A rocket recovery device based on vertical multi-hook layout and a hydrodynamic rocket simulation verification system thereof

Abstract

This invention discloses a rocket recovery device based on a vertical multi-hook layout and its hydrodynamic rocket simulation and verification system. The device comprises a rocket body, a hook mechanism, an actuation mechanism, a recovery device body, and a hydrodynamic simulation and verification section. The hook body is arranged vertically along the rocket's axis and stored on the outside of the rocket body. After the recovery procedure is initiated, the comb rod is unlocked by an electric cylinder and rapidly ejected under the action of a torsion spring, cooperating with the arresting cable to achieve hooking and capture. An inductive proximity sensor is used to detect the arresting cable's hooking status. A buffer mechanism is used to absorb the rocket's remaining kinetic energy, achieving deceleration and stable recovery. The hydrodynamic simulation and verification section drives the rocket body through a water supply device to simulate the takeoff, approach, capture, and recovery processes, used for repeated testing and verification of the recovery device. This invention can improve recovery robustness and hooking success rate, reduce dependence on attitude and landing accuracy, and has the advantages of low testing cost and easy repeatability.

Description

Technical Field

[0001] This invention pertains to rocket recovery devices and their simulation and verification systems, specifically relating to a rocket recovery device based on a vertical multi-hook layout and its hydrodynamic rocket simulation and verification system. Background Technology

[0002] Reusable launch vehicle recovery technology is one of the key technologies for reducing space launch costs and improving launch efficiency. Currently, the mainstream recovery methods mainly include powered vertical landing recovery, parachute recovery, and arrested recovery. Among them, arrested recovery has become one of the important technological directions in the field of rocket recovery because it does not require complex landing support structures on the rocket body and has relatively lower requirements for the precision of rocket attitude and velocity control.

[0003] Existing arresting rocket recovery technologies mainly include the following two typical structures: Four-corner symmetrical hook recovery method: Multiple symmetrical hook structures are arranged around the circumference of the rocket body, and corresponding arresting cable frames are set on the ground. Capture and deceleration are achieved through the cooperation of hooks and arresting cables.

[0004] Net-based recovery method: The rocket is completely covered by a large-area flexible arresting net. During the capture process, the kinetic energy is absorbed by the deformation of the net and the buffer device to achieve deceleration and recovery.

[0005] The above recycling methods have the following shortcomings: For four-corner symmetrical hook-type recovery methods, the recovery process is highly dependent on the rocket's attitude stability and landing accuracy. When the rocket experiences roll deviation or lateral shift during recovery, some hooks may fail to engage effectively. Existing hook-up structures mostly adopt a single-point independent action form, lacking redundancy and coordination mechanisms between hook-up units. If critical hook-up points fail to function effectively, it may lead to overall capture failure, resulting in a low recovery success rate, insufficient system robustness, and poor structural adaptability.

[0006] For net-based recovery methods, the barrier net structure is large and the system is complex. During the capture process, the force distribution is uneven, which can easily lead to localized force concentration problems. In addition, this method requires net repositioning after recovery, which is complicated and has high maintenance costs.

[0007] In addition, there are existing recovery structures based on a single arresting cable, which use hooks arranged in a ring around the rocket body to engage with the arresting cable for capture. While this type of structure has some redundancy in the circumferential direction, its redundancy design is mainly concentrated in the circumferential dimension. It lacks effective redundancy and compensation mechanisms in the longitudinal direction of the rocket, making it difficult to cope with attitude and trajectory uncertainties caused by pitch deviations, yaw disturbances, and descent speed fluctuations during recovery, thus affecting the overall capture stability and success rate.

[0008] Therefore, there is an urgent need to propose a rocket recovery auxiliary device with higher recovery robustness. By introducing a redundant capture mechanism in the longitudinal direction of the rocket, it can still achieve effective docking under non-ideal conditions such as pitch deviation and descent speed fluctuation, thereby improving the overall recovery success rate.

[0009] Meanwhile, existing rocket arresting and recovery technologies mostly rely on real rockets or high-cost test systems for verification, which has problems such as high test costs, high risks, and long cycles. There is an urgent need to build a low-cost rocket simulation verification system to build an experimental system for verifying the principle of reusable rocket landing and recovery, so as to reduce the research cost of arresting and recovery methods, shorten the experimental iteration cycle, and improve R&D efficiency. Summary of the Invention

[0010] To address the problems of low reliability and stability, complex recovery structure and process, and high dependence on control precision in arresting cable recovery, this invention provides a simple and easy-to-implement arresting cable recovery device, and simultaneously constructs a low-cost, high-efficiency rocket recovery control algorithm experimental system.

[0011] To achieve the above objectives, the present invention aims to provide a rocket recovery device based on a vertical multi-hook layout and its hydrodynamic rocket simulation and verification system, specifically as follows: A rocket recovery device based on a vertical multi-hook layout comprises a rocket body, a hooking mechanism, an actuation mechanism, and a recovery device body. The rocket body, hook limiter, and propulsion system constitute the rocket body. The hooking mechanism comprises the hook body, hook latch, and inductive proximity sensor. The actuation mechanism comprises an electric cylinder, torsion spring, and comb rod. The recovery device body comprises a support structure, arresting cable, guiding mechanism, and buffer mechanism.

[0012] The rocket body has a receiving groove structure on its outer side, and the hook body is vertically arranged within the receiving groove structure along the rocket's axis. The inner side of the hook body has a slot structure for accommodating and engaging the arresting cable, allowing the arresting cable to slide relative to the rocket surface and enter the slot of the hook body when the rocket approaches, thus achieving stable engagement. The propulsion system is located on the rocket body and adjusts the rocket's flight attitude and approach speed during recovery by controlling the nozzle's oscillation and thrust, enabling the rocket to approach the arresting cable at a predetermined angle and a relatively small velocity. A hook limiter is located on the deployment trajectory of the hook body to limit the hook body's ejection angle and ejection stroke, ensuring that the hook body remains in the predetermined capture posture after ejection, preventing excessive ejection that could cause structural interference or impact.

[0013] In the hook-and-hook mechanism, multiple hook bodies are arranged vertically along the rocket's axial direction to improve the rocket's capture tolerance when it contacts the arresting cable. Even with certain height, attitude, or contact position errors between the rocket and the arresting cable, at least one hook body can effectively engage with the arresting cable, thereby increasing the capture success rate. A hook latch is used to lock the hook body during flight, keeping it in a retracted state to prevent premature deployment due to flight vibrations, aerodynamic loads, or accidental triggering. An inductive proximity sensor is located near the hook body or inside its slot to detect whether the arresting cable has been effectively engaged and transmits the detection signal to the rocket control system to trigger the propulsion system to decelerate and shut down.

[0014] In the aforementioned actuation mechanism, the comb-shaped rod is used to lock multiple hook bodies simultaneously and cooperates with the hook latches to keep the hook bodies in a non-explosive state during flight. An electric cylinder connected to the comb-shaped rod is used to drive the comb-shaped rod to move after the recovery procedure is initiated, causing the comb-shaped rod to disengage from the hook latches and thus releasing the lock on the hook bodies. A torsion spring is located at the rotational connection between the hook body and the rocket body. It is in an energy-storing state when the hook body is in the retracted state; when the comb-shaped rod is unlocked, the torsion spring releases its stored energy, driving the hook body to quickly pop out from the retracted state to the working state.

[0015] In the main body of the recovery device, support structures are spaced apart, and a guide mechanism is fixed to the upper part of the support structure. The arresting cable is connected between the support structures through the guide mechanism. A buffer mechanism is located at the end or both sides of the arresting cable to apply preload to the cable. After the rocket engages with the arresting cable, the buffer mechanism absorbs the remaining kinetic energy of the rocket by releasing the cable length, damping, or elastic deformation, thereby reducing the impact load and gradually decelerating the rocket to a stable suspended state. The support structures can be installed on a ground platform or a water platform, making the device suitable for different recovery scenarios.

[0016] The aforementioned hydrodynamic rocket simulation and verification system is not merely a single physical support platform, but rather a comprehensive experimental system used to verify the landing and recovery principles of reusable rockets. It comprises the rocket body, the recovery unit, and, in conjunction with these components, an external water supply system, a launch support and guidance system, and an external monitoring and control system. The external water supply system, connected to the propulsion system via an inlet pipe, provides high-pressure water to the rocket body, enabling it to generate lift and attitude control under conditions not directly from a real rocket engine. The external launch support and guidance system supports, positions, and guides the rocket body during the initial experimental phase. The recovery unit is used for arresting, decelerating, and recovering the rocket body after its planned flight. The external monitoring and control system collects data on the rocket body's motion, attachment status, and recovery process parameters, and controls the propulsion system and recovery process. These components work together to form the experimental system for verifying the landing and recovery process of reusable rockets.

[0017] Compared with the prior art, the beneficial effects of the present invention are: High recovery robustness: The vertically arranged multiple hooks ensure that at least one hook can successfully catch the arresting cable even when the rocket's attitude fluctuates or the landing point deviates, avoiding the problem of overall capture failure due to a single hook not engaging, as is common in traditional circumferential layouts.

[0018] The locking and triggering mechanism boasts high reliability: The mechanical engagement of the hook latch and comb rod, along with the active pull unlocking by the electric cylinder, constitutes a repeatedly testable mechanical locking and triggering system, reducing the uncertainties associated with pyrotechnic devices or complex electronic locks. The hook limiter precisely controls the hook's ejection position.

[0019] Status-aware: Inductive proximity sensors can provide real-time feedback on the engagement status between the hook and the arresting cable, providing crucial closed-loop information for the control system and facilitating precise control of subsequent actions.

[0020] It does not affect the aerodynamic shape of the rocket during flight: The hook body is normally stored inside the rocket body and only pops out before recovery. It does not affect the aerodynamic shape of the rocket during the flight mission and improves flight stability.

[0021] Reducing testing costs and improving testing efficiency: The hydrodynamic rocket simulation and verification system constructs a complete experimental environment for the reusable rocket landing and recovery process. Using water as the propellant, it simulates flight and recovery, eliminating the need for expensive fuels, complex engine systems, and high-precision control systems, thus significantly reducing testing costs. The system has low requirements for site and environment; its core components can be manufactured using low-cost materials; it has a simple structure, is easy to process and assemble; and it supports multiple repeated tests and rapid reset, effectively reducing equipment wear and one-time testing expenses. It can serve as a low-cost, rapid experimental environment for the early verification of traditional rocket recovery technologies. Attached Figure Description

[0022] Figure 1 This is a schematic diagram of the overall structure of the rocket recovery device with a vertical multi-hook layout according to the present invention.

[0023] Figure 2 This is a partially enlarged schematic diagram of the rocket recovery device with a vertical multi-hook layout according to the present invention.

[0024] Figure 3 This is a schematic diagram of the hooking mechanism and actuation mechanism of the rocket recovery device with a vertical multi-hook layout according to the present invention in the released state.

[0025] Figure 4 This is a schematic diagram of the hooking mechanism and actuation mechanism of the rocket recovery device with a vertical multi-hook layout according to the present invention in the storage state.

[0026] Figure 5 This is a schematic diagram of the power system of the rocket recovery device with a vertical multi-hook layout according to the present invention.

[0027] The labels in the diagram are explained as follows: 1-Rocket body, 101-Rocket body, 102-Hook limiter, 103-Propulsion system, 1031-Water inlet pipe, 1032-Power nozzle, 1033-Roll bearing, 1034-Nozzle rotating bearing, 2-Hook mechanism, 201 - Hook body, 2011 - First hook, 2012 - Second hook, 2013 - Third hook 202-Hook clip, 2021-First hook clip, 2022-Second hook clip, 2023-Third hook clip, 203-Inductive proximity sensor, 2031-First inductive proximity sensor 2032 - Second inductive proximity sensor, 2033 - Third inductive proximity sensor, 3 - Action mechanism 301 - Electric cylinder, 3011 - First electric cylinder, 3012 - Second electric cylinder, 302 - Torsion spring, 3021 - First torsion spring 3022-Second torsion spring, 303-Comb rod, 4-Main body of recovery device, 401-Support structure, 402-Barrier cable, 403-Guide mechanism, 404-Buffer mechanism. Detailed Implementation

[0028] The following will refer to the accompanying drawings in the embodiments of the present invention. Figures 1-5 The technical solutions in the embodiments of the present invention are clearly and completely described herein. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0029] A rocket recovery device based on a vertical multi-hook layout includes a rocket body 1, a hooking mechanism 2, an actuation mechanism 3, and a recovery device body 4. The rocket body 1 includes a rocket body 101, a hook limiter 102, and a propulsion system 103. The hooking mechanism 2 includes a hook body 201, a hook latch 202, and an inductive proximity sensor 203. The actuation mechanism 3 includes an electric cylinder 301, a torsion spring 302, and a comb-shaped rod 303. The recovery device body 4 consists of a support structure 401, an arresting cable 402, a guiding mechanism 403, and a buffer mechanism 404.

[0030] The rocket body 1 is provided with a storage groove structure on the outside. The hook body 201 is arranged vertically along the rocket axis in the storage groove structure. The hook body 201 is provided with a slot structure for accommodating and engaging the arresting cable 402 on the inside, so that the rocket can achieve stable capture through the hook slot structure when it approaches the arresting cable 402.

[0031] The propulsion system 103 includes a water inlet pipe 1031, a power nozzle 1032, a rolling bearing 1033, and a nozzle rotation bearing 1034. The water inlet pipe 1031 is located at the bottom of the rocket body 101 and is used to introduce high-pressure water from an external water supply device into the power nozzle 1032. The power nozzle 1032 is located at the lower part of the rocket body 101 and is connected to the water inlet pipe 1031, used to eject high-pressure water to generate reaction thrust. The rolling bearing 1033 is located at the end of the water inlet pipe 1031 and is used to allow the rocket body 101 to rotate around the rocket's rolling axis. The nozzle rotation bearing 1034 is located at the mounting connection point of the power nozzle 1032 and is used to allow the power nozzle 1032 to swing around a pivot located at its bottom, parallel to the rocket's pitch or yaw axis, thereby adjusting the ejection direction of the power nozzle 1032. The hook body 201 includes a first hook 2011, a second hook 2012, and a third hook 2013 arranged sequentially along the rocket's axial direction. All three hooks are rotatably connected to a receiving groove structure on the outside of the rocket body 101, and are arranged vertically at intervals along the rocket's axial direction. The first hook 2011, second hook 2012, and third hook 2013 are all designed in a hook shape to accommodate the arresting cable 402, allowing the arresting cable 402 to slide along the surface of the rocket body 101 and enter the corresponding hook after contacting the rocket, preventing it from easily falling off.

[0032] The hook latch 202 includes a first hook latch 2021, a second hook latch 2022, and a third hook latch 2023 respectively corresponding to the first hook 2011, the second hook 2012, and the third hook 2013. Each hook latch is located at the locking position of the corresponding hook and is used to restrict the rotation of the corresponding hook in the stored state. The inductive proximity sensor 203 includes a first inductive proximity sensor 2031, a second inductive proximity sensor 2032, and a third inductive proximity sensor 2033, which are respectively located near the first hook 2011, the second hook 2012, and the third hook 2013 or inside their slots, and are used to detect the engagement status between the corresponding hook and the arresting cable 402.

[0033] The comb-shaped rod 303 is used to lock the multiple hook bodies 201 in a unified manner. It cooperates with the hook latch 202 to keep the hook bodies 201 in a non-expanding state during flight, thereby preventing premature deployment due to flight vibration, aerodynamic loads, or accidental triggering. The electric cylinder 301 is used to retract the comb-shaped rod 303, disengaging it from the constraint of the hook latch 202, thus unlocking the hooks.

[0034] The electric cylinder 301 includes a first electric cylinder 3011 and a second electric cylinder 3012. The first electric cylinder 3011 and the second electric cylinder 3012 are respectively connected to both sides or both ends of the comb rod 303, and are used to synchronously or collaboratively drive the comb rod 303 to move in a predetermined direction, so as to improve the stability of the comb rod 303 during the unlocking process.

[0035] The torsion spring 302 includes a first torsion spring 3021 and a second torsion spring 3022. The first torsion spring 3021 and the second torsion spring 3022 are respectively disposed at the rotational connection between the hook body 201 and the arrow body 101. They are used to store elastic potential energy when the hook body 201 is in the retracted state, and to release the stored energy after unlocking to drive the corresponding hook body 201 to pop outward.

[0036] The torsion spring 302 is disposed on the connecting shaft between the hook body 201 and the arrow body 101. After the comb rod 303 is unlocked, the torsion spring 302 releases its stored energy to drive the hook body 201 to quickly pop out from the retracted state and enter the working state. The hook limiter 102 is used to limit the pop-out angle and pop-out stroke of the hook body 201, so that the hook body 201 remains in the predetermined capture posture after popping out and avoids excessive popping that may cause interference or impact.

[0037] The inductive proximity sensor 203 is used to detect the engagement status between the hook body 201 and the arresting cable 402, and provides the detection signal to the rocket control system or ground control system to trigger the subsequent deceleration, shutdown, buffer release or recovery process switching of the power system 103, thereby improving the controllability and safety of the recovery process.

[0038] In the main body 4 of the recovery device, the support structure 401 in this embodiment is a tower, and two towers are set on the ground at intervals. The guide mechanism 403 in this embodiment is a pulley, which is fixedly set at the ends of the two support structures 401. The arresting cable 402 connects the two support structures through the guide mechanism 403, and the portions of the arresting cable 402 on both sides of the guide mechanism 403 are respectively connected to the buffer mechanism 404. The buffer mechanism 404 includes a winch and a buffer, which are used to apply a preload to the arresting cable 402 and to buffer the force applied to the rocket by cooperating with the extension and retraction of the arresting cable 402 after the rocket contacts the arresting cable 402.

[0039] In this embodiment, the hydrodynamic rocket simulation verification system comprises a rocket body 1, a recovery device body 4, and an external water supply device, a launch support and guidance device, and an external monitoring and control device used in conjunction with them. The external water supply device is connected to the propulsion system 103 via a water inlet pipe 1031, supplying high-pressure water to the rocket body 1, enabling the propulsion system 103 to generate water jet reaction thrust, thereby providing the rocket body 1 with the lift and attitude adjustment power required for simulated flight. The launch support and guidance device is located at the takeoff position of the rocket body 1, used to support, position, and guide the rocket body 1 before the test begins, maintaining the rocket body 1 in a predetermined initial attitude. The recovery device body 4 is located at the end of the predetermined recovery path of the rocket body 1, used to intercept, capture, buffer, decelerate, and recover the rocket body 1 after it completes its predetermined flight. The external monitoring and control device works in conjunction with the rocket body 1 and the recovery device body 4, used to collect the motion state, attachment state, and recovery process parameters of the rocket body 1, and to monitor and control the propulsion system 103 and the recovery process based on the collected results. Thus, the rocket body 1, the recovery device body 4, the external water supply device, the launch support and guidance device, and the external monitoring and control device work together to form a simulation verification system for verifying the landing and recovery principle of reusable rockets.

[0040] The overall working process of this device is as follows: Step 1: Flight Preparation Phase. The rocket body 1 is placed on the launch platform, and the power system 103 is in standby mode. The support structure 401 of the recovery device body, the arresting cable 402, the guide mechanism 403, and the buffer mechanism 404 are installed in place. The arresting cable 402 is in a pre-tensioned state, and the buffer mechanism 404 is pre-tensioned. At this time, in the retractable hook mechanism, the comb rod 303 is extended under the control of the electric cylinder 301 and engages with the hook buckle 202, locking the hook body 201 in the storage slot inside the rocket body 1. The torsion spring 302 is in a compressed and energy-storing state.

[0041] Step Two: Recovery Preparation Phase. After the main body of rocket 1 completes its mission, the propulsion system 103 adjusts the rocket's descent speed and attitude, causing it to fly towards the recovery device area at a predetermined angle and speed. When the rocket enters the predetermined distance range (approximately 2 meters) before approaching the recovery device, the control system detects the location of the recovery device and triggers the recovery procedure.

[0042] Step 3: During the hook ejection stage, the control system sends a signal to the electric cylinder 301, which actuates, quickly pulling back the comb rod 303. The comb rod 303 disengages from the hook latch 202, releasing the lock on the hook body 201. Driven by the torsion spring 302, the hook body 201 quickly ejects from the storage slot until it is stopped by the hook limiter 102, entering the ready-to-hook working state. The inductive proximity sensor 203 starts working at this time, monitoring the hook status in real time.

[0043] Step Four: Approach and Contact Phase. The rocket continues its flight towards the recovery device along a predetermined trajectory. The rocket's vertically arranged multi-hook layout ensures that it can contact the arresting cable 402 within a certain positional deviation range as it approaches the recovery device. The rocket approaches the recovery device with a predetermined forward-leaning attitude, and its front end contacts the arresting cable 402 first.

[0044] Step 5: Capture and Buffering Phase During the rocket's approach to the arresting cable 402, the rocket decelerates by adjusting its thrust output through the propulsion system 103, allowing it to approach the arresting cable 402 at a relatively low relative speed. When the rocket enters the predetermined distance range, the control system adjusts the output of the propulsion system 103 until it approaches a near-stationary state. Under low relative speed conditions, the rocket contacts the arresting cable 402, causing the cable to slide relative to the rocket surface and engage with the hook body 201, thus achieving engagement. Since the hook body 201 contains three hooks: a first hook 2011, a second hook 2012, and a third hook 2013, arranged vertically along the rocket's axis, even with positional deviations, at least one hook can still effectively engage with the arresting cable 402, improving the capture success rate. After the connection is completed, the inductive proximity sensor 203 detects the presence of the arresting cable 402 and sends a signal to the control system. The control system further reduces the output of the power system 103 until it is close to a shutdown state. The buffer mechanism 404 starts to work, absorbing the remaining kinetic energy of the rocket by releasing the length of the arresting cable 402 or providing damping, so as to further decelerate the rocket until it reaches a stable suspended state, thereby reducing the impact load and protecting the rocket structure and the arresting cable 402 from damage.

[0045] Step Six: Upon completion of the recovery phase, the ground control system remotely and slowly releases the arresting cable 402 in the buffer mechanism 404, gently lowering the rocket to the ground. After the rocket has come to a complete stop, ground personnel can manually or remotely extend the comb-shaped rod 303 again via the electric cylinder 301, pushing the hook body 201 back into the storage slot and locking it. The rocket is then removed from the arresting cable 402 for subsequent inspection, maintenance, or preparation for relaunch.

[0046] The above description is merely an embodiment of the present invention and is not intended to limit the scope of protection of the present invention. Any equivalent structural transformations made based on the description and drawings of the present invention, or direct or indirect applications in other related technical fields, are included within the scope of protection of the present invention.

Claims

1. A rocket recovery device based on a vertical multi-hook layout, characterized in that: The rocket body, hook mechanism, actuation mechanism, and recovery device body are composed of the rocket body, hook limiter, and power system; the hook mechanism consists of the hook body, hook buckle, and inductive proximity sensor; the actuation mechanism consists of electric cylinder, torsion spring, and comb rod; and the recovery device body consists of support structure, arresting cable, guide mechanism, and buffer mechanism.

2. The rocket recovery device based on a vertical multi-hook layout according to claim 1, characterized in that: The rocket body has a storage groove structure on the outer side, and the hook body is arranged vertically along the rocket axis in the storage groove structure; the hook body has a slot structure on the inner side for accommodating and engaging the arresting cable, so that when the rocket approaches the arresting cable, the arresting cable can slide relative to the rocket surface and enter the slot of the hook body to achieve stable engagement.

3. A rocket recovery device based on a vertical multi-hook layout according to claim 1, characterized in that: The propulsion system is mounted on the rocket body. By controlling the oscillation of the nozzle and the magnitude of the thrust, the rocket's flight attitude and approach speed during the recovery process are adjusted, allowing the rocket to approach the arresting cable at a predetermined angle and a relatively small relative speed.

4. A rocket recovery device based on a vertical multi-hook layout according to claim 1, characterized in that: The hook limiter is set on the unfolding trajectory of the hook body to limit the pop-out angle and pop-out stroke of the hook body, so that the hook body remains in the predetermined capture posture after popping out, avoiding excessive popping that could cause structural interference or impact.

5. A rocket recovery device based on a vertical multi-hook layout according to claim 1, characterized in that: In the hooking mechanism, multiple hook bodies are arranged vertically along the rocket body axis to improve the capture tolerance capability when the rocket contacts the arresting cable; ensure that at least one hook body can form an effective engagement with the arresting cable; the hook buckle is used to lock the hook body during the flight phase to keep the hook body in a retracted state; an inductive proximity sensor is set near the hook body or inside its slot to detect whether the arresting cable has completed an effective engagement and transmits the detection signal to the rocket control system to trigger the propulsion system to decelerate and stop.

6. A rocket recovery device based on a vertical multi-hook layout according to claim 1, characterized in that: In the aforementioned action mechanism, the comb rod is used to lock multiple hook bodies in a unified manner and cooperates with the hook buckle to keep the hook body in a non-exploding state during the flight phase; the electric cylinder is connected to the comb rod and is used to drive the comb rod to move after the recovery program is started, so that the comb rod is released from the constraint of the hook buckle, thereby releasing the lock on the hook body; the torsion spring is set at the rotational connection between the hook body and the arrow body, and is in an energy storage state when the hook body is in the retracted state; when the comb rod is unlocked, the torsion spring releases the stored energy, driving the hook body to quickly pop out from the retracted state to the working state.

7. A rocket recovery device based on a vertical multi-hook layout according to claim 1, characterized in that: In the main body of the recovery device, support structures are spaced apart, a guide mechanism is fixed to the upper part of the support structure, and the arresting cable is connected between the support structures through the guide mechanism; a buffer mechanism is set at the end or both sides of the arresting cable to apply pre-tension to the arresting cable, and after the rocket is attached to the arresting cable, it absorbs the remaining kinetic energy of the rocket by releasing the cable length, damping buffer, or elastic deformation, thereby reducing the captured impact load and gradually decelerating the rocket to a stable suspended state.

8. A rocket recovery device based on a vertical multi-hook layout according to claim 1 or 7, characterized in that: The support structure is set on a ground platform or a water surface platform, and is suitable for different recycling scenarios.

9. A hydrodynamic rocket simulation and verification system, characterized in that: The overall verification system consists of the rocket body, the recovery unit, and the external water supply system, launch support and guidance system, and external monitoring and control system used in conjunction with them. The external water supply system, connected to the propulsion system via an inlet pipe, provides high-pressure water to the rocket body, enabling it to generate lift and attitude control under non-real rocket engine propulsion conditions. The external launch support and guidance system supports, positions, and guides the rocket body during the initial test phase. The recovery unit is used for arresting, capturing, decelerating, and recovering the rocket body after it completes its planned flight. The external monitoring and control system collects data on the rocket body's motion, attachment status, and recovery process parameters, and controls the propulsion system and recovery process.

10. A method for operating a rocket recovery device based on a vertical multi-hook layout, characterized in that: Step 1: Flight preparation phase. The rocket body is placed on the launch platform and the power system is in standby mode. The support structure, arresting cable, guide mechanism and buffer mechanism of the recovery device body are installed in place. The arresting cable is in a pre-tightened state and the buffer mechanism is pre-tightened. At this time, in the retractable hook mechanism, the comb rod is extended under the control of the electric cylinder and engages with the hook buckle, locking the hook body in the storage slot inside the rocket body. The torsion spring is in a compressed energy storage state. Step Two: Recovery Preparation Phase After the main body of the rocket completes its mission, the propulsion system adjusts the rocket's descent speed and attitude to fly towards the recovery device area at a predetermined angle and speed; when the rocket enters the predetermined distance range before approaching the recovery device, the control system detects the location of the recovery device and triggers the recovery procedure. Step 3: During the hook ejection stage, the control system sends a signal to the electric cylinder, which then actuates and quickly pulls the comb rod back. The comb rod disengages from the hook latch, releasing the lock on the hook body. Driven by the torsion spring, the hook body quickly ejects from the storage slot until it is stopped by the hook limiter, entering the ready-to-hook working state. At this time, the inductive proximity sensor starts working to monitor the hook status in real time. Step 4: Approach and Contact Phase The rocket continues to fly toward the recovery device along the predetermined trajectory. The rocket's vertically arranged multi-hook layout ensures that the rocket contacts the arresting cable as it approaches the recovery device. The rocket approaches the recovery device with a predetermined forward tilt attitude, and the front end contacts the arresting cable first. Step 5: Capture and Buffering Phase. During the rocket's approach to the arresting cable, the rocket decelerates by adjusting its thrust output through the propulsion system, allowing it to approach the arresting cable at a relatively low relative speed. When the rocket enters the predetermined distance range, the control system adjusts the propulsion output until it approaches a near-stationary state. Under low relative speed conditions, the rocket contacts the arresting cable, which slides relative to the rocket surface and engages with the hook body. The hook body includes a first hook, a second hook, and a third hook, arranged vertically along the rocket's axis to ensure that at least one hook can engage with the arresting cable. After engagement, the inductive proximity sensor detects the arresting cable and sends a signal to the control system. The control system further reduces the propulsion output until it approaches a near-stop state. The buffer mechanism then activates, releasing the length of the arresting cable or providing damping to absorb the rocket's remaining kinetic energy, further decelerating the rocket until it reaches a stable suspended state, reducing impact loads and protecting the rocket structure and arresting cable from damage. Step Six: Recovery Completed Stage. The ground control system remotely releases the arresting cable in the buffer mechanism, slowly lowering the rocket to the ground. After the rocket comes to a complete stop, ground personnel manually or remotely extend the comb rod of the electric cylinder again, push the hook body into the recovery slot and lock it, and then remove the rocket from the arresting cable for subsequent testing, maintenance or preparation for relaunch.

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