Annular deployable antenna based on multistage parallel shear fork mechanism

Abstract

The invention belongs to the technical field of satellite-borne deployable antennas, and particularly relates to an annular deployable antenna based on a multistage parallel shear fork mechanism. According to the technical scheme, the annular deployable antenna based on the multistage parallel shear fork mechanism comprises a plurality of truss shear fork mechanism units, unit connecting components and a rope driving system, and every two adjacent truss shear fork mechanism units are connected together through two unit connecting components; the plurality of truss shear fork mechanism units are connected in parallel to form the linkage type annular deployable antenna, and the rope driving system is used for providing power for the annular deployable antenna from a folded state to an unfolded state. According to the annular deployable antenna based on the multi-stage parallel shear fork mechanism, a parallel mechanical transmission path is formed in the unfolding process of the multi-stage shear fork mechanism and used for dispersing loads, improving the rigidity and stability of the whole truss and avoiding the risk of single-point failure, and uniform transmission of driving force on the two sides is ensured through a parallel driving path; the structure is simple, stability is high, and overall structural rigidity is large.

Description

Technical Field

[0001] The present invention belongs to the technical field of satellite-borne deployable antennas, and in particular relates to a ring-shaped deployable antenna based on a multi-stage parallel scissor mechanism. Background Art

[0002] With the rapid development of aerospace technology in fields such as Earth observation, deep space exploration, and navigation and remote sensing, the performance of deployable antennas, core components of new spacecraft, directly impacts their payload capacity and on-orbit performance. Limited by the limited volume of launch vehicle fairings and payload constraints, current deployable antennas in space generally fold and stow on the ground and deploy autonomously in orbit. This places stringent demands on the antennas for high stowage efficiency, high deployment accuracy, and structural reliability.

[0003] Existing technologies primarily include four structural forms for deployable space antennas: frame, rib, ring truss, and tensegrity. The ring truss exhibits a unique nonlinear mass-aperture growth characteristic, meaning that the mass of the antenna does not increase proportionally with the aperture. This significantly enhances the design of ultra-large aperture antennas and is considered a key technology for deep space exploration.

[0004] There are two common technical solutions for the current design of annular deployable antennas: one uses a parallelogram structure represented by the AstroMesh series of antennas as the basic unit, and uses the contraction of the diagonal web to achieve the folding and unfolding of the basic unit truss. The typical structure has a caliber of up to 12.5m, and the ratio of the caliber of expansion to contraction, that is, the storage rate, is about 10:1. The structure is relatively compact after folding, which can better meet the strict volume restrictions of spacecraft. The parallelogram mechanism ensures that the reflective surface of the antenna is evenly stressed during deployment through geometric symmetry, reducing the risk of deformation, thereby maintaining high surface accuracy of electromagnetic signal transmission. However, this configuration has high requirements for node synchronization. If individual nodes are out of synchronization due to friction or jamming during deployment, it may cause structural distortion or even deployment failure. The second is a large-diameter deployable antenna designed by the European Space Agency (ESA). This antenna uses a scissors-type mechanism that slides with the support truss to replace the upper and lower beams of the parallelogram unit, and replaces the contraction of the diagonal web by the expansion and closure of the scissors-type mechanism. It adopts a repeated scissor-type modular ring configuration and can be applied to antennas of different sizes. The storage rate of this antenna can reach 10.2:1, and it also has a relatively excellent expansion-contraction diameter ratio. However, due to the presence of the moving pair in the mechanism, it is affected by the harsh environment of space vacuum and transient high and low temperatures. Cold welding is prone to occur in the mechanism on orbit, which in turn causes deployment failures. For example, the failure of the ESA satellite antenna in 2020 and the abnormality of the NASA lunar probe robotic arm in 2021 were caused by cold welding of the aluminum hinge friction pair in a high vacuum environment, resulting in deployment jamming.

[0005] The existing typical annular deployable antenna has shown outstanding advantages in terms of storage rate, but it also has certain shortcomings. Therefore, it is urgent to propose a new configuration of annular truss deployable antenna to meet the urgent needs of future space missions for large aperture, high storage rate and lightweight satellite antennas. Summary of the Invention

[0006] The present invention provides a ring-shaped deployable antenna based on a multi-stage parallel scissor-type mechanism. The multi-stage scissor-type mechanism forms a parallel mechanical transmission path during the deployment process, which is used to disperse the load and improve the stiffness and stability of the overall truss, avoiding the risk of single-point failure. The parallel drive path ensures uniform transmission of driving force on both sides; the antenna has a simple structure, high stability, and high overall structural stiffness.

[0007] The technical solutions of the present invention are as follows:

[0008] A ring-shaped deployable antenna based on a multi-stage parallel scissor mechanism includes multiple truss scissor mechanism units, unit connecting components and a rope drive system. Two adjacent truss scissor mechanism units are connected together by two unit connecting components. Multiple truss scissor mechanism units are connected in parallel to form a linked ring-shaped deployable antenna. The rope drive system is used to provide power for the ring-shaped deployable antenna to move from a folded state to an expanded state.

[0009] Furthermore, the annular expandable antenna based on the multi-stage parallel scissors mechanism, the truss scissors mechanism unit includes a main scissors structure, four pin shafts and two secondary scissors structures, the main scissors structure includes two scissors rods and a center hinge, the middle parts of the two scissors rods are rotatably connected together through the center hinge; the secondary scissors structure includes two elbow rods, a pin shaft 2, a synchronization structure and two pin shafts 3, one end of the scissors rod is rotatably connected to the straight end of an elbow rod through a pin shaft 1, and the middle parts of the elbows of the two elbow rods are rotatably connected together through the pin shaft 2; the synchronization mechanism includes two synchronization rods, a pulley and a pin shaft 4, one end of the synchronization rod is rotatably connected to the elbow end of an elbow rod through the pin shaft 3, the other end of the synchronization rod is rotatably connected to the pin shaft 4, and the pulley is rotatably connected to the pin shaft 4; the truss scissors mechanism unit is distributed in a mirror-symmetrical manner about the horizontal projection of the center.

[0010] Furthermore, the annular expandable antenna based on the multi-stage parallel scissors-type mechanism, the unit connecting component includes a connector, a routing wheel and a locking structure, the two sides of the connector are connecting ends respectively, the connecting end is provided with an outward opening groove, the angle between the two connecting ends is the inner angle of a regular polygon, each connecting end is rotatably connected to a pin shaft of a truss scissors-type mechanism unit; two bases are symmetrically arranged on the lower end surface of the connector, and each base is rotatably connected to a routing wheel; the locking structure is arranged in the opening groove for locking the position between the connector and the elbow rod when the annular expandable antenna is in the expanded state.

[0011] Furthermore, the annular expandable antenna based on the multi-stage parallel scissors-type mechanism, the locking structure includes a locking piece, a pin shaft five and a torsion spring, the lower part of the locking piece is provided with two symmetrically distributed sleeves, the upper end of the locking piece is provided with a clamping rod, the pin shaft five is installed on the two side walls of the opening groove, the sleeve and the torsion spring are sleeved on the pin shaft five, the torsion spring is located between the two sleeves, one end of the torsion spring is close to the bottom wall of the opening groove, and the other end is close to the locking piece; a clamping slot is provided at the straight end of the elbow rod, and when the annular expandable antenna is in the expanded state, the clamping rod enters the clamping slot under the action of the torsion spring to complete the locking.

[0012] Furthermore, in the annular expandable antenna based on the multi-stage parallel scissors mechanism, a limit pin is provided in the middle of the synchronization rod. When the annular expandable antenna is in the expanded state, the limit pin clamps and supports the elbow rod to limit it.

[0013] Furthermore, in the annular expandable antenna based on the multi-stage parallel scissors-type mechanism, a connecting sleeve is sleeved on the pin shaft, and the connecting sleeve is located between the scissors-type rod and the connecting piece.

[0014] Furthermore, in the annular expandable antenna based on a multi-stage parallel scissors-fork mechanism, the connecting member is provided with a wiring groove; the rope drive system includes two driving ropes, and the two driving ropes are arranged in a mirror-symmetrical manner about the horizontal projection of the center; the starting end of the single driving rope is fixedly mounted on a wiring wheel of the initial unit connecting member, and then the driving rope is wound around the pulley of the initial truss scissors-fork mechanism unit, and then the driving rope is wound around the wiring wheel of the adjacent unit connecting member and the pulley of the adjacent truss scissors-fork mechanism unit, and then it is wound around the wiring wheel of other unit connecting members and the pulley of the truss scissors-fork mechanism unit in turn, and finally it is wound around another wiring wheel of the initial unit connecting member, and is wound out from the wiring groove of the connecting member to be connected to the external drive motor.

[0015] Furthermore, in the annular expandable antenna based on the multi-stage parallel scissors-fork mechanism, the pin shafts four of the two synchronous structures of the truss scissors-fork mechanism unit are connected by a stabilizing retaining rope, and the stabilizing retaining rope has elastic force so that the two synchronous structures always remain on the same axis.

[0016] Furthermore, in the annular expandable antenna based on a multi-stage parallel scissors-fork mechanism, when the annular expandable antenna is in a folded state, the two scissors rods of the main scissors-fork structure of the truss scissors-fork mechanism unit are merged, the two elbow rods of the secondary scissors-fork structure are merged, and the synchronization structure is located in the middle of the merged scissors rods.

[0017] Furthermore, the annular expandable antenna based on the multi-stage parallel scissors-fork mechanism is in a folded state, and the driving cable is driven by an external driving motor to pull the pulley to move, thereby driving the two elbow rods of the secondary scissors-fork structure to open while the two scissors-fork rods of the main scissors-fork structure to open, so that the annular expandable antenna is in an expanded state to form an annular structure; at this time, the limit pin supports the elbow rod to limit it, and the clamping rod enters the clamping slot under the action of the torsion spring to complete the locking.

[0018] The beneficial effects of the present invention are:

[0019] 1. The present invention adopts multiple truss scissor-type mechanism units connected together by unit connecting components. Multiple truss scissor-type mechanism units are connected in parallel to form a linked annular deployable antenna with high stability and large overall structural rigidity.

[0020] 2. The present invention adopts a modular design concept, which can meet the adaptability requirements by adjusting the unit structure parameters, making it easy to process and manufacture; by changing the rod length parameters of the truss scissor mechanism unit and the inner angle of the unit connection component, annular deployable antennas of different calibers can be formed.

[0021] 3. The annular deployable antenna of the present invention has only one degree of freedom and its main frame is composed of a scissor-type device. The overall structure is simple, the deployment process is easy to control, and it is suitable for space environment.

[0022] 4. The present invention achieves a higher level of deployment action through the main scissors structure and the secondary scissors structure; the multi-stage scissors mechanism forms a parallel mechanical transmission path during the deployment process, which is used to disperse the load and improve the stiffness and stability of the overall truss, avoiding the risk of single point failure. The parallel drive path ensures uniform transmission of driving force on both sides. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 Schematic diagram of the deployed state of the annular deployable antenna based on the multi-stage parallel scissor mechanism;

[0024] Figure 2 Schematic diagram of the folded state of the annular deployable antenna based on the multi-stage parallel scissor mechanism;

[0025] Figure 3 This is the main view of the truss scissor mechanism unit and the unit connection components;

[0026] Figure 4It is a top view of the truss scissor mechanism unit and the unit connection components;

[0027] Figure 5 This is a schematic diagram of the two scissor rods merging state;

[0028] Figure 6 It is a schematic diagram of the synchronization structure;

[0029] Figure 7 is a schematic diagram of the unit connection components;

[0030] Figure 8 for Figure 7 Middle AA cross-section;

[0031] Figure 9 is a schematic diagram of a locking member;

[0032] Figure 10 Schematic diagram of the installation relationship between the truss scissor mechanism unit, unit connecting components and rope drive system;

[0033] Figure 11 This is a schematic diagram of the state where the driving cable is installed on the initial unit connecting component;

[0034] Figure 12 Schematic diagram of the semi-deployed state of the annular deployable antenna based on the multi-stage parallel scissors mechanism. DETAILED DESCRIPTION

[0035] like Figure 1-12 As shown, a ring-shaped deployable antenna based on a multi-stage parallel scissors-type mechanism includes twelve truss scissors-type mechanism units, a unit connecting member 4 and a rope drive system. Two adjacent truss scissors-type mechanism units are connected together by two unit connecting members 4. The twelve truss scissors-type mechanism units are connected in parallel to form a linked ring-shaped deployable antenna. The rope drive system is used to provide power for the ring-shaped deployable antenna to move from a folded state to an expanded state.

[0036] The truss scissors mechanism unit includes a main scissors structure, four pins and two secondary scissors structures. The main scissors structure includes two scissors rods 1 and a center hinge 7. The middle parts of the two scissors rods 1 are rotatably connected together through the center hinge 7; the secondary scissors structure includes two elbow rods 2, a pin 2, a synchronization structure and two pins 3. One end of the scissors rod 1 is rotatably connected to the straight end of an elbow rod 2 through a pin 1, and the middle parts of the elbows of the two elbow rods 2 are rotatably connected together through the pin 2; the synchronization mechanism includes two synchronization rods 10, a pulley 3 and a pin 4 9. One end of the synchronization rod 10 is rotatably connected to the elbow end of an elbow rod 2 through the pin 3, and the other end of the synchronization rod 10 is rotatably connected to the pin 4 9. The pulley 3 is rotatably connected to the pin 4 9; the truss scissors mechanism unit is distributed in a mirror-symmetrical manner about the horizontal projection of the center.

[0037] The unit connecting member 4 includes a connecting member 12, a wiring wheel 16 and a locking structure. The two sides of the connecting member 12 are connecting ends respectively. The connecting ends are provided with outward opening grooves. The angle between the two connecting ends is the internal angle of a regular dodecagon. Each connecting end is rotatably connected to a pin shaft of a truss scissors mechanism unit; two bases are symmetrically arranged on the lower end surface of the connecting member 12, and each base is rotatably connected to a wiring wheel 16; the locking structure is arranged in the opening groove and is used to lock the position between the connecting member 12 and the elbow rod 2 when the annular expandable antenna is in the expanded state.

[0038] The locking structure includes a locking piece 13, a pin five and a torsion spring 14. The lower part of the locking piece 13 is provided with two symmetrically distributed sleeves 17, and the upper end of the locking piece 13 is provided with a clamping rod 18. The pin five is installed on the two side walls of the open groove. The sleeve 17 and the torsion spring 14 are sleeved on the pin five. The torsion spring 14 is located between the two sleeves 17. One end of the torsion spring 14 is close to the bottom wall of the open groove and the other end is close to the locking piece 13; a clamping slot is provided at the end of the straight section of the elbow rod 2. When the annular expandable antenna is in the expanded state, the clamping rod 18 enters the clamping slot under the action of the torsion spring 14 to complete the locking.

[0039] A limiting pin 11 is provided in the middle of the synchronization rod 10. When the annular expandable antenna is in the expanded state, the limiting pin 11 supports the elbow rod 2 to limit the position.

[0040] The connecting sleeve 8 is sleeved on the pin shaft, and the connecting sleeve 8 is located between the scissor rod 1 and the connecting piece 12.

[0041] The connecting member 12 is provided with a wiring groove 15; the rope drive system includes two driving ropes 5, and the two driving ropes 5 are arranged in a horizontal projection mirror symmetry about the center; the starting end of the single driving rope 5 is fixedly mounted on a wiring wheel 16 of the initial unit connecting member, and then the driving rope 5 is wound around the pulley 3 of the initial truss scissors mechanism unit, and then the driving rope 5 is wound around the wiring wheel 16 of the adjacent unit connecting member and the pulley 3 of the adjacent truss scissors mechanism unit, and then it is wound around the wiring wheel 16 of the other eleven unit connecting members and the pulley 3 of the truss scissors mechanism unit in turn, and finally it is wound around another wiring wheel 16 of the initial unit connecting member, and is wound out from the wiring groove 15 of the connecting member 12 to be connected to the external drive motor.

[0042] The pin shafts 9 of the two synchronous structures of the truss scissor-type mechanism unit are connected by a stable retaining cable 6. The stable retaining cable 6 has elastic force so that the two synchronous structures always remain on the same axis.

[0043] When the annular deployable antenna is in the retracted state, the two scissor rods 1 of the primary scissor structure of the truss scissor mechanism unit merge, and the two elbow rods 2 of the secondary scissor structure merge, with the synchronization structure located in the middle of the merged scissor rods 1. Driven by an external drive motor, the drive cable 5 pulls the pulley 3 to move, causing the two elbow rods 2 of the secondary scissor structure to open, while the two scissor rods 1 of the primary scissor structure open, placing the annular deployable antenna in the deployed state and forming a ring structure. At this time, the limit pin 11 supports the elbow rod 2 to limit its position, and the locking rod 18, under the action of the torsion spring 14, enters the slot at the straight end of the elbow rod 2 to complete the locking.

[0044] When the annular deployable antenna is in the folded state, it is highly folded and adapted to the size of the rocket fairing of the satellite body, meeting the volume limit of the launch vehicle; after the rocket reaches the designated working orbit, the drive motor controls the drive cable 5 to realize the folding action, driving the annular deployable antenna to gradually unfold from the folded state to an annular structure; after the unfolding is completed, the limit pin 11 clamps the pulley 3 to limit it, and the clamping rod 18 enters the clamping groove of the straight end of the elbow rod 2 under the action of the torsion spring 14 to complete the locking; at this time, the annular deployable antenna forms a stable annular support truss, and its central area forms the antenna reflection surface for receiving or transmitting electromagnetic wave signals.

Claims

1. A ring-shaped deployable antenna based on a multi-stage parallel scissor mechanism, characterized in that: It includes multiple truss scissor-type mechanism units, unit connecting components and a rope drive system. Two adjacent truss scissor-type mechanism units are connected together by two unit connecting components. Multiple truss scissor-type mechanism units are connected in parallel to form a linked annular deployable antenna. The rope drive system is used to provide power for the annular deployable antenna to move from a folded state to an deployed state.

2. The annular deployable antenna based on a multi-stage parallel scissor mechanism according to claim 1, characterized in that: The truss scissors mechanism unit includes a main scissors structure, four pin shafts and two secondary scissors structures. The main scissors structure includes two scissors rods and a center hinge. The middle parts of the two scissors rods are rotatably connected together through the center hinge; the secondary scissors structure includes two elbow rods, a pin shaft 2, a synchronization structure and two pin shafts 3. One end of the scissors rod is rotatably connected to the straight end of an elbow rod through a pin shaft 1, and the middle parts of the elbows of the two elbow rods are rotatably connected together through the pin shaft 2; the synchronization mechanism includes two synchronization rods, a pulley and a pin shaft 4. One end of the synchronization rod is rotatably connected to the elbow end of an elbow rod through the pin shaft 3, and the other end of the synchronization rod is rotatably connected to the pin shaft 4, and the pulley is rotatably connected to the pin shaft 4; the truss scissors mechanism unit is distributed in a mirror-symmetrical manner about the horizontal projection of the center.

3. The annular deployable antenna based on a multi-stage parallel scissor mechanism according to claim 2, characterized in that: The unit connecting component includes a connecting member, a wiring wheel and a locking structure. The two sides of the connecting member are connecting ends respectively. The connecting ends are provided with outward opening grooves. The angle between the two connecting ends is the inner angle of a regular polygon. Each connecting end is rotatably connected to a pin shaft of a truss scissors mechanism unit; two bases are symmetrically arranged on the lower end surface of the connecting member, and each base is rotatably connected to a wiring wheel; the locking structure is arranged in the opening groove and is used to lock the position between the connecting member and the elbow rod when the annular expandable antenna is in the expanded state.

4. The annular deployable antenna based on a multi-stage parallel scissor mechanism according to claim 3, characterized in that: The locking structure includes a locking piece, a pin shaft five and a torsion spring. The lower part of the locking piece is provided with two symmetrically distributed sleeves, the upper end of the locking piece is provided with a clamping rod, the pin shaft five is installed on the two side walls of the open groove, the sleeve and the torsion spring are sleeved on the pin shaft five, and the torsion spring is located between the two sleeves. One end of the torsion spring is close to the bottom wall of the open groove, and the other end is close to the locking piece; a clamping slot is provided at the straight end of the elbow rod. When the annular expandable antenna is in the expanded state, the clamping rod enters the clamping slot under the action of the torsion spring to complete the locking.

5. The annular deployable antenna based on a multi-stage parallel scissor mechanism according to claim 2, characterized in that: A limiting pin is provided in the middle of the synchronization rod. When the annular expandable antenna is in the expanded state, the limiting pin supports the elbow rod to limit the position.

6. The annular deployable antenna based on a multi-stage parallel scissor mechanism according to claim 2, characterized in that: A connecting sleeve is sleeved on the pin shaft, and the connecting sleeve is located between the scissor rod and the connecting piece.

7. The annular deployable antenna based on a multi-stage parallel scissor mechanism according to claim 3, characterized in that: The connecting member is provided with a wiring groove; the rope drive system includes two driving ropes, and the two driving ropes are arranged in a mirror-symmetrical manner about the horizontal projection of the center; the starting end of the single driving rope is fixedly installed on a wiring wheel of the initial unit connecting member, and then the driving rope is wound around the pulley of the initial truss scissors mechanism unit, and then the driving rope is wound around the wiring wheel of the adjacent unit connecting member and the pulley of the adjacent truss scissors mechanism unit, and then it is wound around the wiring wheel of other unit connecting members and the pulley of the truss scissors mechanism unit in turn, and finally it is wound around another wiring wheel of the initial unit connecting member, and is wound out from the wiring groove of the connecting member to be connected to the external drive motor.

8. The annular deployable antenna based on a multi-stage parallel scissor mechanism according to claim 7, characterized in that: The pin shafts 4 of the two synchronous structures of the truss scissor-type mechanism unit are connected by a stable retaining cable. The stable retaining cable has elastic force so that the two synchronous structures always remain on the same axis.

9. The annular deployable antenna based on a multi-stage parallel scissor mechanism according to claim 7, characterized in that: When the annular deployable antenna is in the folded state, the two scissor rods of the main scissor structure of the truss scissor mechanism unit are merged, the two elbow rods of the secondary scissor structure are merged, and the synchronization structure is located in the middle of the merged scissor rods.

10. The annular deployable antenna based on a multi-stage parallel scissor mechanism according to claim 9, characterized in that: The annular deployable antenna is in a folded state, and the driving cable is driven by an external driving motor to pull the pulley to move, driving the two elbow rods of the secondary scissor structure to open while the two scissor rods of the main scissor structure open, so that the annular deployable antenna is in an deployed state to form an annular structure; at this time, the limit pin supports the elbow rod to limit it, and the clamping rod enters the clamping slot under the action of the torsion spring to complete the locking.

Images