A bidirectional unfolding and folding modular parabolic cylinder antenna space deployable mechanism

Abstract

The application provides a bidirectional unfolding and folding modular parabolic cylindrical antenna space deployable mechanism, which comprises a plurality of movably connected module units, each of which is in a double "sun" shape structure with a plurality of movement joint assemblies as nodes, main rib assemblies and folding rod assemblies as transverse connecting members and longitudinal connecting members respectively, one movement locking device is arranged between each of the three commonly used movement joint assemblies in the double "sun" shape structure and the main rib assemblies connected on the two sides, and movement auxiliary devices are arranged between the two movement joint assemblies connected on the two sides of the main rib assemblies. The space occupied by the solid parts in the application is small, the volume of the antenna after folding can be reduced, the surface accuracy of the parabolic cylindrical antenna is ensured, the unfolding and folding efficiency of the space deployable mechanism is improved, and the lightweight is realized.

Description

Technical Field

[0001] This invention belongs to the field of space deployable antenna technology, and relates to a space deployable mechanism, specifically a bidirectional deployable modular parabolic cylindrical antenna space deployable mechanism, which can be applied to satellite communication, Earth observation, deep space exploration and other fields. Background Technology

[0002] With the rapid development of aerospace technology, the number of spacecraft in orbit is increasing, and the space electromagnetic environment is becoming increasingly complex. Traditional single-beam antennas are no longer able to operate normally in the current space environment. Parabolic cylindrical antennas, due to their unique reflector shape, can achieve multi-band signal sharing and automatic beam scanning, and have broad application prospects in the field of space deployable antenna technology. On the other hand, with the continuous development of space technology, the increasing size of the structure has become an inevitable trend in the development of spaceborne reflector antennas. However, due to the limitations of rocket launch space and capacity, traditional solid-surface antennas are difficult to design in a large scale. Therefore, large spaceborne antennas are developing towards high deployment-to-reception ratio, modularity, and lightweight design.

[0003] The deployment efficiency and weight of existing modular parabolic cylindrical antenna spatial deployable mechanisms still fall short of the requirements for large-scale spaceborne reflector antennas. For example, patent application CN 114865276 A, entitled "A Spatial Deployable Parabolic Antenna Back Frame Based on Thick Plate Origami Structure," discloses a spatial deployable parabolic antenna back frame based on a thick plate origami structure. This back frame includes multiple thick plate origami modules of different shapes and sizes, connected by hinges to form a single-degree-of-freedom thick plate deployable mechanism, capable of stretching and curved surface deformation. While this invention has a simple structure and a large deployment ratio, its drawback lies in the fact that the two quadrilateral thick plate units and four triangular thick plate units constituting the thick plate origami module all employ plate-like structures of a certain thickness, increasing the volume of the antenna after folding. This limits further improvement in the antenna back frame's deployment efficiency and also results in a bulky overall antenna back frame. Summary of the Invention

[0004] The purpose of this invention is to overcome the defects of the prior art and propose a bidirectional deployable modular parabolic cylindrical antenna spatial deployable mechanism. The aim is to ensure the surface accuracy of the parabolic cylindrical antenna while improving the deployment efficiency of the spatial deployable mechanism and reducing the weight of the deployable mechanism.

[0005] To achieve the above objectives, the technical solution adopted by the present invention includes multiple actively connected module units, wherein:

[0006] In the working state, the module unit has a double "day" - shaped structure with multiple moving joint components 1 as nodes, and the main rib components 2 and folding rod components 3 as transverse and longitudinal connecting members respectively. A motion locking device 4 is installed between each of the three shared moving joint components 1 in the double "day" - shaped structure and the main rib components 2 connected on both sides. A motion assisting device 5 is installed between two moving joint components 1 connected to both sides of the main rib component 2; the moving joint component 1 includes two elastic driving elements 11; the folding rod component 3 includes three folding rod hinges 31 located on its two sides and in the middle respectively, and a hinge scroll spring 311 is arranged inside the folding rod hinge 31.

[0007] The multiple module units are alternately connected through the moving joint components 1 with the main rib components 2 and the folding rod components 3 to achieve expansion in the transverse and longitudinal directions. By adjusting the included angle θ between the two main rib components 2 connected to the moving joint component 1 in the parabolic direction, the unfolded shape of the mechanism approximates an ideal parabolic cylinder surface.

[0008] The two elastic driving elements 11 in the moving joint component 1 drive the two main rib components 2 transversely connected to this moving joint component 1 to rotate through the elastic potential energy stored in them, so that the mechanism expands from the retracted state to the working state along the transverse direction, that is, the parabolic direction of the antenna. The hinge scroll springs 311 in the three folding rod hinges 31 in the folding rod component 3 drive the folding rod component 3 to unfold through the elastic potential energy stored in them, so that the mechanism expands from the retracted state to the working state along the longitudinal direction, that is, the generatrix direction of the parabolic cylinder surface of the antenna.

[0009] Preferably, the moving joint component 1 further includes a support frame 12 and two parallel transmission components 13; the transmission component 13 includes a transmission gear 131 fixed to the main rib component 2 and a transmission shaft 132 fixed to the folding rod component 2; the transmission gear 131 is fixed on the transmission shaft 132, and the transmission gears 131 in the two transmission components 13 mesh with each other and rotate towards each other under the drive of their respective elastic driving elements 11, driving the module unit to expand from the retracted state to the working state in the transverse direction.

[0010] Preferably, the elastic driving element 11 includes a scroll spring 111 and a spring box 112; the inner ring of the scroll spring 111 is fixed to the shaft end of the transmission shaft 132, and the outer ring is fixed to the spring box 112; the spring box 112 is fixed in the installation sink hole on the support frame 12.

[0011] Preferably, the main rib component 2 includes a first connecting rod 22 with first link joints 21 fixed at both ends, and a cable net adjusting device 23 fixed to the two first link joints 21; a cable for laying the antenna metal net is suspended on the cable net adjusting devices 23 in adjacent two rows of main rib components 2.

[0012] Preferably, the folding rod assembly 3 further includes a second connecting rod 32 disposed between the three folding rod hinges 31. In the folding rod hinge 31, one end of the folding rod hinges 31 located on both sides of the folding rod assembly 3 is fixed to the second connecting rod 32 through a second link joint 33, and the other end is fixed to the transmission shaft 132 in the transmission component 13. Both ends of the folding rod hinge 31 located in the middle of the folding rod assembly 3 are fixed to the second connecting rod 32 through the second link joint 33.

[0013] Preferably, the motion locking device 4 includes an active locking member 41 fixed to the first link joint 21 in the main rib assembly 2 and a passive locking member 42 fixed to the support frame 12 in the motion joint assembly 1. A push rod 411 and a wedge-shaped hook 412 are provided on the active locking member 41. The push rod 411 is used to prevent the mechanism from further unfolding after being unfolded in place, and the wedge-shaped hook 412 can slide into the hook groove 421 provided on the passive locking member 42 to prevent the mechanism from folding back in the reverse direction after being unfolded in place.

[0014] Preferably, the motion assisting device 5 includes a third connecting rod 52 with rotating joints 51 fixed at both ends. The rotating joint 51 includes a support shaft 511 and a third link joint 512 that can rotate around it. The support shaft 511 is fixed inside the support frame 12 in the motion joint assembly 1, and the third link joint 512 is fixed to the third connecting rod 52. The motion assisting device 5 and the main rib assembly 2 between the two motion joint assemblies 1 to which it is connected form a parallelogram mechanism.

[0015] Preferably, the first connecting rod 21, the second connecting rod 32, and the third connecting rod 52 are made of lightweight pipes.

[0016] Compared with the prior art, the present invention has the following advantages:

[0017] 1. In the present invention, the module unit presents a double "day" - shaped structure with multiple motion joint assemblies as nodes, and the main rib assembly and the folding rod assembly as the transverse connecting member and the longitudinal connecting member respectively. Except for the main rib assembly and the folding rod assembly connecting the motion joint assemblies, there are no solid parts in the remaining space, avoiding the defect in the prior art that each unit forming the thick - plate origami module has a certain thickness, resulting in a large volume after the antenna is folded. While ensuring the surface accuracy of the parabolic cylindrical antenna, on the one hand, it improves the deployment and retraction efficiency of the space deployable mechanism, and at the same time reduces the weight of the deployable mechanism, which is beneficial to achieving lightweight.

[0018] 2. The two motion joint components in this invention, together with the motion auxiliary device and the main rib component connected thereto, form a parallelogram mechanism. During the deployment of the mechanism, the support frame in the motion joint component will not deflect with the rotation of the transmission components inside, thereby improving the stability of the antenna mechanism's deployment and reception process. Attached Figure Description

[0019] Figure 1 This is a schematic diagram of the overall structure of the present invention;

[0020] Figure 2 This is a schematic diagram of the retracted state of the present invention;

[0021] Figure 3 This is a schematic diagram of the motion joint component structure of the present invention;

[0022] Figure 4 This is a schematic diagram of the main rib assembly structure of the present invention;

[0023] Figure 5 This is a schematic diagram of the cable net adjustment device of the present invention;

[0024] Figure 6 This is a schematic diagram of the rope adjustment assembly structure of the present invention;

[0025] Figure 7 This is a schematic diagram of the folding rod assembly structure of the present invention;

[0026] Figure 8 This is a schematic diagram of the folding rod hinge structure of the present invention;

[0027] Figure 9 This is a schematic diagram of the motion locking device of the present invention;

[0028] Figure 10 This is a schematic diagram of the motion assist device of the present invention;

[0029] Figure 11 This is a schematic diagram illustrating the connection method between the motion joint component and other components of the present invention. Detailed Implementation

[0030] The present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments:

[0031] This invention includes multiple actively connected module units.

[0032] Reference Figure 1 and Figure 2 The modular unit includes 9 motion joint components 1, 6 main rib components 2, 8 folding rod components 3, 6 motion locking devices 4, and 6 motion assisting devices 5; the modular unit is composed of, as follows Figure 2 The collapsed state shown unfolds as follows Figure 1A double "day" - shaped structure with the motion joint component 1 as the node, and the main rib component 2 and the folding rod component 3 as the transverse connecting member and the longitudinal connecting member respectively; A motion locking device 4 is installed between each of the three shared motion joint components 1 and the main rib components 2 connected on both sides, and a motion assisting device 5 is installed between the two motion joint components 1 connected on both sides of the main rib component 2, where:

[0033] For the motion joint component 1, its structural schematic diagram refers to Figure 3 , and it adopts a gearbox mechanism including an elastic driving element 11, a support frame 12, and a transmission component 13. The support frame 12 is a grooved metal part with round holes on both sides; The transmission component 13 includes a transmission gear 131, a transmission shaft 132, a bearing 133, and a bearing retaining ring 134. The transmission shaft 132 is installed in the round hole of the support frame 12 through the bearing 133, and the transmission gear 131 is located in the groove of the support frame 12 and is fixed to the transmission shaft 132 by key connection; The elastic driving element 11 includes a volute spring 111 and a spring box 112. The inner ring of the volute spring 111 is fixed to one end of the transmission shaft 132, and the outer ring is fixed to the support frame 12 through the spring box 112; When the mechanism is in the retracted state and compressed, the volute spring 111 stores a certain amount of elastic potential energy. When the mechanism is released, the volute spring 111 drives the transmission component 13 to rotate;

[0034] For the main rib component 2, its structural schematic diagram refers to Figure 4 , and it adopts a rib - shaped structure including a first link joint 21, a first connecting rod 22, and a cable net adjusting device 23; The first connecting rod 22 is a square - tubular thin - walled carbon fiber part to improve its bending strength and is fixed to the first link joint 21 by metal glue; During the unfolding process of the mechanism, the main rib component 2 remains relatively stationary with the connected motion joint component 1 through the first link joint 21;

[0035] For the cable net adjusting device 23, its structural schematic diagram refers to Figure 5 , which includes an actuator 231, an actuator sleeve 232, a reference plate 233, and a cable adjustment component 234. The actuator 231 is fixed in the first link joint 21 through the actuator sleeve 232, the reference plate 233 is fixed to the actuator 231 by bolts, and the position and angle of the reference plate 233 relative to the first connecting rod 22 below it are adjusted by the actuator 231; The cable adjustment component 234 is installed in the stud jack of the reference plate 233;

[0036] For the cable adjustment component 234, its structural schematic diagram refers to Figure 6The system includes a lower positioning assembly 2341 and an upper hanging rope assembly 2342. The lower positioning assembly 2341 includes a stud 23411 and two nuts 23412. The stud 23411 is inserted into a stud hole on a reference plate 233. The two nuts 23412 are screwed into the stud 23411 above and below the reference plate 233, respectively. The position of the stud 23411 relative to the reference plate 233 is adjusted by adjusting the two nuts 23412. The upper hanging rope assembly 2342 includes a spring 23421, a spring positioning element 23422, a clamping nut 23423, and a spring sleeve 23424. The spring 23421 is positioned by the spring positioning element. 23422 is fixed to the upper end of stud 23411. Spring positioning component 23422 is fixed to the upper end of stud 23411 by clamping nut 23423. Spring sleeve 23424 is made of flexible rubber material and is fixed to the outside of spring 23421 by spring positioning component 23422. Spring 23421 is used to suspend rope, and the metal reflector mesh of antenna is laid on the rope. Spring sleeve 23424 can prevent the metal mesh from contacting spring 23421 after being energized, which would cause leakage. By adjusting the lower positioning component 2341, the position of spring 23421 relative to the reference plate 233 is adjusted, thereby precisely adjusting the shape of the antenna mesh.

[0037] The structural schematic diagram of the folding rod assembly 3 is shown below. Figure 7 The mechanism employs a folding rod mechanism including a folding rod hinge 31, a second connecting rod 32, and a second connecting rod joint 33. A schematic diagram of the folding rod hinge 31 is shown below. Figure 8 The mechanism includes a hinge coil spring 311, a hinge gear 312, and a hinge bracket 313. The hinge coil spring 311 is installed inside the hinge gear 312, and its inner ring is fixed to the hinge bracket 313 by a pin, while its outer ring is fixed to the hinge gear 312 by bolts. The second connecting rod 32 is made of square tubular thin-walled carbon fiber parts to improve its bending strength. Both ends are fixed to the second connecting rod joint 33 by metal glue. The second connecting rod joint 33 is fixed to the end round tube of the hinge gear 312 by bolts. When the mechanism is in the retracted state and compressed, the hinge coil spring 311 stores a certain amount of elastic potential energy. When the mechanism is released, the hinge coil spring 311 drives the folding rod hinge 31 to unfold, thereby causing the folding rod assembly 3 to unfold, thus realizing the unfolding of the mechanism along the generatrix of the antenna parabolic cylinder.

[0038] The schematic diagram of the motion locking device 4 is shown below. Figure 9The device employs a bidirectional locking mechanism including an active locking element 41 and a passive locking element 42. The active locking element 41 includes a push rod 411, a wedge hook 412, and a base 413. The push rod 411 is fixed to a threaded hole on the side of the base 413 by a stud at its end. The wedge hook 412 is fixed to the bottom surface of the base 413 by bolts. The base 413 is fixed to the first connecting rod joint 21 by bolts. The passive locking element 42 includes a hook groove 421, a stop block 422, a hook groove shaft 423, and a torsion spring 424. The stop block 422 is fixed to the support frame 12 by bolts. The hook groove 421 and the stop block 422 are connected by the hook groove shaft 423 and can rotate around the hook groove shaft 423. The torsion spring 424 is arranged on the hook groove shaft 423.

[0039] When the mechanism is about to unfold into position, the top rod 411 contacts the stop block 422 to achieve the forward positioning function; after the wedge hook 412 slides into the hook groove 421, the hook groove 421 rebounds under the action of the torsion spring 424 to achieve the reverse locking function.

[0040] The schematic diagram of the motion assist device 5 is shown below. Figure 10 The mechanism employs a linkage mechanism including a rotating joint 51 and a third connecting rod 52. The rotating joint 51 includes a support shaft 511, a third connecting rod joint 512, a bearing 513, and an elastic retaining ring 514. The support shaft 511 is fixed to the support frame 12 by bolts, and the third connecting rod joint 512, bearing 513, and elastic retaining ring 514 are arranged on the support shaft 511. The third connecting rod 52 is made of a cylindrical thin-walled carbon fiber part to reduce its processing cost, and its two ends are fixed to the third connecting rod joint 512 by metal glue. During the deployment of the mechanism, the motion assist device 5, the two connected motion joint components 1, and the main rib component 2 between the motion joint components 1 form a parallelogram mechanism to ensure that the support frame 12 in the motion joint component 1 only undergoes translation and does not deflect with the rotation of the transmission component 13 inside it.

[0041] In the module unit, the connection method between the motion joint component 1 and other components is as follows: Figure 11 As shown, the transmission gear 131 is fixed to the first connecting rod joint 21 of the main rib assembly 2 by bolts, as shown in the figure. Figure 11 Part A; the drive shaft 132 and the hinge gear 312 of the folding rod hinge 31 are fixed by bolts, see reference. Figure 11 Part B; the support frame 12 and the stop block 422 of the motion locking device 4 are fixed by bolts, see reference. Figure 11 Part C; the support frame 12 and the support shaft 511 of the motion assist device 5 are fixed by bolts, see reference. Figure 11 Part D.

[0042] The multiple module units are alternately connected to the motion joint assembly 1, the main rib assembly 2, and the folding rod assembly 3 to achieve expansion in the lateral and longitudinal directions. By adjusting the angle θ between the two main rib assemblies 2 connected to the motion joint assembly 1 in the parabolic direction, the unfolded shape of the mechanism is made to approximate an ideal parabolic cylinder.

[0043] In the spatially deployable mechanism, the two elastic drive elements 11 in the motion joint assembly 1 drive the two main rib assemblies 2 that are laterally connected to the motion joint assembly 1 to rotate through their stored elastic potential energy, so that the mechanism is deployed from the folded state along the lateral direction, i.e., the parabolic direction of the antenna, to the working state; the hinge coil springs 311 in the three folding rod hinges 31 in the folding rod assembly 3 drive the folding rod assembly 3 to unfold through their stored elastic potential energy, so that the mechanism is deployed from the folded state along the longitudinal direction, i.e., the parabolic generatrix direction of the antenna, to the working state.

[0044] By connecting 16 modular units in a 4×4 arrangement, a parabolic cylindrical antenna mechanism with an outer perimeter of 8m×8m is formed. Specifically, the support frame 12 in the motion joint assembly 1 has an outer perimeter of 100mm×65mm×70mm; the first connecting rod 22 in the main rib assembly 2 has an outer perimeter of 50mm×42mm×770mm and a wall thickness of 1.5mm; and the second connecting rod 32 in the folding rod assembly 3 has an outer perimeter of 35mm×15mm×320mm and a wall thickness of 2.5mm. The dimensions of the remaining parts are designed based on these three parts. Simulation analysis shows that the outer perimeter of the mechanism after folding is 1606mm×2631mm, with an expansion-to-contraction ratio of approximately 13:1.

Claims

1. A bidirectional deployable modular parabolic cylindrical antenna spatial deployable mechanism comprising a plurality of movably connected modular units, characterized in that, The module unit in working state is in the shape of double "day" with multiple motion joint assemblies (1) as nodes, main rib assemblies (2) and folding rod assemblies (3) as transverse and longitudinal connecting members respectively, one motion locking device (4) is installed between the three commonly used motion joint assemblies (1) and the main rib assemblies (2) connected on both sides, and a motion auxiliary device (5) is installed between the two motion joint assemblies (1) connected on both sides of the main rib assemblies (2); the motion joint assembly (1) comprises two elastic driving elements (11); the folding rod assembly (3) comprises three folding rod hinges (31) arranged on both sides and in the middle of the folding rod assembly (3), and a hinge volute spring (311) is arranged in the folding rod hinge (31); the elastic driving element (11) comprises a volute spring (111) and a spring box (112); the motion locking device (4) comprises a driving locking member (41) and a driven locking member (42), a top rod (411) and a wedge-shaped hook (412) are arranged on the driving locking member (41); the motion auxiliary device (5) comprises a third connecting rod (52) with rotating joints (51) fixed at both ends; the rotating joint (51) comprises a support shaft (511) and a third connecting rod joint (512) which can rotate around the support shaft (511); the multiple module units are connected alternately by the motion joint assemblies (1), the main rib assemblies (2) and the folding rod assemblies (3), the expansion in the transverse and longitudinal directions is realized, and the expansion shape of the mechanism is close to the ideal parabolic cylindrical surface by adjusting the included angle θ of the two main rib assemblies (2) connected with the motion joint assembly (1) in the parabolic direction; the two elastic driving elements (11) in the motion joint assembly (1) drive the two main rib assemblies (2) connected with the motion joint assembly (1) in the transverse direction by the elastic potential energy stored therein, so that the mechanism is expanded from the folded state to the working state in the transverse direction, i.e. the parabolic direction of the antenna; the hinge volute springs (311) in the three folding rod hinges (31) in the folding rod assembly (3) drive the folding rod assembly (3) to expand by the elastic potential energy stored therein, so that the mechanism is expanded from the folded state to the working state in the longitudinal direction, i.e. the parabolic cylindrical generatrix direction of the antenna.

2. The deployable mechanism of claim 1, wherein, the motion joint assembly (1) further comprises a support frame (12) and two parallel transmission components (13); the transmission component (13) comprises a transmission gear (131) fixed with the main rib assembly (2) and a transmission shaft (132) fixed with the folding rod assembly (3); the transmission gear (131) is fixed on the transmission shaft (132), the transmission gears (131) in the two transmission components (13) are meshed with each other, and are rotated towards each other under the drive of the respective elastic driving elements (11), so that the module unit is expanded from the folded state to the working state in the transverse direction.

3. The deployable mechanism of claim 2, wherein, the inner ring of the volute spring (111) is fixed with the shaft end of the transmission shaft (132), and the outer ring is fixed with the spring box (112); the spring box (112) is fixed in the mounting counterbore on the support frame (12).

4. The deployable mechanism of claim 3, wherein, The main rib assembly (2) comprises a first connecting rod (22) with a first connecting rod joint (21) fixed at both ends, and a cable net adjusting device (23) fixed with the two first connecting rod joints (21); the cable net adjusting device (23) in the adjacent two rows of main rib assemblies (2) is hung with a rope for laying an antenna metal net.

5. The deployable mechanism of claim 4, wherein, The folding rod assembly (3) further comprises a second connecting rod (32) arranged between the three folding rod hinges (31); in the folding rod hinges (31), one end of the folding rod hinges (31) located on both sides of the folding rod assembly (3) is fixed with the second connecting rod (32) through a second connecting rod joint (33), and the other end is fixed with a transmission shaft (132) in the transmission part (13); both ends of the folding rod hinge (31) located in the middle of the folding rod assembly (3) are fixed with the second connecting rod (32) through the second connecting rod joint (33).

6. The deployable mechanism of claim 5, wherein, The movement locking device (4), the driving locking part (41) is fixed with the first connecting rod joint (21) in the main rib assembly (2), and the passive locking part (42) is fixed with the support frame (12) in the movement joint assembly (1); the top rod (411) is used for preventing the mechanism from continuing to expand after being expanded to the position, and the wedge-shaped hook (412) can slide into the hook groove (421) arranged on the passive locking part (42) to prevent the mechanism from being reversely folded after being expanded to the position.

7. The deployable mechanism of claim 5, wherein, The movement auxiliary device (5), the support shaft (511) is fixed in the support frame (12) in the movement joint assembly (1), and the third connecting rod joint (512) is fixed with the third connecting rod (52); the movement auxiliary device (5) and the two movement joint assemblies (1) connected and the main rib assembly (2) between the movement joint assemblies (1) constitute a parallelogram mechanism.

8. The deployable mechanism of any one of claims 2 to 7, wherein, The first connecting rod (21), the second connecting rod (32) and the third connecting rod (52) adopt light pipe materials.

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