A foldable satellite mast and its preparation method and application

Abstract

A foldable satellite mast and its preparation method and application belong to the field of aerospace, and the specific scheme is as follows: A foldable satellite mast includes a carbon fiber tube, which is composited with carbon fiber cloth and shape memory resin; a plurality of pairs of oblong hole gaps are provided on the carbon fiber tube, each pair has two oblong hole gaps, and are symmetrically arranged on the side wall of the carbon fiber tube, if the carbon fiber tube includes a single-layer carbon fiber cloth or a double-layer carbon fiber cloth, the angle θ between the planes where the two adjacent pairs of oblong hole gaps are located satisfies 0<θ<180, and a foldable satellite mast is obtained; if half of the side wall of the carbon fiber tube is a single-layer carbon fiber cloth, and the other half of the side wall is a double-layer carbon fiber cloth, the angle θ between the planes where the two adjacent pairs of oblong hole gaps are located satisfies θ=0 or 90°, and a foldable satellite mast is obtained. The satellite mast designed by the present invention can significantly improve the space utilization rate of spacecraft.

Description

Technical Field

[0001] The invention belongs to the field of aerospace, and in particular relates to a foldable and unfoldable satellite mast and a preparation method and application thereof. Background Art

[0002] Satellite antennas or solar panels are generally folded and stored on the side of the satellite. After entering the predetermined orbit, they are unfolded to obtain a larger area. The satellite mast is an important part of the spacecraft structure. When designing and manufacturing satellites, it is necessary to consider the material, size, strength and other parameters of the mast to ensure the stability and performance of the satellite. How to use smaller space on spacecraft where every inch of land is valuable is the direction that scientists have been working on. Satellite masts usually use lightweight, high-strength materials, such as carbon fiber composites, titanium alloys, etc., to meet the weight and strength requirements of spacecraft. Existing foldable masts are mostly curled and require a large amount of unfolding energy, which also requires the corresponding unfolding mechanism, which invisibly increases the mass and volume of the spacecraft. Summary of the invention

[0003] In order to solve the problems existing in the background technology, the present invention designs the structure of a tubular mast and cuts it according to specific positions to achieve the folding and storage of a straight tube in space. It has the ability of elastic expansion and shape memory expansion capability and can be designed according to needs.

[0004] In order to achieve the above object, the present invention adopts the following technical solutions:

[0005] A foldable satellite mast comprises a carbon fiber tube, wherein the carbon fiber tube is composited with carbon fiber cloth and shape memory resin; a plurality of pairs of oblong hole slits are provided on the carbon fiber tube, each pair has two oblong hole slits, and the oblong hole slits are symmetrically arranged on the side wall of the carbon fiber tube; if the carbon fiber tube comprises a single-layer carbon fiber cloth or a double-layer carbon fiber cloth, and the angle θ between the planes where the two adjacent pairs of oblong hole slits are located satisfies 0<θ<180, a foldable satellite mast is obtained; if half of the side wall of the carbon fiber tube is a single-layer carbon fiber cloth and the other half is a double-layer carbon fiber cloth, the angle θ between the planes where the two adjacent pairs of oblong hole slits are located satisfies 0<θ<180, and the foldable satellite mast is obtained; Carbon fiber cloth, an angle θ between the planes where two adjacent pairs of oblong hole gaps are located satisfies θ=0 or 90°, when θ=0, the planes where the two adjacent pairs of oblong hole gaps are located are the same, and are evenly distributed at the junction of the double-layer carbon fiber cloth and the single-layer carbon fiber cloth, so that a foldable and unfoldable satellite mast is obtained; when θ=90°, the planes where the two adjacent pairs of oblong hole gaps are located are vertical, among which one pair is opened at the junction of the double-layer carbon fiber cloth and the single-layer carbon fiber cloth, and the other pair is opened on the relatively arranged single-layer and double-layer carbon fiber cloth, so that a foldable and unfoldable satellite mast is obtained.

[0006] Furthermore, the shape memory resin includes one or more combinations of shape memory epoxy resin, shape memory polyurethane, shape memory polystyrene, and shape memory polyimide.

[0007] Furthermore, the semicircular diameters at both ends of the oblong hole gap are the width of the oblong hole gap, the width of the oblong hole gap is 1 / 3-2 / 3 of the diameter of the carbon fiber tube, the length of the oblong hole gap is 2-7 times the semicircular diameter, and the interval between two adjacent oblong hole gaps is greater than the diameter of the carbon fiber tube.

[0008] Further, when the carbon fiber tube includes a single-layer carbon fiber cloth or a double-layer carbon fiber cloth, θ is 30°, 60° or 90°.

[0009] A method for preparing a foldable and unfoldable satellite mast comprises the following steps:

[0010] Step 1: Select a tubular mold, wipe the surface with a release agent, and cover it with release paper;

[0011] Step 2: Calculate the required width of the carbon fiber cloth w = π × d × a, where d is the mold diameter, a is 1.1, 1.5 or 2, and the length of the carbon fiber cloth is less than the length of the mold.

[0012] Step 3: Prepare shape memory resin; lay the carbon fiber cloth flat on a piece of release paper, evenly coat the prepared shape memory resin on the carbon fiber cloth, cover it with another piece of release paper, and place it in an oven for pre-curing to obtain a prepreg cloth, which is pre-cured to the gel point;

[0013] Step 4: Take the prepreg, peel off the release paper, wrap the prepreg tightly on the mold, and solidify it by vacuum bag pressing process; demould the solidified composite material, cut the two ends neatly, and obtain a carbon fiber tube;

[0014] Step 5. When a=1.1 or 2, the corresponding carbon fiber tube includes a single-layer carbon fiber cloth or a double-layer carbon fiber cloth, and a plurality of pairs of oblong hole slits are opened on the carbon fiber tube, each pair has two oblong hole slits, which are symmetrically arranged on the side wall of the carbon fiber tube, and the angle θ between the planes where the two adjacent pairs of oblong hole slits are located satisfies 0<θ<180, that is, a foldable and unfoldable satellite mast is obtained; when a=1.5, half of the side wall of the corresponding carbon fiber tube is a single-layer carbon fiber cloth, and the other half of the side wall is a double-layer carbon fiber cloth, and a plurality of pairs of oblong hole slits are opened on the carbon fiber tube, each pair has two oblong hole slits, which are symmetrically arranged on the side wall of the carbon fiber tube, and the two adjacent pairs The angle θ between the planes where the oblong hole gaps are located satisfies θ=0 or 90°. When θ=0, the planes where the two adjacent pairs of oblong hole gaps are located are the same and are evenly distributed at the junction of the double-layer carbon fiber cloth and the single-layer carbon fiber cloth, thus obtaining a foldable and unfoldable satellite mast. When θ=90°, the planes where the two adjacent pairs of oblong hole gaps are located are vertical, wherein one pair is opened at the junction of the double-layer carbon fiber cloth and the single-layer carbon fiber cloth, and the other pair is opened on the relatively arranged single-layer and double-layer carbon fiber cloth (one oblong hole gap is opened on the single-layer carbon fiber cloth, and one oblong hole gap is opened on the double-layer carbon fiber cloth), thus obtaining a foldable and unfoldable satellite mast.

[0015] Furthermore, the tubular mold includes a metal tube or a polytetrafluoroethylene tube.

[0016] Furthermore, in step three, the content of the shape memory resin accounts for 35-70% of the total amount of the shape memory resin and the carbon fiber cloth.

[0017] An application of a foldable and unfoldable satellite mast comprises the following steps: heating the positions on both sides of an oblong hole gap to a temperature above the Tg of a shape memory resin, applying a small external force to the middle of the positions on both sides of the oblong hole gap to achieve bending and folding of the satellite mast, removing the external force when the position is cooled to room temperature, and achieving shape memory folding and fixing, heating the positions on both sides of the oblong hole gap again, and the bent end can be automatically unfolded according to its own shape memory performance; or applying a small external force to the middle of the positions on both sides of the oblong hole gap to achieve bending and folding of the satellite mast and fix it with an external force, and after removing the external force, the bent end can be automatically unfolded according to its own elastic performance.

[0018] Furthermore, the angle θ between the planes where two adjacent pairs of oblong hole gaps are located satisfies 0<θ<180, so that more forms of folding and storage methods can be realized.

[0019] Furthermore, when the angle θ between the planes where two adjacent pairs of oblong hole gaps are located is 0, the satellite mast can be bent and folded in a 'Z' shape or folded in half.

[0020] Compared with the prior art, the present invention has the following beneficial effects:

[0021] Traditional single-layer tubular structures generally only have elasticity but not shape memory. This application uses shape memory resin to make it have shape memory. The method of opening oblong holes in the present invention is not limited to parallel slits with θ=0°. The value range of θ is 0<θ<180°, so as to obtain more forms of folding and storage methods, preferably 30°, 60°, 90° and other angles, which improves space utilization compared to traditional 'z' folding.

[0022] The satellite mast prepared by the present application has both elasticity and good shape memory ability. The combination of elasticity and shape memory ability of the satellite mast prepared when a=1.5 is the best. Its asymmetric material with one side wall being double-layer carbon fiber cloth and the other side wall being single-layer carbon fiber cloth makes it have better elasticity and shape memory performance than the traditional single-layer tubular structure. The side of the satellite mast with double-layer carbon fiber cloth has greater elastic energy when bent, has greater expansion force than the traditional single-layer tubular structure, and has more resin than the single-layer tubular structure, and its shape memory performance is better than the single-layer tubular structure; when realizing the shape memory ability, the side of the satellite mast with two layers of carbon fiber cloth can provide shape memory fixation and shape memory recovery capabilities, and the single-layer side can provide elastic expansion ability, which has better fixing ability and greater expansion force than the traditional single-layer tubular structure.

[0023] The satellite mast with double-layer carbon fiber cloth has good shape memory ability, and the value range of θ is 0<θ

[0024] <180°, you can open oblong holes at angles of 30°, 60°, 90°, etc. as needed to improve space utilization. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 is a schematic diagram of the satellite mast structure prepared when a=1.5 and θ=0, where A and B are the directions of applying external forces;

[0026] Figure 2 is a physical picture of a satellite mast prepared when a=1.5 and θ=0, wherein (a) is a folded satellite mast segment, and (b) is an unfolded satellite mast segment;

[0027] Figure 3 is a schematic diagram of a satellite mast structure prepared when a=1.1, 1.5 or 2 and θ=90°;

[0028] Figure 4 is a physical unfolded diagram of a satellite mast prepared when a=1.1, 1.5 or 2 and θ=90°;

[0029] Figure 5The actual folding of the satellite mast prepared when a=1.1, 1.5 or 2 and θ=90° Figure 1 ;

[0030] Figure 6 The actual folding of the satellite mast prepared when a=1.1, 1.5 or 2 and θ=90° Figure 2 ;

[0031] Figure 7 The actual folding of the satellite mast prepared when a=1.1, 1.5 or 2 and θ=90° Figure 3 . DETAILED DESCRIPTION

[0032] The technical solution of the present invention will be clearly and completely described below in conjunction with the drawings and embodiments. Obviously, the described embodiments are only part of the embodiments of the invention, rather than all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention. Specific implementation method 1

[0034] A foldable satellite mast and a preparation method and application thereof, comprising the following steps:

[0035] (1) Select / make mold

[0036] Take a metal tube or polytetrafluoroethylene tube with a diameter of 2-6 cm as the mold, and the length is selected according to the length of the mast. Use a release agent to rub the surface 1-3 times, and after the release agent evaporates, cover it with a layer of release paper for easy demoulding.

[0037] (2) Cutting carbon fiber cloth

[0038] According to the mold with a diameter of d selected in the above steps, the width of the cut carbon fiber cloth is calculated as w = π × d × a, where a is 1.1, 1.5, and 2. If a = 1.1, the carbon fiber cloth wrapped outside the mold is a single layer. If a = 1, there is a gap at the intersection of the carbon fiber cloth outside the mold, so a = 1.1 is selected, and the 0.1 margin is used for filling the gap; if a = 1.5, the carbon fiber cloth wrapped outside the mold is double-layered in half and single-layered in the other half. If a = 2, the carbon fiber cloth wrapped outside the mold is double-layered. The length of the carbon fiber cloth should be less than the length of the mold in the above steps, such as 20-200cm.

[0039] (3) Preparation of resin

[0040] Prepare resin, such as one or more combinations of shape memory epoxy resin, shape memory polyurethane, shape memory polystyrene, and shape memory polyimide, and prepare the quality of the resin according to the glue content of 35-70% according to the quality of the carbon fiber cloth.

[0041] (4) Resin pre-curing

[0042] Cut two pieces of release paper, the size of which should be slightly larger than that of the carbon fiber cloth, lay the carbon fiber cloth flat on one piece of release paper, then evenly apply the prepared resin on the carbon fiber cloth, and cover it with another piece of release paper. Place it in an oven for pre-curing to obtain a pre-impregnated cloth. Pre-curing to the gel point.

[0043] (5) Take the pre-cured prepreg, peel off the release paper, wrap the prepreg on the mold, and wrap it tightly.

[0044] (6) Curing step: Use a porous release film to tightly cover the outer surface of the prepreg, and then cover the outer layer with a breathable mesh to absorb the overflowed resin, and then cover it with a layer of porous release film, and finally wrap it in a sealing bag. Use sealant to completely cover the mold and prepreg, open a small hole in the sealing bag at one end of the mold, put the air pipe and joint of the vacuum pump into the sealing bag, and use sealant to prevent air leakage. Finally, put it in an oven for heating and curing. While heating and curing, turn on the vacuum pump and adjust the sealing bag so that the prepreg fits tightly to the mold.

[0045] (7) Demolding the cured composite material, and cutting off the uneven parts at both ends to obtain a carbon fiber tube.

[0046] (8) When a=1.1 or 2, a plurality of pairs of oblong hole slits are provided on the carbon fiber tube, each pair has two oblong hole slits, and they are symmetrically arranged on the side wall of the carbon fiber tube, and the angle θ between the planes where two adjacent pairs of oblong hole slits are located satisfies 0<θ<180, thus obtaining a foldable and unfoldable satellite mast. Preferably, the angle θ between the planes where two adjacent pairs of oblong hole slits are located is 30°, 60° or 90°. Figure 3 and 4 When θ=90°, the satellite mast is shown in the schematic diagram and the actual picture. In specific applications, heating films are posted on both sides of the oblong hole gap, and heated to above the Tg of the shape memory resin. A small force is applied to the middle of both sides of the oblong hole gap to achieve the bending and folding of the satellite mast, such as Figure 5-7 As shown, the shape is fixed by external force, and the external force is removed when it cools to room temperature, so that shape memory folding and fixing can be achieved. The heating film is powered on for heating, and the bent end can be automatically unfolded according to its own shape memory performance. Alternatively, a small external force is applied to the middle of the two sides of the oblong hole gap to achieve the bending and folding of the satellite mast and fix it with external force. After the external force is removed, the bent end can be automatically unfolded according to its own elastic performance; the angle θ between the planes where the two adjacent pairs of oblong hole gaps are located meets 0<θ<180, which can achieve more forms of folding and storage.

[0047] When a=1.5, several pairs of oblong hole slots are opened on the carbon fiber tube, each pair has two oblong hole slots, symmetrically arranged on the side wall of the carbon fiber tube, and the angle θ between the planes where two adjacent pairs of oblong hole slots are located satisfies θ=0 or 90°. When θ=0, the planes where the two adjacent pairs of oblong hole slots are located are the same and are evenly distributed at the junction of the double-layer carbon fiber cloth and the single-layer carbon fiber cloth, thus obtaining a foldable and unfoldable satellite mast, as shown in FIG. Figure 1 As shown; when θ=90°, the planes where the two adjacent pairs of oblong hole gaps are located are vertical, among which one pair is opened at the junction of the double-layer carbon fiber cloth and the single-layer carbon fiber cloth, and the other pair is opened on the relatively arranged single-layer and double-layer carbon fiber cloth, thus obtaining a foldable and unfoldable satellite mast. In specific applications, heating films are posted on both sides of the oblong hole gaps and heated to above the Tg of the shape memory resin. A small force is applied to the middle of both sides of the oblong hole gaps to realize the bending and folding of the satellite mast, and its shape is fixed by external force. When it is cooled to room temperature, the external force is removed to realize shape memory folding and fixing. The heating film is electrically heated, and the bent end can be automatically unfolded according to its own elasticity and shape memory properties. Since the thickness of the two side walls of the carbon fiber tube is inconsistent, the tube can realize shape memory fixation and unfolding while having the ability to elastically unfold. When the angle θ between the planes where the two adjacent pairs of oblong hole gaps are located is 0, the satellite mast can be bent and folded in a 'z' shape or folded in half, as shown in FIG. Figure 2 shown.

[0048] The width of the oblong hole gap is 1 / 3-2 / 3 of the diameter of the carbon fiber tube, the semicircular diameters at both ends of the oblong hole gap are the width of the oblong hole gap, the length of the oblong hole gap is 2-7 times the semicircular diameter, the interval between two adjacent oblong hole gaps is greater than the diameter of the carbon fiber tube, and the number of the oblong hole gaps is determined according to the total length of the satellite mast and is not required.

[0049] In addition, it should be understood that although the present specification is described according to implementation modes, not every implementation mode contains only one independent technical solution. This description of the specification is only for the sake of clarity. Those skilled in the art should regard the specification as a whole. The technical solutions in each embodiment may also be appropriately combined to form other implementation modes that can be understood by those skilled in the art.

Claims

1. A foldable satellite mast, comprising a carbon fiber tube, characterized in that: The carbon fiber tube is composited with carbon fiber cloth and shape memory resin; a plurality of pairs of oblong hole slits are provided on the carbon fiber tube, each pair has two oblong hole slits, and are symmetrically arranged on the side wall of the carbon fiber tube; half of the side wall of the carbon fiber tube is a single-layer carbon fiber cloth, and the other half of the side wall is a double-layer carbon fiber cloth, and the angle θ between the planes where the two adjacent pairs of oblong hole slits are located satisfies θ=0 or 90°, when θ=0, the planes where the two adjacent pairs of oblong hole slits are located are the same, and are evenly distributed at the junction of the double-layer carbon fiber cloth and the single-layer carbon fiber cloth, thus obtaining a foldable and unfoldable satellite mast; when θ=90°, the planes where the two adjacent pairs of oblong hole slits are located are vertical, wherein one pair is provided at the junction of the double-layer carbon fiber cloth and the single-layer carbon fiber cloth, and the other pair is provided on the relatively arranged single-layer and double-layer carbon fiber cloth, thus obtaining a foldable and unfoldable satellite mast.

2. A foldable satellite mast according to claim 1, characterized in that: The shape memory resin includes one or more of shape memory epoxy resin, shape memory polyurethane, shape memory polystyrene and shape memory polyimide.

3. The foldable satellite mast according to claim 1, characterized in that: The semicircular diameters at both ends of the oblong hole gap are the width of the oblong hole gap, the width of the oblong hole gap is 1 / 3-2 / 3 of the diameter of the carbon fiber tube, the length of the oblong hole gap is 2-7 times the semicircular diameter, and the interval between two adjacent oblong hole gaps is greater than the diameter of the carbon fiber tube.

4. A method for preparing a foldable and unfoldable satellite mast according to any one of claims 1 to 3, characterized in that: The following steps are involved: Step 1: Select a tubular mold, wipe the surface with a release agent, and cover it with release paper; Step 2: Calculate the required width of the carbon fiber cloth w = π × d × a, where d is the mold diameter, a is 1.5, and the length of the carbon fiber cloth is less than the length of the mold. Step 3, preparing shape memory resin; laying the carbon fiber cloth flat on a piece of release paper, evenly coating the prepared shape memory resin on the carbon fiber cloth, covering it with another piece of release paper, and heating and pre-curing it to obtain a prepreg cloth, which is pre-cured to the gel point; Step 4: Take the prepreg, peel off the release paper, wrap the prepreg tightly on the mold, and cure it using a vacuum bag pressing process; The cured composite material is demoulded and the two ends are neatly cut to obtain a carbon fiber tube; Step 5, when a=1.5, half of the side wall of the corresponding carbon fiber tube is a single-layer carbon fiber cloth, and the other half of the side wall is a double-layer carbon fiber cloth. Several pairs of oblong hole slits are opened on the carbon fiber tube, and each pair has two oblong hole slits, which are symmetrically arranged on the side wall of the carbon fiber tube. The angle θ between the planes where the two adjacent pairs of oblong hole slits are located satisfies θ=0 or 90°. When θ=0, the planes where the two adjacent pairs of oblong hole slits are located are the same and are evenly distributed at the junction of the double-layer carbon fiber cloth and the single-layer carbon fiber cloth, so that a foldable and unfoldable satellite mast is obtained. When θ=90°, the planes where the two adjacent pairs of oblong hole slits are located are vertical, among which one pair is opened at the junction of the double-layer carbon fiber cloth and the single-layer carbon fiber cloth, and the other pair is opened on the relatively arranged single-layer and double-layer carbon fiber cloth, so that a foldable and unfoldable satellite mast is obtained.

5. The preparation method according to claim 4, characterized in that: The tubular mold comprises a metal tube or a polytetrafluoroethylene tube.

6. The preparation method according to claim 4, characterized in that: In step three, the content of the shape memory resin accounts for 35-70% of the total amount of the shape memory resin and the carbon fiber cloth.

7. An application of the foldable and unfoldable satellite mast according to any one of claims 1 to 3, characterized in that: The following steps are involved: The two sides of the oblong hole gap are heated to above the Tg of the shape memory resin, and a small external force is applied to the middle of the two sides of the oblong hole gap to achieve the bending and folding of the satellite mast. When it is cooled to room temperature, the external force is removed to achieve shape memory folding and fixation. The two sides of the oblong hole gap are heated again, and the bent end can automatically unfold according to its own shape memory performance; or a small external force is applied to the middle of the two sides of the oblong hole gap to achieve the bending and folding of the satellite mast and fix it with external force. After the external force is removed, the bent end can automatically unfold according to its own elastic performance.

8. The use according to claim 7, characterized in that: The angle θ between the planes where two adjacent pairs of oblong hole gaps are located satisfies 0<θ<180, so that more forms of folding and storage methods can be realized.

9. The use according to claim 7, characterized in that: When the angle θ between the planes where two adjacent pairs of oblong hole gaps are located is 0, the satellite mast can be bent and folded in a 'Z' shape or folded in half.

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