Space spinning type unfolding mesh antenna

Abstract

The invention provides a space spinning type unfolding mesh antenna. A truss comprises 6N telescopic vertical rods which are respectively fixed with 6N satellites which are annularly distributed; the cable net comprises a front three-way cable net fixed at one end of the 6N telescopic vertical rods and a back three-way cable net fixed at the other end of the 6N telescopic vertical rods respectively, and each node of the front three-way cable net is connected with a corresponding node in the back three-way cable net through a longitudinal cable, so that the front three-way cable net forms a paraboloid shape; and the metal reflection silk screen is attached to the front three-way cable net. The telescopic vertical rods can be longitudinally contracted, the multiple telescopic vertical rods are mutually independent, the adjacent telescopic vertical rods are flexibly connected through the cable net, the occupied space is small, the expansion and contraction ratio of the antenna can be improved, the constraint relation of strong coupling does not exist between the telescopic vertical rods, the profile precision of the antenna can be better guaranteed, and the antenna can be widely applied to the field of antenna devices. Meanwhile, the antenna structure is simplified and the assembly difficulty is reduced.

Description

Technical Field

[0001] The present invention belongs to the field of antenna technology and relates to a space-spinning unfolding mesh antenna, which can be applied to the field of aerospace. Background Art

[0002] Satellite communications, electronic reconnaissance, Earth observation, terrestrial remote sensing, deep space exploration, and radio astronomy require radio equipment to transmit data in the form of radio waves. Radio equipment uses antennas to radiate and receive signals. Reflector antennas, due to their high gain and simple structure, are widely used in these fields. With the advancement and development of space science and technology, requirements for large apertures and high precision are increasing for reflector antennas. Larger apertures mean higher signal gain, enabling the transmission of higher-resolution data and improving the signal-to-noise ratio for weak signals, enabling the completion of more scientific missions. However, due to the conflict between antenna size and mass and the carrying capacity of launch vehicles, large-aperture antennas must be lightweight and deployable. Deployable antennas can be categorized as solid reflector antennas, air-filled reflector antennas, and mesh reflector antennas. Compared to solid and air-filled reflector antennas, mesh reflector antennas offer a higher aspect ratio while maintaining high surface accuracy.

[0003] According to the different ways of deploying the supporting structure, mesh reflector antennas have derived various structural forms, the representative ones being radial rib mesh reflector antennas, frame mesh reflector antennas and ring truss mesh reflector antennas. In order to ensure that the antenna has a large aspect ratio while maintaining high surface accuracy, for example, patent application publication number CN117855801A, entitled "Ring-shaped radial rib deployable antenna structure", discloses a ring-shaped radial rib deployable mesh reflector antenna, the structure of which is as follows: Figure 1As shown, it includes an annular truss structure located on the outside and a three-fold structure located on the inside, one end of the three-fold rib structure is connected to the annular truss structure, and the other end is connected to the base located in the center of the entire antenna structure; the annular truss structure is composed of a plurality of transverse quadrilateral units connected together, and the three-fold rib structure is composed of a first section rib, a middle section rib, and a last section rib connected in sequence; a mesh parabolic metal wire mesh is connected from the bottom end of the external annular truss structure to the base, which forms a back-to-back structure with the three-fold rib structure, and each metal wire is connected to the three-fold surface cable net through a plurality of vertical adjustment cables. The invention combines the annular truss antenna with the radial rib antenna, and has the advantages of a large aspect ratio and high rigidity of the annular truss antenna, as well as the advantages of a rib antenna. The invention has the advantage of high linear precision, but since the length of the vertical rods of the multiple horizontal quadrilateral units constituting the annular truss structure of the invention is not adjustable, when the length of the vertical rods is fixed, the expanded height of the quadrilateral unit is strictly limited, and the horizontal rods connect the adjacent vertical rods to form a quadrilateral unit, so that the movement of each rod is mutually restricted, resulting in the entire structure presenting a rigid linkage of "one hair moves the whole body", making it difficult to achieve local optimization, and restricting the further expansion of the antenna aspect ratio; and the existing annular truss multi-ring closed-chain structure adopts multi-loop nesting and closed-chain constraint design, resulting in its geometric topology being highly complex, and there is a strong coupling constraint relationship between the loops, which requires the structure to meet strict geometric precision requirements during the manufacturing and assembly process, resulting in great difficulty in manufacturing and assembly. Summary of the Invention

[0004] The purpose of the present invention is to overcome the defects of the prior art and propose a space-spinning unfolded mesh antenna, which aims to expand the antenna's aspect ratio while ensuring the accuracy of the antenna surface and reduce the difficulty of assembly.

[0005] To achieve the above-mentioned purpose, the technical solution adopted by the present invention includes a truss 1, a cable net 2 and a metal reflective wire mesh 3; the truss 1 includes 6N retractable vertical poles respectively fixed to 6N satellites distributed in a ring; the cable net includes a front three-dimensional cable net 21 and a back three-dimensional cable net 22 at the other end, which are structurally connected and respectively fixed to one end of the 6N retractable vertical poles. Each node of the front three-dimensional cable net 21 is connected to the corresponding node in the back three-dimensional cable net 22 through a longitudinal cable 23, so that the front three-dimensional cable net 21 forms a parabolic shape; the metal reflective wire mesh 3 is attached to the front three-dimensional cable net 21.

[0006] As an optimization, the retractable vertical rod has a fixed part which is a hollow fixed rod 11, in which two telescopic rods 12 that can move along its central axis are nested. A circular countersunk hole is provided at the center of the embedded end of the telescopic rod 12, and elastic components 13 that provide driving force for the two opposite telescopic rods 12 are provided in the countersunk holes. A limiting device 14 is provided between the contact surface of the fixed rod 11 and the two telescopic rods 12.

[0007] As an optimization, the fixed rod 11 and the two telescopic rods 12 are all made of lightweight aluminum alloy.

[0008] As an optimization, the limiting device 14 includes an annular groove arranged on the inner surface of the fixed rod 11, and a plurality of pits arranged on the outer surface of the telescopic rod 12. Springs and balls are placed in the pits. When the two telescopic rods 12 move toward each other relative to the central axis of the fixed rod 11, the balls are locked in the annular groove of the fixed rod 11 by the elastic force of the spring.

[0009] As an optimization, the annular grooves provided on the inner surface of the fixing rod 11 are close to the two ports of the fixing rod 11 .

[0010] As an optimization, the telescopic rod 12 has a plurality of depressions provided on its outer circumferential surface, close to the end in contact with the elastic component 13 .

[0011] As an optimization, the fixed rod 11 of the telescopic vertical rod is fixed to the satellite, and the free ends of the two telescopic rods 12 are respectively fixed to the front three-way cable net 21 and the back three-way cable net 22 at the other end.

[0012] As an optimization, the front three-dimensional cable net 21 and the back three-dimensional cable net 22 both adopt a regular 6N-gon structure, and their 6N vertices are respectively fixed to the free ends of 6N telescopic rods 12.

[0013] As an optimization, the front three-way cable net 21, the back three-way cable net 22 and the longitudinal cables 23 are all made of Kevlar ropes.

[0014] Compared with the prior art, the present invention has the following advantages:

[0015] 1. The truss in the present invention includes a plurality of retractable vertical rods respectively fixed to a plurality of satellites distributed in a ring. The retractable vertical rods can be longitudinally contracted and are independent of each other. The vertices of the polygonal front three-way cable net and the back three-way cable net are respectively fixed to the free ends of the plurality of retractable vertical rods. Adjacent retractable vertical rods are flexibly connected by the cable net, which avoids the defect of the existing technology that the annular truss structure takes up a large space, and is conducive to improving the antenna's aspect ratio.

[0016] 2. The multiple telescopic vertical rods in the truss of the present invention are distributed in a ring shape and are independent of each other. There is no strong coupling constraint relationship between the telescopic vertical rods, which can better ensure the surface accuracy of the antenna, while simplifying the structure of the antenna and reducing the difficulty of assembly. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 It is a schematic diagram of the overall structure of the prior art.

[0018] Figure 2 Schematic diagram of the overall structure of an embodiment of the present invention.

[0019] Figure 3 It is a schematic diagram of the partial structure of the telescopic vertical rod of the present invention.

[0020] Figure 4 This is a schematic diagram of the principle of the spin expansion of the present invention. DETAILED DESCRIPTION

[0021] The present invention is further described in detail below with reference to the accompanying drawings and specific embodiments.

[0022] Reference Figure 2 The present invention includes a truss 1, a cable net 2 and a metal reflective wire mesh 3.

[0023] The truss 1 comprises 6N telescopic vertical rods arranged in a circular pattern and arranged longitudinally, wherein the fixed portions of the 6N telescopic vertical rods are fixed to 6N satellites respectively; the satellites serve as driving devices to provide driving force for the rotational deployment of the antenna. In this example, N=1.

[0024] The retractable vertical rod has a hollow fixed rod 11 as its fixed part, and two telescopic rods 12 that can move along its central axis are nested in the fixed rod 11. An elastic component 13 that provides driving force for the two telescopic rods 12 is provided between the two telescopic rods 12, and a limiting device 14 is provided between the fixed rod 11 and the two telescopic rods 12.

[0025] The fixing rod 11 is made of lightweight aluminum alloy material, 6151 aluminum alloy in this example. The length of the fixing rod 11 is 950 mm. Two circular holes distributed along the axis of the fixing rod are provided in the middle of the side where the fixing rod 11 is fixed to the satellite. The diameter of the circular holes is 10 mm, and the distance between the centers of the two circular holes is 20 mm. The fixing rod 11 is fixed to the satellite with bolts through the circular holes.

[0026] The two telescopic rods 12 are made of lightweight aluminum alloy, 6151 aluminum alloy in this example. Each rod 12 is 450 mm long. A circular countersunk hole with a depth of 350 mm is located at the center of the embedded end of the telescopic rod 12, which is located inside the fixed rod 11. When the two telescopic rods 12 are retracted, the retracted length of the telescopic vertical rod is 950 mm. When the two telescopic rods 12 are extended, the extended length of the telescopic vertical rod is 1600 mm.

[0027] The elastic member 13 is located in the countersunk holes of the two opposing telescopic rods 12 and is formed of a coil spring, a torsion bar spring, a gas spring, or a rubber spring. In this embodiment, a coil spring is used. When the two telescopic rods 12 are retracted, the coil spring is compressed to a length of 750 mm. When the telescopic vertical rod is extended, the coil spring is extended to a length of 1400 mm.

[0028] The limiting device 14 includes an annular groove provided on the inner surface of the fixed rod 11, which is close to the two ports of the fixed rod 11. In this example, the annular groove is 75 mm away from the port of the fixed rod 11; a plurality of pits are provided on the outer surface of the telescopic rod 12, and a spring and a ball in contact with the spring are placed at the bottom of the pit. The radius of the ball is greater than the depth of the annular groove; the depth of the plurality of pits provided on the outer surface of the telescopic rod 12 is greater than the radius of the ball. In this example, the distance between the deep pit and the end of the telescopic rod 12 close to the end in contact with the elastic component 13 is 50 mm.

[0029] When the two telescopic rods 12 move toward each other relative to the central axis of the fixed rod 11 , the balls are locked in the annular groove of the fixed rod 11 by the elastic force of the spring.

[0030] The cable net 2 can adopt a three-dimensional cable net, a radial cable net or a quasi-geodesic cable net structure similar to the ring-shaped truss mesh reflector antenna. This example adopts a three-dimensional cable net structure with better mechanical properties. After unfolding, the cable force in each cable segment is evenly distributed. The overall shape of the mesh formed by the three-dimensional cable net is a regular hexagon. As the diameter increases, in order to ensure the accuracy of the mesh, the number of connecting rods needs to be increased. In order to ensure the stability of the structure, the structure needs to be symmetrical. The added vertical rods should be symmetrically distributed on the six sides of the hexagon. Therefore, the number of retractable vertical rods should be a multiple of 6.

[0031] The cable net 2 includes a front three-dimensional cable net 21 and a back three-dimensional cable net 22, which are structurally interconnected and respectively fixed at one end of 6N telescopic vertical rods. Each node of the front three-dimensional cable net 21 is connected to the corresponding node in the back three-dimensional cable net 22 through a longitudinal cable 23, so that the front three-dimensional cable net 21 forms a parabolic shape; the front three-dimensional cable net 21, the back three-dimensional cable net 22 and the longitudinal cable 23 are all made of Kevlar rope; in this example, the antenna diameter is 5000mm and the focal length is 1250mm. After the net is unfolded, the distance between the fixed points of the front three-dimensional cable net 21 and the back three-dimensional cable net 22 on the same telescopic vertical rod is 1600mm, which is the same as the length of the telescopic vertical rod after it is unfolded.

[0032] The metal reflective wire mesh 3 is fixed on the front three-way cable net 21 so as to be parabolic in shape and is used to reflect radio waves.

[0033] The present invention's spin-type expansion includes the process from folding to expansion, accelerated rotation and uniform rotation. The principle is as follows: Figure 4 As shown:

[0034] Reference Figure 4 (a) When 6N satellites are distributed in a ring around the central axis of the antenna, the antenna is in a retracted state. At this time, the two telescopic rods 12 are retracted in the fixed rod 11, and at the same time, the cable net 2 is retracted. There is no interaction force between the cable net 2 in a relaxed state and the telescopic vertical rod.

[0035] Reference Figure 4 (b) When 6N satellites move away from the central axis of the antenna and the retractable vertical rods extend until the cable net 2 is tightened, the antenna is in the deployed state. At this time, the balls are locked in the annular groove of the fixed rod 11 by the elastic force of the spring. At this time, the cable net 2 is in the tightened state. The retractable vertical rods provide horizontal tension to the net surface. After the length of the retractable vertical rods is fixed, it provides vertical tension to the net surface.

[0036] Reference Figure 4 (c) When 6N satellites perform uniformly accelerated circular motion around the central axis of the antenna, the antenna is in an accelerated rotation state. At this time, the cable net 2 is in a taut state. The centripetal force generated by the rotation of the retractable vertical rod driven by the satellite provides lateral tension for the net surface. The retractable vertical rod is fixed in length and provides vertical tension for the net surface.

[0037] Reference Figure 4 (d) When 6N satellites make uniform circular motion around the central axis of the antenna, the antenna is in a uniform rotation state. At this time, the cable net 2 is in a taut state. The centripetal force generated by the rotation of the retractable vertical rod driven by the satellite is the horizontal tension of the net surface. The length of the retractable vertical rod is fixed, providing vertical tension for the net surface.

Claims

1. A space-spinning unfolded mesh antenna, comprising a truss (1), a cable net (2) and a metal reflective wire mesh (3); characterized in that: The truss (1) comprises 6N telescopic vertical rods respectively fixed to 6N satellites distributed in a ring; the cable net comprises a front three-dimensional cable net (21) and a back three-dimensional cable net (22) respectively fixed to one end of the 6N telescopic vertical rods, which are structurally connected and fixed to the other end of the 6N telescopic vertical rods; each node of the front three-dimensional cable net (21) is connected to a corresponding node in the back three-dimensional cable net (22) through a longitudinal cable (23), so that the front three-dimensional cable net (21) forms a parabola; the metal reflective wire mesh (3) is attached to the front three-dimensional cable net (21).

2. The antenna according to claim 1, wherein: The spin-type deployment includes a folded state, an unfolded state, an accelerated rotation state and a uniform rotation state; when 6N satellites are distributed in a ring around the central axis of the antenna, the antenna is in a folded state; when 6N satellites move away from the central axis of the antenna and the retractable vertical rod is extended until the cable net 2 is tightened, the antenna is in an unfolded state; when 6N satellites make uniform accelerated circular motion around the central axis of the antenna, the antenna is in an accelerated rotation state; when 6N satellites make uniform circular motion around the central axis of the antenna, the antenna is in a uniform rotation state.

3. The antenna according to claim 1, wherein: The telescopic vertical rod has a fixed portion which is a hollow fixed rod (11). Two circular holes distributed along the axis of the fixed rod (11) are provided in the middle of one side where the fixed rod (11) is fixed to the satellite. The fixed rod (11) is fixed to the satellite via the circular holes using bolts. Two telescopic rods (12) movable along the central axis are nested in the fixed rod (11). A circular countersunk hole is provided at the center of the embedded end of the telescopic rod (12). Elastic components (13) for providing driving force to the two opposite telescopic rods (12) are provided in the countersunk holes. A limiting device (14) is provided between the contact surfaces of the fixed rod (11) and the two telescopic rods (12).

4. The antenna according to claim 3, wherein: The fixed rod (11) and the two telescopic rods (12) are all made of lightweight aluminum alloy.

5. The antenna according to claim 3, wherein: The limiting device (14) comprises an annular groove provided on the inner surface of the fixed rod (11) and a plurality of sinks provided on the outer surface of the telescopic rod (12). Springs and balls are placed in the sinks. When the two telescopic rods (12) move toward each other relative to the central axis of the fixed rod (11), the balls are locked in the annular groove of the fixed rod (11) by the elastic force of the springs.

6. The antenna according to claim 5, wherein: The fixing rod (11) has an annular groove provided on its inner surface, close to the two ends of the fixing rod (11).

7. The antenna according to claim 5, wherein: The telescopic rod (12) has a plurality of sink holes arranged on its outer surface, close to the end in contact with the elastic component (13).

8. The antenna according to claim 3, wherein: The fixed rod (11) of the telescopic vertical rod is fixed to the satellite, and the free ends of the two telescopic rods (12) are respectively fixed to the front three-way cable net (21) and the back three-way cable net (22) at the other end.

9. The antenna according to claim 8, wherein: The front three-dimensional cable net (21) and the back three-dimensional cable net (22) both adopt a regular 6N-polygon structure, and their 6N vertices are respectively fixed to the free ends of 6N telescopic rods (12).

10. The antenna according to claim 1, wherein: The front three-dimensional cable net (21), the back three-dimensional cable net (22) and the longitudinal cable (23) are all made of Kevlar ropes.

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