Pneumatic adjustable vibration absorber based on paper folding structure and regulation and control method thereof

Abstract

The invention belongs to the technical field of beam dynamic vibration absorption, and particularly relates to a pneumatic adjustable vibration absorber based on a paper folding structure and a regulation and control method of the pneumatic adjustable vibration absorber. The vibration absorber comprises a Yoshimura paper folding structure, an air bag, an additional mass block, an upper circular acrylic plate, a middle circular acrylic plate, a lower circular acrylic plate, an air pipe and an electromagnetic proportional valve. The two ends of the air bag are connected with the middle circular acrylic plate and the lower circular acrylic plate, the Yoshimura paper folding structure is connected with the middle circular acrylic plate and the lower circular acrylic plate and wraps the outer side of the air bag, the additional mass block is fixed to the upper circular acrylic plate, the upper circular acrylic plate is connected with the middle circular acrylic plate, and the two ends of the air pipe are connected with the air bag and the electromagnetic proportional valve respectively. A plurality of pneumatic paper folding vibration absorbers are arranged on a beam structure, band gap regulation and control and vibration suppression of the beam structure can be realized by changing internal air pressure of the vibration absorbers and meeting a periodic arrangement rule, and active regulation and control of wave transmission and vibration characteristics of the beam structure are realized through active regulation and control of light weight and inherent frequency of the vibration absorbers.

Description

Technical Field

[0001] This invention belongs to the field of beam dynamic vibration absorption technology, specifically relating to a pneumatically adjustable vibration absorber based on a paper-folding structure and its control method. Background Technology

[0002] The main drawback of traditional passive vibration absorbers is their narrow effective operating frequency band; once designed, their operating characteristics cannot be altered. Therefore, with the emergence of various complex working conditions, active vibration absorbers require external power to adjust their stiffness or damping, thereby changing their natural frequency. Existing active vibration absorbers are generally electromagnetic, and their mass and size largely depend on the size of the electromagnet, which limits their application range. Therefore, it is necessary to design a vibration absorber based on a novel structure and driving method, apply it to beam structures, and propose corresponding control strategies. Summary of the Invention

[0003] The purpose of this invention is to provide a pneumatically adjustable vibration absorber based on origami structure and its control method, so as to overcome the defects of the prior art.

[0004] The pneumatically adjustable vibration absorber based on an origami structure (hereinafter referred to as the pneumatically origami vibration absorber) provided by this invention is an active vibration absorber arranged on a beam structure; specifically, it includes a pneumatically origami-structured vibration absorber and an electromagnetic proportional valve; see [link to related documentation]. Figure 1 As shown; where:

[0005] The pneumatic vibration absorber with the origami structure has an acrylic plate at its bottom and a beam structure connected by bolts. The number of pneumatic vibration absorbers based on the origami structure arranged on the beam structure can be one or more, such as two, three, four, five, six, seven, etc., with each vibration absorber arranged at equal intervals.

[0006] The aforementioned pneumatic vibration absorber based on origami structure consists of an airbag, air tubes, a Yoshimura origami structure, bolts, studs, a counterweight block, and three circular acrylic plates (arranged as upper, middle, and lower sections); wherein:

[0007] The airbag is cylindrical and made of PVC film. The upper end is fixed to the middle circular acrylic plate with hot melt adhesive and is fixed at the center of the middle circular acrylic plate. The lower end of the airbag is also fixed to the center of the lower circular acrylic plate with hot melt adhesive. The cylindrical airbag is perpendicular to the middle and lower acrylic plates.

[0008] Bolt holes are provided on the outer sides of the upper, middle and lower circular acrylic sheets, and a circular hole is provided in the center of the lower circular acrylic sheet;

[0009] One end of the air tube is connected to the lower part of the airbag through a circular hole in the center of the lower circular acrylic plate and is fixed with hot melt adhesive. The other end of the air tube is connected to the air outlet of the electromagnetic proportional valve. The electromagnetic proportional valve is controlled by the host computer to change the air pressure.

[0010] The Yoshimura origami structure is made of PET film through laser cutting. Its two ends are fixed to the middle circular acrylic plate and the lower circular acrylic plate, respectively, and are all fixed with bolts. It is spatially surrounded on the outside of the cylindrical airbag.

[0011] The counterweight mass block is connected and fixed by bolts and an upper acrylic plate;

[0012] The upper and middle circular acrylic panels are fixed with four studs.

[0013] This invention also provides a method for controlling an active pneumatically adjustable vibration absorber applied to beam structures, comprising the following steps:

[0014] (1) The adjustable vibration absorption frequency of the pneumatic adjustable vibration absorber was calibrated. Its natural frequency under different air pressures was obtained using an exciter test. The natural frequency of the vibration absorber and the air pressure showed an approximately linear relationship. Experimental tests showed that when the absolute air pressure inside the vibration absorber varied between 0.107 MPa and 0.17 MPa, the natural frequency of the vibration absorber ranged from 11.78 Hz to 53.94 Hz, and the two showed an approximately linear relationship. See also... Figure 5 As shown;

[0015] (2) Control of wave transmission characteristics of beam structure: For beam structure as carrier of elastic wave transmission, it is necessary to significantly increase the number of vibration absorbers arranged on beam structure. Generally, 8-12 vibration absorbers are arranged within a unit length of meter of beam structure. Specifically, considering the different lengths of different beams and the size limitations of paper vibration absorbers, for example, when the beam length is 1m, if the paper vibration absorbers are arranged at intervals of 0.1m, the number of paper vibration absorbers arranged is 10.

[0016] Then, the periodic arrangement of the air pressure inside the vibration absorber is clarified. Specifically, assuming that S vibration absorbers form a unit, and there are N units in total, the internal air pressures of the S vibration absorbers in the first unit are P1, P2, ..., PS, and the internal air pressures of the S vibration absorbers in the subsequent N-1 units are arranged cyclically in the same manner as in the first unit. For example, if a period is selected containing two pneumatic paper-folding vibration absorbers, the air pressure inside the first vibration absorber is 0.10MPa, and the air pressure inside the second vibration absorber is 0.15MPa. The air pressures of the subsequent vibration absorbers are arranged cyclically according to this unit rule, that is, the overall system presents a periodic air pressure distribution characteristic of "0.10MPa, 0.15MPa, 0.10MPa, 0.15MPa...".

[0017] Based on the plane wave expansion method in the form of ω(q) (Xiao Yong. Research on bandgap control and vibration reduction characteristics of local resonant structures [D]. National University of Defense Technology, 2012), the bandgap distribution of the beam structure can be obtained. Then, based on the law of the periodic arrangement of air pressure inside the vibration absorber, the bandgap can be controlled by changing the air pressure inside each folded pneumatic vibration absorber. In Example 1, the air pressure of the first, third, fifth, seventh, and ninth folded pneumatic vibration absorbers is kept constant at 0.17 MPa, while the air pressure of the second, fourth, sixth, eighth, and tenth vibration absorbers gradually changes from 0.107 MPa to 0.17 MPa. The bandgap can be expanded from [44.75 Hz, 64.50 Hz] to [12.05 Hz, 64.50 Hz], and the adjustable bandgap width is increased to 2.6 times.

[0018] (3) Control of vibration characteristics of beam structure: For beam structure as the carrier of vibration transmission, it is necessary to determine the frequency of external excitation. Specifically, based on the relationship between the natural frequency and air pressure of the pneumatic origami vibration absorber obtained above, the internal air pressure is adjusted to make its natural frequency equal to the external excitation frequency, thereby achieving the vibration absorption effect. For example, in Example 2, only one pneumatic origami vibration absorber needs to be installed on the beam structure. As the external excitation frequency gradually increases from 11.77Hz to 46.58Hz, the pneumatic vibration absorber adjusts its own natural frequency to be equal to the external excitation frequency through air pressure control. Then, the vibration absorber can reduce the displacement transmission rate of the beam end by more than 10 times at most frequencies.

[0019] Compared with the prior art, the present invention has the following beneficial effects:

[0020] (1) The present invention designs a vibration absorber based on origami structure, with an airbag inside that can adjust the natural frequency of the vibration absorber by air pressure. The present invention achieves the lightweight and actively adjustable characteristics of the vibration absorber.

[0021] (2) By changing the air pressure inside the pneumatic origami vibration absorber, the air pressure values ​​of the vibration absorbers on the beam structure can be arranged in a periodic manner, thus achieving an adjustable bandgap structure.

[0022] (3) By changing the air pressure inside the pneumatic origami vibration absorber, the natural frequency of the vibration absorber is made equal to the external excitation frequency. Attached Figure Description

[0023] Figure 1 This is a diagram showing the overall layout of the pneumatic origami vibration absorber on the beam structure.

[0024] Figure 2 This refers to the connection method between the pneumatic origami vibration absorber and the beam structure.

[0025] Figure 3 This is a structural diagram of a pneumatic origami vibration absorber.

[0026] Figure 4 A crease design diagram for the Yoshimura origami structure.

[0027] Figure 5 The relationship between the natural frequency and air pressure of the pneumatic origami vibration absorber.

[0028] Figure 6 This is a schematic diagram of the control strategy for a pneumatic origami vibration absorber.

[0029] Figure 7 This is a bandgap distribution diagram of the beam structure in Example 1 under the control of the vibration absorber.

[0030] Figure 8 This is a schematic diagram of the structure of Example 2.

[0031] Figure 9 The graph shows the displacement transmissibility of the beam structure under the control of the vibration absorber in Example 2.

[0032] In the diagram, the numbers represent: 1 for beam structure, 2 for the first pneumatic origami vibration absorber, 3 for the second, 4 for the third, 5 for the fourth, 6 for the fifth, 7 for the sixth, 8 for the seventh, 9 for the eighth, 10 for the ninth, 11 for the tenth, 101 for connecting bolts, 102 for connecting bolts, 103 for connecting bolts, 104 for connecting bolts, 105 for connecting bolts, 106 for connecting bolts, 107 for connecting bolts, 108 for connecting bolts, 109 for connecting bolts, 110 for connecting bolts, 111 for connecting bolts, 112 for connecting bolts, 113 for connecting bolts, 114 for connecting bolts, 115 for connecting bolts, 116 for connecting bolts, and 117 for connecting bolts. 118 is a connecting bolt, 119 is a connecting bolt, 120 is a connecting bolt, 201 is an electromagnetic proportional valve, 202 is an air tube, 203 is a Yoshimura, 204 is a central circular acrylic plate, 205 is a lower circular acrylic plate, 206 is an upper circular acrylic plate, 207 is the first stud, 208 is the second stud, 209 is the third stud, 210 is the fourth stud, 211 is a thickening bolt, 212 is a counterweight block, 213 is a fixing bolt, 214 is a fixing bolt, 215 is a fixing bolt, 216 is a fixing bolt, 217 is a fixing bolt, 218 is a fixing bolt, 219 is a cylindrical airbag, 220 is a fixing bolt, 221 is a fixing bolt, 222 is a fixing bolt, 223 is a fixing bolt, 224 is a fixing bolt, and 225 is a fixing bolt. Detailed Implementation

[0033] The present invention will now be described in detail with reference to the accompanying drawings and specific embodiments. These embodiments are based on the technical solution of the present invention and provide detailed implementation methods and specific operating procedures. However, the scope of protection of the present invention is not limited to the following embodiments.

[0034] In the accompanying drawings, components with the same structure are indicated by the same numerical designation, and components with similar structures or functions are indicated by similar numerical designations. The dimensions and thicknesses of each component shown in the drawings are arbitrary, and the present invention does not limit the dimensions and thicknesses of each component. To make the illustrations clearer and show the mating relationships between the components, some parts in the drawings have been appropriately scaled down, and the distances between the components have been increased or decreased.

[0035] In the description of the embodiments of this application, it should be understood that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, or the orientation or positional relationship commonly placed when the product of this application is used, or the orientation or positional relationship commonly understood by those skilled in the art. They are only for the convenience of describing this application and simplifying the description, and are not intended to indicate or imply that the device or component referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this application.

[0036] Furthermore, the terms "first," "second," and "third" are used only to distinguish descriptions and should not be interpreted as indicating or implying relative importance.

[0037] In the description of the embodiments of this application, it should also be noted that, unless otherwise expressly specified and limited, the terms "set," "install," "connect," and "link" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this application based on the specific circumstances.

[0038] Example 1. A pneumatic origami vibration absorber arranged on a beam structure, such as Figure 1 As shown, the structure includes a beam structure 1, a first pneumatic origami vibration absorber 2, a second pneumatic origami vibration absorber 3, a third pneumatic origami vibration absorber 4, a fourth pneumatic origami vibration absorber 5, a fifth pneumatic origami vibration absorber 6, a sixth pneumatic origami vibration absorber 7, a seventh pneumatic origami vibration absorber 8, an eighth pneumatic origami vibration absorber 9, a ninth pneumatic origami vibration absorber 10, and a tenth pneumatic origami vibration absorber 11. The first, second, third, fourth, fifth, sixth, seventh, eighth, ninth, and tenth pneumatic origami vibration absorbers are all arranged vertically on the beam structure.

[0039] Specifically, such as Figure 2 As shown, the lower circular acrylic plate and beam structure 1 of the first pneumatic origami vibration absorber 2 are fixed together by bolts 101 and 102; the lower circular acrylic plate and beam structure 1 of the second pneumatic origami vibration absorber 3 are fixed together by bolts 103 and 104; the lower circular acrylic plate and beam structure 1 of the third pneumatic origami vibration absorber 4 are fixed together by bolts 105 and 106; the lower circular acrylic plate and beam structure 1 of the fourth pneumatic origami vibration absorber 5 are fixed together by bolts 107 and 108; and the lower circular acrylic plate and beam structure 1 of the fifth pneumatic origami vibration absorber 6 are fixed together by bolts 109 and 110. The lower circular acrylic plate and beam structure 1 of the sixth pneumatic origami vibration absorber 7 are fixed together by bolts 111 and 112; the lower circular acrylic plate and beam structure 1 of the seventh pneumatic origami vibration absorber 8 are fixed together by bolts 113 and 114; the lower circular acrylic plate and beam structure 1 of the eighth pneumatic origami vibration absorber 9 are fixed together by bolts 115 and 116; the lower circular acrylic plate and beam structure 1 of the ninth pneumatic origami vibration absorber 10 are fixed together by bolts 117 and 118; and the lower circular acrylic plate and beam structure 1 of the tenth pneumatic origami vibration absorber 11 are fixed together by bolts 119 and 120.

[0040] The specific design of the pneumatic origami vibration absorber is as follows: Figure 3 As shown, the additional mass block 212 is fixed to the upper circular acrylic plate 206 by thickened bolts 211. The upper circular acrylic plate 206 and the middle circular acrylic plate 204 are fixed by studs 207, 208, 209, and 210. The Yoshimura origami structure 203 is fabricated by laser cutting of PET film, and its specific crease pattern is as follows: Figure 4 As shown. The upper end and middle circular acrylic plate 204 of the Yoshimura origami structure 203 are connected by bolts 213, 214, 215, 216, 217, and 218, and the lower end and lower circular acrylic plate 205 are connected by bolts 220, 221, 222, 223, 224, and 225. The upper end of the cylindrical airbag 219 is fixed to the center of the middle circular acrylic plate 204 with hot melt adhesive, and the lower end of the airbag is fixed to the center of the middle circular acrylic plate 205 with hot melt adhesive. One end of the air tube 202 is connected to the cylindrical airbag 219 and is airtightened with hot melt adhesive; the other end of the air tube 202 is connected to the electromagnetic proportional valve 201, which can output the corresponding air pressure value based on the corresponding electrical signal.

[0041] The control of wave transmission and vibration in beam structures based on pneumatic origami vibration absorbers includes the following steps:

[0042] (1) The relationship between air pressure and stiffness of the pneumatic origami vibration absorber was determined. Specifically, the natural frequency of the pneumatic origami vibration absorber under different air pressures could be obtained through exciter testing. In this example, the air pressure range of 0.107MPa to 0.17MPa corresponds to a natural frequency range of 11.77Hz to 46.58Hz, and the two can be approximately represented by a linear relationship. The fitted curve is y = 543.27x - 46.27, as shown below. Figure 5 As shown. Then, the force-displacement curves of the pneumatic origami vibration absorber under different air pressures were obtained by testing with a universal tensile testing machine, and the corresponding stiffness was calculated. The parameters of the corresponding beam structure also need to be measured, including the beam's length, width, and height. The elastic model parameters of the beam can be obtained from the *Materials Handbook* based on its material. In this embodiment, the beam's length is 1m, width is 0.02m, height is 0.004m, and the material is aluminum (density 2700 kg / m³). 3 (The elastic modulus is 70 GPa), and the mass of a single vibration absorber is 20 g.

[0043] (2) Control of wave transmission characteristics of the beam structure: Under this condition, the number of pneumatic vibration absorbers arranged on the beam structure needs to be significantly increased. In this embodiment, the beam length is 1m, and the number of vibration absorbers is 10. Figure 1 As shown. Furthermore, the air pressure distribution of the vibration absorbers must also meet periodic conditions, and the vibration absorbers must be arranged at equal intervals. For example, Figure 6 (a) shows a scenario where two pneumatic origami vibration absorbers form one cycle (unit). The two absorbers have different air pressures, while the air pressures of the remaining pneumatic origami vibration absorbers are arranged according to the same pattern. After the absorbers are inflated, the band gap of the overall structure needs to be calculated using the plane wave expansion method in the form of ω(q). Taking the case where one cycle contains two pneumatic origami vibration absorbers as an example, the stiffness matrix K and mass matrix M of the overall structure need to be calculated first:

[0044]

[0045]

[0046] Where E is the elastic modulus of the beam structure, I is the moment of inertia of the beam section (I=bh3 / 12, b is the width of the beam section, h is the height of the beam section), A is the area of ​​the beam section (A=bh), a is the spacing between adjacent origami pneumatic vibration absorbers, ρ is the density of the beam, m is the total mass of a single vibration absorber, k1 and k2 are the stiffness of the first and second vibration absorbers (one cycle of the structure), x1 and x2 are the positions of the first and second vibration absorbers in the local coordinate system, M is the stage order (determined by the user according to the calculation accuracy), q is the wave vector (the value range is the irreducible Brillouin zone [0, π / a]), and i is the imaginary unit. In formula (2), matrix qM is a diagonal matrix. The horizontal and vertical ellipses both represent the number 0, and the diagonal ellipses indicate that the diagonal elements gradually increase from (q-2Mπ)4 to (q+2Mπ)4. In formula (3), the ellipsis indicates that the elements in the data vector Pj gradually increase from ei[q-2Mπ / a]xj to ei[q+2Mπ / a]xj, and the elements in the vector Pj' gradually decrease from ei[q-2Mπ / a]xj to ei[q+2Mπ / a]xj. In formula (4), I is the identity matrix, and both horizontal and vertical ellipsis represent the number 0, while diagonal ellipsis indicates that all diagonal elements are 1. Finally, according to the following equation:

[0047] (K-ω 2 M)X=0. (5) Perform eigenvalue solving. During the process of sequentially scanning the value of q, 2M+3 eigenvalue frequencies can be obtained, and the corresponding band structure can be obtained. The frequency range without eigenfrequency solutions in the band structure diagram is the band gap range. If the air pressure value is changed, k1 and k2 in the formula will change, and the overall band gap of the structure can naturally be adjusted. For the case where a cycle contains more pneumatic origami vibration absorbers, the calculation formula can be deduced by analogy.

[0048] In this embodiment 1, there are two pneumatic paper-folding vibration absorbers in one cycle. The air pressure of the first, third, fifth, seventh, and ninth paper-folding pneumatic vibration absorbers is maintained at 0.17 MPa, while the air pressure of the second, fourth, sixth, eighth, and tenth vibration absorbers gradually changes from 0.107 MPa to 0.17 MPa. The corresponding dynamic simulation results are as follows. Figure 7 As shown, when the air pressure of the vibration absorber is 0.17 MPa, the band gap is [44.75 Hz, 64.50 Hz], and the width is 19.75 Hz. As the air pressure is gradually adjusted to 0.107 MPa, the band gap changes from one to two, and the adjustable band gap range is [12.05 Hz, 64.50 Hz], with a width of 52.45 Hz. Therefore, compared to the non-adjustable case, the adjustable air pressure expands the band gap range by approximately 2.6 times.

[0049] Example 2: Control of vibration characteristics of a beam structure. In this example, only a tenth vibration absorber 11 needs to be left on the beam, such as... Figure 8 As shown. Specifically, it aims to absorb vibrations during the beam's vibration process. Once the external excitation frequency of the beam structure is determined under specific working conditions, the air pressure is adjusted according to the relationship between the natural frequency of the pneumatic origami vibration absorber and the air pressure, so that the natural frequency of all absorbers is equal to or close to the external excitation frequency, thus achieving the vibration absorption purpose. In this embodiment, the results of the dynamic simulation are as follows... Figure 9 As shown, the solid line represents the displacement transmissibility at the end of the beam without vibration absorbers under external excitation, while the rectangular points represent the displacement transmissibility under vibration absorber control. The external excitation frequency gradually increases from 11.77Hz to 46.58Hz. Through vibration absorber control, a transmissibility reduction of more than 10 times can be achieved. Specifically, near the first-order resonant frequency of the beam structure at 20.3Hz, the displacement transmissibility without vibration absorbers is 31.53. When vibration absorbers are added and the air pressure is adjusted to bring the natural frequency of the absorbers to 20.3Hz, the displacement transmissibility of the beam structure decreases to 0.05.

[0050] The purpose of this application is to design an active vibration absorber based on origami structure and pneumatics. This absorber is lightweight and has an actively adjustable natural frequency, allowing for multiple placements on beam structures. The absorber changes its overall stiffness and thus its natural frequency by altering its internal air pressure. The internal air pressure is controlled by an electromagnetic proportional valve, which can be adjusted via a host computer, enabling closed-loop control of the entire system. When the beam structure is used as the wave transmission medium, a large number of pneumatic origami-style vibration absorbers are required, and their air pressure distribution must meet periodic conditions. The corresponding bandgap structure is then calculated using the aforementioned ω(q) method, and adjusting the air pressure allows for adjustment of the bandgap structure. When the beam is used as the vibration transmission medium, the internal air pressure of the pneumatic origami-style vibration absorber is adjusted according to the frequency of the external excitation, making its natural frequency equal to or close to the external excitation frequency, thereby achieving vibration absorption.

[0051] The preferred embodiments of the present invention have been described in detail above. It should be understood that those skilled in the art can make numerous modifications and variations based on the concept of the present invention without creative effort. Therefore, all technical solutions that can be obtained by those skilled in the art based on the concept of the present invention through logical analysis, reasoning, or limited experimentation on the basis of existing technology should be within the scope of protection defined by the claims.

Claims

1. A pneumatically adjustable vibration absorber based on a paper-folding structure, hereinafter referred to as a pneumatic paper-folding vibration absorber, characterized in that, Arranged on the beam structure; specifically including a pneumatic vibration absorber with an origami structure and an electromagnetic proportional valve; wherein: The pneumatic vibration absorber of the origami structure has an acrylic plate at its bottom and a beam structure connected by bolts. The number of pneumatic vibration absorbers arranged on the beam structure is one or more; each vibration absorber is arranged at equal intervals. The pneumatic vibration absorber consists of an airbag, air tubes, a Yoshimura origami structure, bolts, studs, a counterweight block, and three circular acrylic plates, arranged in an upper, middle, and lower configuration; wherein: The airbag is cylindrical and made of PVC film. The upper end is fixed to the middle circular acrylic plate with hot melt adhesive and is fixed at the center of the middle circular acrylic plate. The lower end of the airbag is also fixed to the center of the lower circular acrylic plate with hot melt adhesive. The cylindrical airbag is perpendicular to the middle and lower acrylic plates. Bolt holes are provided on the outer sides of the upper, middle and lower circular acrylic sheets, and a circular hole is provided in the center of the lower circular acrylic sheet; One end of the air tube is connected to the lower part of the airbag through a circular hole in the center of the lower circular acrylic plate and is fixed with hot melt adhesive. The other end of the air tube is connected to the air outlet of the electromagnetic proportional valve. The electromagnetic proportional valve is controlled by the host computer to change the air pressure. The Yoshimura origami structure is made of PET film through laser cutting. Its two ends are fixed to the middle circular acrylic plate and the lower circular acrylic plate, respectively, and are all fixed with bolts. It is spatially surrounded on the outside of the cylindrical airbag. The counterweight mass block is connected and fixed by bolts and an upper acrylic plate; The upper and middle circular acrylic panels are fixed with four studs.

2. A method for controlling a pneumatically adjustable vibration absorber based on a paper-folding structure as described in claim 1, characterized in that, The specific steps are as follows: (1) The adjustable vibration absorption frequency of the pneumatic adjustable vibration absorber is calibrated, and its natural frequency under different air pressures is obtained by using a vibrator test. That is, the natural frequency of the vibration absorber and the air pressure are approximately linearly related. (2) Control of wave transmission characteristics of beam structure: For beam structure as the carrier of elastic wave transmission, the number of vibration absorbers arranged on the beam structure is greatly increased: 8-12 vibration absorbers are arranged within a unit length of meter of the beam structure. Then determine the periodic arrangement of the air pressure inside the vibration absorber. Specifically, assume that S vibration absorbers are a unit, and there are N units in total. The internal air pressure of the S vibration absorbers in the first unit is P1, P2, ..., PS. Then the internal air pressure of the M vibration absorbers in the subsequent N-1 units is arranged in the same way as in the first unit. Based on the plane wave expansion method analysis theory in the form of ω(q), the bandgap distribution corresponding to the beam structure is obtained; according to the law of the periodic arrangement of air pressure inside the vibration absorber, the air pressure inside each folded pneumatic vibration absorber is changed, thereby realizing the control of the bandgap. (3) Control of vibration characteristics of beam structure: For beam structure as the carrier of vibration transmission, it is necessary to determine the frequency of external excitation; specifically, based on the relationship between the natural frequency and air pressure of the pneumatic origami vibration absorber obtained above, the internal air pressure is adjusted to make its natural frequency equal to the external excitation frequency, thereby achieving the vibration absorption effect.

3. The control method for the pneumatically adjustable vibration absorber based on origami structure according to claim 2, characterized in that, In step (2), the control of the wave transmission characteristics of the beam structure is as follows: for the case where two pneumatic origami vibration absorbers are a unit, the air pressure of the two absorbers is different, and the air pressure of the remaining pneumatic origami vibration absorbers is arranged according to the same rule; after the absorbers are inflated, the band gap of the overall structure needs to be calculated by the plane wave expansion method in the form of ω(q). First, the stiffness matrix K and mass matrix M of the overall structure are calculated using the following formulas: Where E is the elastic modulus of the beam structure, I is the moment of inertia of the beam section, b is the beam cross-sectional width, h is the beam cross-sectional height, A is the beam cross-sectional area, a is the spacing between adjacent origami pneumatic vibration absorbers, ρ is the beam density, m is the total mass of a single vibration absorber, k1 and k2 are the stiffnesses of the first and second vibration absorbers respectively, x1 and x2 are the positions of the first and second vibration absorbers in the local coordinate system respectively, M is the stage order, q is the wave vector, and i is the imaginary unit; in formula (2), matrix q M This is a diagonal matrix. Both horizontal and vertical ellipses represent the number 0, and diagonal ellipses indicate that the diagonal elements consist of (q-2Mπ). 4 Gradually increasing to (q+2Mπ). 4 The ellipsis in (3) indicates the data vector P. j The elements in are e i[q-2Mπ / a]xj Gradually increase to e i[q +2Mπ / a]xj P j The elements in the vector are determined by e -i[q-2Mπ / a]xj Gradually reduce to e -i[q+2Mπ / a]xj In formula (4), I is the identity matrix, and both horizontal and vertical ellipses represent the number 0, while diagonal ellipses represent that all diagonal elements are 1. Finally, according to the following equation: (K-oh 2 M)X=0 (5) By solving for eigenvalues ​​and scanning the value of q sequentially, 2M+3 eigenvalue frequencies are obtained, and the corresponding band structure is obtained. The frequency range without eigenvalue solutions in the band structure diagram is the band gap range. If the air pressure value is changed, k1 and k2 in the formula will change, and the overall band gap of the structure will be adjusted.

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