A catapult release and recovery mechanism for tethered satellites with reusable unlocking and locking, and its working method.

Abstract

This invention discloses a catapult release and recovery mechanism and its working method for tethered satellites with reusable locking and unlocking, belonging to the field of tethered satellite release and recovery. The invention includes a separation catapult docking assembly and a satellite sub-satellite. The separation catapult docking assembly includes a catapult sleeve, a locking mechanism, and a satellite sub-satellite connector. The catapult sleeve is a two-section inner and outer sliding connection, providing initial kinetic energy to the satellite sub-satellite through a compression spring. The locking mechanism is installed inside the catapult sleeve. One end of the satellite sub-satellite connector is connected to the satellite sub-satellite, and the other end slides with the locking mechanism to complete the locking / unlocking action of the satellite sub-satellite. This invention eliminates the need for additional control components to control the locking and unlocking of the mechanism, effectively reducing its complexity and improving its overall reliability.

Description

Technical Field

[0001] This invention belongs to the field of tethered satellite release and recovery, specifically relating to an ejection release and recovery mechanism for tethered satellites with repeatable unlocking and locking, and its working method. Background Technology

[0002] Tethered satellite systems are a novel type of spaceflight system with enormous application potential in areas such as space debris cleanup, artificial gravity, and deep space exploration. Tethered satellites utilize long, flexible tethers to perform wide-ranging, inter-orbital space maneuvers, with continuous maneuvers that do not require repeated orbital changes, making them highly versatile in space.

[0003] The on-orbit flight of tethered satellites mainly includes three phases: release, hold, and recovery. Reliable release and recovery are the prerequisites and foundation for achieving their orbital maneuvering missions, involving issues such as initial separation, release, recovery, and docking locking. In the initial separation phase, a reliable ejection mechanism is needed to provide kinetic energy to the payload. Simultaneously, the ejection release mechanism must also have the functions of guiding docking and locking to effectively recover the tethered satellite. For example, patent application CN117087880A discloses a low-impact ejection mechanism for the release and recovery of tethered satellites, including at least one ejection assembly; the ejection assembly includes a satellite sub-satellite, an ejection module, a locking module, a tether deployment and retrieval module, and a speed limiting module. This invention enables the ejection and recovery locking of a satellite sub-satellite, and can be repeatedly used in ground simulation experiments for the release and recovery of tethered satellites. It also facilitates adjusting the sub-satellite's attitude for successful recovery, ejecting the sub-satellite at a specific speed without generating significant resistance during recovery locking. Furthermore, the control system can autonomously and repeatedly perform ejection-recovery experiments. The speed-limiting module automatically locks based on a set acceleration value to prevent impact during sub-satellite release. However, its components are numerous and its structure is complex, especially the additional unlocking motor installed at the ejection separation assembly, which significantly impacts the overall system reliability. Therefore, there is a need to develop a simple and reliable ejection and recovery mechanism that eliminates the need for an unlocking motor. Summary of the Invention

[0004] This invention provides a catapult release and recovery mechanism for tethered satellites with reusable unlocking and locking, and its working method. It eliminates the need for additional control components to control the unlocking and locking of the mechanism, effectively reducing the complexity of the mechanism and improving the overall reliability of the mechanism.

[0005] To achieve the above objectives, the present invention adopts the following technical solution:

[0006] A catapult release and recovery mechanism for repeatedly unlocking and locking a tethered satellite includes a separation catapult docking assembly and a satellite sub-satellite; the separation catapult docking assembly is used to control the unlocking / locking of the satellite sub-satellite.

[0007] The separation ejection docking assembly includes a satellite connector, an ejection sleeve, and a locking mechanism. The ejection sleeve is a two-section inner and outer sliding connection, which provides initial kinetic energy to the satellite through a spring. The locking mechanism is installed inside the ejection sleeve. One end of the satellite connector is connected to the satellite, and the other end slides with the locking mechanism to complete the locking / unlocking action of the satellite.

[0008] The locking mechanism includes two locking seats, one upper and one lower. Each locking seat has a guide groove. The guide groove formed after the two locking seats are aligned at a certain angle cooperates with the limiting protrusion on the sub-star connector to realize the function of automatic locking and unlocking.

[0009] The guide groove is serrated. The guide groove of the upper locking seat has two notches at the top compared to the guide groove of the lower locking seat, which facilitates the limiting protrusion of the docking rod to enter / leave the guide groove through the notches. When the limiting protrusion on the docking rod touches the lower guide groove, it will rotate at a certain angle under the action of the guide groove, and thus be blocked by the part of the upper guide groove without notches to achieve the locking function. Repeating the same action, the limiting protrusion will rotate to the part with notches, thereby releasing the docking rod and achieving the unlocking function.

[0010] The sub-star connector includes a docking plate and a docking rod. One end of the docking rod is provided with a limiting protrusion, which cooperates with the guide groove of the upper and lower locking seats, and the other end cooperates with the docking plate to connect the sub-star.

[0011] Beneficial effects: This invention provides a repeatedly unlockable and lockable ejection release and recovery mechanism for tethered satellites and its working method. A repeatedly unlockable and lockable locking device is designed to work in conjunction with the tether recovery action to achieve ejection release and recovery locking of the satellite. No additional motor is required to control the locking device. It can be repeatedly used in release and recovery experiments for tethered satellites. The separation ejection docking assembly can eject the satellite at a certain speed without generating significant resistance during recovery and locking. Furthermore, the ejection-recovery experiment can be autonomously and repeatedly performed by controlling only the stepper motor of the take-up and take-down line. The locking device of this invention can automatically lock after the satellite is recovered to its designated position to prevent the satellite from detaching and affecting the experimental results. Attached Figure Description

[0012] Figure 1 This is an exploded view of the ejection mechanism separation ejection docking component module in an embodiment of the present invention;

[0013] Figure 2 This is a cross-sectional view of the ejection mechanism separation ejection docking component module in an embodiment of the present invention;

[0014] Figure 3 This is a schematic diagram of the ejection mechanism sleeve limiting cover in an embodiment of the present invention.

[0015] Figure 4This is a schematic diagram of the locking seat on the ejection mechanism in an embodiment of the present invention;

[0016] Figure 5 This is a schematic diagram of the lower locking seat of the ejection mechanism in an embodiment of the present invention;

[0017] Figure 6 This is a schematic diagram a of the working process of the ejection mechanism locking seat module in an embodiment of the present invention;

[0018] Figure 7 This is a schematic diagram (b) of the working process of the ejection mechanism locking seat module in an embodiment of the present invention;

[0019] Figure 8 This is a schematic diagram of the working process of the ejection mechanism locking seat module in an embodiment of the present invention (c).

[0020] Figure 9 This is a schematic diagram (d) of the working process of the ejection mechanism locking seat module in an embodiment of the present invention;

[0021] Figure 10 This is a schematic diagram e of the working process of the ejection mechanism locking seat module in an embodiment of the present invention;

[0022] Figure 11 This is a schematic diagram of the assembly of the ejection mechanism docking guide cone, upper locking seat and fixing sleeve in an embodiment of the present invention;

[0023] Figure 12 This is a schematic diagram of the assembly of the lower locking seat and the fixed sleeve of the ejection mechanism in an embodiment of the present invention;

[0024] In the diagram, 1 is the inner sleeve, 2 is the lower locking seat, 3 is the fixed sleeve, 4 is the upper locking seat, 5 is the docking guide cone, 6 is the sleeve limiting cover, 7 is the outer sleeve, 8 is the docking rod, 9 is the docking plate, 10 is the support plate, and 11 is the spring. Detailed Implementation

[0025] The present invention will now be described in detail with reference to the accompanying drawings and specific embodiments:

[0026] like Figure 1 and Figure 2 As shown, a catapult release and recovery mechanism for repeatedly unlocking and locking tethered satellites includes an inner sleeve 1, a locking mechanism, a sleeve limiting cover 6, an outer sleeve 7, a docking rod 8, a docking plate 9, and a spring 11. The outer sleeve 7 is located outside the inner sleeve 1 and is slidably connected to the inner sleeve 1. The locking mechanism is located inside the inner sleeve 1. One end of the docking rod 8 is connected to the satellite by the docking plate 9, and the other end of the docking rod 8 is connected to the locking mechanism to achieve locking and unlocking.

[0027] The inner sleeve 1 has six evenly distributed M3 threaded holes at its base for connection to the bottom support plate 10. The top of the inner sleeve 1 has four M2 threaded holes for connection to the sleeve limiting cap 6. The inner side of the outer sleeve 7 has a step that engages with the sleeve limiting cap 6 to limit the maximum ejection displacement. The upper part of the sleeve limiting cap 6 is tapered to facilitate the entry of the docking rod 8. It has four through holes in the circumference and is connected to the top of the inner sleeve 1 by M2 screws. The diameter of the sleeve limiting cap 6 is slightly larger than the outer diameter of the inner sleeve and equal to the inner diameter of the outer sleeve 7. The inner diameter of the step of the outer sleeve 7 is equal to the outer diameter of the inner sleeve 1. This engagement enables the function of limiting the maximum displacement of the sleeve. The spring 11 is fitted onto the outside of the outer sleeve 7. Grooves are provided at the bottom of the inner sleeve 1 and the top of the outer sleeve 7 to fix the spring.

[0028] The locking mechanism includes a lower locking seat 2, a fixed sleeve 3, an upper locking seat 4, and a docking guide cone 5. A guide groove is formed between the lower locking seat 2 and the upper locking seat 4. The guide groove is serrated, and the lower locking seat 2 and the upper locking seat 4 are aligned at a certain angle. The serrated lower end of the guide groove of the upper locking seat 4 is provided with two symmetrical notches, which allow the limiting protrusion of the docking rod to enter the guide groove through the notches. When the limiting protrusion on the docking rod touches the lower guide groove, it will rotate at a certain angle under the action of the guide groove, and thus be blocked by the part of the upper guide groove without notches to achieve the locking function. Repeating the same action, the limiting protrusion will rotate to the part with notches, thereby releasing the docking rod and achieving the unlocking function.

[0029] like Figure 11-12 As shown, the lower locking seat 2, the upper locking seat 4, and the docking guide groove need to be placed at a specific angle to achieve their respective functions. Therefore, a hexagonal step is designed, which cooperates with the internal hexagonal step of the fixed sleeve 3 to achieve a specific angle placement. The docking guide cone 5 and the upper locking seat 4 are placed in the internal hexagonal groove on the upper part of the fixed sleeve 3, and the lower locking seat 2 is placed in the internal hexagonal groove on the lower part of the fixed sleeve 3. After the four parts of the locking mechanism are assembled, they form a cylindrical module that can be directly placed in the cylindrical cavity of the inner sleeve 1.

[0030] The working method of the above-mentioned ejection release and recovery mechanism specifically includes the following steps:

[0031] 1. Initial state: such as Figure 6 As shown, the ejector sleeve compresses the spring, and the limiting protrusion of the docking rod 8 is locked in the guide groove of the upper locking seat 4. The locking seat locks the sub-star, and the mechanism is in the initial ejection state. After the mechanism is powered on, the system self-test program is run. If the self-test passes, the next step is performed.

[0032] 2. Ejection Separation Phase: The system sends a command to pull back the tether, causing the launcher to further compress the ejection sleeve. Figure 7 As shown, the limiting protrusion of the docking rod 8 disengages from the upper locking seat 4 and contacts the guide groove of the lower locking seat 2, as... Figure 8 As shown, after contact, the limiting protrusion of the docking rod 8 continues to slide diagonally downwards to the bottom of the guide groove of the lower locking seat 2. At this time, the spring reaches its maximum compression. The system executes the judgment program. After determining that the pullback is in place, the ejection command is executed, the tether is released, and the sub-star and docking rod separate outwards under the action of the spring, as shown. Figure 9 As shown, after the limiting protrusion of the docking rod 8 contacts the guide groove of the upper locking seat 4, it continues to rotate and slide outward, eventually sliding out of the locking seat from the guide groove notch of the upper locking seat 4. Figure 10 The ejection separation process is complete; proceed to the next step.

[0033] 3. During the release and deployment process, the satellite leaves the ejection mechanism at a certain speed. The speed is gradually reduced by the motor control, and the satellite stops moving when the tether reaches the predetermined release length without rebounding.

[0034] 4. After the tethered rope has been stationary for a period of time, the satellite is pulled back to the separation ejection docking assembly by retrieval of the tethered rope. The docking rod 8 enters the upper locking seat 4 through the docking guide cone 5. Similar to step 2, the limiting protrusion of the docking rod 8 slides in the locking seat and finally gets stuck on the side of the upper locking seat 4 without a notch, thus realizing the retrieval docking function.

[0035] 5. Steps 2-4 can be repeated multiple times to achieve repeated unlocking and locking of the tethered satellite ejection and recovery mechanism.

[0036] The above description is only a preferred embodiment of the present invention. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the principle of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. A catapult release and recovery mechanism for repeatedly unlocking and locking tethered satellites, characterized in that, The system includes a separation ejection docking assembly and a sub-satellite. The separation ejection docking assembly includes an ejection sleeve, a locking mechanism, and a sub-satellite connector. The ejection sleeve is a two-section inner and outer sliding connection, providing initial kinetic energy to the sub-satellite through a compression spring. The locking mechanism is installed inside the ejection sleeve. One end of the sub-satellite connector is connected to the sub-satellite, and the other end slides with the locking mechanism to complete the locking / unlocking action of the sub-satellite. The locking mechanism includes upper and lower locking seats, each with a guide groove. The guide groove formed by aligning the two locking seats at a certain angle cooperates with the limiting protrusion on the sub-satellite connector to achieve automatic locking and unlocking. The guide groove is serrated, and the lower end of the serrated guide groove of the upper locking seat has two symmetrical notches for the inlet and outlet of the limiting protrusion.

2. The ejection release and recovery mechanism for repeatedly unlocking and locking a tethered satellite according to claim 1, characterized in that, The locking mechanism includes a docking guide cone and a fixed sleeve. The docking guide cone has an intersecting step that cooperates with the internal hexagonal step of the fixed sleeve. The docking guide cone and the upper locking seat are placed in the internal hexagonal groove on the upper part of the fixed sleeve, and the lower locking seat is placed in the internal hexagonal groove on the lower part of the fixed sleeve.

3. The ejection release and recovery mechanism for repeatedly unlocking and locking a tethered satellite according to claim 1, characterized in that, The sub-satellite connector includes a docking plate and a docking rod. One end of the docking rod is provided with a limiting protrusion, and the other end cooperates with the docking plate to connect to the sub-satellite.

4. The ejection release and recovery mechanism for repeatedly unlocking and locking a tethered satellite according to claim 1, characterized in that, The ejection sleeve includes an inner sleeve, an outer sleeve, and a sleeve limiting cap. The outer sleeve is located outside the inner sleeve and is slidably connected to the inner sleeve. The top of the inner sleeve is connected to the sleeve limiting cap. A step is provided on the inner side of the outer sleeve to cooperate with the sleeve limiting cap. The diameter of the sleeve limiting cap is larger than the outer diameter of the inner sleeve and equal to the inner diameter of the outer sleeve. The inner diameter of the step on the outer sleeve is equal to the outer diameter of the inner sleeve, which cooperates to limit the maximum ejection displacement of the sleeve.

5. The ejection release and recovery mechanism for repeatedly unlocking and locking a tethered satellite according to claim 4, characterized in that, The outer sleeve is fitted with a spring, and the bottom of the inner sleeve and the top of the outer sleeve are provided with grooves for fixing the spring.

6. The method of operation of the ejection release and recovery mechanism for repeatedly unlocking and locking a tethered satellite as described in any one of claims 1-5, characterized in that, Includes the following steps: S1: Initial state: The ejector sleeve compresses the spring, the limiting protrusion of the sub-star connector is stuck in the guide groove, the locking mechanism locks the sub-star, and the mechanism is in the initial ejection state; S2: Ejection Separation Stage: The pullback rope drives the sub-star to further compress the ejection sleeve. The limiting protrusion disengages from the upper locking seat and contacts the guide groove of the lower locking seat. After contact, the limiting protrusion continues to slide diagonally downward to the bottom of the guide groove. At this time, the spring reaches its maximum compression, executes the ejection command, releases the rope, and the sub-star and sub-star connector separate outward under the action of the spring. After the limiting protrusion contacts the guide groove of the upper locking seat, it continues to slide outward while rotating, and finally slides out of the locking seat from the notch of the guide groove of the upper locking seat. The ejection separation process is completed. S3: Release and deployment process: The satellite leaves the ejection mechanism at a certain speed, and its speed gradually decreases through the motor control. It stops moving and does not rebound when the tether reaches the predetermined release length. S4: Recovery Phase: After the tether remains stationary for a period of time, the satellite is pulled back to the separation ejection docking assembly by tether recovery. One end of the satellite connector enters the locking seat, the limiting protrusion enters the guide groove, the limiting protrusion slides in the locking seat, and finally gets stuck on the side of the upper locking seat without a notch, thus realizing the recovery docking function.

7. The operating method of the ejection release and recovery mechanism for repeatedly unlocking and locking a tethered satellite according to claim 6, characterized in that, Steps S2-S4 can be repeated as required.

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