Six-degree-of-freedom vibration isolation platform based on Miura paper folding type structure

Abstract

The invention relates to a six-degree-of-freedom vibration isolation platform based on a Miura paper folding type structure, and belongs to the technical field of vibration isolation platforms, the six-degree-of-freedom vibration isolation platform comprises a plurality of vibration isolation supporting legs, each vibration isolation supporting leg comprises a lower flat plate, an upper flat plate, a guide strip, a sliding rail, a sliding block, a supporting plate, an upper paper folding piece and a lower paper folding piece, and the lower flat plates are fixed to a lower platform; the upper flat plate is positioned above the lower flat plate; the bottom ends of the guide strips are fixed on the lower flat plate and the top ends are fixed on the upper flat plate; the slide rail is fixed on the guide strip; the sliding block slides on the sliding block; the supporting plate is fixed on the sliding block; the top end of the upper paper folding piece is fixed to the upper flat plate, and the bottom end rotates on the supporting plate. The top end of the lower paper folding piece rotates on the supporting plate, and the bottom end is fixed to the lower flat plate. The upper paper folding piece and the lower paper folding piece are connected in the gaps among the upper flat plate, the lower flat plate and the supporting plate at intervals in the vertical line direction, and negative stiffness can be linearly expressed in a wider range when folding telescopic movement is conducted from one stable state to another stable state in the vertical direction.

Description

Technical Field

[0001] The invention relates to the technical field of vibration isolation platforms, and in particular to a six-degree-of-freedom vibration isolation platform based on a Miura origami structure. Background Art

[0002] In aerospace engineering, vibrations can cause harmonic interference, which can seriously affect the stability and performance of satellite internal structures, such as space optomechanical systems. It is critical to effectively isolate low-frequency micro-vibrations on spacecraft to avoid interference with system performance. Usually, isolators or vibration isolation materials are set between the optomechanical system and the satellite structure to isolate the disturbances generated by the vibration source. However, if the vibration of the interference source cannot be effectively isolated, it may lead to unclear observation results and even affect the success of the mission.

[0003] The design theory of the classic linear vibration isolator has certain limitations. First, when the frequency of the vibration source is greater than When the natural frequency of the vibration isolation layer is equal to 1, the force / displacement transmission rate is less than 1, and the vibration can be effectively isolated at this time. However, as the aperture and focal length of the spatial optical-mechanical system continue to increase, its absolute stiffness is low, making it impossible to effectively isolate low-bandwidth micro-vibrations. Secondly, increasing the damping coefficient can reduce the vibration amplitude in the low-frequency resonance band and accelerate the attenuation of transient vibrations under high dynamic conditions. However, the increase in linear damping will deteriorate the isolation performance within the original effective vibration isolation band and induce micro-vibrations containing more complex resonant frequency components. Therefore, the linear vibration isolation layer design theory cannot meet the requirements for flutter suppression of spatial high-dynamic optical-mechanical systems.

[0004] In response to the demand for low-bandwidth vibration isolation of space optomechanical systems under complex interference, scholars have proposed various multi-DOF Stewart-type vibration isolators design methods, which can achieve high static and low dynamic vibration isolation effects and adapt to different dynamic environments. However, nonlinear vibration isolators for space system needs must have a lightweight and compact design, and there are relatively few studies on multi-DOF configurations that are more suitable for actual working conditions. In particular, the demand for the application of six-DOF vibration isolation in engineering is growing. Therefore, the development of a lightweight, quasi-zero stiffness multi-DOF vibration isolation platform has become an urgent task for scientific researchers and technicians.

[0005] Origami has been widely used in the field of engineering technology in recent years. Origami structures have unique mechanical properties of nonlinear stiffness deformation, which can effectively achieve low-bandwidth vibration isolation. The unconventional mechanical properties of origami, such as deformation, variable stiffness, and variable size, provide new possibilities for low-bandwidth vibration isolation design.

[0006] Therefore, inventing a multi-degree-of-freedom nonlinear passive vibration isolation platform with advantages such as designability, lightweight, and structural motion decoupling to meet the needs of fundamental frequency vibration suppression and isolation of spatial high-dynamic optomechanical systems will bring important technological breakthroughs and huge application value to this field. Summary of the invention

[0007] The present invention provides a six-degree-of-freedom vibration isolation platform based on a Miura origami structure, thereby obtaining a more excellent vibration isolation performance and greater adjustability of structural design parameters in multiple degrees of freedom directions, and realizing a lightweight and compact design of the vibration isolation platform.

[0008] To achieve the above-mentioned purpose, the technical solution of the present invention is: a six-degree-of-freedom vibration isolation platform based on a Miura origami structure, comprising a lower platform connected to a vibration isolation object, an upper platform connected to a vibration source, a plurality of connecting parts and a plurality of vibration isolation legs, wherein the upper platform is located parallel to and above the lower platform; the plurality of connecting parts are spaced apart along the circumference of the upper platform and the top ends thereof are all fixed on the upper platform; the plurality of vibration isolation legs are spaced apart along the circumference of the lower platform and the bottom ends thereof are all fixed on the lower platform; the bottom ends of the plurality of connecting parts are respectively fixed on the plurality of vibration isolation legs; the plurality of vibration isolation legs each comprise a lower plate, an upper plate, a guide bar, a slide rail, a slider, a support plate, an upper origami piece and a lower origami piece,

[0009] The lower plate is fixed parallel to the lower platform; the upper plate is located above the lower plate in parallel; the guide bar is arranged along the vertical direction of the lower platform and its bottom end is fixed on the lower plate, and its top end is fixed on the upper plate; the slide rail is fixed on the guide bar along the length direction of the guide bar; the slider slides on the slide rail; the support plate is fixed on the slider; the top end of the upper folding paper piece is fixed to the upper plate by bolts and the bottom end of the upper folding paper piece is rotated on the support plate by a screw rod and a bearing; the top end of the lower folding paper piece is rotated on the support plate by a screw rod and a bearing and the bottom end is fixed to the lower plate by bolts; the bottom ends of multiple connecting members are respectively fixed to the corresponding support plates.

[0010] The beneficial effects of the present invention are as follows: first, the upper origami piece and the lower origami piece are connected in the gap between the upper flat plate, the lower flat plate and the support plate at intervals along the vertical direction, so that when the folding and telescopic movement is performed vertically from one stable steady state to another stable steady state, the negative stiffness is linearly expressed in a wider range; and then the support plate is fixed on the slider. Since the slider slides on the slide rail, the sliding stability of the support plate can be maintained to prevent the support plate from shaking.

[0011] Furthermore, the multiple connecting parts all include a universal joint, a connecting rod, a ball joint and a ball joint connecting part, the universal joint is fixed on the upper platform; the top end of the connecting rod is hinged on the universal joint; the ball joint is hinged on the bottom end of the connecting rod; the ball joint connecting part is fixed on the ball joint and fixed on the corresponding support plate.

[0012] Furthermore, each of the plurality of vibration isolation legs further comprises a spring, the top end of the spring being fixed on the upper plate and the bottom end of the spring being fixed on the sliding block.

[0013] A further beneficial effect of the above arrangement is that the top end of the spring is fixed on the upper plate and the bottom end is fixed on the slider. Since the slider slides on the slide rail and the slide rail is fixed on the guide bar, each vibration isolation leg is constructed with absolutely zero stiffness within a certain interval, thereby achieving large amplitude and ultra-low frequency isolation characteristics, and expanding the applicability of the vibration isolator to low-frequency and large-amplitude excitation in actual engineering.

[0014] Furthermore, the plurality of connecting rods are all made of lightweight materials.

[0015] Furthermore, the upper origami component and the lower origami component have the same structure and are both Miura origami structures.

[0016] Furthermore, the Miura origami structure is formed by connecting the common edges of Miura origami unit I and Miura origami unit II, and both Miura origami unit I and Miura origami unit II are composed of four rigid origami that intersect at one point through four elastic folds.

[0017] A further beneficial effect of the above is that the parallel symmetrical stacking assembly design of Miura origami unit I and Miura origami unit II constitutes a linear performance of negative stiffness in a wider range, thereby obtaining a wider quasi-zero stiffness performance range.

[0018] Furthermore, the initial folding angle γ of the Miura origami unit I is A The initial folding angle γ of the Miura origami unit II is 30-60°. B The initial state angle θ of the Miura origami structure is 30 to 60°. A It is 30~60°.

[0019] The above further beneficial effects are: the parallel symmetrical stacking assembly design of Miura origami unit I and Miura origami unit II exhibits a bistable characteristic, presenting two folding configurations, namely, an inset and an outward convex configuration. By adjusting the key structural parameters including the initial folding angle γ of Miura origami unit I and Miura origami unit II, A , γ B and the initial state angle θ of the Miura origami structure A It will affect the overall size of the Miura origami structure, and its changes show the changing law of the negative stiffness segment of the structure.

[0020] Furthermore, the Miura origami unit I and the Miura origami unit II are both integrally formed and have an empty groove in the middle.

[0021] A further beneficial effect of the above is that Miura origami unit I and Miura origami unit II use 3D printing technology to produce an integrated origami frame in order to better reflect the integrated characteristics, durability and sustainable use of the origami structure.

[0022] Furthermore, the area of ​​the lower platform is larger than the area of ​​the upper platform.

[0023] The beneficial effects of the present invention are:

[0024] 1. Compared with the prior art, the present invention provides a quasi-zero stiffness passive vibration isolation design for a six-degree-of-freedom vibration isolation platform of a Miura origami structure. The advantages of this configuration design are that it can achieve structural motion decoupling in the z direction of space; increase structural stiffness; and the vibration isolation legs adopt a motion arrangement of parallel guide rails to achieve high-precision vibration isolation effects.

[0025] 2. A new designable nonlinear origami stacking assembly structure is introduced as the vibration isolation leg to replace the legs of the traditional Stewart platform. The origami structure can flexibly adjust the stiffness, expand the vibration isolation frequency band, and at the same time ensure the lightweight design of the platform with a certain load-bearing capacity, which is more in line with the lightweight and compact design requirements in aerospace missions.

[0026] 3. The structure of the multi-degree-of-freedom origami vibration isolation platform of the present invention is simple and flexible, which is conducive to the simple adjustment of structural parameters to achieve a variety of required load-bearing capacities and vibration isolation performances. For example, by adjusting the initial assembly angle of the guide rod, the upper and lower platform radii, the origami design angle and other parameters, the static and dynamic stiffness of the vibration isolation platform can be changed, thereby achieving free regulation of the mechanical properties. Therefore, the vibration isolation platform has a vibration isolation effect with adjustable mechanical properties, and can be suitable for multi-directional low-frequency vibration isolation under complex and changeable working conditions.

[0027] 4. The proposed vibration isolation platform is a passive vibration isolation platform, which does not require external energy consumption. For traditional vibration isolators, active control is required to achieve effective vibration isolation in the low-frequency range, which requires external energy consumption. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 It is a three-dimensional structural schematic diagram of a six-degree-of-freedom vibration isolation platform based on a Miura origami structure of the present invention;

[0029] Figure 2 It is a schematic diagram of the three-dimensional structure of a vibration isolation leg in a six-degree-of-freedom vibration isolation platform based on a Miura origami structure of the present invention;

[0030] Figure 3 It is a schematic diagram of the forming demonstration of the Miura origami structure in a six-degree-of-freedom vibration isolation platform based on the Miura origami structure of the present invention.

[0031] In the accompanying drawings, the components represented by each mark are listed as follows:

[0032] 1. Lower platform, 2. Upper platform, 3. Connecting part, 31. Universal hinge, 32. Connecting rod, 33. Ball joint, 34. Ball joint connecting part, 4. Vibration isolation leg, 41. Lower plate, 42. Upper plate, 43. Guide strip, 44. Slide rail, 45. Slider, 46. Support plate, 47. Upper origami part, 48. Lower origami part, 49. Spring, 410. Miura origami unit I, 411. Miura origami unit II. DETAILED DESCRIPTION

[0033] The principles and features of the present invention are described below in conjunction with the accompanying drawings. The examples given are only used to explain the present invention and are not used to limit the scope of the present invention.

[0034] like Figure 1 and Figure 2 As shown, a six-degree-of-freedom vibration isolation platform based on a Miura origami structure includes a lower platform 1, an upper platform 2, a plurality of connecting members 3 and a plurality of vibration isolation legs 4, wherein the upper platform 2 is located above the lower platform 1 in parallel; the plurality of connecting members 3 are distributed at intervals along the circumference of the upper platform 2 and the top ends thereof are all fixed on the upper platform 2; the plurality of vibration isolation legs 4 are distributed at intervals along the circumference of the lower platform 1 and the bottom ends thereof are all fixed on the lower platform 1; the bottom ends of the plurality of connecting members 3 are respectively fixed on the plurality of vibration isolation legs 4; the plurality of vibration isolation legs 4 each include a lower plate 41, an upper plate 42, a guide bar 43, a slide rail 44, a slider 45, a support plate 46, an upper origami member 47 and a lower origami member 48,

[0035] The lower plate 41 is fixed on the lower platform 1 in parallel; the upper plate 42 is located above the lower plate 41 in parallel; the guide bar 43 is arranged along the vertical direction of the lower platform 1 and its bottom end is fixed on the lower plate 41, and its top end is fixed on the upper plate 42; the slide rail 44 is fixed on the guide bar 43 along the length direction of the guide bar 43; the slider 45 slides on the slide rail 44; the support plate 46 is fixed on the slider 45; the top end of the upper folding paper piece 47 is fixed to the upper plate 42 by bolts and the bottom end thereof is rotated on the support plate 46 by a screw rod and a bearing; the top end of the lower folding paper piece 48 is rotated on the support plate 46 by a screw rod and a bearing and the bottom end thereof is fixed to the lower plate 41 by bolts; the bottom ends of multiple connecting members 3 are respectively fixed on the corresponding support plates 46.

[0036] like Figure 1 and Figure 2 As shown, in some specific embodiments, the plurality of vibration isolation legs 4 may further include a spring 49 , the top end of the spring 49 is fixed on the upper plate 42 and the bottom end of the spring 49 is fixed on the slider 45 .

[0037] like Figure 1 and Figure 2As shown, in some specific embodiments, multiple connecting parts 3 can include a universal joint 31, a connecting rod 32, a ball joint 33 and a ball joint connecting part 34, the universal joint 31 is fixed on the upper platform 2; the top end of the connecting rod 32 is hinged on the universal joint 31; the ball joint 33 is hinged on the bottom end of the connecting rod 32; the ball joint connecting part 34 is fixed on the ball joint 33 and fixed on the corresponding support plate 46.

[0038] Specifically, the plurality of connecting rods 32 are all made of lightweight materials.

[0039] Specifically, the upper origami member 47 and the lower origami member 48 have the same structure and are both Miura origami structures.

[0040] like Figure 3 As shown, in some specific embodiments, the Miura origami structure is formed by connecting the common edges of Miura origami unit I410 and Miura origami unit II411, and both Miura origami unit I410 and Miura origami unit II411 are composed of four rigid origami that intersect at one point through four elastic folds.

[0041] like Figure 3 As shown, in some specific embodiments, the initial folding angle γ of the Miura origami unit I410 A The initial folding angle γ of Miura origami unit II411 is 30-60° B The initial state angle θ of the Miura origami structure is 30-60°. A It is 30~60°.

[0042] Specifically, Miura origami unit I410 and Miura origami unit II411 are both integrally formed and have empty grooves in the middle.

[0043] Specifically, the area of ​​the lower platform 1 is larger than the area of ​​the upper platform 2 .

[0044] The above are only preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A six-degree-of-freedom vibration isolation platform based on a Miura origami structure, comprising a lower platform (1), an upper platform (2), a plurality of connecting members (3) and a plurality of vibration isolation legs (4), wherein the upper platform (2) is located above the lower platform (1) in parallel; the plurality of connecting members (3) are spaced apart along the circumference of the upper platform (2) and their top ends are all fixed on the upper platform (2); the plurality of vibration isolation legs (4) are spaced apart along the circumference of the lower platform (1) and their bottom ends are all fixed on the lower platform (1); the bottom ends of the plurality of connecting members (3) are respectively fixed on the plurality of vibration isolation legs (4); characterized in that: The plurality of vibration isolation legs (4) each comprises a lower plate (41), an upper plate (42), a guide bar (43), a slide rail (44), a slider (45), a support plate (46), an upper folding paper piece (47) and a lower folding paper piece (48). The lower plate (41) is fixed in parallel to the lower platform (1); the upper plate (42) is located above the lower plate (41) in parallel; the guide bar (43) is arranged along the vertical direction of the lower platform (1) and its bottom end is fixed on the lower plate (41), and its top end is fixed on the upper plate (42); the slide rail (44) is fixed on the guide bar (43) along the length direction of the guide bar (43); the slider (45) slides on the slide rail (44); the support plate (46) is fixed on the slider (45); the top end of the upper folding paper piece (47) is fixed to the upper plate (42) by bolts and the bottom end thereof is rotated on the support plate (46) by a screw rod and a bearing; the top end of the lower folding paper piece (48) is rotated on the support plate (46) by a screw rod and a bearing and the bottom end thereof is fixed to the lower plate (41) by bolts; the bottom ends of the plurality of connecting members (3) are respectively fixed on the corresponding support plates (46).

2. A six-degree-of-freedom vibration isolation platform based on a Miura origami structure according to claim 1, characterized in that: The plurality of vibration isolation legs (4) also include a spring (49), the top end of the spring (49) being fixed on the upper plate (42) and the bottom end of the spring (49) being fixed on the slider (45).

3. The six-degree-of-freedom vibration isolation platform based on the Miura origami structure according to claim 1, characterized in that: The plurality of connecting members (3) each include a universal joint (31), a connecting rod (32), a ball joint (33) and a ball joint connecting member (34); the universal joint (31) is fixed on the upper platform (2); the top end of the connecting rod (32) is hinged on the universal joint (31); the ball joint (33) is hinged on the bottom end of the connecting rod (32); and the ball joint connecting member (34) is fixed on the ball joint (33) and fixed on the corresponding support plate (46).

4. The six-degree-of-freedom vibration isolation platform based on the Miura origami structure according to claim 3, characterized in that: The plurality of connecting rods (32) are all made of lightweight materials.

5. The six-degree-of-freedom vibration isolation platform based on the Miura origami structure according to claim 1, characterized in that: The upper origami piece (47) and the lower origami piece (48) have the same structure and are both Miura origami structures.

6. The six-degree-of-freedom vibration isolation platform based on the Miura origami structure according to claim 5, characterized in that: The Miura origami structure is formed by connecting the common edges of Miura origami unit I (410) and Miura origami unit II (411), and both Miura origami unit I (410) and Miura origami unit II (411) are composed of four rigid origami that intersect at one point through four elastic folds.

7. The six-degree-of-freedom vibration isolation platform based on the Miura origami structure according to claim 6, characterized in that: The initial folding angle γ of the Miura origami unit I (410) A The initial folding angle γ of the Miura origami unit II (411) is 30-60°. B The initial state angle θ of the Miura origami structure is 30 to 60°. A It is 30~60°.

8. The six-degree-of-freedom vibration isolation platform based on the Miura origami structure according to claim 6, characterized in that: The Miura origami unit I (410) and the Miura origami unit II (411) are both integrally formed and have a hollow groove in the middle.

9. The six-degree-of-freedom vibration isolation platform based on the Miura origami structure according to claim 1, characterized in that: The area of ​​the lower platform (1) is greater than the area of ​​the upper platform (2).

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