bearing member from another perspective of the present invention.

[0052] Figure 5D It is a structural diagram of the lower force-bearing member of the present invention.

[0053] Figure 5E This is a structural diagram of the lower force-bearing member from another perspective of the present invention.

[0054] Figure 6 This is a diagram of the overall structural deformation of the vibration isolator of the present invention under a positive Poisson's ratio state.

[0055] Figure 7 This is a diagram of the overall structural deformation of the vibration isolator of the present invention under the negative Poisson's ratio state.

[0056] Figure 8 This is a diagram showing the overall structural deformation of the vibration isolator of the present invention in a free state.

[0057] Fig. 9 It is a simulation diagram of the overall structural deformation of the vibration isolator of the present invention under a negative Poisson's ratio state when the upper and lower boundaries bear the same pressure.

[0058] Fig.10 yes Fig. 9 Structural deformation curve of the negative Poisson's ratio state of the state isolator.

[0059] Fig.11 It is a simulation diagram of the overall structural deformation of the vibration isolator of the present invention under a positive Poisson's ratio state when the upper and lower boundaries bear the same pressure.

[0060] Fig.12 yes Fig.11 Structural deformation curve of the positive Poisson's ratio state of the state isolator.

[0061] Fig.13 It is a simulation diagram of the overall structural deformation of the vibration isolator of the present invention in a free state when the upper and lower boundaries bear the same pressure.

[0062] Fig.14 These are the displacement-load curves of the vibration isolator of the present invention under four conditions.

[0063] 1. Positive Poisson's ratio unit 1A.A Upper connecting plate 1A1.AA threaded hole 1B.A Right upper arm 1C.A Right lower arm 1D.A Lower connecting plate 1D1.AB threaded hole 1E.A Left lower arm 1F.A Left upper arm 1G.A Right outer boss 1H.A Left outer boss 2. Negative Poisson's ratio unit 2A.B upper connecting plate 2A1.BA threaded hole 2B.B Right upper arm 2C.B Right lower arm 2D.B Lower connecting plate 2D1.BB threaded hole 21E.B Left lower arm 2F.B Left upper arm 2G.B Right outer boss 2H.B Left outer boss 3. The first bilateral support unit 3A.CA arc clamp arm 3A1.CA through hole 3B.CB arc clamp arm 3B1.CB through hole 3C.C Opening through hole 3D.CA clamping upper plate 3E.CB clamping lower plate 3F.C Open U-shaped Cao 3G.C Magnet Mounting Panel 3G1.C countersunk cavity 3G2.C center through hole 4. Second bilateral support unit 4A.DA arc clamp arm 4A1.DA through hole 4B.DB curved clamp arm 4B1.DB through hole 4C.D Opening through hole 4D.DA clamping upper plate 4E.DB clamping lower plate 4F.C Open U-shaped Cao 4G.D connecting arm 4G1.D countersunk cavity 4G2.D center through hole 5. The first electromagnet 5A. First suction patch 6. Second electromagnet 6A. Second suction patch 7. Upper load bearing member 70. Flat panel 7D.GA clamping upper plate 7E.GB clamping lower plate 7F.G Open U-shaped Cao 7G.G Magnet Mounting Panel 7G1.G countersunk cavity 7G2.G center through hole 8. Lower load bearing member 80. Flat panel at the bottom 8A.HA arc clamp arm 8A1.HA Through Hole 8B.HB arc clamp arm 8B1.HB through hole 8C.H Open through hole 8D.HA clamping upper plate 8E.HB clamping lower plate 8F.H Open U-shaped Cao DETAILED DESCRIPTION

[0064] The present invention will be further described in detail below in conjunction with the accompanying drawings and embodiments. The various parameter demonstrations listed are only preferred embodiments of the present invention. It should be noted that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principles of the present invention, and these improvements and modifications should also be considered as the protection scope of the present invention.

[0065] See also Figure 1 , Figure 1A , Figure 1B , Figure 5 As shown, the present invention designs a vibration isolator based on adjustable stiffness and Poisson's ratio metamaterial, and the vibration isolator is composed of a plurality of adjustable stiffness and Poisson's ratio metamaterial structural units arranged in an array.

[0066] In the present invention, the adjustable stiffness and Poisson's ratio metamaterial structural unit is as follows Figure 1 , Figure 1A , Figure 1B As shown, it is composed of a positive Poisson's ratio unit 1, a negative Poisson's ratio unit 2, a first bilateral support unit 3, a second bilateral support unit 4, a first electromagnet 5 and a second electromagnet 6.

[0067] The difference between the positive Poisson's ratio unit 1 and the negative Poisson's ratio unit 2 lies in the convex or concave arrangement of the upper and lower arms on the same side.

[0068] The first bilateral support unit 3 and the second bilateral support unit 4 have the same structure and are installed at the same position in the adjustable stiffness and Poisson's ratio metamaterial structure unit. Figure 2 shown.

[0069] In the present invention, Figure 5 The vibration isolator shown is composed of 5×5 electromagnets. The 5 electromagnets are matched with 2 positive Poisson's ratio units and 3 negative Poisson's ratio units.

[0070] In the present invention, the driving force of the adjustable stiffness and Poisson's ratio metamaterial structural unit is controlled by an electromagnet. Figure 2 As shown, the first electromagnet 5 cooperates with the first suction patch 5A, and the second electromagnet 6 cooperates with the second suction patch 6A. The electromagnet and the suction patch are respectively installed on different bilateral support units, and the stiffness of the positive and negative Poisson's ratio units is controlled by electromagnetic control.

[0071] The adjustable stiffness and Poisson's ratio metamaterial structural unit designed by the present invention is a two-dimensional microstructure configuration of coupled adjustable stiffness positive and negative Poisson's ratio units of mechanical metamaterials, and has extraordinary mechanical properties.

[0072] The adjustable stiffness and Poisson's ratio of the overall structure of the vibration isolator are designed based on the positive Poisson's ratio unit structure and the negative Poisson's ratio unit structure. From the stiffness and Poisson's ratio characteristics of the material, it can be seen that the stiffness reflects the ability of the material to resist elastic deformation, that is, the difficulty of elastic deformation, while the Poisson's ratio reflects the elastic deformation form of the material, that is, the ratio between the lateral positive strain and the axial positive strain. In order to achieve adjustable stiffness and Poisson's ratio, it is considered to combine two structures with positive and negative Poisson's ratios, and adjust the stiffness of the two structures separately through local stiffening, so that the adjustable stiffness and Poisson's ratio metamaterial structural unit reflects different stiffness and Poisson's ratio. The positive and negative Poisson's ratio units in the adjustable stiffness and Poisson's ratio metamaterial structural unit both undergo telescopic deformation at the outer boss, and the realization of the Poisson's ratio is carried by the support structure (3, 4), which transfers the load to the deformation structure of the positive and negative Poisson's ratio units. The deformation of the deformation structure causes the virtual telescopic structure to expand and contract, resulting in changes in the overall size of the adjustable stiffness and Poisson's ratio metamaterial structural unit.

[0073] Poisson's ratio unit 1

[0074] See also Figure 1 , Figure 1A , Figure 1B , Figure 2 , Figure 2A As shown, the positive Poisson's ratio unit 1 is an integrally formed hexagonal structural member. The positive Poisson's ratio unit 1 is provided with an A upper connecting plate 1A, A right upper supporting arm 1B, A right lower supporting arm 1C, A lower connecting plate 1D, A left lower supporting arm 1E, A left upper supporting arm 1F, A right outer boss 1G and A left outer boss 1H.

[0075] Among them, the right upper arm 1B of A and the right lower arm 1C of A are inclined outwards on the same side.

[0076] The left upper arm 1F of A and the left lower arm 1E of A are inclined outwards on the same side.

[0077] Among them, the right outer boss 1G of A is arranged outside the junction of the right upper arm 1B of A and the right lower arm 1C of A.

[0078] Among them, the A left outer boss 1H is arranged outside the junction of the A left upper arm 1F and the A left lower arm 1E.

[0079] The A upper connecting plate 1A is provided with an AA threaded hole 1A1 for screws to pass through. The A upper connecting plate 1A is placed in an open U-shaped groove of a bilateral support unit of a metamaterial structural unit with adjustable stiffness and Poisson's ratio ( Figure 5 The fixed connection is achieved by combining screws, nuts and threaded holes.

[0080] The A lower connecting plate 1D is provided with an AB threaded hole 1D1 for screws to pass through. The A lower connecting plate 1D is placed in the open U-shaped groove 3F of the first bilateral supporting unit 3 .

[0081] Negative Poisson's ratio unit 2

[0082] See also Figure 1 , Figure 1A , Figure 1B , Figure 2 , Figure 2B As shown, the negative Poisson's ratio unit 2 is an integrally formed hexagonal structural member. The negative Poisson's ratio unit 2 is provided with a B upper connecting plate 2A, a B right upper arm 2B, a B right lower arm 2C, a B lower connecting plate 2D, a B left lower arm 2E, a B left upper arm 2F, a B right outer boss 2G and a B left outer boss 2H.

[0083] Among them, the right upper arm 2B of B and the right lower arm 2C of B are inclined inwardly on the same side.

[0084] Among them, the left upper arm 2F of B and the left lower arm 2E of B are inclined inwardly on the same side.

[0085] Among them, the right outer boss 2G of B is arranged outside the junction of the right upper arm 2B of B and the right lower arm 2C of B.

[0086] Among them, the B left outer boss 2H is arranged outside the junction of the B left upper arm 2F and the B left lower arm 2E.

[0087] The B upper connecting plate 2A is provided with a BA threaded hole 2A1 for screws to pass through. The B upper connecting plate 2A is placed in the open U-shaped groove 3F of the A bilateral supporting unit 3 .

[0088] The B lower connecting plate 2D is provided with a BB threaded hole 2D1 for screws to pass through. The B lower connecting plate 2D is placed in the open U-shaped groove 4F of the second bilateral supporting unit 4.

[0089] like Figure 2A , Figure 2BThe dimensions of the positive Poisson's ratio unit 1 and the negative Poisson's ratio unit 2 designed by the present invention are as follows: the length of the connecting plate is recorded as h, the width of the connecting plate is recorded as b (the width b is also the thickness of the entire Poisson's ratio unit), and the thickness of the connecting plate is recorded as w2; the length of the support arm is recorded as l, the width of the support arm is also b, and the thickness of the support arm is recorded as t; the length of the outer boss is recorded as d, the width of the outer boss is also b, and the thickness of the outer boss is recorded as w1 (w1=2(w2)); the angle between the support arm and the connecting plate in the positive Poisson's ratio unit 1 is recorded as θ1; the angle between the support arm and the connecting plate in the negative Poisson's ratio unit 2 is recorded as θ2 (θ2=θ1). The stiffness of the positive Poisson's ratio unit 1 and the negative Poisson's ratio unit 2 is mainly determined by the thickness (t) and angle (θ2=θ1) of the support arm, and the Poisson's ratio is mainly determined by the angle (θ2=θ1) and the overall size of the adjustable stiffness and Poisson's ratio metamaterial structure unit. Assuming that a single adjustable stiffness and Poisson's ratio metamaterial structural unit undergoes a small longitudinal displacement of 2δ, the lateral displacement can be obtained based on the invariance of the length (l) of the arm: The angle between the support arm and the connecting plate is θ (θ=θ1=θ2).

[0090] In the present invention, the size of the bilateral support unit (3, 4) is designed according to the size of the positive Poisson's ratio unit 1 and the negative Poisson's ratio unit 2, so as to obtain the overall size of the adjustable stiffness and Poisson's ratio metamaterial structural unit. Based on the Abaqus simulation software, the positive Poisson's ratio unit 1 and the negative Poisson's ratio unit 2 are subjected to finite element simulation analysis, and their structures are optimized to obtain the lateral strain ε of the Poisson's ratio unit. 1 and longitudinal strain ε 2 They are:

[0091]

[0092]

[0093] The Poisson's ratio ν is obtained from the ratio of the transverse strain to the longitudinal strain n for:

[0094]

[0095] Positive Poisson's ratio unit 1 Corrected Poisson's ratio ν 正 The expression is:

[0096]

[0097] Negative Poisson's ratio unit 2 Corrected Poisson's ratio ν 负 The expression is:

[0098]

[0099] Observe the expression of Poisson's ratio and stiffness. When the size of positive Poisson's ratio unit 1 and negative Poisson's ratio unit 2 is designed to be the same, the Poisson's ratio is completely determined and the stiffness is only determined by the thickness of the arm. Based on the modified unit Poisson's ratio formula, the Poisson's ratio of different application scenarios of the vibration isolator can be further optimized according to the cross arrangement of adjustable stiffness and Poisson's ratio metamaterial structural units.

[0100] In the present invention, the overall stiffness and Poisson's ratio of the adjustable stiffness and Poisson's ratio metamaterial structural unit structure can be adjusted, that is, the stiffness of the two units is used to achieve this. And the overall stiffness of the structure satisfies that it also increases or decreases as the stiffness of any unit increases or decreases. Stiffness and Poisson's ratio are essentially deformation characteristics of reactive materials. In order to achieve the adjustability of stiffness and Poisson's ratio, the present invention adopts a combination of positive and negative Poisson's ratio structural units, and achieves the rigidification of different units by adjusting the stiffness of different units respectively, so that the adjustable stiffness and Poisson's ratio metamaterial structural unit exhibits the characteristics of positive or negative Poisson's ratio, and also realizes the regulation of overall stiffness, which provides a new design idea for the design of metamaterials with adjustable stiffness and Poisson's ratio.

[0101] First bilateral support unit 3

[0102] See also Figure 1 , Figure 1A , Figure 1B , Figure 2 , Figure 3 As shown, the first bilateral support unit 3 is an integrally formed structural member. The first bilateral support unit 3 is provided with a CA arc-shaped clamp arm 3A, a CB arc-shaped clamp arm 3B, a C clamping upper plate 3D, a C clamping lower plate 3E, and a C magnet mounting panel 3G. The upper portion of the first bilateral support unit 3 is an upper opening portion formed by the CA arc-shaped clamp arm 3A and the CB arc-shaped clamp arm 3B, the middle portion of the first bilateral support unit 3 is a clamping middle portion formed by the C clamping upper plate 3D and the C clamping lower plate 3E, and the lower portion of the first bilateral support unit 3 is a C magnet mounting panel 3G. See Figure 1B As shown, the right end face of the upper opening portion is located in the plane of the vertical axis center line; the left end face of the C magnet mounting panel 3G is located in the plane of the vertical axis center line; the bilateral support unit designed with the reference mounting surface formed by the vertical axis center line can, during the assembly process of the isolator, on the one hand, make each column of the arrayed multiple adjustable stiffness and Poisson's ratio metamaterial structural units remain on the same vertical axis center line, on the other hand, maintain the structure of a single adjustable stiffness and Poisson's ratio metamaterial structural unit, and the third aspect is that it can facilitate the installation and removal of the electromagnet and the suction patch.

[0103] Among them, a CA through hole 3A1 is provided on one end of the CA arc-shaped clamp arm 3A, a CB through hole 3B1 is provided on one end of the CB arc-shaped clamp arm 3B, and a C open through hole 3C is provided between the CA arc-shaped clamp arm 3A and the CB arc-shaped clamp arm 3B. The C open through hole 3C is used to place the first electromagnet 5, and the first electromagnet 5 is fixed to the upper opening of the first bilateral support unit 3 by placing studs in the CA through hole 3A1 and the CB through hole 3B1 and sleeve nuts on the studs.

[0104] There is a C-open U-shaped groove 3F between the C-clamping upper plate 3D and the C-clamping lower plate 3E, and the C-open U-shaped groove 3F is used to place the A lower connecting plate 1D of the positive Poisson's ratio unit 1 and the upper connecting plate 2A of the negative Poisson's ratio unit 2B, such as Figure 1 shown.

[0105] The C magnet mounting panel 3G is provided with a C countersunk cavity 3G1, and a C center through hole 3G2 is provided in the middle of the C countersunk cavity 3G1 for wiring. A B attracting patch 6A is installed in the C countersunk cavity 3G1 for generating driving force with the second electromagnet 6 after power is turned on.

[0106] Second bilateral support unit 4

[0107] See also Figure 1 , Figure 1A , Figure 1B , Figure 2 , Figure 4 As shown, the second bilateral support unit 4 is an integrally formed structural member. The second bilateral support unit 4 is provided with a DA arc-shaped clamp arm 4A, a DB arc-shaped clamp arm 4B, a D clamping upper plate 4D, a D clamping lower plate 4E, and a D magnet mounting panel 4G. The upper portion of the second bilateral support unit 4 is an upper opening portion formed by the DA arc-shaped clamp arm 4A and the DB arc-shaped clamp arm 4B, the middle portion of the second bilateral support unit 4 is a clamping middle portion formed by the D clamping upper plate 4D and the D clamping lower plate 4E, and the lower portion of the second bilateral support unit 4 is a D magnet mounting panel 4G.

[0108] Among them, a DA through hole 4A1 is provided on one end of the DA arc-shaped clamp arm 4A, a DB through hole 4B1 is provided on one end of the DB arc-shaped clamp arm 4B, and a D opening through hole 4C is provided between the DA arc-shaped clamp arm 4A and the DB arc-shaped clamp arm 4B. The D opening through hole 4C is used to place the second electromagnet 6, and the second electromagnet 6 is fixed to the upper opening of the second bilateral support unit 4 by placing studs in the DA through hole 4A1 and the DB through hole 4B1 and sleeved with nuts on the studs.

[0109] Among them, between the D clamping upper plate 3D and the D clamping lower plate 4E is a D open U-shaped groove 4F, and the D open U-shaped groove 4F is used to place the B lower connecting plate 2D of the negative Poisson's ratio unit 2 and the upper connecting plate of the positive Poisson's ratio unit of another adjustable stiffness and Poisson's ratio metamaterial structure unit ( Figure 5 shown).

[0110] The D magnet mounting panel 4G is provided with a D countersunk cavity 4G1, and a D central through hole 4G2 is provided in the middle of the D countersunk cavity 4G1 for wiring. Another suction patch is installed in the D countersunk cavity 4G1.

[0111] The single adjustable stiffness and Poisson's ratio metamaterial structural unit designed in the present invention has two states: locked and free. The mechanical properties thereof can be adjusted by controlling the states of the positive and negative Poisson's ratio units respectively.

[0112] Vibration Isolators

[0113] The positive and negative Poisson's ratio units are made of TPU material, and the bilateral support units are made of resin material.

[0114] In order to achieve the independent deformation of the positive and negative Poisson's ratios and make their respective lateral deformations affect the deformation of the overall structure of the adjustable stiffness and Poisson's ratio metamaterial structural unit, it is necessary to connect its virtual telescopic structure with the supporting structure, and separate the deformation structures of the two, so that the telescopic effect of the positive and negative Poisson's ratio units can be reflected in the overall structure of the adjustable stiffness and Poisson's ratio metamaterial structural unit. In addition, it is necessary to consider that when one unit in the structure is mainly deformed, the size of the other unit does not restrict the overall size, so it is necessary to cross-arrange the two units, such as Figure 5 The lateral dimensions of the vibration isolator formed by the positive and negative Poisson's ratio coupling structure shown will be jointly determined by the virtual telescopic structures in the positive and negative Poisson's ratio units.

[0115] exist Figure 5 In the vibration isolator structure shown, in order to achieve balanced upper and lower forces of the vibration isolator, an upper force-bearing member 7 and an upper matching plate 70 are provided at the upper part of the vibration isolator, and a lower force-bearing member 8 and a lower matching plate 80 are provided at the lower part of the vibration isolator. In the present invention, the upper force-bearing member 7 and the lower force-bearing member 8 are cut from a complete bilateral support unit, and the upper force-bearing member 7 and the lower force-bearing member 8 are used in conjunction with the adjustable stiffness and Poisson's ratio metamaterial structural unit.

[0116] Upper load bearing member 7

[0117] See also Figure 5 , Figure 5A , Figure 5B , Figure 5CAs shown, the upper force-bearing member 7 is an integrally formed structural member. The upper force-bearing member 7 is provided with a G clamping upper plate 7D, a G clamping lower plate 7E, and a G magnet mounting panel 7G. The upper force-bearing member 7 is provided with a G clamping upper plate 7D, a G clamping lower plate 7E, and a G magnet mounting panel 7G; between the G clamping upper plate 7D and the G clamping lower plate 7E is a G open U-shaped groove 7F, and the G open U-shaped groove 7F is used to place an upper matching plate 70 and an upper connecting plate of a negative Poisson's ratio unit of an adjustable stiffness and Poisson's ratio metamaterial structural unit, as shown in FIG. Figure 5 As shown; or it is an upper connecting plate of a positive Poisson's ratio unit of an adjustable stiffness and Poisson's ratio metamaterial structural unit. The G magnet mounting panel 7G is provided with a G countersunk cavity 7G1, and a G center through hole 7G2 is provided in the middle of the G countersunk cavity 7G1, and the G center through hole 7G2 is used for wiring. An absorbent patch is installed in the G countersunk cavity 7G1, such as Figure 5 shown.

[0118] Lower load bearing member 8

[0119] See also Figure 5 , Figure 5A , Figure 5D , Figure 5E As shown, the lower force bearing member 8 is an integrally formed structural member. The lower force bearing member 8 is provided with an HA arc-shaped clamping arm 8A, an HB arc-shaped clamping arm 8B, an H clamping upper plate 8D, and an H clamping lower plate 8E.

[0120] Among them, a HA through hole 8A1 is provided on one end of the HA arc-shaped clamp arm 8A, a HB through hole 8B1 is provided on one end of the HB arc-shaped clamp arm 8B, and an H opening through hole 8C is provided between the HA arc-shaped clamp arm 8A and the HB arc-shaped clamp arm 8B. An electromagnet is placed in the H opening through hole 8C, and the electromagnet is fixed to the upper opening of the lower force-bearing member 8 by placing studs in the HA through hole 8A1 and the HB through hole 8B1 and sleeved with nuts on the studs.

[0121] Among them, between the H clamping upper plate 3H and the H clamping lower plate 8E is an H-open U-shaped groove 8F, and the H-open U-shaped groove 8F is used to place the lower matching plate 80 and the upper connecting plate of the negative Poisson's ratio unit of the adjustable stiffness and Poisson's ratio metamaterial structural unit, such as Figure 5 As shown; or an upper connecting plate of a positive Poisson's ratio unit of a metamaterial structural unit with adjustable stiffness and Poisson's ratio.

[0122] The vibration isolator is based on the obtained positive and negative Poisson's ratio coupling structure, and further considers the control strategy of the stiffness of the positive and negative Poisson's ratio units. The control strategy is divided into continuous and discontinuous control. The continuous control strategy can realize the continuous control of the mechanical properties of the structure, and the discontinuous control can realize the discrete control of the mechanical properties through different arrangements. Taking electromagnetic control as an example, the state of the positive and negative Poisson's ratio units can be controlled with the help of electromagnets, so that each unit can independently present two states of low stiffness and high stiffness. Assuming the low stiffness state as the free state and the high stiffness state as the locked state, all the negative Poisson's ratio units in the vibration isolator are locked, then the vibration isolator will present the positive Poisson's ratio characteristics, and all the positive Poisson's ratio units in the vibration isolator are locked, and the vibration isolator will present the negative Poisson's ratio characteristics. In addition, when all positive and negative Poisson's ratio units are in a free state or a locked state, the vibration isolator will present the characteristics of a near-zero Poisson's ratio, but the structural stiffness is different in the two cases.

[0123] The split vibration isolator structure is more convenient for industrial manufacturing and installation, as well as disassembly and replacement. The electromagnet and the suction patch can be installed on the double-sided support unit respectively, and then the positive and negative Poisson's ratio unit can be installed. Figure 6 , Figure 7 , Figure 8 The overall deformation of the isolator in three states, free, positive Poisson's ratio, and negative Poisson's ratio, is presented. It can be intuitively seen that the deformation characteristics of the isolator are in line with expectations. Different colors in the figure represent lateral displacements of different sizes and directions. It should be noted that in order to more clearly present the deformation effect, the deformation is magnified in the figure.

[0124] Taking the 5×5 structure as an example, the loading method is that each surface of the upper and lower boundaries bears equal pressure, and the overall deformation of the structure under the negative Poisson's ratio is as follows: Fig. 9 As shown in the figure. The figure reflects the deformation of the positive Poisson's ratio unit in the vibration isolator when it is in a locked state and the whole load is loaded. It can be seen that the positive Poisson's ratio unit in the vibration isolator almost no longer participates in the deformation, so the deformation of the vibration isolator is mainly reflected by the negative Poisson's ratio structure, so the vibration isolator exhibits the characteristics of negative Poisson's ratio. The deformation curve obtained by recording the lateral deformation and longitudinal deformation data during the loading process is as follows Fig.10 As shown in the figure, the horizontal and vertical coordinates represent the axial deformation (i.e., the loading direction) and the lateral deformation respectively. Taking the vibration isolator with the dimensions of 238 mm in the axial direction and 322 mm in the lateral direction as an example, the negative Poisson's ratio is -1.15.

[0125] Taking the 5×5 structure as an example, the loading method is that each surface of the upper and lower boundaries bears equal pressure, and the overall deformation of the structure under the positive Poisson's ratio is as follows: Fig.11 As shown. The isolator is in a positive Poisson's ratio state, that is, the negative Poisson's ratio unit is locked and the positive Poisson's ratio unit is free. After the pressure is loaded, the axial deformation and the lateral deformation are also linearly related, as shown in Fig.12 shown.

[0126] by Fig. 9 and Fig.11 The loading method does not take the boundary conditions into consideration, but applies the same load to each upper and lower surface. But in fact, when the isolator is deformed, not every surface of the boundary is directly subjected to force, but the protruding part of the structure is directly subjected to force, and then the force is transmitted to the non-direct contact structure through the internal structure. This is also related to the actual loading form. For example, the deformation of the loaded object itself and the unit scale of the metamaterial structure will affect the contact surface. For the 5×5 array structure of the isolator of the present invention, in order to reduce the error with the actual experiment, the loading method needs to be further optimized. For example, if only the protruding part is directly subjected to force on the boundary, the results in the two cases will change. According to the simulation results under the positive and negative Poisson's ratio states, it can be seen that there are obvious differences in the deformation of the internal structure and the boundary, which is related to the size and scale of the structure. When the scale of the structure reaches a certain amount, such differences will become more uniform. In addition, when all units are in a free state, the isolator structure as a whole will exhibit the characteristics of zero Poisson's ratio. At this time, the bearing surface will not be uneven. Therefore, considering uniform loading, the following is obtained. Fig.13 The simulation results are shown in Figure 2. In the simulation where all units are in a free state, it can be seen that both positive and negative Poisson's ratio units participate in the deformation. If the protrusion of the positive Poisson's ratio unit under pressure at the boundary is ignored, the vibration isolator can be considered to be in a zero Poisson's ratio state. Based on the simulation results, the stiffness and Poisson's ratio of the vibration isolator can be obtained, as shown in Figure 2. Fig.14 As shown in the figure, the axial displacement load curves under three states are shown. According to the curves, the overall stiffness of the isolator structure under different states can be obtained. The overall stiffness of the structure is related to the proportion of units in the structure that are locked. When the proportion increases, it means that the area in the structure that is prone to deformation decreases, so the overall deformation of the structure will also become smaller, which increases the overall stiffness, and vice versa. Therefore, between the two states of full freedom and full locking, the overall stiffness can also be adjusted by controlling the proportion of locked units in the isolator. The arrangement of different units can achieve a combination of stiffness and Poisson's ratio adjustment, so that the isolator structure has more modes.

Claims

1. A vibration isolator based on adjustable stiffness and Poisson's ratio metamaterial, the vibration isolator is composed of a plurality of adjustable stiffness and Poisson's ratio metamaterial structural units arranged in an array; characterized in that: The adjustable stiffness and Poisson's ratio metamaterial structural unit is composed of a positive Poisson's ratio unit (1), a negative Poisson's ratio unit (2), a first bilateral support unit (3), a second bilateral support unit (4), a first electromagnet (5) and a second electromagnet (6); The difference between the positive Poisson's ratio unit (1) and the negative Poisson's ratio unit (2) lies in the convex or concave arrangement of the upper and lower arms on the same side; The first bilateral support unit (3) and the second bilateral support unit (4) have the same structure, and are installed at the same position in the adjustable stiffness and Poisson's ratio metamaterial structure unit; The positive Poisson's ratio unit (1) is provided with an A upper connecting plate (1A), A right upper supporting arm (1B), A right lower supporting arm (1C), A lower connecting plate (1D), A left lower supporting arm (1E), A left upper supporting arm (1F), A right outer boss (1G) and A left outer boss (1H); The upper arm (1B) on the right side of A and the lower arm (1C) on the right side of A are inclined outwards on the same side; The left upper arm (1F) of A and the left lower arm (1E) of A are inclined outwards on the same side; Wherein, the right outer boss (1G) of A is arranged outside the junction of the right upper support arm (1B) of A and the right lower support arm (1C) of A; Wherein, the A left outer boss (1H) is arranged outside the junction of the A left upper arm (1F) and the A left lower arm (1E); A connecting plate (1A) is placed in an open U-shaped groove of a bilateral support unit of a metamaterial structural unit with adjustable stiffness and Poisson's ratio; A lower connecting plate (1D) is placed in the open U-shaped groove (3F) of the first bilateral supporting unit (3); The negative Poisson's ratio unit (2) is provided with a B upper connecting plate (2A), a B right upper supporting arm (2B), a B right lower supporting arm (2C), a B lower connecting plate (2D), a B left lower supporting arm (2E), a B left upper supporting arm (2F), a B right outer boss (2G) and a B left outer boss (2H); Wherein, the right upper arm (2B) of B and the right lower arm (2C) of B are inclined inwards on the same side; The upper arm (2F) on the left side of B and the lower arm (2E) on the left side of B are inclined inwards on the same side; Wherein, the right outer boss (2G) of B is arranged outside the junction of the right upper arm (2B) of B and the right lower arm (2C) of B; Wherein, the B left outer boss (2H) is arranged outside the junction of the B left upper arm (2F) and the B left lower arm (2E); The upper connecting plate (2A) of B is placed in the open U-shaped groove (3F) of the double-sided supporting unit (3) of A; B The lower connecting plate (2D) is placed in the open U-shaped groove (4F) of the second bilateral supporting unit (4); The first bilateral support unit (3) is provided with a CA arc-shaped clamping arm (3A), a CB arc-shaped clamping arm (3B), a C clamping upper plate (3D), a C clamping lower plate (3E), and a C magnet installation panel (3G); the upper portion of the first bilateral support unit (3) is an upper opening portion formed by the CA arc-shaped clamping arm (3A) and the CB arc-shaped clamping arm (3B), the middle portion of the first bilateral support unit (3) is a clamping middle portion formed by the C clamping upper plate (3D) and the C clamping lower plate (3E), and the lower portion of the first bilateral support unit (3) is the C magnet installation panel (3G); the upper The right end surface of the opening is located in the plane of the vertical axis centerline; the left end surface of the C magnet mounting panel (3G) is located in the plane of the vertical axis centerline; the bilateral support unit designed with the reference mounting surface formed by the vertical axis centerline can, during the assembly process of the vibration isolator, on the one hand, keep each column of the arrayed multiple adjustable stiffness and Poisson's ratio metamaterial structural units on the same vertical axis centerline, on the other hand, maintain the structure of a single adjustable stiffness and Poisson's ratio metamaterial structural unit, and thirdly, facilitate the installation and removal of the electromagnet and the suction patch; A CA through hole (3A1) is provided on one end of the CA arc-shaped clamp arm (3A), a CB through hole (3B1) is provided on one end of the CB arc-shaped clamp arm (3B), and a C-opening through hole (3C) is provided between the CA arc-shaped clamp arm (3A) and the CB arc-shaped clamp arm (3B); the C-opening through hole (3C) is used to place the first electromagnet (5), and studs are placed in the CA through hole (3A1) and the CB through hole (3B1), and nuts are sleeved on the studs to fix the first electromagnet (5) to the upper opening of the first bilateral support unit (3); Wherein, a C-opening U-shaped groove (3F) is provided between the C-clamping upper plate (3D) and the C-clamping lower plate (3E), and the C-opening U-shaped groove (3F) is used to place the A-lower connecting plate (1D) of the positive Poisson's ratio unit (1) and the upper connecting plate (2A) of the negative Poisson's ratio unit (2B); A C countersunk cavity (3G 1) is provided on the C magnet installation panel (3G), a C center through hole (3G2) is provided in the middle of the C countersunk cavity (3G 1), and the C center through hole (3G2) is used for wiring; a B suction patch (6A) is installed in the C countersunk cavity (3G 1) for generating a driving force with the second electromagnet (6) after power is turned on; The second bilateral support unit (4) is provided with a DA arc-shaped clamping arm (4A), a DB arc-shaped clamping arm (4B), a D clamping upper plate (4D), a D clamping lower plate (4E), and a D magnet installation panel (4G); the upper part of the second bilateral support unit (4) is an upper opening formed by the DA arc-shaped clamping arm (4A) and the DB arc-shaped clamping arm (4B), the middle part of the second bilateral support unit (4) is a clamping middle part formed by the D clamping upper plate (4D) and the D clamping lower plate (4E), and the lower part of the second bilateral support unit (4) is the D magnet installation panel (4G); A DA through hole (4A1) is provided on one end of the DA arc-shaped clamp arm (4A), a DB through hole (4B1) is provided on one end of the DB arc-shaped clamp arm (4B), and a D open through hole (4C) is provided between the DA arc-shaped clamp arm (4A) and the DB arc-shaped clamp arm (4B); the D open through hole (4C) is used to place the second electromagnet (6), and studs are placed in the DA through hole (4A1) and the DB through hole (4B1), and nuts are sleeved on the studs to fix the second electromagnet (6) to the upper opening of the second bilateral support unit (4); Wherein, between the D clamping upper plate (3D) and the D clamping lower plate (4E) is a D open U-shaped groove (4F), and the D open U-shaped groove (4F) is used to place the B lower connecting plate (2D) of the negative Poisson's ratio unit (2) and the upper connecting plate of the positive Poisson's ratio unit of another adjustable stiffness and Poisson's ratio metamaterial structure unit; A D countersunk head cavity (4G 1) is provided on the D magnet mounting panel (4G), a D center through hole (4G2) is provided in the middle of the D countersunk head cavity (4G 1), and the D center through hole (4G2) is used for wiring; another suction patch is installed in the D countersunk head cavity (4G 1).

2. The vibration isolator based on adjustable stiffness and Poisson's ratio metamaterial according to claim 1, characterized in that: In order to achieve balanced upper and lower forces on the vibration isolator, an upper force-bearing member (7) and an upper matching plate (70) are provided at the upper part of the vibration isolator, and a lower force-bearing member (8) and a lower matching plate (80) are provided at the lower part of the vibration isolator; the upper force-bearing member (7) and the lower force-bearing member (8) are used in conjunction with an adjustable stiffness and Poisson's ratio metamaterial structural unit; The upper force-bearing member (7) is provided with a G clamping upper plate (7D), a G clamping lower plate (7E), and a G magnet installation panel (7G); the upper force-bearing member (7) is provided with a G clamping upper plate (7D), a G clamping lower plate (7E), and a G magnet installation panel (7G); between the G clamping upper plate (7D) and the G clamping lower plate (7E) is a G open U-shaped groove (7F); the G open U-shaped groove (7F) is used to place an upper matching plate (70) and an upper connecting plate of a negative Poisson's ratio unit of an adjustable stiffness and Poisson's ratio metamaterial structural unit; or an upper connecting plate of a positive Poisson's ratio unit of an adjustable stiffness and Poisson's ratio metamaterial structural unit; the G magnet installation panel (7G) is provided with a G countersunk cavity (7G 1); the middle part of the G countersunk cavity (7G 1) is provided with a G center through hole (7G2); the G center through hole (7G2) is used for wiring; the G countersunk cavity (7G 1) A suction patch is installed inside; The lower force-bearing member (8) is an integrally formed structural member; the lower force-bearing member (8) is provided with an HA arc-shaped clamping arm (8A), an HB arc-shaped clamping arm (8B), an H clamping upper plate (8D), and an H clamping lower plate (8E); One end of the HA arc-shaped clamp arm (8A) is provided with a HA through hole (8A1), one end of the HB arc-shaped clamp arm (8B) is provided with a HB through hole (8B1), and an H open through hole (8C) is provided between the HA arc-shaped clamp arm (8A) and the HB arc-shaped clamp arm (8B); an electromagnet is placed in the H open through hole (8C), and studs are placed in the HA through hole (8A1) and the HB through hole (8B1), and nuts are sleeved on the studs to fix the electromagnet to the upper opening of the lower force-bearing member (8); There is an H-open U-shaped groove (8F) between the H-clamping upper plate (3H) and the H-clamping lower plate (8E), and the H-open U-shaped groove (8F) is used to place a lower matching plate (80) and an upper connecting plate of a negative Poisson's ratio unit of an adjustable stiffness and Poisson's ratio metamaterial structural unit; or an upper connecting plate of a positive Poisson's ratio unit of an adjustable stiffness and Poisson's ratio metamaterial structural unit.

3. The vibration isolator based on adjustable stiffness and Poisson's ratio metamaterial according to claim 1 or 2, characterized in that: The positive and negative Poisson's ratio units are made of TPU material, and the bilateral support units are made of resin material.

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