A system and method for reducing oscillation of a barrier line for a rocket tether capture system

Abstract

The application provides a blocking cable anti-swing system and anti-swing method for a rocket tethered capture system, which uses adjacent warp and weft of the tethered capture system as the basis of interaction, and installs anti-swing units at the intersection of the warp and weft. Each group of anti-swing units of the application is combined by two backstoppers, each of which is configured to slide in one direction of the corresponding blocking cable and stop in the opposite direction. The anti-swing system of the application always maintains the backstop state after being assembled with the tethered capture system. During the process of the tethered capture system capturing the rocket, i.e. the process of each blocking cable moving towards the rocket stage (the center position of the rocket tethered capture system), each cam smoothly slides with the corresponding blocking cable. When the blocking cable is disturbed to swing in the opposite direction, each cam limits the reverse sliding of the corresponding blocking cable, thereby limiting the reverse swing of each blocking cable.

Description

Technical Field

[0001] This invention relates to the field of space launch vehicle recovery technology, and in particular to an arresting cable anti-sway system and method for rocket cable capture systems. Background Technology

[0002] With the continuous development of reusable launch vehicle technology, vertical rocket recovery technology has become an important way to reduce the cost of space launches. Currently, the mainstream rocket recovery methods include powered vertical landing and net / tether capture and recovery. Among them, the tether (also known as net) rocket recovery system has received widespread attention from the industry due to its advantages such as relatively low requirements for rocket landing accuracy and controllable impact loads during the recovery process.

[0003] Related technologies, such as the cable-guided rocket recovery systems disclosed in patent applications CN 117963181 A, CN 117963180 A, CN 117963179 A, ​​CN 117963178 A, and CN 121430400 A, mainly consist of four recovery platforms. A slide rail connects two adjacent recovery platforms, and the four recovery platforms and four slide rails are arranged in a rectangular pattern. A trolley is slidably mounted on each slide rail, and an arresting cable connects the trolleys on two opposite slide rails. A traction device is installed between two adjacent recovery platforms. During rocket recovery, the traction device pulls the trolleys between adjacent recovery platforms along the slide rails, thereby causing the arresting cable to converge towards the center of the recovery platform to intercept and capture the descending rocket.

[0004] However, the aforementioned cable-guided rocket recovery system still faces the following technical challenges in practical applications: Because the pulley span is relatively large (usually not less than 44 meters), the arresting cable, except for the sections connected to the pulleys at both ends, is in a free, unconstrained state in the middle section. Under external excitation conditions, such as ship motion caused by sea waves and equipment vibration, the arresting cable is prone to large-amplitude low-frequency swaying. More importantly, in the final stage of the rocket's descent to the recovery platform, the traction device drives the pulley, which in turn moves the arresting cable closer to the rocket body. When the rocket lands at a height where the hook on the rocket body is close to the arresting cable, the rocket's tail is already very close to the deck surface of the recovery vessel. Since the existing recovery vessels do not have exhaust gas flow guidance structures on their hull surfaces, the high-speed exhaust gas ejected from the rocket engine impacts the deck and is reversed, creating a strong turbulent airflow field. The reverse-flowing gas generates intense aerodynamic excitation on the arresting cable. In addition, the arresting cable is a flexible structure supported at both ends and free in the middle, which significantly amplifies the swaying amplitude. This causes the arresting cable to be in a state of violent and irregular swinging at the moment of attachment to the rocket hook, making it difficult for the rocket hook to accurately engage with the arresting cable. This poses a risk of failure to engage the cable and seriously affects the reliability and safety of rocket recovery.

[0005] Therefore, there is an urgent need to provide an arresting cable anti-sway system and anti-sway method for rocket cable-mounted capture systems. Summary of the Invention

[0006] To solve the above-mentioned technical problems, this invention proposes an anti-sway system and method for arresting cables in rocket cable-locked capture systems. The system utilizes adjacent meridians and parallels of the cable-locked capture system as the basis for their interaction, and an anti-sway device is installed at the intersection of meridians and parallels.

[0007] This invention provides an arresting cable anti-sway system for a rocket tethered capture system, comprising at least: a first anti-sway unit disposed at the intersection of a first arresting cable and a second arresting cable; a second anti-sway unit disposed at the intersection of a second arresting cable and a third arresting cable; a third anti-sway unit disposed at the intersection of a third arresting cable and a fourth arresting cable; and a fourth anti-sway unit disposed at the intersection of a fourth arresting cable and a first arresting cable. The first anti-sway unit comprises at least a first anti-reverse device, a second anti-reverse device, and a linkage mechanism. The first anti-reverse device is slidably mounted on the first arresting cable, and the second anti-reverse device is slidably disposed on the second arresting cable. The first and second anti-reverse devices are spatially staggered. The linkage mechanism is connected to the first... The first and second backstops are linked to each other; wherein the first backstop is configured to move only along the first arresting cable toward the center position of the rocket tether capture system; the second backstop is configured to move only along the second arresting cable toward the center position of the rocket tether capture system; the movement of the first arresting cable toward the center position of the rocket tether capture system causes the second backstop to move along the axis of the second arresting cable toward the center position of the rocket tether capture system via the first backstop; the movement of the second arresting cable toward the center position of the rocket tether capture system causes the first backstop to move along the axis of the first arresting cable toward the center position of the rocket tether capture system via the second backstop.

[0008] In one embodiment, the first backstop and the second backstop have the same structure; the first backstop includes at least: a housing, a cover plate, a sliding sleeve, a first cam, and a second cam; the housing is a U-shaped structure with an opening on one side, and its bottom is provided with a longitudinal mounting groove parallel to the side of the U-shaped structure; the cover plate is fixedly installed at the opening end of the housing and surrounds the housing to form a receiving cavity; the sliding sleeve is a cylindrical structure, fixedly disposed in the longitudinal mounting groove, and has symmetrical grooves in its radial direction; the first cam and the second cam are rotatably pressed against the radial sides of the sliding sleeve by a torsion spring, and at least partially embedded in the grooves of the sliding sleeve, thereby forming a rope clearance for the arresting cable to pass through; the first cam and the second cam are configured to: when the... When the first backstop slides along the first direction of the first arresting cable, the first cam and the second cam, driven by the frictional force of the first arresting cable, overcome the elastic force of the torsion spring and rotate away from the first arresting cable, thereby increasing the cable clearance. When the first backstop moves along the second direction of the first arresting cable, the first cam and the second cam, under the action of the torsion spring, rotate towards the first arresting cable, contact and rub against the first arresting cable, thereby decreasing the cable clearance and clamping the arresting cable under the frictional force of the first arresting cable. The first direction is the direction toward the center of the rocket cable capture system, and the second direction is opposite to the direction of the first direction.

[0009] In one embodiment, the first cam and / or the second cam includes at least a cam body and a hinge shaft; the end of the cam body away from the arresting cable is provided with a sandwich-type upper and lower double-layer clamping plate, the torsion spring is accommodated between the upper and lower double-layer clamping plates, the hinge shaft passes through the upper clamping plate, the torsion spring and the lower clamping plate and is rotatably connected to the inner wall of the side of the housing; the torsion spring is clamped between the inner wall of the side of the housing and the cam body, and the cam body abuts against the arresting cable under the elastic compression force of the torsion spring.

[0010] In one embodiment, the present invention further includes a pulling unit and a positioning unit; the pulling unit acts on the cam body at a position away from the hinge axis and the center of the rocket cable capture system; after the cam body is rotated around the hinge axis to the release position by the pulling unit, the positioning unit locks the cam body in the release position.

[0011] In one embodiment, the present invention further includes a release mechanism, which includes at least a cable system, a traction pin, and a reset plunger, as well as a mounting hole and a reset hole disposed on the cam body. The mounting hole and the reset hole are disposed on the side of the cam body away from the hinge axis, and the reset hole is closer to the center of the arresting cable and rocket cable capture system than the mounting hole. The cover plate has an arc-shaped hole with the same rotation trajectory as the traction pin, and the traction pin passes through the mounting hole and the arc-shaped hole and connects to the cable system. The reset hole is disposed on a circumference with a set radius centered on the hinge axis. One end of the reset plunger is mounted on the housing, and the other end elastically abuts against the cam body under its own elastic force, and the axial projection of the reset plunger on the cam body falls on the circumference. By pulling the traction pin through the cable system, the cam body rotates away from the arresting cable with the hinge axis as the center. When the axis of the reset plunger is collinear with the center line of the reset hole, the reset plunger can be inserted into the reset hole to maintain the released state.

[0012] In one embodiment, the portion of the traction pin extending beyond the cover plate has a mating hole, and the outer surface of the cover plate has an eye bolt. The central axis of the eye bolt's eye hole is collinear with the central axis of the traction pin's mating hole. The cable passes through the eye bolt's eye hole and connects to the traction pin's mating hole.

[0013] In one embodiment, the portions of the first cam and the second cam embedded in the groove are provided with teeth, and each of the arresting cables has a plurality of annular protrusions at equal intervals along its own axial direction on its outer peripheral surface. The teeth mesh with the protrusions to allow the first backstop to slide along the first direction of the first arresting cable and to prevent the first backstop from sliding along the second direction of the first arresting cable.

[0014] In one embodiment, the linkage mechanism is a spherical bearing assembly; the first backstop and the second backstop are assembled together via the spherical bearing assembly, which allows rotation and oscillation between the first backstop and the second backstop.

[0015] In any of the above embodiments, the first anti-sway unit, the second anti-sway unit, the third anti-sway unit, and the fourth anti-sway unit have the same structure.

[0016] Another aspect of the present invention provides a method for preventing swaying of the arresting cable in a rocket cable-based capture system. Using the arresting cable sway prevention system described in any of the above embodiments to prevent swaying during the rocket cable-based capture process, the method includes at least the following steps: Step 1: Install the rocket arresting cable system in place, making the first arresting cable parallel to the third arresting cable, the second arresting cable parallel to the fourth arresting cable, and the first arresting cable intersecting with the second and fourth arresting cables respectively, and the third arresting cable intersecting with the second and fourth arresting cables respectively. Step 2: Install a first backstop on the first barrier cable and a second backstop on the second barrier cable. Slide the first and second backstops to the position where the first and second barrier cables intersect, and connect the first and second backstops through a linkage mechanism to form a first anti-sway unit. Step 3: Referring to the method in Step 2, set up a second anti-sway unit at the intersection of the second and third barrier cables, a third anti-sway unit at the intersection of the third and fourth barrier cables, and a fourth anti-sway unit at the intersection of the fourth and first barrier cables. Step 4: Configure the first and second backstops in each anti-sway unit to move only along the corresponding arresting cable toward the center position of the rocket cable capture system. Step 5: When the rocket stage lands in the area enclosed by the first arresting cable, the second arresting cable, the third arresting cable, and the fourth arresting cable are opened, and the first arresting cable, the second arresting cable, the third arresting cable, and the fourth arresting cable are driven to move synchronously towards the center of the rocket cable capture system. Each arresting cable drives the anti-sway unit on the adjacent arresting cable to move synchronously. Step Six: When the rocket descends to a height where the rocket hook is close to the arresting cable, the tail of the rocket approaches the surface of the recovery ship. The turbulence caused by the backflow of the engine exhaust acts on each arresting cable. Each arresting cable is prevented from swaying away from the center of the rocket tether capture system by the backstop on the adjacent arresting cable, so that each arresting cable always moves towards the center of the rocket tether capture system until the rocket hook is successfully engaged.

[0017] The present invention provides an arresting cable anti-sway system and method for rocket cable-guided capture systems, which has at least one of the following beneficial effects: I. This invention, by setting anti-sway units at the intersection of two adjacent arresting cables, constrains the adjacent arresting cables to each other. The meridian can restrict the latitude line from moving along the meridian towards the center of the rocket cable capture system, and the latitude line restricts the meridian line from moving along the latitude line towards the center of the rocket cable capture system. This eliminates the risk of the four arresting cables swaying under the action of gas turbulence, completely avoids rocket cable failure caused by arresting cable swaying, and improves the reliability of rocket recovery.

[0018] Second, the anti-sway system of the present invention has a release mechanism for the backstop. After release, the backstop can slide bidirectionally with the blocking cable so that the backstop can return to the initial position with the corresponding blocking cable.

[0019] Upon reading the detailed embodiments and examining the accompanying drawings, those skilled in the art will recognize additional features and advantages. Attached Figure Description

[0020] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0021] Figure 1 This is a schematic diagram of the overall structure of the arresting cable anti-sway system according to an embodiment of the present invention.

[0022] Figure 2 This is a three-dimensional structural diagram of the first anti-sway unit (which is also the second, third, and fourth anti-sway unit) according to an embodiment of the present invention.

[0023] Figure 3 This is a three-dimensional structural diagram of the first and second backstops according to an embodiment of the present invention.

[0024] Figure 4 This is an exploded view of the first backstop and the first blocking cable according to an embodiment of the present invention.

[0025] Figure 5 This is a cross-sectional view of the first anti-sway unit (which is also the second, third, and fourth anti-sway unit) in an embodiment of the present invention.

[0026] Figure 6 This is an exploded view of the first backstop (which is also the second backstop) according to an embodiment of the present invention.

[0027] Figure 7 This is a schematic diagram of the cable system portion according to an embodiment of the present invention.

[0028] Figure 8 This is a schematic diagram of the successful recovery of a rocket using the arresting cable anti-sway system according to an embodiment of the present invention.

[0029] Explanation of reference numerals in the attached figures: 11. First arresting cable; 12. Second arresting cable; 13. Third arresting cable; 14. Fourth arresting cable; 21. First anti-sway unit; 31. First backstop; 311. Housing; 3111. Longitudinal mounting groove; 312. Cover plate; 3121. Arc-shaped hole; 3122. Eye bolt; 313. Sliding sleeve; 3131. Groove; 314. First cam; 315. Second cam; 316. Toothed rack; 32. Second backstop; 33. Linkage mechanism; 41. Cam body; 411. Mounting hole; 412. Reset hole; 42. Torsion spring; 43. Hinge shaft; 51. Cable harness; 52. Traction pin; 521. Mating hole; 53. Return plunger; 6. Double-ended steel cable; 7. Steel cable; S1, first direction; S2, second direction. Detailed Implementation

[0030] The features and exemplary embodiments of various aspects of the present invention will now be described in detail. To make the objectives, technical solutions, and advantages of the present invention clearer, the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments. It should be understood that the specific embodiments described herein are only configured to explain the present invention and to exemplify the principles of the present invention, and are not configured to limit the present invention. In addition, the structural components in the drawings are not necessarily drawn to scale. For example, the dimensions of some structural components or regions in the drawings may be enlarged for other structural components or regions to aid in the understanding of the embodiments of the present invention.

[0031] The directional terms used in the following description refer to the directions shown in the figures and are not intended to limit the specific structure of the embodiments of the present invention. In the description of the present invention, it should be noted that, unless otherwise stated, the terms "installation," "connection," and "joining" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a direct connection or an indirect connection through an intermediate medium. Those skilled in the art can understand the specific meaning of the above terms in the present invention according to the specific circumstances.

[0032] Furthermore, the terms "comprising," "including," "having," or any other variations thereof are intended to cover non-exclusive inclusion, such that a structure or component that includes a list of elements includes not only those elements but also other structural elements that are not expressly listed or inherent to the structure or component. Without further limitations, an element defined by the phrase "comprising..." does not exclude the presence of other identical elements in the article or apparatus that includes the element.

[0033] Spatial relation terms such as "below," "under," "under," "low," "above," "on," and "high" are used for descriptive convenience to explain the positioning of one element relative to a second element, indicating that these terms are intended to cover different orientations of the device, in addition to those different from those shown in the figure. Furthermore, phrases such as "one element on / below another element" can indicate that two elements are in direct contact, or that there are other elements between the two elements. In addition, terms such as "first" and "second" are also used to describe individual elements, areas, parts, etc., and should not be considered limiting. Similar terms are used throughout the description to refer to similar elements.

[0034] It will be apparent to those skilled in the art that the present invention can be practiced without requiring some of these specific details. The following description of embodiments is merely intended to provide a better understanding of the invention by illustrating examples of the invention.

[0035] The arresting cable anti-sway system provided by this invention is applied to marine rocket tethered recovery systems to prevent the arresting cable from swaying during the rocket's descent into the recovery tower. Existing tethered rocket recovery systems typically include four recovery platforms, with rails arranged in a rectangular pattern between adjacent platforms. Each rail has a trolley, and arresting cables connect the trolleys on opposite rails. A traction device is installed between adjacent recovery platforms, pulling the corresponding trolley along the rail, thereby causing the corresponding arresting cable to move synchronously. Because the span of each trolley is relatively large, and the arresting cable has no other constraints except at both ends, it is prone to significant swaying under strong external excitation conditions.

[0036] See Figure 1 and Figure 8 , Figure 1 This is a diagram showing the rocket just as it landed on the recovery tower. Figure 8This is a schematic diagram of the rocket's arresting moment. One aspect of this invention provides an arresting cable anti-sway system for a rocket tether capture system. The tether capture system includes at least four arresting cables of similar height: a first arresting cable 11, a second arresting cable 12, a third arresting cable 13, and a fourth arresting cable 14. Each arresting cable works in conjunction with the rocket hook. The first and third arresting cables 11 and 13 are meridians, while the second and fourth arresting cables 12 and 14 are parallels. During rocket capture, the first arresting cable 11 moves in the X direction, the third arresting cable 13 moves in the -X direction, the second arresting cable 12 moves in the -Y direction, and the fourth arresting cable 14 moves in the Y direction. The anti-sway system in this embodiment consists of four anti-sway units connected to four arresting cables. The four anti-sway units are respectively positioned at the intersection of the longitude and latitude of adjacent arresting cables. By simultaneously connecting two longitude and latitude arresting cables to each anti-sway unit, mutual constraints are formed, achieving the effect that the longitude restricts the latitude from moving away from the center of the rocket capture system, and the latitude restricts the longitude from moving away from the center of the rocket capture system. For example, the first arresting cable 11 can move freely in the X direction; if it moves in the -X direction, it will be restricted by the movement of the two anti-sway units connected to the second and third arresting cables, thus preventing swaying. This is especially important before the rocket returns to its final position, i.e., when each arresting cable has moved to a position close to the center of the entire capture system (…). Figure 8 The anti-sway effect of the present invention is most significant when the position shown is as indicated.

[0037] Each anti-sway unit of this invention uses two backstops in combination. Each backstop is configured to slide in one direction along the corresponding arresting cable and stop in the opposite direction. By using two backstops in combination, this invention can achieve both following and stopping in the contraction direction (towards the center of the rocket cable capture system) and expansion direction of adjacent meridians and parallels.

[0038] Specifically, the arresting cable anti-sway system of this embodiment includes at least a first anti-sway unit 21 disposed at the intersection of the first arresting cable 11 and the second arresting cable 12, a second anti-sway unit (not marked in the figure) disposed at the intersection of the second arresting cable 12 and the third arresting cable 13, a third anti-sway unit (not marked in the figure) disposed at the intersection of the third arresting cable 13 and the fourth arresting cable 14, and a fourth anti-sway unit (not marked in the figure) disposed at the intersection of the fourth arresting cable 14 and the first arresting cable 11. The first anti-sway unit 21, the second anti-sway unit, the third anti-sway unit, and the fourth anti-sway unit have the same structure. For ease of description, only the anti-sway unit 21 will be described in detail below as an example. The structures of the second anti-sway unit, the third anti-sway unit, and the fourth anti-sway unit can be referred to the relevant description of the first anti-sway unit 21, and will not be repeated here.

[0039] See also Figure 1 , Figure 2 and Figure 3The first anti-sway unit 21 includes at least a first backstop 31, a second backstop 32, and a linkage mechanism 33. The first backstop 31 is slidably mounted on the first barrier cable 11, and the second backstop 32 is slidably disposed on the second barrier cable 12. The first backstop 31 and the second backstop 32 are arranged in an alternating spatial arrangement (e.g., Figure 2 As shown, the linkage mechanism 33 connects the first backstop 31 and the second backstop 32 to enable them to move in tandem. In this embodiment, the first backstop 31 and the second backstop 32 have identical main structures and are connected by the linkage mechanism 33, allowing them to move in tandem. Specifically, the first backstop 31 is configured to move only along the first arresting cable 11 towards the center of the rocket cable capture system, and the second backstop 32 is configured to move only along the second arresting cable 12 towards the center of the rocket cable capture system.

[0040] When the first arresting cable 11 moves toward the center of the rocket cable capture system, the first backstop 31 drives the second backstop 32 to move axially along the second arresting cable 12 toward the center of the rocket cable capture system. When the first arresting cable 11 moves away from the center of the rocket cable capture system, given that the second backstop 32 has a reverse stopping function, when the first backstop 31 has a tendency to drive the second backstop 32 to move in the opposite direction, the second backstop 32 enters a stopping state and drives the first backstop 31 to stop synchronously with it, thereby preventing the first arresting cable 11 from moving away from the center of the rocket cable capture system.

[0041] When the second arresting cable 12 moves toward the center of the rocket cable capture system, the second backstop 32 drives the first backstop 31 to move axially along the first arresting cable 11 toward the center of the rocket cable capture system. When the second arresting cable 12 moves away from the center of the rocket cable capture system, given that the first backstop 31 has a reverse stopping function, when the second backstop 32 has a tendency to drive the first backstop 31 to move in the opposite direction, the first backstop 31 enters a stopping state and drives the second backstop 32 to stop synchronously, thereby preventing the second arresting cable 12 from moving away from the center of the rocket cable capture system.

[0042] In this embodiment, each backstop has a reverse locking function. To achieve this function, each backstop can adopt a structure with a cam and spring, a structure with a ball lock and spring, or an offset pendulum structure. Those skilled in the art should understand that all three embodiments described above can achieve the reverse locking function, and the specific structure can be selected according to the actual working conditions.

[0043] Furthermore, in this embodiment, the reverse locking structure can be configured as a single-unit structure or a redundant structure as needed. Those skilled in the art can select the appropriate arrangement method according to the actual working conditions and spatial layout.

[0044] In the above embodiments, the first backstop 31 and the second backstop 32 have the same structure. For ease of description, the specific structure of the first backstop 31 will be described in detail below. The structure of the second backstop 32 can be referred to the relevant description of the first backstop 31, and will not be repeated.

[0045] See also Figure 3 , Figure 4 and Figure 5 The first backstop 31 includes at least: a housing 311, a cover plate 312, a sliding sleeve 313, a first cam 314, and a second cam 315. The housing 311 is a U-shaped structure with an opening on one side, and its bottom is provided with a longitudinal mounting groove 3111 parallel to the side of the U-shaped structure. The cover plate 312 is fixedly installed at the open end of the housing 311 and forms a receiving cavity with the housing 311. The sliding sleeve 313 is a cylindrical structure and is fixedly installed in the longitudinal mounting groove 3111. It has symmetrical grooves 3131 in the radial direction. The first cam 314 and the second cam 315 are rotatably pressed against the radial sides of the sliding sleeve 313 by a torsion spring 42, and are at least partially embedded in the grooves 3131 of the sliding sleeve 313, thereby forming a rope passage gap for the first blocking cable 11 to pass through.

[0046] The first cam 314 and the second cam 315 have the same structure and are arranged opposite each other on both sides of the sliding sleeve 313. In order to achieve unidirectional sliding of the first backstop 31 relative to the first blocking cable 11, the first cam 314 and the second cam 315 can be configured as follows: When the first backstop 31 slides along the first arresting cable 11 in the first direction, the first cam 314 and the second cam 315, driven by the friction of the first arresting cable 11, overcome the elastic force of the torsion spring 42 and rotate away from the first arresting cable 11, increasing the cable clearance to allow the first backstop to slide along the first arresting cable 11 in the first direction. The first direction is the direction toward the center of the rocket cable capture system.

[0047] When the first backstop 31 slides along the second direction of the first arresting cable 11, the first cam 314 and the second cam 315 rotate towards the first arresting cable 11 under the action of the torsion spring 42, contacting and rubbing against the first arresting cable 11. Driven by the frictional force of the first arresting cable 11, the gap between the cables decreases and the first arresting cable 11 is clamped, thereby preventing the first backstop 31 from sliding along the second direction of the first arresting cable 11. The second direction is the direction away from the center of the rocket cable capture system, and the second direction is opposite to the orientation of the first direction.

[0048] In one embodiment, the first cam and / or the second cam includes at least a cam body 41 and a hinge shaft 43. The end of the cam body 41 furthest from the arresting cable is provided with a double-layered clamping plate, and a torsion spring 42 is housed between the upper and lower clamping plates. The hinge shaft 43 passes through the upper clamping plate, the torsion spring 42, and the lower clamping plate and is rotatably connected to the inner wall of the housing side. The torsion spring 42 is clamped between the inner wall of the housing side and the cam body, and the cam body abuts against the arresting cable under the elastic compressive force of the torsion spring. In this embodiment, the backstop can swing around the hinge shaft 43 as its rotation center. When no external force is applied, the torsion spring 42 is in its initial position (i.e., the working position). When an external force pulls the cam body 41 to rotate around the hinge shaft 43 in a direction away from the first arresting cable, the inner wall of the cam body 41 compresses the torsion spring 42, causing it to undergo elastic compression deformation. When the external driving force disappears, the torsion spring 42 returns to its original position by its own elastic restoring force and drives the cam body 41 back to the working position, thus restoring the backstop to its working state.

[0049] Furthermore, the arresting cable anti-sway system of this embodiment also includes a pulling unit and a positioning unit. The pulling unit is used to apply a driving force to the cam body in the backstop, causing it to rotate away from the first arresting cable. The positioning unit is used to restrict the cam body in its current position after rotation. Specifically, the pulling unit acts on the cam body at a position away from the hinge axis and the center of the rocket cable capture system to apply a driving force. After the pulling unit drives the cam body to rotate around the hinge axis to the release position, the positioning unit locks the cam body in the release position so that the backstop can slide bidirectionally along the corresponding arresting cable. The pulling unit can be a rope. The positioning unit is available in manual and automatic forms: the manual positioning mechanism can use simple means such as clamps or wire binding; the automatic positioning mechanism achieves automatic locking after positioning through internal structural design.

[0050] See also Figure 3 , Figure 4 , Figure 6 and Figure 7In one embodiment, the arresting cable anti-sway system of the present invention further includes a release mechanism. The release mechanism in this embodiment includes at least a cable system 51, a traction pin 52, and a reset plunger 53, as well as a mounting hole 411 and a reset hole 412 disposed on the cam body 41. The mounting hole 411 and the reset hole 412 are located on the side of the cam body 41 away from the hinge axis 43, with the reset hole 412 closer to the center of the arresting cable and rocket cable capture system than the mounting hole 411. The mounting hole 411 is used for the traction pin 52 to pass through and be fixedly installed, and the reset hole 412 is used for the reset plunger 53 to pass through. In this embodiment, the traction pin 52 acts as an external driving force component, with one end extending out of the cover plate 312 and connected to the cable system 51, so that the cable system 51 can pull the traction pin 52 to drive the cam body 41 to rotate about the hinge axis 43 in a direction away from the arresting cable. To accommodate the movement trajectory of the traction pin 52, the cover plate 312 is provided with an arc-shaped hole 3121 that matches the rotation trajectory of the traction pin 52. One end of the traction pin 52 passes through the mounting hole 411 and the arc-shaped hole 3121 and is connected to the cable system 51. In this embodiment, the reset hole 412 is located on a circumference with a set radius centered on the hinge shaft 43. One end of the reset plunger 53 is mounted on the housing 311, and the other end elastically abuts against the cam body 41 under its own elastic force. The axial projection of the reset plunger 53 onto the cam body 41 falls on this circumference. In this embodiment, the reset plunger has a built-in elastic reset element. Under normal conditions, the spherical surface at the top of the reset plunger continuously and elastically abuts against the lower end face of the cam body 41.

[0051] The method for releasing each anti-sway unit using the release mechanism of this embodiment is as follows: the traction pin 52 is pulled by the cable 51 to drive the cam body 41 to rotate away from the blocking cable with the hinge shaft 43 as the center. When the axis of the reset plunger 53 is aligned with the center line of the reset hole 412, the reset plunger 53 is elastically reset and can be inserted into the reset hole 412 to keep the cam body 41 in the released position, thereby maintaining the released state of the corresponding anti-sway unit.

[0052] The release mechanism in the above embodiments can release in situ or remotely by pulling with a steel cable. Furthermore, it can simultaneously release two backstops (four cams) in a set of anti-sway units using a single steel cable and cable system, making it convenient and efficient to operate. For example, see... Figure 2 , Figure 3 and Figure 7The cable system 51 of the two backstops can be connected to the double-ended steel cable 6. The other side of the double-ended steel cable 6 is connected to the steel cable 7. The other side of the steel cable 7, away from the double-ended steel cable 6, is connected to the angled fixed position of the recovery tower. The operator can stand on the platform at the angled fixed position and apply a pulling force in the direction shown by F, pulling the steel cable 7 through the double-ended steel cable 6 to drive the cable system 51 to pull the cam body to the release position, thereby releasing the anti-sway device. In this embodiment, by applying an external driving force to the double-ended steel cable 6 through the steel cable 7, the double-ended structure of the double-ended steel cable 6 can be used to simultaneously pull the two cable systems 51, achieving simultaneous release of the two backstops.

[0053] In the above embodiments, at least one weight-reducing hole can be provided on the cam body to reduce weight.

[0054] See Figure 3 and Figure 6 In one embodiment, the portion of the traction pin 52 extending beyond the cover plate 312 is provided with a mating hole 521. An eye bolt 3122 is provided on the outer surface of the cover plate 312. The central axis of the eye bolt 3122's eye hole is collinear with the central axis of the mating hole 521 of the traction pin 52. The cable system 51 passes through the eye bolt 3122's eye hole and connects to the mating hole 521 of the traction pin 52. In this embodiment, the central axis of the eye hole and the central axis of the mating hole are arranged collinearly so that the force exerted by the cable system on the traction pin is transmitted along the common axis of the two holes. In this embodiment, the traction pin 52 is installed inside the mounting hole 411 of the cam body 41. The cable system 51 pulls and drives the cam body 41 to rotate about the hinge axis in a direction away from the blocking cable, with a rotation angle of 15-20°. See Figure 4 and Figure 5 In any of the above embodiments, the portions of the first cam 315 and the second cam 316 embedded in the groove 3131 are provided with teeth 316. Each arresting cable has several annular protrusions evenly spaced along its own axial direction on its outer circumferential surface. The teeth 316 mesh with the protrusions on the first arresting cable 11 to allow the first backstop to slide along the first direction S1 of the first arresting cable 11 and to prevent the first backstop from sliding along the second direction S2 of the first arresting cable 11. This embodiment, through the cooperation of the teeth on the cams and the arresting cable with annular protrusions, further enhances the locking effect of the backstop in the reverse direction (second direction), significantly improving the anti-sway effect.

[0055] To further enhance the locking effect of the backstop, the spacing between the annular protrusions located near the center of the rocket cable capture system on each arresting cable can be reduced, for example, to 200mm-300mm.

[0056] See Figure 3In any of the above embodiments, the linkage mechanism 33 is a spherical bearing assembly, and the first and second backstops are assembled together via the spherical bearing assembly. The main structures of the first and second backstops are identical, but different interface structures are provided on the outer side of the top cover to facilitate connection via the spherical bearing assembly. The spherical bearing assembly of this embodiment allows rotation and oscillation between the first and second backstops to adapt to angular changes before and after the adjacent arresting cable captures the rocket.

[0057] After assembly, the anti-sway system and the cable-stayed arresting system of this invention remain in a reverse-stop state. During the capture of the rocket by the cable-stayed arresting system, that is, as each arresting cable moves towards the rocket stage (the center position of the rocket cable-stayed arresting system), each cam slides smoothly with its corresponding arresting cable. When the arresting cable is disturbed by external forces and sways in the opposite direction, each cam restricts the reverse sliding of the corresponding arresting cable, thereby limiting the reverse swaying of each arresting cable.

[0058] Once the arresting cable system has unloaded the rocket, pulling the steel cables will release the backstops without restricting the reset of the arresting cables to their initial state.

[0059] The above embodiments can be combined with each other and have corresponding technical effects.

[0060] Another aspect of the present invention provides a method for preventing swaying of the arresting cable in a rocket cable-based capture system. Using the arresting cable sway prevention system in any of the above embodiments to prevent swaying during the rocket cable-based capture process includes at least the following steps: Step 1: Install the rocket arresting cable system in place, making the first arresting cable parallel to the third arresting cable, the second arresting cable parallel to the fourth arresting cable, and the first arresting cable intersecting with the second and fourth arresting cables respectively, and the third arresting cable intersecting with the second and fourth arresting cables respectively. Step 2: Install a first backstop on the first barrier cable and a second backstop on the second barrier cable. Slide the first and second backstops to the position where the first and second barrier cables intersect, and connect the first and second backstops through a linkage mechanism to form a first anti-sway unit. Step 3: Referring to the method in Step 2, set up a second anti-sway unit at the intersection of the second and third barrier cables, a third anti-sway unit at the intersection of the third and fourth barrier cables, and a fourth anti-sway unit at the intersection of the fourth and first barrier cables. Step 4: Configure the first and second backstops in each anti-sway unit to move only along the corresponding arresting cable toward the center position of the rocket cable capture system. Step 5: When the rocket stage lands in the area enclosed by the first arresting cable, the second arresting cable, the third arresting cable, and the fourth arresting cable are controlled to open and drive the first arresting cable, the second arresting cable, the third arresting cable, and the fourth arresting cable to move synchronously toward the center of the rocket cable capture system. Each arresting cable drives the backstop on the adjacent arresting cable to move synchronously. Step Six: When the rocket descends to a height where the rocket hook is close to the arresting cable, the tail of the rocket approaches the surface of the recovery ship. The turbulence caused by the backflow of the engine exhaust acts on each arresting cable. Each arresting cable is prevented from swaying away from the center of the rocket tether capture system by the backstop on the adjacent arresting cable, so that each arresting cable always moves towards the center of the rocket tether capture system until the rocket hook is successfully engaged.

[0061] Furthermore, each backstop is equipped with a release mechanism, which locks the position of the cam after release, thereby enabling bidirectional sliding between the backstop and the arresting cable. After the cable-stayed capture system unloads the rocket, pulling the steel cable will release each backstop without restricting the reset of the arresting cable to its initial state.

[0062] The release mechanism in this embodiment can release in situ or remotely by pulling with a steel cable. Furthermore, it can simultaneously release the four cams of the backstop assembly (anti-sway unit) with a single steel cable, thus exhibiting excellent operability.

[0063] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. An arresting cable anti-sway system for rocket cable-stayed capture systems, characterized in that, At least including: A first anti-sway unit is installed at the intersection of the first and second barrier cables; a second anti-sway unit is installed at the intersection of the second and third barrier cables; a third anti-sway unit is installed at the intersection of the third and fourth barrier cables; and a fourth anti-sway unit is installed at the intersection of the fourth and first barrier cables. The first anti-sway unit includes at least a first backstop, a second backstop, and a linkage mechanism; the first backstop is slidably mounted on the first barrier cable, the second backstop is slidably disposed on the second barrier cable, the first backstop and the second backstop are arranged in an alternating manner in space, and the linkage mechanism is connected between the first backstop and the second backstop to enable the first backstop and the second backstop to be linked together. The first backstop is configured to move only along the first arresting cable toward the center of the rocket cable capture system; the second backstop is configured to move only along the second arresting cable toward the center of the rocket cable capture system. The first arresting cable moves toward the center position of the rocket cable capture system, and through the first backstop, drives the second backstop to move along the axis of the second arresting cable toward the center position of the rocket cable capture system. The second arresting cable moves toward the center of the rocket cable capture system, and through the second backstop, the first backstop moves along the axis of the first arresting cable toward the center of the rocket cable capture system.

2. The arresting cable anti-sway system according to claim 1, characterized in that, The first check valve and the second check valve have the same structure; The first backstop includes at least: a housing, a cover plate, a sliding sleeve, a first cam, and a second cam; the housing is a U-shaped structure with an opening on one side, and its bottom is provided with a longitudinal mounting groove parallel to the side of the U-shaped structure; the cover plate is fixedly installed at the opening end of the housing and surrounds the housing to form a receiving cavity; the sliding sleeve is a cylindrical structure, fixedly disposed in the longitudinal mounting groove, and has symmetrical grooves in its radial direction; the first cam and the second cam are rotatably pressed against the radial sides of the sliding sleeve by a torsion spring, and are at least partially embedded in the grooves of the sliding sleeve, thereby forming a rope passage gap for the arresting cable to pass through; The first cam and the second cam are configured as follows: When the first backstop slides along the first direction of the first blocking cable, the first cam and the second cam, driven by the friction of the first blocking cable, overcome the elastic force of the torsion spring and rotate away from the first blocking cable, thereby increasing the rope clearance. When the first backstop slides along the second direction of the first blocking cable, the first cam and the second cam rotate toward the direction of the first blocking cable under the action of the torsion spring, contact and rub against the first blocking cable, and reduce the rope gap and clamp the first blocking cable under the friction force of the first blocking cable. The first direction is toward the center of the rocket tether capture system, and the second direction is opposite to the first direction.

3. The arresting cable anti-sway system according to claim 2, characterized in that, The first cam and / or the second cam includes at least a cam body and a hinge shaft; the end of the cam body away from the arresting cable is provided with a sandwich-type upper and lower double-layer clamping plate, the torsion spring is accommodated between the upper and lower double-layer clamping plates, and the hinge shaft passes through the upper clamping plate, the torsion spring and the lower clamping plate and is rotatably connected to the inner wall of the housing; The torsion spring is clamped between the inner wall of the housing side and the cam body, and the cam body abuts against the arresting cable under the elastic compression force of the torsion spring.

4. The arresting cable anti-sway system according to claim 3, characterized in that, It also includes a pulling unit and a positioning unit; the pulling unit acts on the cam body at a position away from the hinge axis and the center of the rocket cable capture system; after the cam body is rotated around the hinge axis to the release position by the pulling unit, the positioning unit locks the cam body in the release position.

5. The arresting cable anti-sway system according to claim 3, characterized in that, It also includes a release mechanism, which includes at least a cable system, a traction pin, and a reset plunger, as well as a mounting hole and a reset hole disposed on the cam body; the mounting hole and the reset hole are disposed on the side of the cam body away from the hinge axis, and the reset hole is closer to the center of the arresting cable and rocket cable capture system than the mounting hole; The cover plate is provided with an arc-shaped hole that follows the same rotation trajectory as the traction pin. The traction pin passes through the mounting hole and the arc-shaped hole and is then connected to the cable system. The reset hole is located on a circumference with a set radius centered on the hinge shaft; one end of the reset plunger is installed on the housing, and the other end elastically abuts against the cam body under its own elastic force, and the axial projection of the reset plunger on the cam body falls on the circumference. By pulling the traction pin through the cable system, the cam body rotates around the hinge axis in a direction away from the blocking cable. When the axis of the reset plunger is collinear with the center line of the reset hole, the reset plunger can be inserted into the reset hole to maintain the released state.

6. The arresting cable anti-sway system according to claim 5, characterized in that, The portion of the traction pin extending beyond the cover plate is provided with a mating hole, and the outer surface of the cover plate is provided with a lifting eye screw. The central axis of the lifting eye screw's lifting eye hole is collinear with the central axis of the mating hole of the traction pin. The cable passes through the eyelet hole of the eyelet screw and connects to the mating hole of the traction pin.

7. The arresting cable anti-sway system according to claim 2, characterized in that, The first cam and the second cam are provided with toothed sections in the portion of the groove. Each barrier cable has several annular protrusions at equal intervals along its own axial direction on its outer peripheral surface. The toothed sections mesh with the protrusions to allow the first backstop to slide along the first direction of the first barrier cable and to prevent the first backstop from sliding along the second direction of the first barrier cable.

8. The arresting cable anti-sway system according to claim 1, characterized in that, The linkage mechanism is a spherical bearing assembly; the first backstop and the second backstop are assembled together through the spherical bearing assembly, which allows rotation and oscillation between the first backstop and the second backstop.

9. The arresting cable anti-sway system according to any one of claims 1 to 8, characterized in that, The first anti-sway unit, the second anti-sway unit, the third anti-sway unit, and the fourth anti-sway unit have the same structure.

10. A method for preventing swaying of arresting cables in a rocket cable-stayed capture system, characterized in that, Using the arresting cable anti-sway system according to any one of claims 1 to 9 to achieve anti-sway during rocket cable capture, at least the following steps are included: Step 1: Install the rocket arresting cable system in place, making the first arresting cable parallel to the third arresting cable, the second arresting cable parallel to the fourth arresting cable, and the first arresting cable intersecting with the second and fourth arresting cables respectively, and the third arresting cable intersecting with the second and fourth arresting cables respectively. Step 2: Install a first backstop on the first barrier cable and a second backstop on the second barrier cable. Slide the first and second backstops to the position where the first and second barrier cables intersect, and connect the first and second backstops through a linkage mechanism to form a first anti-sway unit. Step 3: Referring to the method in Step 2, set up a second anti-sway unit at the intersection of the second and third barrier cables, a third anti-sway unit at the intersection of the third and fourth barrier cables, and a fourth anti-sway unit at the intersection of the fourth and first barrier cables. Step 4: Configure the first and second backstops in each anti-sway unit to move only along the corresponding arresting cable toward the center position of the rocket cable capture system. Step 5: When the rocket stage lands in the area enclosed by the first arresting cable, the second arresting cable, the third arresting cable, and the fourth arresting cable are controlled to open and drive the first arresting cable, the second arresting cable, the third arresting cable, and the fourth arresting cable to move synchronously toward the center of the rocket cable capture system. Each arresting cable drives the backstop on the adjacent arresting cable to move synchronously. Step Six: When the rocket descends to a height where the rocket hook is close to the arresting cable, the tail of the rocket approaches the surface of the recovery ship. The turbulence caused by the backflow of the engine exhaust acts on each arresting cable. Each arresting cable is prevented from swaying away from the center of the rocket tether capture system by the backstop on the adjacent arresting cable, so that each arresting cable always moves towards the center of the rocket tether capture system until the rocket hook is successfully engaged.

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