CN110085965B

CN110085965B - Deployable satellite antenna of cable membrane integrated configuration

Info

Publication number: CN110085965B
Application number: CN201910335729.7A
Authority: CN
Inventors: 何柏岩; 焦彪彪
Original assignee: Tianjin University
Current assignee: Tianjin University
Priority date: 2019-04-24
Filing date: 2019-04-24
Publication date: 2020-10-30
Anticipated expiration: 2039-04-24
Also published as: CN110085965A

Abstract

The invention discloses an expandable satellite antenna with a cable-membrane combined structure, which consists of an annular truss on the outer side and a cable-membrane combined structure inside. The annular truss is a foldable structure formed by movable joints and rod pieces, a plurality of pneumatic rods are arranged in an annular array in the structure, and the annular truss is unfolded by parallel driving of an air supply system. The flexible cable membrane combined structure formed by a reflecting membrane, a membrane net, a longitudinal cable and a rear net surface is connected in the cylindrical space inside the annular truss, the flexible structure is unfolded after the truss is unfolded, the membrane net diffuses the concentrated acting force of the longitudinal cable at the lower edge into an even force field inside the membrane by utilizing the elastic deformation of the membrane net, so that the upper edge of the membrane net forms a required parabola, and the reflecting membrane is attached to the upper edge of the membrane net to form a continuous curved surface to fit a rotating paraboloid. The invention utilizes the curve net surface on the upper edge of the membrane net to fit the revolution paraboloid, thereby greatly improving the design precision compared with the prior straight line fitting technology.

Description

Deployable satellite antenna of cable membrane integrated configuration

Technical Field

The present invention relates to satellite antennas, and more particularly to deployable satellite antennas.

Background

With the development of aerospace technology, a large-aperture antenna is demanded in many scientific application fields, and the purpose of the antenna is to acquire a signal with small transmission power. Communication satellites, relay satellites, military reconnaissance satellites and space attack and defense microwave weapons all need antennas with the caliber of more than ten meters, the caliber of a long-baseline interferometer required by the radio astronomy subject is also more than ten meters, and a giant antenna with the caliber of more than one hundred meters is also required for the solar power station satellite to transmit high-energy microwaves to the earth; on the other hand, the carrying weight and capacity of the rocket launch capsules are quite limited; this requires that the satellite antenna must be lightweight, large-bore, deployable, and highly accurate.

All countries in the world pay high attention to the problem and obtain a plurality of corresponding achievements. Compared with other expandable antenna forms, the annular truss expandable antenna has the characteristic that the weight increase of the antenna is relatively small along with the increase of the aperture, so that the annular truss expandable antenna is an ideal form for large satellite antennas at present.

The cable net structure of the annular space-out frame type antenna mainly comprises a front cable net, a rear cable net and a longitudinal adjusting cable. The metal reflecting surface net is sewn on the front cable net reflecting surface cable net to complete the electric wave reflecting task. In order to improve the design precision of the antenna, the existing method is to increase the grid density of the front cable net; the nodes of the cable network are increased, and the probability that the cable network is mutually wound and cannot be normally unfolded in the process of unfolding the antenna in the space is greatly increased. In order to keep the accuracy of the cable net reflecting surface better, the cable net structure should also have a certain prestress to make the rigidity of the cable net structure reach a preset index. The larger the prestress is, the better the rigidity of the cable net antenna structure is, but the larger the requirement on the unfolding driving force of the antenna structure is, and the power of the satellite antenna driving motor is limited, so that the unfolding of the antenna structure is difficult or impossible.

Disclosure of Invention

The invention aims to overcome the defects of the prior art and provide the deployable satellite antenna with the cable-membrane combined structure, which improves the design precision of the antenna on the premise of not increasing the grid density.

The deployable satellite antenna of the cable membrane combined structure comprises an annular cylindrical truss, wherein the truss comprises a plurality of pneumatic rods arranged in the vertical direction, the pneumatic rods are uniformly arranged at intervals in the circumferential direction of the truss, each pneumatic rod comprises a pneumatic rod shell, a piston capable of sliding up and down along the inner wall of the pneumatic rod shell is arranged in the pneumatic rod shell, a cavity in the pneumatic rod shell at the upper part of the piston is a second cavity, and a cavity in the pneumatic rod shell at the lower part of the piston is a third cavity;

a hollow slide bar is arranged on the top wall of the piston, a middle cavity of the hollow slide bar is a first cavity, the hollow slide bar extends out of the top of the air rod shell, and a side hole is formed in the side wall of the bottom of the hollow slide bar; a sealing cover comprises a main body with a cavity in the middle, a shaft shoulder is arranged on the outer wall of the main body along the circumferential direction, the main body which is sleeved outside a hollow slide rod and is below the shaft shoulder is inserted into a second cavity of an air rod shell and is in threaded connection with the inner wall of the air rod shell at the second cavity, the shaft shoulder is tightly pressed on the top wall of the air rod shell, the hollow slide rod can slide up and down along the inner wall of the middle cavity of the main body, a locking ring which can be in up-and-down sliding connection with the main body is sleeved on the outer wall of the upper part of the main body, a spring is sleeved on the main body between the locking ring and the shaft shoulder, the upper end of the spring is in contact with the bottom wall of the locking ring, the lower end of the spring is in contact with the top wall of the shaft shoulder, two radial holes are symmetrically arranged on the outer wall of the upper part of the main body of the sealing cover along the, a circle of arc-shaped circular ring groove is formed in the outer wall of the hollow slide rod along the radial direction of the hollow slide rod along the circumferential direction, and when the arc-shaped circular ring groove is located below the position of the steel ball, the steel ball is limited in a space formed by the circular groove with the larger diameter of the locking ring, the radial hole of the main body and the cylindrical outer wall of the hollow slide rod; when the arc-shaped circular ring groove is positioned at the position of the steel ball, the two steel balls are positioned in a space formed by the circular ring groove with smaller diameter of the locking ring, the radial hole of the main body and the arc-shaped circular ring groove, and the two steel balls are respectively embedded into the arc-shaped circular ring groove on the hollow slide bar to be matched with and lock the hollow slide bar to move; an air hole communicated with a second air nozzle is formed in the outer wall of the lower part of the air rod shell at the position corresponding to the third cavity, an air hole communicated with the first air nozzle is formed in the wall of the upper part of the hollow slide rod, the first cavity is communicated with the second cavity between the hollow slide rod and the upper part of the piston through a side hole, the upper part of the hollow slide rod is connected with the thread of the synchronous hinge, and the lower part of the air rod shell is connected with a reserved interface of the locking hinge through a thread;

the film net is arranged at the upper part in the truss, the upper edge of the film net forms a parabolic net structure fitting a rotating parabolic shape under the action of the tensile force of the connecting piece when the film net is unfolded, the film net is a space grid structure formed by a plurality of elastic film pieces in a crossed mode, each grid of the film net is in a triangular hollow prism shape, the top edge of each grid is a parabola when the film net is in a completely opened state, and the two film pieces forming the same grid at the edge of the film net are connected through a connector;

the bottom in the truss is provided with a rear net surface, the rear net surface is of a triangular grid structure formed by a plurality of inhaul cables, and the two inhaul cables forming the same grid at the edge of the rear net surface are connected through a connector;

the connector comprises a hollow connecting pipe, the axis of the hollow connecting pipe is arranged along the horizontal direction, a boss is arranged on the side wall of the hollow connecting pipe along the horizontal direction, bearings are respectively fixed on the boss along the vertical direction, a pull lug is fixed on the outer ring of each bearing, a reinforcing ring is fixed on the outer edge of each membrane, the connection point of the outer edges of the two membranes of the same grid, which are fixed with the reinforcing rings, is respectively and fixedly connected with the two pull lugs of the connector in a one-to-one correspondence manner, and the connection point of the outer edges of the two pull cables of the same grid is respectively and fixedly connected with the two pull lugs of the connector in a one-to-one correspondence manner;

a reflecting film matched with the shape of the top wall of the film net is fixed on the top wall of the film net, and each grid surface of the film net is parallel to a rotating shaft of a paraboloid of revolution fitted by the unfolded film net;

each upper connector is sleeved on a cross rod on one upper part and is fixedly bonded between the two cross rods, two ends of each upper cross rod are respectively arranged between the two synchronous hinges and are hinged with the two synchronous hinges, a plurality of upper cross rods are connected with each other through the synchronous hinges to form a closed structure, each lower connector is sleeved on a lower cross rod, two ends of each lower cross rod are respectively arranged between the two locking hinges and are hinged with the two locking hinges, a plurality of cross rods are connected with each other through the locking hinges to form a closed structure, and an inclined rod is connected between two adjacent hollow slide rods along an inclined direction, one end of the inclined rod is hinged with the synchronous hinge of one hollow slide rod of the two hollow slide rods, the other end of the inclined rod is hinged with the locking hinge of the other hollow slide rod of the two hollow slide rods, and all the inclined rods are arranged in a W shape;

an annular upper air guide pipe is arranged in the cavities of the cross bars at the upper parts, an annular lower air guide pipe is arranged in the cavities of the cross bars at the lower parts, the annular upper air guide pipe and the annular lower air guide pipe are made of flexible materials, the annular upper air guide pipe is communicated with a first air nozzle of each pneumatic rod through a plurality of branch pipes, the annular lower air guide pipe is communicated with each second air nozzle through a plurality of branch pipes, the annular upper air guide pipe and the annular lower air guide pipe are respectively communicated with an air storage tank through pipelines provided with an electromagnetic throttle valve and a pressure sensor, the two air storage tanks are respectively connected with a pump port of a bidirectional pump through pipelines, and a pump shaft of the bidirectional pump is connected with a motor;

the utility model discloses a membrane net, including the membrane net, the node of the back wire side is provided with the locating platform, the locating platform is provided with in the threaded sleeve's of upper portion lower extreme respectively, the locating platform is provided with in the threaded sleeve's of lower part lower extreme respectively, the vertical direction setting of connecting piece along vertical direction, every connecting piece includes hollow stud, the upper and lower both ends of hollow stud respectively threaded connection have a threaded sleeve, threaded sleeve's upper and lower end on upper portion respectively, respectively sliding connection has a cavity slide pin in every threaded sleeve, cavity slide pin can press fit through the location shoulder of one end and locating platform, the bonding is fixed with a vertical cable in every cavity slide pin, the vertical cable of every connecting piece upper end is fixed continuous with the node of the crossing node of membrane net bottom surface department and the vertical cable of lower extreme is fixed continuous with the node of.

The invention has the beneficial effects that:

1. the net-shaped structure formed by connecting elastic films is adopted to replace a front net surface, and the characteristic of continuous elastic deformation of the net-shaped structure of the films under the action of multipoint concentration force is utilized to enable the edges of the films to form curves to fit parabolas; the metal film attached to the front net surface of the film net structure is divided into a plurality of space triangles with three parabolic sides, and the space triangles fit the parabolic surface, so that the purpose of improving the design precision of the antenna on the premise of not increasing the grid density is finally achieved.

2. Due to the special cable membrane combined structure in the invention, in the process of folding and assembling the cable membrane combined structure in the carrier rocket, the connecting nodes formed by the rear net surface and the longitudinal cables can be placed in the space of the triangular prism of the film net structure for folding and assembling, the nodes are isolated from each other by utilizing the membrane, the problem that the antenna cannot be unfolded due to mutual winding of the cables and the cables in the transportation process is prevented, and the failure rate of the antenna in space unfolding can be effectively reduced.

3. The invention provides a novel expandable truss, which improves the transmission characteristic of an antenna in the expansion process. The parallel pneumatic driving mode is adopted, the truss has the driving unfolding force far greater than the thrust of the pneumatic rod in the later half of the unfolding process, so that enough pre-tightening force is provided for the cable-membrane combined structure, and the integral rigidity of the antenna is greatly improved. After the antenna is completely unfolded and is in a stable working state, the acting force of the joint on the pneumatic rod is very small, the strength requirement of the truss pneumatic rod locking mechanism is reduced, and the stability of the whole structure is further improved.

Drawings

FIG. 1-1 is a schematic structural view of a deployable satellite antenna with a cable-membrane composite structure according to the present invention;

FIGS. 1-2 are front views of the structure shown in FIGS. 1-1;

FIG. 2 is an exploded schematic view of the structure shown in FIG. 1-1;

FIG. 3-1 is a front view of a cord membrane structure of the structure shown in FIG. 1-1;

FIG. 3-2 is a perspective view of the structure shown in FIG. 1-1;

FIG. 4 is a schematic view of the formation of the upper edge of a strip-shaped elastic film in the film web in the structure shown in FIG. 1-1;

FIG. 5 is a schematic view of the formation of edge web-side spatial triangular elements on the film web in the configuration shown in FIG. 1-1;

FIG. 6 is a schematic diagram illustrating the principle of parabolic reflector shaping in the configuration of FIG. 1-1;

FIG. 7-1 is a schematic view of the end structure of the diaphragm in the structure shown in FIG. 1-1;

FIG. 7-2 is a schematic view of the connector structure shown in FIG. 1-1;

FIG. 8-1 is a schematic view of a connector of the structure shown in FIG. 1-1;

FIG. 8-2 is a schematic view of a portion of the connector shown in FIG. 8-1 at location A;

FIG. 9 is a schematic view of the deployable truss structure of the structure shown in FIGS. 1-1;

FIG. 10 is a schematic view of the parallel driving principle of the truss pneumatic rods according to the present invention;

FIG. 11 is a schematic layout of the pneumatic truss drive system of the present invention;

FIG. 12-1 is an expanded view of a triangular truss folding unit of the present invention;

FIG. 12-2 is a schematic view illustrating the unfolding process of the triangular truss folding unit according to the present invention;

fig. 12-3 are schematic views showing folding of the triangular truss folding units of the present invention;

FIG. 13 is a schematic view of the folding and unfolding principle of the expandable truss of the present invention;

FIG. 14-1 is a schematic view of a pneumatic rod according to the present invention;

FIG. 14-2 is a partial schematic view of the pneumatic lever locking mechanism of the present invention;

FIG. 14-3 is a schematic view, partially in cross-section, B-B of the pneumatic lever locking mechanism of FIG. 14-2 after locking;

FIG. 14-4 is a schematic partial cross-sectional view B-B of the pneumatic lever locking mechanism shown in FIG. 14-2 prior to locking.

Detailed Description

The present invention is described in terms of specific embodiments, and other advantages and benefits of the present invention will become apparent to those skilled in the art from the disclosure herein.

Referring to the drawings, the structures, ratios, sizes, and the like shown in the drawings are only used for matching with the disclosure of the specification, so as to be understood and read by those skilled in the art, and are not used to limit the practical limit conditions of the present invention, so that the present invention has no technical significance, and any structural modification, ratio relationship change or size adjustment should still fall within the scope of the present invention without affecting the efficacy and the achievable purpose of the present invention. Meanwhile, the positional limitation terms used in the present specification are for clarity of description only, and are not intended to limit the scope of the present invention, and changes or modifications of the relative relationship therebetween may be regarded as the scope of the present invention without substantial changes in the technical content.

As shown in the accompanying drawings, the deployable satellite antenna with a cable-membrane combined structure comprises a circular cylindrical truss 5 in a circular cylindrical folded state and a completely deployed state, wherein the truss 5 comprises a plurality of pneumatic rods 14 arranged in a vertical direction, the pneumatic rods 14 are uniformly arranged at intervals in the circumferential direction of the truss 5, each pneumatic rod 14 comprises a pneumatic rod shell 21, a piston capable of sliding up and down along the inner wall of the pneumatic rod shell 21 is installed in the pneumatic rod shell 21, a cavity in the pneumatic rod shell 21 at the upper part of the piston is a second cavity, and a cavity in the pneumatic rod shell 21 at the lower part of the piston is a third cavity.

A hollow slide bar 17 is arranged on the top wall of the piston, a middle cavity of the hollow slide bar 17 is a first cavity 24, the hollow slide bar 17 extends out of the top of the air bar shell 21, and a side hole 26 is formed in the side wall of the bottom of the hollow slide bar 17; a sealing cover 20 comprises a main body with a cavity in the middle, a shaft shoulder is arranged on the outer wall of the main body along the circumferential direction, the main body is sleeved outside the hollow slide rod 17 in a ring mode, the part of the main body below the shaft shoulder is inserted into the second cavity of the air rod shell 21, and the main body is in threaded connection with the inner wall of the air rod shell 21 in the second cavity. The shaft shoulder is pressed and arranged on the top wall of the air rod shell 21. The hollow slide bar 17 can slide up and down along the inner wall of the middle cavity of the main body, a lock ring 18 which can be connected with the main body in a vertical sliding mode is sleeved on the outer wall of the upper portion of the main body, a spring 19 is sleeved on the main body between the lock ring 18 and the shaft shoulder, the upper end of the spring 19 is in contact with the bottom wall of the lock ring 18, the lower end of the spring is in contact with the top wall of the shaft shoulder, and the spring is in a compressed state, so that the lock ring always tends to move upwards. The outer wall of the upper part of the main body of the sealing cover 20 is symmetrically provided with two radial holes along the radial direction of the main body, the inner cavity of the locking ring 18 is provided with a secondary annular groove of which the diameter is changed from large to small from top to bottom and the diameter is transited between the two through a chamfer, the outer wall of the hollow slide bar 17 along the radial direction of the hollow slide bar 17 is provided with a circle of arc-shaped annular groove along the circumferential direction, and when the arc-shaped annular groove is positioned below the position of the steel ball, the steel ball 25 is limited in a space formed by the annular groove with the larger diameter of the locking ring 18, the radial holes of the; when the arc-shaped circular ring groove is positioned at the position of the steel ball 25, the locking ring 18 moves upwards under the pushing of the spring 19 to push the two steel balls 25 into the arc-shaped circular ring groove, at the moment, the two steel balls 25 are positioned in a space formed by the annular groove with the smaller diameter of the locking ring 18, the radial hole of the main body and the arc-shaped circular ring groove, and the two steel balls 25 are respectively embedded into the arc-shaped circular ring groove on the hollow slide rod 17 to be matched with the locking hollow slide rod 17 to move; the diameter of the steel ball 25 is larger than the sum of the depth of the arc-shaped circular groove and the wall thickness of the main body of the sealing cover 20, and a part of the steel ball 25 is arranged outside the cylindrical surface of the main body in a protruding mode to limit the locking ring 18 to move upwards continuously.

An air hole communicated with the second air nozzle 22 is formed on the outer wall of the lower part of the air rod shell 21 at the position corresponding to the third cavity 28, an air hole communicated with the first air nozzle 16 is formed on the wall of the upper part of the hollow slide rod, and the first cavity is communicated with a second cavity 27 between the hollow slide rod 17 and the upper part of the piston through a side hole.

The upper part of the hollow slide bar 17 is in threaded connection with the synchronous hinge 12, so that the assembly of the locking ring 18, the spring 19 and the sealing cover 20 is facilitated, a threaded interface is reserved at the lower end of the synchronous hinge 12 to be matched with the air rod shell, the air rod shell is bonded and fixed by using sealing glue after assembly, the lower part of the air rod shell is in threaded connection with the interface reserved by the locking hinge 23, and the structures of the synchronous hinge 12 and the locking hinge 23 respectively adopt the internal mechanical unfolding principle and structure of the synchronous hinge and the locking hinge designed in the structural design and research of ' annular expandable large satellite antenna ' of northwest university of industry [ D ]. 2001 ' pages 53-59.

Two ends of the pneumatic rod 14 are respectively assembled with the synchronous hinge 12 and the locking hinge 23 through thread pairs to form fixed fit, so that power and limit are provided for unfolding of the truss 5; the driving principle is as shown in fig. 14-1, and the length change and the thrust output of the pneumatic rod 14 are realized by controlling the gas pressure in the second cavity 27 and the third cavity 28, and further generating a pressure difference at two ends of a piston of the hollow slide rod 17 assembled in the gas rod shell 21 to drive the hollow slide rod 17 to move in the cavity of the gas rod shell 21.

After the truss 5 is unfolded to the working state, the freedom degree of the truss needs to be limited, so that the truss 5 is in the stable working state, and therefore, a displacement locking device is designed in the middle of the pneumatic rod 14, as shown in fig. 14-3 and 14-4. The hollow slide bar 17 can slide axially along the inner cavity of the sealing cover 20; the locking ring 18 is matched with the outer cylindrical surface of the sealing cover 20 through a cylindrical pair, and a spring 19 is arranged between the locking ring 18 and the sealing cover 20, so that the locking ring 18 has the tendency of sliding axially along the cylindrical surface; a secondary annular groove with different diameters and transitional through a chamfer is designed in the inner cavity of the locking ring 18 and is used for pushing and extruding the steel ball 25; the steel ball 25 is arranged in a radial hole at the tail end of the sealing cover 20 and is used for matching with an arc-shaped circular groove on the hollow slide bar 17 to lock the hollow slide bar 17 to move.

The initial free driving state is as shown in fig. 14-4, due to the extrusion of the cylindrical outer wall of the hollow slide bar 17, the steel ball is limited in the space formed by the annular cavity with larger diameter of the locking ring 18 and the radial hole at the end of the sealing cover 20, and the hollow slide bar 17 in the pneumatic rod 14 can move freely; when the arc-shaped circular groove on the hollow slide rod 17 reaches the position of the steel ball 25, the locking ring 18 slides axially under the pushing of the spring 19, so that the steel ball 25 is forced to move inwards to be embedded into the arc-shaped circular groove on the hollow slide rod 17, then the locking ring 18 continues to slide under the pushing of the spring 19 to reach the position shown in fig. 14-3, the inner wall of the annular cavity with the smaller diameter of the locking ring 18 is used for limiting the outward movement of the steel ball 25, and the pneumatic rod 14 is locked.

A membrane net 2 sets up the upper portion in truss 5, membrane net 2 when expanding the tensile effect of connecting piece down the top edge form the rotatory paraboloid shape of parabola net network structure fitting, membrane net 2 for have certain elastic membrane piece can adopt the thin film material alternately setting up formation with the same wire weaving of reflectance coating 1 by the multichannel, every net of membrane net 2 is triangle hollow prism shape, the topside of every net is the parabola under the membrane net 2 complete opening state, 2 edges of membrane net constitute the two membranes of same net and link to each other through a connector 6.

The bottom in the truss 5 is provided with a rear net surface 4, as shown in fig. 6, the rear net surface 4 is a triangular mesh structure formed by a plurality of inhaul cables. The two inhaul cables forming the same grid at the edge of the rear net surface 4 are connected through a connector 6.

The connector 6 comprises a hollow connecting pipe, the axis of the hollow connecting pipe is arranged in the horizontal direction, a boss is arranged on the side wall of the hollow connecting pipe in the horizontal direction, a bearing is respectively fixed on the boss in the vertical direction, a pull lug 7 is fixed on the outer ring of each bearing, as shown in figure 7-1, a reinforcing ring 8 is fixed on the outer edge of each membrane 2-1, as shown in figure 7-2, the connecting point of the outer edges of the two membranes 2-1 of the same grid, which are fixed with the reinforcing rings 8, is respectively and fixedly connected with the two pull lugs of the connector 6 in a one-to-one correspondence manner, and the connecting point of the outer edges of the two inhaul cables of the same grid is respectively and fixedly connected with the two pull lugs of the connector 6 in a one-to-one correspondence manner.

The connection points of the outer annular distribution of the upper edge of the membrane net 2 are connected with the cross bars 13 of the truss 5 through universal hinge mechanisms formed by the connectors 6 and the pull lugs 7 as shown in the attached figure 7-2, the connectors 6 are fixedly connected with the cross bars 13 by using adhesives, and reinforcing rings are designed at the connection points of the membrane net 2 and the connectors for improving the stress distribution in the membrane tensioning process and reducing the friction force in the hinges during mutual rotation.

The connection point of the outer edges of the two inhaul cables of the same grid is connected with the cross rod 13 of the truss 5 through a universal hinge mechanism formed by the connector 6 and the pull lug 7, and the connection point is mainly used for providing pulling force for the longitudinal inhaul cable 3. As shown in fig. 7-2, the universal hinge mechanism formed by the connector 6 and the pull tab 7 has a certain mechanical self-adaptive performance, and can effectively reduce the stress of the antenna film network 2 and the rear network surface 4 in the folding and unfolding processes.

A reflecting film 1 matched with the shape of the top wall of the film net 2 can be adhered and fixed on the top wall of the film net 2, the reflecting film 1 is an existing product, can be purchased, is of a thin film structure woven by metal materials, is attached to the edge of the upper side of the film net 2 to form an approximate rotating parabolic curved surface, and the reflecting film 1 and the film net 2 form the shape under the action of the longitudinal inhaul cables 3 to reflect microwaves. Each grid surface of the membrane web 2 is parallel to the axis of rotation of the paraboloid of revolution to which the expanded membrane web is fitted.

Each upper connector 6 is sleeved on one upper cross rod 13 and is fixedly bonded between the upper cross rods, and two ends of each upper cross rod 13 are respectively arranged between two synchronous hinges and are hinged with the two synchronous hinges. The cross bars on the upper parts are connected with each other through synchronous hinges to form a closed structure. Each lower connector 6 is sleeved on a lower cross rod 13, and two ends of each lower cross rod 13 are respectively arranged between the two locking hinges and are hinged with the two locking hinges. The cross bars are connected with each other through locking hinges to form a closed structure. An inclined rod 15 is obliquely connected between two adjacent hollow slide bars 17, one end of the inclined rod 15 is hinged with a synchronous hinge of one hollow slide bar 17 of the two hollow slide bars 17, the other end of the inclined rod 15 is hinged with a locking hinge of the other hollow slide bar 17 of the two hollow slide bars 17, and all the inclined rods are arranged in a W shape. The synchronous hinge 12 and the locking hinge 23 provide a hinge movable interface for the cross rod 13 and the inclined rod 15, and the terminal of the interface corresponding to the cross rod 13 inside the synchronous hinge can be synchronously unfolded at equal angles through a gear pair.

An annular upper duct 30 is mounted in the internal cavity of the upper cross bars 13 and an annular lower duct 29 is mounted in the internal cavity of the lower cross bars 13. The annular upper air duct 30 and the annular lower air duct 29 are made of flexible materials. The annular upper air duct 30 is communicated with the first air nozzle 16 of each pneumatic rod 14 through a plurality of branch pipes, and the annular lower air duct 29 is communicated with each second air nozzle 22 through a plurality of branch pipes. The annular upper air guide pipe 30 and the annular lower air guide pipe 29 are respectively communicated with an air storage tank through pipelines provided with an electromagnetic throttle valve and a pressure sensor, the two air storage tanks are respectively connected with a pump port of a bidirectional pump through pipelines, and a pump shaft of the bidirectional pump is connected with a motor. When the device is used, the gas storage tank and the like are arranged on a transfer arm connected with the satellite and the antenna.

The driving system assembled in the truss 5 adopts a mode of driving a plurality of pneumatic rods 14 in parallel as shown in fig. 11, and the annular upper air duct 30 and the annular lower air duct 29 are respectively communicated with the first air nozzles 16 and the second air nozzles 22 of the plurality of pneumatic rods 14 in the truss 5 through a tee joint to form a parallel driving structure. The driving principle is shown in fig. 10, when the pneumatic system composed of the air storage tank, the pump, the electromagnetic throttle valve and the pressure sensor controls the air pressure and the air flow rate in the annular upper air duct 30 and the annular lower air duct 29 to be slow enough, the pressure loss in the pipeline can be ignored, and the synchronous driving of the plurality of pneumatic rods 14 can be realized.

The folding triangular units and the integral mechanism of the truss are gradually unfolded from an initial folding state under the driving of the pneumatic rod 14, as shown in fig. 13, in the unfolding process, along with the continuous increase of the angle between the cross rods 13, the component force of the pneumatic rod 14 applied to the axial direction of the cross rods is also continuously increased, and the driving unfolding force far greater than the thrust of the pneumatic rod can be generated between the cross rods 13 in the latter half stage of the unfolding process, so that a sufficient pre-tightening force is provided for the cable-membrane combined structure, and the integral rigidity of the antenna is greatly improved. When the cross bar 13 reaches the position, the pneumatic rod 14 is automatically locked to enable the antenna to be in a stable working state; due to the self-locking design of the unfolding unit, the cross rods are in a mutual end extrusion self-locking state, the acting force of the joint on the pneumatic rod 14 is very small and almost zero, the strength requirement of the truss 5 on the locking mechanism of the pneumatic rod 14 is reduced, and the stability of the whole structure is further improved.

A connecting piece is respectively arranged between the multi-channel membrane crossing nodes of the membrane net 2 and the nodes of the rear net surface 4 in a one-to-one correspondence way, the connecting pieces are arranged along the vertical direction, as shown in fig. 5, each connecting member comprises a hollow stud 11, the upper end and the lower end of the hollow stud 11 are respectively in threaded connection with a threaded sleeve 10, a positioning table is respectively arranged in the upper end of the upper threaded sleeve 10 and the lower end of the lower threaded sleeve 10, a hollow sliding pin 9 is respectively connected in each threaded sleeve 10 in a sliding way, the hollow sliding pin 9 can be in press fit with the positioning table through a positioning shaft shoulder at one end, a longitudinal guy cable 3 is fixedly bonded in each hollow sliding pin 9, the longitudinal guy cable 3 at the upper end of each connecting piece is fixedly connected with the crossed node at the bottom surface of the membrane net 2, and the longitudinal guy cable 3 at the lower end is fixedly connected with the node of the rear net surface 4.

Two ends of a longitudinal inhaul cable 3 are respectively connected with the membrane net 2 and the rear net surface; the main function of the device is to provide longitudinal tension for the membrane net 2; in order to reduce the influence of manufacturing errors on the antenna shape accuracy; the longitudinal inhaul cable 3 is fixedly connected inside the cavity of the hollow sliding pin 9 through bonding materials, the hollow sliding pin 9 is matched with the threaded sleeve 10 through a cylindrical pair and a plane pair, the longitudinal displacement restriction is realized, the relative rotation can be realized, and unnecessary torque is prevented from being applied to the longitudinal inhaul cable 3 in the adjusting process; the length of the threaded sleeve 10 and the hollow stud 11 is adjusted through threaded matching, so that the length of the inhaul cable is adjusted, and the purpose of adjusting the pulling force is finally achieved.

Due to the special cable membrane combined structure in the carrier rocket, the connecting nodes formed by the rear net surface 4 and the connecting pieces can be placed in the triangular prism space of the membrane net 2 for folding assembly in the process of folding assembly in the carrier rocket, the nodes are isolated from each other by utilizing the membrane net, and the problem that the antenna cannot be unfolded due to mutual winding of the cable net due to vibration in the transportation process is prevented.

When a satellite needs to be launched, firstly, the antenna is folded into the minimum space and assembled inside the carrier rocket; the method comprises the following specific steps:

firstly, assembling the truss 5, and assembling the cross rod 13, the pneumatic rod 14 and the inclined rod 15 with the synchronous hinge 12 and the locking hinge 23 according to the attached drawings 9-14-1 to form the complete truss 5. The annular upper air duct 30 and the annular lower air duct are assembled in a cylindrical cavity inside the cross bar 13 in the assembling process; the connector is fixedly positioned with the cross bar 13 before assembly.

Assembling a cable membrane combined structure, sewing and bonding membrane structures according to a figure 3-2 to form a membrane net 2, and enabling each surface of the membrane structure to be parallel to a rotating shaft of a rotating paraboloid formed by the reflecting membrane in an unfolded state; the longitudinal guy cable 3 is fixedly connected in the hollow cavity of the hollow sliding pin 9 through bonding materials, and a length regulator is assembled according to the figure 8-1; the lower edge position of the intersection of the films is connected with the longitudinal guy cable 3 in a bonding mode; a reinforcing ring is arranged at the joint of the membrane net 2 and the connector hinge for improving the stress distribution in the membrane tensioning process and reducing the friction force in the hinge; and connecting the other end of the longitudinal inhaul cable 3 with the node of the rear net surface 4 to form a cable membrane combined structure.

Mounting and precision adjustment of the reflecting film, assembling the cable film combined structure on the truss 5 through a universal hinge mechanism, and driving the truss 5 to unfold; the lower edge of the film net 2 moves to one side departing from the reflective film 1 under the pulling force of the longitudinal guy cables 3, the concentrated force of the longitudinal guy cables 3 acting on the lower edge is diffused in the film by utilizing the coordinated deformability of the film net 2 structure, and more uniform tensile stress distribution is formed near the upper edge, so that the upper edge of the film net 2 forms a net surface consisting of continuous curves; the tension of each longitudinal cable is adjusted by adjusting the length adjuster on the longitudinal cable 3, so that the precision of the upper edge of the membrane net 2 forming a net surface consisting of continuous curves is adjusted, and the design requirement is met; attaching a thin film structure reflecting surface 1 woven by metal materials to the upper edge-shaped net surface of a film net 2, and bonding and fixing by using an elastic adhesive; the tension of each longitudinal cable is adjusted by adjusting the length adjuster on the longitudinal cable 3, and the precision of the reflecting surface 1 is adjusted to meet the design requirement; and then the length regulator is solidified by using an adhesive, so that the length of the reflector 1 is prevented from being changed due to vibration in the transportation process, and the forming precision of the reflector 1 after the antenna is unfolded is prevented from being influenced.

Folding and assembling, namely pressing down the locking ring of the pneumatic rod 14 to unlock the locking ring; the pneumatic rods 14 are synchronously contracted to the minimum space folding positions 12-1, 12-2, 12-3 and 13 under the control of the air pressure in the annular upper air guide pipe 30 and the annular lower air guide pipe 29 through an air bottle, an electromagnetic valve and a pressure sensor, in the folding process, connecting nodes formed by the rear net surface 4 and the longitudinal guy cables 3 are placed in the space of the triangular prism of the membrane net 2 for folding assembly, the nodes are isolated from each other by utilizing the membrane net, and the problem that the antenna cannot be unfolded due to mutual winding of vibration in the transportation process of the cable net is avoided; the truss 5 is then assembled to the satellite with a small radial prestress and the launch vehicle is loaded.

Space expansion, when the satellite is conveyed to the running orbit, the radial prestress constraint of the antenna is removed, and small-amplitude expansion is realized primarily by utilizing the resilience of the truss 5; the pneumatic system consisting of the gas storage tank, the pump, the electromagnetic throttle valve and the pressure sensor controls the air pressure in the annular upper air duct 30 and the annular lower air duct to realize the synchronous driving of the driving pneumatic rod 14, so that the truss 5 drives the cable-membrane combined structure to be unfolded and formed; when the truss 5 is unfolded to the working position, namely the cross rod 13 reaches the position, the pneumatic rod 14 is automatically locked, so that the antenna is in a stable working state; due to the self-locking design of the unfolding unit, the transverse rods are in a mutual end extrusion self-locking state, the acting force of the joints on the pneumatic rods 14 is small and almost zero, the strength requirement of the locking mechanism of the pneumatic rods 14 of the truss 5 is reduced, and the stability of the whole structure is further improved.

In the unfolding process, if the cable nets are mutually wound or wound with other parts of the satellite to cause that the cable nets cannot be unfolded, the truss 5 can be driven by the pneumatic system to be folded and unfolded for multiple times to enable the cable nets to vibrate and be separated from each other, so that the purpose of getting rid of the winding state and eliminating faults is achieved.

Claims

1. The utility model provides a but cable membrane integrated configuration expansion satellite antenna, includes ring cylinder truss (5), its characterized in that: the truss comprises a plurality of pneumatic rods (14) arranged in the vertical direction, the pneumatic rods are uniformly arranged at intervals in the circumferential direction of the truss, each pneumatic rod comprises a pneumatic rod shell (21), a piston capable of sliding up and down along the inner wall of the pneumatic rod shell is installed in the pneumatic rod shell, a cavity in the pneumatic rod shell at the upper part of the piston is a second cavity, and a cavity in the pneumatic rod shell at the lower part of the piston is a third cavity;

a hollow slide bar (17) is arranged on the top wall of the piston, a middle cavity of the hollow slide bar is a first cavity (24), the hollow slide bar extends out of the top of the air bar shell (21), and a side hole (26) is formed in the side wall of the bottom of the hollow slide bar; a sealing cover (20) comprises a main body with a cavity in the middle, a shaft shoulder is arranged on the outer wall of the main body along the circumferential direction, the main body which is sleeved outside a hollow slide rod and is below the shaft shoulder is inserted into a second cavity of an air rod shell and is in threaded connection with the inner wall of the air rod shell at the second cavity, the shaft shoulder is tightly pressed on the top wall of the air rod shell, the hollow slide rod can slide up and down along the inner wall of the middle cavity of the main body, a locking ring (18) which can be in up-and-down sliding connection with the main body is sleeved on the outer wall of the upper part of the main body, a spring (19) is sleeved on the main body between the locking ring and the shaft shoulder, the upper end of the spring is in contact with the bottom wall of the locking ring and the lower end of the spring is in contact with the top wall of the shaft shoulder, two radial holes are symmetrically formed on the outer wall of the upper part of the main body of the sealing cover (20), a circle of arc-shaped circular ring grooves are formed in the outer wall of the hollow slide rod along the radial direction of the hollow slide rod along the circumferential direction, and when the arc-shaped circular ring grooves are located below the positions of the steel balls, the steel balls (25) are limited in a space formed by the circular grooves with larger diameters of the locking rings, the radial holes of the main body and the cylindrical outer wall of the hollow slide rod (17); when the arc-shaped circular ring grooves are positioned at the positions of the steel balls (25), the two steel balls (25) are positioned in a space formed by the annular groove with the smaller diameter of the locking ring (18), the radial hole of the main body and the arc-shaped circular ring grooves, and the two steel balls (25) are respectively embedded into the arc-shaped circular ring grooves on the hollow slide rod to be matched with and lock the hollow slide rod to move; an air hole communicated with the second air nozzle is formed in the outer wall of the lower portion of the air rod shell at the position corresponding to the third cavity (28), an air hole communicated with the first air nozzle (16) is formed in the wall of the upper portion of the hollow sliding rod, the first cavity is communicated with a second cavity (27) located between the hollow sliding rod (17) and the upper portion of the piston through a side hole, the upper portion of the hollow sliding rod is connected with the thread of the synchronous hinge (12), and the lower portion of the air rod shell is connected with a reserved connector of the locking hinge (23) through threads;

the membrane net (2) is arranged at the upper part in the truss (5), the upper edge of the membrane net forms a parabolic net structure fitting a rotating parabolic shape under the action of the tensile force of a connecting piece when the membrane net is unfolded, the membrane net is a space grid structure formed by a plurality of elastic membrane pieces in a crossed mode, each grid of the membrane net is in a triangular hollow prism shape, the top edge of each grid is a parabola when the membrane net is in a completely opened state, and two membrane pieces forming the same grid at the edge of the membrane net are connected through a connector (6);

a rear net surface (4) is arranged at the bottom in the truss (5), the rear net surface is of a triangular grid structure formed by a plurality of inhaul cables, and two inhaul cables forming the same grid at the edge of the rear net surface are connected through a connector;

the connector comprises a hollow connecting pipe, the axis of the hollow connecting pipe is arranged along the horizontal direction, a boss is arranged on the side wall of the hollow connecting pipe along the horizontal direction, bearings are respectively fixed on the boss along the vertical direction, a pull lug (7) is fixed on the outer ring of each bearing, a reinforcing ring (8) is fixed on the outer edge of each membrane (2-1), the connecting points of the outer edges of the two membranes of the same grid, which are fixed with the reinforcing rings, are respectively and fixedly connected with the two pull lugs of the connector in a one-to-one correspondence manner, and the connecting points of the outer edges of the two inhaul cables of the same grid are respectively and fixedly connected with the two pull lugs of the connector in a one-to-one correspondence manner;

a reflecting film (1) matched with the top wall of the film net (2) in shape is fixed on the top wall of the film net (2), and each grid surface of the film net (2) is parallel to the rotating shaft of a paraboloid fitted by the unfolded film net;

the connector (6) on each upper portion is sleeved on a transverse rod (13) on one upper portion and fixedly bonded between the two transverse rods, two ends of the transverse rod (13) on each upper portion are respectively arranged between two synchronous hinges and are hinged with the two synchronous hinges, the transverse rods on the upper portions are mutually connected through the synchronous hinges to form a closed structure, the connector (6) on each lower portion is sleeved on the transverse rod (13) on the lower portion, two ends of the transverse rod (13) on each lower portion are respectively arranged between two locking hinges and are hinged with the two locking hinges, the transverse rods are mutually connected through the locking hinges to form a closed structure, an inclined rod (15) is obliquely connected between the two adjacent hollow sliding rods (17), one end of the inclined rod (15) is hinged with the synchronous hinge of one hollow sliding rod (17) of the two hollow sliding rods (17) and the other end of the inclined rod is hinged with the locking hinge of the other hollow sliding rod (17) of the two hollow sliding The inclined rods are connected with each other, and all the inclined rods are arranged in a W shape;

an annular upper air duct (30) is arranged in the inner cavities of cross bars (13) at the upper parts, an annular lower air duct (29) is arranged in the inner cavities of the cross bars (13) at the lower parts, the annular upper air duct (30) and the annular lower air duct (29) are made of flexible materials, the annular upper air duct (30) is communicated with a first air nozzle (16) of each pneumatic rod (14) through a plurality of branch pipes, the annular lower air duct (29) is communicated with each second air nozzle (22) through a plurality of branch pipes, the annular upper air duct (30) and the annular lower air duct (29) are respectively communicated with an air storage tank through pipelines provided with an electromagnetic throttle valve and a pressure sensor, the two air storage tanks are respectively connected with a pump port of a bidirectional pump through pipelines, and a pump shaft of the bidirectional pump is connected with a motor;

a connecting piece is respectively arranged between the plurality of membrane sheet cross nodes of the membrane net and the nodes of the back net surface in a one-to-one correspondence way, the connecting pieces are arranged along the vertical direction, each connecting piece comprises a hollow stud (11), the upper end and the lower end of each hollow stud are respectively in threaded connection with a threaded sleeve, positioning tables are respectively arranged in the upper end of the upper threaded sleeve and the lower end of the lower threaded sleeve, a hollow sliding pin (9) is respectively connected in each threaded sleeve (10) in a sliding way, the hollow sliding pin can be in press fit with the positioning table through a positioning shaft shoulder at one end, a longitudinal guy cable (3) is fixedly bonded in each hollow sliding pin, the longitudinal guy cable (3) at the upper end of each connecting piece is fixedly connected with the intersection node of the bottom surface of the membrane net (2), and the longitudinal guy cable (3) at the lower end is fixedly connected with the node of the rear net surface.