A tower crane arm control method, device and equipment for rocket recovery

Abstract

The present application relates to the technical field of rocket recovery, and discloses a tower mechanical arm control method, device and equipment for rocket recovery, the method comprising: acquiring state parameters of a rocket to be recovered, including the height of a recovery hook from a mechanical arm; controlling the mechanical arm to dynamically center the rocket to be recovered when the recovery hook is at a first height from the mechanical arm, so that the rocket to be recovered is located on the center line of the mechanical arm when the recovery hook is at a second height from the mechanical arm; controlling the mechanical arm to dynamically close the arms when the recovery hook is at the second height from the mechanical arm, so that the closing of the arms is completed when the recovery hook is at a third height from the mechanical arm; and keeping the mechanical arm unchanged when the recovery hook is at the third height from the mechanical arm, until the rocket to be recovered falls to the mechanical arm. The present application associates the action of capturing the rocket by the mechanical arm with the real-time state of the rocket, avoids the collision between the mechanical arm and the rocket during the recovery process, improves the safety of the rocket recovery, and divides the rocket recovery process into three stages, namely centering, closing of the arms and keeping, to complete reliable rocket recovery.

Description

Technical Field

[0001] This invention relates to the field of rocket recovery technology, and specifically to a control method, device, and equipment for a rocket recovery tower robotic arm. Background Technology

[0002] In the aerospace field, the core value of rocket recovery lies in overcoming the limitation of traditional single-use rockets that are scrapped after launch. By reusing key components of the rocket body through recovery, the hardware cost of a single space launch can be significantly reduced, providing economic support for the large-scale advancement of space missions.

[0003] Currently, the mainstream rocket recovery technologies are vertical recovery via landing legs and capture and recovery via a robotic arm. Capture and recovery via a robotic arm eliminates the need for landing legs on the rocket body, effectively reducing its dry weight and further increasing its payload capacity. During rocket recovery, the control of the robotic arm directly determines the success or failure of the mission. Therefore, how to control the robotic arm for rocket recovery is a problem that needs to be solved. Summary of the Invention

[0004] This invention provides a method, apparatus, and equipment for controlling a tower robotic arm for rocket recovery, in order to solve the problem of controlling a tower robotic arm for rocket recovery.

[0005] In a first aspect, the present invention provides a method for controlling a robotic arm on a rocket recovery tower, the method comprising:

[0006] The status parameters of the rocket to be recovered are acquired in real time, including the height of the recovery hook from the robotic arm.

[0007] When the recovery hook is at the first height of the robotic arm, the control of the robotic arm is triggered, and the robotic arm is dynamically centered to be recovered, so that when the recovery hook is at the second height of the robotic arm, the rocket to be recovered is located on the center line of the robotic arm.

[0008] When the retrieval hook is at the second height from the robotic arm, control the robotic arm to dynamically close, so that the robotic arm completes the closing when the retrieval hook is at the third height from the robotic arm.

[0009] When the recovery hook is at the third height from the robotic arm, the state of the robotic arm remains unchanged until the rocket to be recovered falls onto the robotic arm.

[0010] This invention acquires the real-time status parameters of the rocket to be recovered, ensuring that the robotic arm control can dynamically adjust according to the actual descent of the rocket. It also correlates the robotic arm's actions during rocket capture with the rocket's real-time status, adapting to different return trajectories and preventing collisions between the robotic arm and the rocket during recovery, thus improving the safety of rocket recovery. When the recovery hook reaches the first altitude, the robotic arm is dynamically aligned so that the rocket is on the robotic arm's centerline when the hook reaches the second altitude, reducing the difficulty of closing the arm. When the hook reaches the second altitude, the robotic arm dynamically closes, completing the closure when the hook reaches the third altitude, effectively ensuring that the rocket lands on the robotic arm during its vertical descent. When the hook reaches the third altitude, the robotic arm maintains its position until the rocket lands on it, completing a reliable rocket recovery.

[0011] In a second aspect, the present invention provides a control device for a rocket recovery tower robotic arm, the device comprising:

[0012] The first acquisition module is used to acquire the status parameters of the rocket to be recovered in real time, including the height of the recovery hook of the rocket from the robotic arm.

[0013] The first control module is used to trigger the control of the robotic arm when the recovery hook of the rocket to be recovered is at a first height from the robotic arm, and to control the robotic arm to dynamically center the rocket to be recovered so that when the recovery hook is at a second height from the robotic arm, the rocket to be recovered is located on the center line of the robotic arm.

[0014] The second control module is used to control the robotic arm to dynamically close when the retrieval hook is at a second height from the robotic arm, so that the robotic arm completes the closing when the retrieval hook is at a third height from the robotic arm.

[0015] The third control module is used to keep the state of the robotic arm unchanged when the recovery hook is at a third height from the robotic arm, until the rocket to be recovered falls onto the robotic arm.

[0016] Thirdly, the present invention provides an electronic device, comprising: a memory and a processor, the memory and the processor being communicatively connected to each other, the memory storing computer instructions, and the processor executing the computer instructions to perform the control method for a rocket recovery tower robotic arm as described in the first aspect or any corresponding embodiment thereof.

[0017] Fourthly, the present invention provides a computer-readable storage medium storing computer instructions for causing a computer to execute the control method for a rocket recovery tower robotic arm according to the first aspect or any corresponding embodiment described above. Attached Figure Description

[0018] To more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0019] Figure 1 This is a flowchart of a control method for a rocket recovery tower robotic arm according to an embodiment of the present invention;

[0020] Figure 2 This is a schematic diagram of the three stages of rocket recovery according to an embodiment of the present invention;

[0021] Figure 3 This is a geometric schematic diagram of the launch tower and the rocket to be recovered according to an embodiment of the present invention;

[0022] Figure 4 This is a schematic diagram of the three stages of rocket recovery according to an embodiment of the present invention;

[0023] Figure 5 This is a flowchart of another control method for a rocket recovery tower robotic arm according to an embodiment of the present invention;

[0024] Figure 6 This is a structural block diagram of a control device for a rocket recovery tower robotic arm according to an embodiment of the present invention;

[0025] Figure 7 This is a schematic diagram of the hardware structure of an electronic device according to an embodiment of the present invention. Detailed Implementation

[0026] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0027] It is understood that before using the technical solutions disclosed in the various embodiments of the present invention, users should be informed of the types, scope of use, and usage scenarios of the personal information involved in the present invention and their authorization should be obtained in accordance with relevant laws and regulations through appropriate means.

[0028] The terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this invention, "a plurality of" means two or more, unless otherwise explicitly specified.

[0029] The mainstream rocket recovery technologies are vertical recovery via landing legs and capture and recovery via a robotic arm. Capture and recovery via a robotic arm eliminates the need for landing legs on the rocket body, effectively reducing dry weight and increasing payload capacity. During rocket recovery, the control of the robotic arm directly determines the success or failure of the mission. Therefore, how to control the robotic arm for rocket recovery is a problem that needs to be solved. This invention obtains the real-time state parameters of the rocket to be recovered, ensuring that the robotic arm control can dynamically adjust according to the actual descent state of the rocket. It also correlates the robotic arm's actions during rocket capture with the rocket's real-time state, adapting to different return trajectories and avoiding collisions between the robotic arm and the rocket during recovery, thus improving the safety of rocket recovery. When the recovery hook reaches the first height, the robotic arm is dynamically aligned so that when the hook reaches the second height, the rocket is positioned on the robotic arm's centerline, reducing the difficulty of closing the arm. When the hook reaches the second height, the robotic arm dynamically closes, completing the closure when the hook reaches the third height, effectively ensuring that the rocket ultimately lands on the robotic arm during vertical descent. When the recovery hook reaches the third altitude, the control robotic arm remains in position until the rocket falls onto the robotic arm, completing a reliable rocket recovery.

[0030] According to an embodiment of the present invention, a method for controlling a tower robotic arm for rocket recovery is provided. It should be noted that the steps shown in the flowchart in the accompanying drawings can be executed in a computer system such as a set of computer-executable instructions. Furthermore, although a logical order is shown in the flowchart, in some cases, the steps shown or described may be executed in a different order than that shown here.

[0031] This embodiment provides a control method for a rocket recovery tower robotic arm. Figure 1 This is a flowchart of a control method for a rocket recovery tower robotic arm according to an embodiment of the present invention, such as... Figure 1 As shown, the process includes the following steps:

[0032] Step S101: Real-time acquisition of the status parameters of the rocket to be recovered, including the height of the recovery hook of the rocket from the robotic arm.

[0033] Specifically, for the rocket to be recovered, its status parameters, including the real-time position and motion parameters of the rocket, are acquired in real time through sensors and other equipment. This provides accurate data support for the subsequent robotic arm recovery control and avoids capture deviations due to parameter lag or lack.

[0034] Step S102: When the recovery hook of the rocket to be recovered is at a first height from the robotic arm, the control of the robotic arm is triggered to dynamically center the rocket to be recovered, so that when the recovery hook is at a second height from the robotic arm, the rocket to be recovered is located on the center line of the robotic arm.

[0035] Specifically, based on the characteristics of the rocket's return to the launch tower's robotic arm capture area, the rocket recovery process is divided into three stages, achieving phased and progressive precise control. Figure 2 This is a schematic diagram of the three stages of rocket recovery according to an embodiment of the present invention, as shown below. Figure 2 As shown, the first stage is the external dynamic rocket centering stage, which begins when the recovery hook of the rocket to be recovered is at the first height from the robotic arm and ends when the recovery hook is at the second height from the robotic arm; the second stage is the internal dynamic arm-clamping stage, which begins when the recovery hook is at the second height from the robotic arm and ends when the recovery hook is at the third height from the robotic arm; the third stage is the rocket landing stage, which begins when the recovery hook is at the third height from the robotic arm and ends when the recovery hook lands on the robotic arm.

[0036] The core objective of the first stage is to eliminate the initial positional deviation between the rocket and the robotic arm. By controlling the overall rotation of the robotic arm, the rocket to be recovered is precisely positioned on the center line of the robotic arm at the end of this stage, which reduces the alignment difficulty for the subsequent arm-joining stage and avoids collisions caused by initial deviations.

[0037] Step S103: When the retrieval hook is at the second height from the robotic arm, control the robotic arm to dynamically close, so that the robotic arm completes the closing when the retrieval hook is at the third height from the robotic arm.

[0038] Specifically, for the second stage, the core objective is to achieve a smooth transition of the robotic arm from the centering state to the closed clamping state, avoiding collisions with the rocket body or incomplete closing due to improper closing speed. This ensures that by the end of this stage, the left and right robotic arms have closed and stably clamped the rocket, providing structural protection for the safe load-bearing of the subsequent arm-dropping stage.

[0039] Step S104: When the recovery hook is at the third height from the robotic arm, the state of the robotic arm is kept unchanged until the rocket to be recovered falls onto the robotic arm.

[0040] Specifically, in the third stage, the robotic arm has completed its closing action and is in a clamping, load-bearing state. No additional motion control is required; its structural shape alone forms a physical constraint on the rocket to be recovered, limiting its horizontal deviation and allowing it to fall only vertically. This guides the rocket to fall vertically under its own gravity until the recovery hook is fully on the upper surface of the robotic arm, completing rocket recovery. This lack of control in this stage reduces redundant losses in the robotic arm's drive system and ensures a safe and controllable descent process through a stable constraint structure. It prevents rocket attitude instability caused by additional robotic arm movements, ultimately achieving precise rocket recovery.

[0041] This invention acquires the real-time status parameters of the rocket to be recovered, ensuring that the robotic arm control can dynamically adjust according to the actual descent of the rocket. It also correlates the robotic arm's actions during rocket capture with the rocket's real-time status, adapting to different return trajectories and preventing collisions between the robotic arm and the rocket during recovery, thus improving the safety of rocket recovery. When the recovery hook reaches the first altitude, the robotic arm is dynamically aligned so that the rocket is on the robotic arm's centerline when the hook reaches the second altitude, reducing the difficulty of closing the arm. When the hook reaches the second altitude, the robotic arm dynamically closes, completing the closure when the hook reaches the third altitude, effectively ensuring that the rocket lands on the robotic arm during its vertical descent. When the hook reaches the third altitude, the robotic arm maintains its position until the rocket lands on it, completing a reliable rocket recovery.

[0042] This embodiment provides a control method for a rocket recovery tower robotic arm, which specifically includes the following steps:

[0043] Step S201: Acquire the real-time status parameters of the rocket to be recovered, including the height of the recovery hook from the robotic arm. For details, please refer to [link to relevant documentation]. Figure 1 Step S101 of the illustrated embodiment will not be described again here.

[0044] Step S202: Take the rotation center of the robotic arm as the origin.

[0045] Specifically, before controlling the robotic arm, a tower coordinate system is established through steps S202-S206, with the rotation center of the robotic arm set as the origin of the coordinate system. This center is the core reference point for the overall rotation of the robotic arm and the opening and closing movements of the left and right arms. Using the rotation center as the origin ensures that there is no reference deviation in subsequent robotic arm motion control and the calculation of the relative position between the rocket and the robotic arm.

[0046] Step S203: Take the length direction of the robotic arm when it is in the zero position of the arm closed as the X-axis.

[0047] Specifically, the zero-position of the robotic arms refers to the state when the left and right robotic arms are completely closed (angle of 0). At this time, the length direction of the robotic arms is the direction of the core force on the rocket and the reference direction of the action. Setting this direction as the X-axis allows X-axis-based calculations to directly reflect the relative positional relationship between the opening and closing states of the robotic arms and the rocket.

[0048] Step S204: The direction perpendicular to the X-axis and upward is taken as the Y-axis.

[0049] Specifically, the rocket's return process is mainly a vertical descent. The direction perpendicular to the X-axis and upward is set as the Y-axis, so that the height of the rocket recovery hook from the robotic arm directly corresponds to the Y-axis coordinate value, making it easy to intuitively judge the rocket's descent stage through the Y-axis parameters.

[0050] Step S205: Determine the Z-axis based on the X-axis and Y-axis using the right-hand rule.

[0051] Specifically, based on the defined X and Y axes, the Z axis is determined by the right-hand rule to describe the rocket's offset in the forward and backward direction (Z-axis).

[0052] Step S206: Establish the tower coordinate system based on the origin, X-axis, Y-axis and Z-axis.

[0053] Specifically, by establishing a tower coordinate system, a unified calculation dimension is provided for subsequent control, rather than relying on fuzzy relative position judgments. This ensures precise matching between the robotic arm's movements and the rocket's dynamics during rocket recovery, avoiding control deviations caused by inconsistent parameter dimensions.

[0054] Step S207: When the recovery hook is at a first height from the robotic arm, control of the robotic arm is triggered to dynamically center the rocket to be recovered, so that when the recovery hook is at a second height from the robotic arm, the rocket to be recovered is located on the center line of the robotic arm.

[0055] Specifically, step S207 includes:

[0056] Step a1: When the recovery hook is at the first height from the robotic arm, calculate the first total descent time and the angle parameter between the start and start times based on the state parameters of the rocket to be recovered at the start of control.

[0057] Specifically, when the retrieval hook is at the first height of the robotic arm, control of the robotic arm is initiated, and the current moment is the control initiation moment. The first total descent time is calculated using the following formula (1), which is the predicted time required for the retrieval hook to descend from the first height to the second height. This directly determines the time reference for the overall rotation of the robotic arm, ensuring that the robotic arm can accurately eliminate the centering deviation at the end of the first stage. Only by clearly defining the total duration of the first stage can the rotational angular velocity of the robotic arm be further planned, ensuring that the robotic arm can eliminate the centering deviation exactly at the end of the first stage, and avoiding misalignment due to a fuzzy time reference.

[0058] (1)

[0059] In the formula, Indicates the first total descent time; Indicates the first altitude; Indicates the second altitude; This indicates the velocity of the rocket body to be recovered along the Y-axis at the moment of launch.

[0060] Figure 3 This is a geometric schematic diagram of the launch tower and the rocket to be recovered according to an embodiment of the present invention, as shown below. Figure 3 As shown, the robotic arm includes a left robotic arm and a right robotic arm. The angle between the horizontal projection of the line connecting the center of the rocket to be recovered and the origin of the launch tower coordinate system and the X-axis. This indicates the angle between the centerline of the tower robotic arm and the X-axis. This indicates the angle of the robotic arm at the moment of activation; the robotic arm operates at the set angle. Overall rotation. At the start of control, the angle between the centerline and the X-axis is calculated to reflect the initial orientation of the robotic arm at the start of control, thus clarifying the current reference attitude of the robotic arm. In addition, the angle between the horizontal projection of the line connecting the arrow center and the origin and the X-axis is calculated to reflect the initial position of the rocket to be recovered at the start of control. Furthermore, the angle between the horizontal projection and the centerline is calculated to reflect the initial deviation of the rocket from the centerline of the robotic arm. The above three angles are calculated using the following formula (2) as the angle parameters at the start of control, which together constitute the deviation quantification benchmark for the first stage of centering control, providing direction for the subsequent dynamic adjustment of the overall rotation of the robotic arm, and ensuring that the centering process always revolves around eliminating deviation.

[0061] (2)

[0062] In the formula, Indicates the angle between the centerline at the moment of control activation and the X-axis; The angle between the horizontal projection at the moment of control activation and the X-axis; This indicates the coordinate of the center of the cross-section of the arrow body at the lower end of the recovery hook on the Z-axis at the moment of activation. This indicates the coordinate of the center of the cross-section of the arrow body at the lower end of the recovery hook on the X-axis at the moment of activation. The angle between the horizontal projection at the moment of control activation and the centerline.

[0063] Step a2: Calculate the angular velocity at the start of control based on the angle parameters between the first total descent time and the start of control.

[0064] Specifically, the angle between the horizontal projection and the centerline in the angle parameter at the start of control is taken as the deviation to be eliminated, and the first total descent time is taken as the total time for deviation elimination. The following formula (3) is used to determine the angular velocity at which the robotic arm needs to rotate as a whole so that the deviation can be eliminated just at the end of the first stage, so that the rocket is accurately positioned on the centerline of the robotic arm. This provides a speed target for the centering control in the first stage and avoids the robotic arm rotating too fast, which would cause overshoot, or too slow, which would cause residual deviation.

[0065] (3)

[0066] In the formula, This indicates the angular velocity at the moment of initiation of control.

[0067] Step a3: Determine the first transition time based on the first total descent time, and calculate the first transition angular velocity based on the angular velocity at the start of control.

[0068] Specifically, in the initial stage of the first phase of control activation, the robotic arm needs to switch from a stationary state to a rotating state. To avoid sudden changes in angular velocity causing impacts to the robotic arm's drive components, structural vibrations, or precision deviations, transition control is required to ensure a smooth transition of movements. This includes... The first transition time is determined to ensure the robotic arm has sufficient time to smoothly switch from a stationary position to the target angular velocity, achieving a balance between structural stability and alignment timeliness. Simultaneously, Determine the first transition angular velocity, which is the target velocity that the robotic arm needs to reach at the end of the transition phase.

[0069] Step a4: During the first transition time, the angular velocity of the robotic arm is controlled to transition to the first transition angular velocity using a parabolic transition algorithm.

[0070] Specifically, during the first transition time, a smooth transition of angular velocity is achieved through a parabolic transition algorithm. The real-time angular velocity corresponding to each moment during the transition phase can be calculated using the following formula (4). Taking the first transition time as the time base, with 0 as the starting point and the first transition angular velocity as the ending point, the real-time velocity is planned according to the parabolic law. That is, the angular velocity rises slowly in the early stage and gradually approaches the target velocity in the later stage, forming a continuous velocity curve without sudden changes. The robotic arm drive system will dynamically adjust according to this real-time angular velocity to ensure that the first transition angular velocity is reached at the end of the first transition time.

[0071] (4)

[0072] In the formula, This represents the parabolic transition algorithm; This indicates the first transition time.

[0073] In some optional implementations, when the robotic arm rotates in real time according to the above formula (4), the angle between its centerline and the X-axis will change with the change of angular velocity during the rotation. If only the angular velocity is adjusted and the synchronous calculation of the angle is ignored, it is easy to cause the actual posture of the robotic arm to deviate from the target posture, affecting the centering accuracy. Therefore, the angle value corresponding to the real-time angular velocity is determined by the following formula (5) to ensure that while the robotic arm adjusts the angular velocity according to the parabolic transition algorithm, its centerline posture is also updated accordingly. This avoids the asynchronous movement of angular velocity and angle, and can also provide real-time feedback on the current centering progress of the robotic arm through the angle parameter, providing a benchmark for subsequent dynamic correction of centering deviation.

[0074] (5)

[0075] Step a5: Based on the state parameters of the rocket to be recovered at the end of the first transition time, calculate the first remaining time, the included angle parameter, and the overall angular velocity corresponding to the end of the first transition time. The first remaining time represents the time it takes for the recovery hook to descend from the current altitude to the second altitude.

[0076] Specifically, at the end of the first transition time, the robotic arm needs to switch from the starting state of smooth angular velocity transition to the stable centering state of precise tracking of the rocket. For this purpose, it is necessary to obtain the core control parameters of the robotic arm at the end of the first transition time, and use these as a reference for subsequent centering actions. First, from the state parameters of the rocket to be recovered obtained at the end of the first transition time, the height of the recovery hook from the robotic arm and the velocity of the rocket body on the Y-axis are obtained and substituted into the above formula (1) to obtain the remaining time for the recovery hook to descend from the current height to the second height, that is, the first remaining time, which provides a time reference for subsequent adjustment of the robotic arm rotation rhythm. Then, the end of the first transition time is substituted into the above formula (5) to obtain the angle between the centerline and the X-axis at the end of the first transition time. Then, from the state parameters at the end of the first transition time, the coordinates of the center of the rocket body section of the lower end face of the recovery hook on the X-axis and Z-axis are obtained. Combined with the angle between the centerline and the X-axis at the end of the first transition time, they are substituted into the above formula (2) to obtain the angle between the horizontal projection and the X-axis and the angle between the horizontal projection and the centerline at the end of the first transition time. Finally, the angle between the first remaining time corresponding to the end of the first transition and the horizontal projection and the center line is substituted into the following formula (6) to obtain the overall angular velocity at the end of the first transition.

[0077] (6)

[0078] In the formula, This represents the overall angular velocity at time n; This represents the low-pass filter coefficient, with a value range of 0 to 1; Indicates the angular velocity at the moment of control activation; This represents the first remaining time at time n.

[0079] Step a6: Based on the first remaining time, included angle parameter, and overall angular velocity corresponding to the end of the first transition, as well as the state parameters of the rocket to be recovered at the next moment, calculate the first remaining time corresponding to the next moment.

[0080] Specifically, after entering the stable alignment phase in the first stage, refer to step a5 to calculate the first remaining time, calculate the first remaining time corresponding to the next moment after the end of the first transition, and ensure that the first remaining time always matches the actual descent progress of the rocket, providing a time basis for subsequent angular velocity planning.

[0081] Step a7: Based on the state parameters of the next moment and the first remaining time, predict the first intermediate angle parameter and the overall angular velocity of the robotic arm at the next moment, and control the angle parameter and angular velocity of the robotic arm to transition to the corresponding first intermediate angle parameter and overall angular velocity through the parabolic transition algorithm.

[0082] Specifically, in order to achieve precise matching of the dynamic position of the robotic arm and the rocket in the stable centering process, it is necessary to first predict the core control parameters of the next moment based on real-time data, and then ensure the stability of the action through a smooth transition. First, the first intermediate angle parameter of the next moment after the end of the first transition is calculated by the following formula (7), and the first intermediate angle parameter and the first remaining time are substituted into the above formula (6) to obtain the predicted overall angular velocity.

[0083] (7)

[0084] In the formula, This represents the angle between the centerline and the X-axis at time n. This represents the angle between the centerline and the X-axis at time n-1. This represents the overall angular velocity at time n-1; Indicates the time step; This represents the angle between the horizontal projection at time n and the X-axis; This represents the coordinate of the center of the cross-section of the arrow body at the lower end of the recovery hook on the Z-axis at time n. This represents the coordinate of the center of the cross-section of the arrow body at the lower end of the recovery hook on the X-axis at time n. This represents the angle between the horizontal projection and the center line at time n.

[0085] To avoid abrupt changes in the robotic arm's movements due to parameter updates, a parabolic transition algorithm is still used to achieve transitions in both the included angle parameter and the angular velocity: the angular velocity smoothly switches from the overall angular velocity at the end of the first transition to the predicted overall angular velocity at the next moment, gradually transitioning according to a parabolic law to ensure continuous and shock-free velocity changes; the included angle parameter is gradually adjusted from the included angle parameter at the end of the first transition to the target posture corresponding to the first intermediate included angle parameter, so that the robotic arm's posture naturally adapts with the angular velocity adjustment, avoiding asynchrony between posture and velocity movements.

[0086] Step a8: Continue to calculate the first remaining time, the first intermediate angle parameter, and the overall angular velocity at the next moment, and control the robotic arm accordingly until the retrieval hook is at the second height of the robotic arm.

[0087] Specifically, in the first stage of stable alignment, the rocket to be recovered continues to fall and its state changes dynamically. By repeating step a6 above, the first remaining time for the next moment is calculated, and step a7 is repeated until the recovery hook is at the second height of the robotic arm, ensuring that the robotic arm always tracks the rocket's position and gradually eliminates the alignment deviation. As can be seen from the above formula (7), the angle between the centerline and the X-axis will gradually adjust with the continuous action of the overall angular velocity, while the angle between the horizontal projection and the centerline will gradually decrease, eventually reaching 0 at the end of the first stage. At this time, the rocket to be recovered is located on the centerline of the robotic arm.

[0088] By calculating the first total descent time and using this total duration as a time benchmark, combined with the angle between the horizontal projection and the centerline at the start of control, the angular velocity of the robotic arm at the start of control is derived. This angular velocity directly binds the initial deviation to be eliminated to the total duration of the first stage, ensuring that the robotic arm has a velocity benchmark from the start stage to completely eliminate the deviation within the total time. During dynamic alignment, the first remaining time and the angle between the horizontal projection and the centerline are updated in real time based on the real-time state parameters of the rocket to be recovered, and the overall angular velocity of the robotic arm is corrected based on the updated parameters. At the same time, a parabolic transition algorithm is used to achieve smooth switching of the robotic arm's angular velocity and synchronous adaptation of the angle parameters. This ensures that the angle between the horizontal projection and the centerline gradually decreases as the recovery hook falls, and finally, when the recovery hook reaches the second height, the alignment deviation is accurately eliminated, completing the dynamic alignment task.

[0089] Step S208: Obtain the target angle parameter when the retrieval hook is at the second height from the robotic arm. The robotic arm includes a left robotic arm and a right robotic arm.

[0090] Specifically, when the recovery hook of the rocket to be recovered descends to the second height from the robotic arm, the first stage ends and the second stage is about to begin. At this point, it is necessary to obtain the target angle parameter at that moment. This parameter is the reference for the robotic arm to switch from the centering state to the closed state in the second stage. The core of the target angle parameter is the angle between the centerline of the robotic arm and the X-axis when the recovery hook reaches the second height, reflecting the reference attitude of the robotic arm at the end of the centering stage.

[0091] Step S209: Based on the target angle parameters and the state parameters of the rocket to be recovered at the start of control, calculate the first initial angle parameters of the left robotic arm and the second initial angle parameters of the right robotic arm.

[0092] Specifically, in the first stage, the left and right robotic arms rotate as a whole with the set opening angle unchanged to ensure that the opening posture of the robotic arms is stable during the centering process. The goal of the second stage is to make the left and right robotic arms gradually close from the current opening posture to the opening angle of 0. Therefore, it is necessary to determine the initial angle parameters of the left and right robotic arms respectively through the following formula (8), accurately split the initial posture of the left and right robotic arms, and ensure that the two arms start the closing action with a symmetrical opening angle.

[0093] (8)

[0094] In the formula, This indicates the angle between the left robotic arm and the X-axis; This represents the angle between the centerline and the X-axis in the target angle parameter; This indicates the angle of the robotic arm at the moment of activation; This indicates the angle between the right robotic arm and the X-axis.

[0095] Step S210: Obtain the target overall angular velocity at the previous moment when the distance between the retrieval hook and the second height of the robotic arm, and use the target overall angular velocity as the first initial angular velocity of the left robotic arm and the second initial angular velocity of the right robotic arm.

[0096] Specifically, when the second stage starts, the left and right robotic arms need to switch from the overall synchronous rotation of the first stage to differentiated combined arm rotation. The angular velocity before the end of the first stage is the key connection reference for the starting angular velocity of the second stage. Therefore, it is necessary to obtain the angular velocity of the previous moment when the recovery hook reaches the second height as the target overall angular velocity and use it directly as the initial angular velocity of the left and right robotic arms. This can achieve a seamless connection of the speed of the two arms from overall rotation to combined arm rotation.

[0097] Step S211: When the retrieval hook is at the second height from the robotic arm, control the robotic arm to dynamically close, so that the robotic arm completes the closing when the retrieval hook is at the third height from the robotic arm.

[0098] Specifically, step S211 includes:

[0099] Step b1: When the recovery hook is at the second height from the robotic arm, calculate the second total descent time based on the state parameters of the rocket to be recovered at the start of the phase.

[0100] Specifically, when the recovery hook is at the second height of the robotic arm, the first stage ends and the second stage begins, with the current moment being the start time of the stage. To ensure that the closing action of the robotic arm in the second stage can be precisely matched with the rocket's descent progress, the second total descent time must be calculated based on the state parameters of the rocket to be recovered at the start time of this stage using the following formula (9). This is the predicted time required for the recovery hook to descend from the second height to the third height, and serves as the time reference for subsequently planning the angular velocity of the left and right robotic arms to close, ensuring that the closing action can be completed within the total duration of the stage. Only by clarifying the second total descent time can we further plan the angular velocity at which the left and right robotic arms need to rotate to complete the closing action at the end of the stage, avoiding the closing action being too early or too late due to a vague time reference, and ensuring that the closing action is completely synchronized with the rocket's descent process.

[0101] (9)

[0102] In the formula, Indicates the second total descent time; Indicates the third altitude; This indicates the velocity of the rocket body to be recovered along the Y-axis at the start of the phase.

[0103] Step b2: Based on the target angle parameter, the first initial angle parameter, and the second initial angle parameter, calculate the angle parameters of the left robotic arm and the right robotic arm at the start of the stage, respectively.

[0104] Specifically, the angle parameters of the left and right robotic arms at the start of the phase can be calculated separately using the following formula (10), which can accurately locate the relative position of the left and right robotic arms with respect to the rocket core and clarify the initial deviation of the left and right robotic arms when they start in the arm-joining phase.

[0105] (10)

[0106] In the formula, The angle between the line connecting the center of the rocket to be recovered to the origin at the start of the phase and the left or right robotic arm. This indicates the angle between the horizontal projection at the start of the phase and the X-axis.

[0107] In some optional implementations, the above formula (10) is a general calculation formula for the left and right robotic arms. That is, when calculating the angle between the line connecting the arrow center and the origin and the left robotic arm, only the angle between the horizontal projection at the start of the stage and the X-axis, and the angle between the left robotic arm and the X-axis, are substituted; when calculating the angle between the line connecting the arrow center and the origin and the right robotic arm, only the angle between the horizontal projection at the start of the stage and the X-axis, and the angle between the right robotic arm and the X-axis, are substituted. All formulas involved in steps b3-b8 below are general formulas for the left and right robotic arms, and can be substituted accordingly during calculation.

[0108] Step b3: Based on the second total descent time and the angle parameters of the left and right robotic arms at the start of the phase, predict the first transition angular velocity of the left robotic arm and the second transition angular velocity of the right robotic arm, respectively.

[0109] Specifically, in the initial stage of the second phase, the robotic arm needs to switch from the synchronous overall rotation of the left and right arms in the first phase to differentiated combined rotation of the left and right arms. To avoid sudden changes in angular velocity causing impacts to the robotic arm's drive components, structural vibrations, or misalignment of centering accuracy, a smooth transition between actions needs to be achieved through transition control. Determine the first transition angular velocity of the left robotic arm and the second transition angular velocity of the right robotic arm.

[0110] Step b4: Determine the second transition time based on the second total descent time. During the second transition time, control the left robotic arm to transition from the first initial angular velocity to the first transition angular velocity using a parabolic transition algorithm, and control the right robotic arm to transition from the second initial angular velocity to the second transition angular velocity.

[0111] Specifically, to achieve a smooth transition between the left and right robotic arms from the first stage overall rotational angular velocity to the second stage arm-closing transition angular velocity, the following will be implemented: The second transition time is determined to ensure that the left and right robotic arms have sufficient time to complete the angular velocity switching, achieving a balance between structural stability and arm closing timeliness. During the second transition time, the parabolic transition algorithm used in the first stage is referenced to achieve a smooth transition of angular velocity. The real-time angular velocity of the left and right robotic arms at each moment during the transition stage can be calculated using the following formula (11). Taking the second transition time as the time reference, the initial angular velocity of the left and right robotic arms as the starting point and the transition angular velocity as the ending point, the real-time velocity is planned according to the parabolic law, that is, the initial angular velocity rises slowly and gradually approaches the target velocity in the later stage, forming a continuous velocity curve without sudden changes. The robotic arm drive system will dynamically adjust according to the real-time angular velocity to ensure that the left and right robotic arms reach the corresponding transition angular velocity at the end of the second transition time.

[0112] (11)

[0113] In the formula, This indicates the first initial angular velocity of the left robotic arm or the second initial angular velocity of the right robotic arm; This indicates the first transition angular velocity of the left robotic arm or the second transition angular velocity of the right robotic arm; Indicates the start time of the second transition period; This indicates the second transition time.

[0114] In some optional implementations, when the left and right robotic arms rotate in real time according to the above formula (11), the angle between them and the X-axis will be dynamically updated as the angular velocity changes. If only the angular velocity is adjusted and the angle is not calculated synchronously, it is easy to cause the actual posture of the robotic arm to deviate from the target arm-joining posture. Therefore, the angle value corresponding to the real-time angular velocity of the left and right robotic arms needs to be determined by the following formula (12) to ensure that the posture of the left and right robotic arms is accurately updated while the speed is adjusted according to the parabolic transition algorithm, so as to avoid the speed and posture movement being out of sync.

[0115] (12)

[0116] Step b5: Based on the state parameters of the rocket to be recovered at the end of the second transition time, calculate the second remaining time, the angle parameters and angular velocity of the left robotic arm, and the angle parameters and angular velocity of the right robotic arm corresponding to the end of the second transition time. The second remaining time represents the time it takes for the recovery hook to descend from the current altitude to the third altitude.

[0117] Specifically, at the end of the second transition time, the left and right robotic arms need to switch from the starting state with a smooth transition in angular velocity to the closed-arm state. To this end, it is necessary to obtain the core control parameters of the left and right robotic arms at the end of the second transition time. Based on these parameters, subsequent closed-arm actions are performed to ensure that the subsequent closed-arm actions are fully matched with the current dynamics of the rocket, avoiding the risk of closed-arm deviation or rocket collision due to parameter lag. Taking the left robotic arm as an example, from the state parameters of the rocket to be recovered obtained at the end of the second transition time, the height of the recovery hook from the robotic arm and the velocity of the rocket body on the Y-axis are obtained and substituted into the above formula (9) to obtain the remaining time for the recovery hook to descend from the current height to the third height, which is the second remaining time. Then, the end of the second transition time is substituted into the above formula (12) to obtain the angle between the left robotic arm and the X-axis at the end of the second transition time. Then, from the state parameters at the end of the second transition, obtain the angle between the centerline of the robotic arm and the X-axis. Combine this with the angle between the left robotic arm and the X-axis at the end of the second transition, and substitute them into the above formula (10) to obtain the angle between the line connecting the arrow center and the origin at the end of the second transition and the left robotic arm, thus quantifying the relative deviation between the current left robotic arm and the rocket to be recovered. Finally, substitute the angle between the first remaining time corresponding to the end of the second transition and the horizontal projection and the centerline into the following formula (13) to obtain the angular velocity of the left robotic arm at the end of the second transition, ensuring that this angular velocity can gradually eliminate the relative deviation between the left robotic arm and the rocket within the remaining time, thus meeting the requirements for stable arm reassembly. Optionally, the calculation process of the angular velocity of the right robotic arm is the same as that of the left robotic arm, and will not be repeated here.

[0118] (13)

[0119] In the formula, This represents the angular velocity of the left or right robotic arm at time j. This represents the angular velocity of the left or right robotic arm at time j-1. This represents the second remaining time at time j.

[0120] Step b6: Based on the second remaining time corresponding to the end of the second transition, the included angle parameters and angular velocity of the left robotic arm, the included angle parameters and angular velocity of the right robotic arm, and the state parameters of the rocket to be recovered at the next moment, calculate the second remaining time corresponding to the next moment.

[0121] Specifically, after entering the arm-closing state in the second stage, refer to step b5 to calculate the second remaining time, calculate the second remaining time corresponding to the next moment after the end of the second transition, and ensure that the second remaining time always matches the actual descent progress of the rocket, so as to provide a reliable time basis for the dynamic planning of the angular velocity of the left and right robotic arms in the subsequent arm-closing phase.

[0122] Step b7: Based on the state parameters and the second remaining time at the next moment, predict the second intermediate angle parameters and angular velocity of the left robotic arm and the third intermediate angle parameters and angular velocity of the right robotic arm at the next moment. Control the angle parameters and angular velocity of the left robotic arm to transition to the corresponding second intermediate angle parameters and angular velocity respectively through the parabolic transition algorithm, and control the angle parameters and angular velocity of the right robotic arm to transition to the corresponding third intermediate angle parameters and angular velocity respectively.

[0123] Specifically, in order to achieve precise matching of the dynamic positions of the left and right robotic arms with the rocket during the stable arm-closing process, it is necessary to first predict the core control parameters for the next moment based on real-time data, and then ensure the stability of the action through a smooth transition. First, the second intermediate angle parameter of the left robotic arm and the third intermediate angle parameter of the right robotic arm at the next moment after the end of the second transition are calculated by the following formula (14). At the same time, the second intermediate angle parameter, the third intermediate angle parameter and the second remaining time are substituted into the above formula (13) to obtain the predicted angular velocities of the left and right robotic arms.

[0124] (14)

[0125] In the formula, This represents the angle between the left or right robotic arm and the X-axis at time j. This represents the angle between the left or right robotic arm and the X-axis at time j-1. This represents the angular velocity of the left or right robotic arm at time j-1. This represents the angle between the horizontal projection at time j and the X-axis; This represents the angle between the line connecting the arrow's center and the origin at time j and either the left or right robotic arm.

[0126] To avoid sudden changes in angular velocity or posture lag caused by parameter updates in the left and right robotic arms, a parabolic transition algorithm is still used to achieve transitions in the included angle parameter and angular velocity respectively, ensuring continuous and shock-free speed changes. At the same time, the postures of the left and right robotic arms are naturally adapted to the angular velocity adjustment, avoiding asynchrony between posture and speed movement.

[0127] Step b8: Continue to calculate the second remaining time, the second intermediate angle parameter and angular velocity of the left robotic arm and the third intermediate angle parameter and angular velocity of the right robotic arm corresponding to the next moment, and perform corresponding control on the left and right robotic arms until the retrieval hook is at the third height of the robotic arm.

[0128] Specifically, in the second stage of the arm-closing process, the rocket to be recovered continues to fall and its state changes dynamically. By repeating step b6 above to calculate the second remaining time at the next moment and step b7, until the recovery hook is at the third height of the robotic arm, the relative deviation between the left and right robotic arms and the rocket is gradually eliminated. As can be seen from the above formula (14), the angle between the left and right robotic arms and the X-axis will gradually increase as the arms close, while the angle between the line connecting the rocket center and the origin and the left or right robotic arm will gradually decrease. Finally, at the end of the second stage, both angles reach 0, the left and right robotic arms are completely closed, and the arm closure is completed.

[0129] By calculating the second total descent time and using this total duration as a time benchmark, combined with the angle between the line connecting the arrow's center and the origin at the start of the phase and the left and right robotic arms, the angular velocities of the left and right robotic arms at the start of the phase are derived. This angular velocity directly binds the initial deviation to be eliminated to the total duration of the second phase, ensuring that the left and right robotic arms have a velocity benchmark from the start of the phase to completely eliminate the deviation within the total time. During the arm-closing process, the real-time status parameters of the rocket to be recovered are constantly used to update the second remaining time and the angle between the line connecting the arrow's center and the origin and the left or right robotic arm, and the angular velocities of the left and right robotic arms are corrected based on the updated parameters. At the same time, a parabolic transition algorithm is used to achieve smooth switching of the robotic arm angular velocities and synchronous adaptation of the angle parameters. The angle between the line connecting the arrow's center and the origin and the left or right robotic arm gradually decreases as the recovery hook falls, and finally, when the recovery hook reaches the third height, the relative deviation between the left and right robotic arms and the rocket is precisely eliminated, completing the robotic arm closure.

[0130] Step S212: When the recovery hook is at the third height from the robotic arm, the state of the robotic arm remains unchanged until the rocket to be recovered falls onto the robotic arm. For details, please refer to [link to details]. Figure 1 Step S104 of the illustrated embodiment will not be described again here.

[0131] In some alternative implementations, Figure 4 This is a schematic diagram of the three stages of rocket recovery according to an embodiment of the present invention, as shown below. Figure 4 As shown, in the first stage of rocket recovery, the robotic arm dynamically centers the rocket to be recovered, and at the end of the first stage, the rocket is positioned on the center line of the robotic arm. In the second stage, the left and right robotic arms are controlled to close together, and the closure is completed at the end of the second stage. In the third stage, the robotic arms are not controlled, and their state remains unchanged until the recovery hook of the rocket falls onto the robotic arm, completing the rocket recovery.

[0132] In some alternative implementations, Figure 5 This is a flowchart of another control method for a rocket recovery tower robotic arm according to an embodiment of the present invention, such as... Figure 5As shown, the system acquires the real-time status parameters of the rocket to be recovered. When the recovery hook of the rocket is at a first height from the robotic arm, control of the robotic arm is triggered, entering the first stage of rocket recovery. Based on the real-time acquired status parameters, the first total descent time of the first stage is predicted. After the first transition time, the first intermediate angle parameter and overall angular velocity of the robotic arm are continuously calculated to control the robotic arm accordingly. When the recovery hook is at a second height from the robotic arm, the first stage ends, and the target angle parameter and target overall angular velocity are acquired as the calculation basis for the second stage. In the second stage, based on the real-time acquired status parameters, the second total descent time of the second stage is predicted. After the second transition time, the intermediate angle parameters and angular velocities of the left and right robotic arms are continuously calculated to control the left and right robotic arms respectively. When the recovery hook is at a third height from the robotic arm, the second stage ends, and the third stage begins. In the third stage, no control is applied to the robotic arm; its state remains unchanged until the recovery hook lands on the robotic arm. The third stage ends, completing the recovery of the rocket.

[0133] This invention acquires the real-time status parameters of the rocket to be recovered, ensuring that the robotic arm control can dynamically adjust according to the actual descent of the rocket. It also correlates the robotic arm's actions during rocket capture with the rocket's real-time status, adapting to different return trajectories and preventing collisions between the robotic arm and the rocket during recovery, thus improving the safety of rocket recovery. When the recovery hook reaches the first altitude, the robotic arm is dynamically aligned so that the rocket is on the robotic arm's centerline when the hook reaches the second altitude, reducing the difficulty of closing the arm. When the hook reaches the second altitude, the robotic arm dynamically closes, completing the closure when the hook reaches the third altitude, effectively ensuring that the rocket lands on the robotic arm during its vertical descent. When the hook reaches the third altitude, the robotic arm maintains its position until the rocket lands on it, completing a reliable rocket recovery.

[0134] This embodiment also provides a control device for a rocket recovery tower robotic arm, which implements the above embodiments and preferred embodiments; details already described will not be repeated. As used below, the term "module" can refer to a combination of software and / or hardware that performs a predetermined function. Although the devices described in the following embodiments are preferably implemented in software, hardware implementation, or a combination of software and hardware, is also possible and contemplated.

[0135] This embodiment provides a control device for a rocket recovery tower robotic arm, such as... Figure 6 As shown, it includes:

[0136] The first acquisition module 601 is used to acquire the status parameters of the rocket to be recovered in real time, including the height of the recovery hook of the rocket from the robotic arm.

[0137] The first control module 602 is used to trigger the control of the robotic arm when the recovery hook of the rocket to be recovered is at a first height from the robotic arm, and to control the robotic arm to dynamically center the rocket to be recovered so that when the recovery hook is at a second height from the robotic arm, the rocket to be recovered is located on the center line of the robotic arm.

[0138] The second control module 603 is used to control the robotic arm to dynamically close when the retrieval hook is at a second height from the robotic arm, so that the robotic arm completes the closing when the retrieval hook is at a third height from the robotic arm.

[0139] The third control module 604 is used to keep the state of the robotic arm unchanged when the recovery hook is at a third height from the robotic arm, until the rocket to be recovered falls onto the robotic arm.

[0140] In some alternative embodiments, after the first acquisition module 601, the device further includes:

[0141] The first determining module is used to take the rotation center of the robotic arm as the origin.

[0142] The second determining module is used to take the length direction of the robotic arm when it is in the zero position of the arm closing as the X-axis.

[0143] The third determining module is used to take the direction perpendicular to the X-axis as the Y-axis.

[0144] The fourth determination module is used to determine the Z-axis based on the X-axis and Y-axis using the right-hand rule.

[0145] Establish a module to create a tower coordinate system based on the origin, X-axis, Y-axis, and Z-axis.

[0146] In some alternative implementations, the first control module 602 includes:

[0147] The first calculation unit is used to calculate the first total descent time and the angle parameter between the start and start times based on the state parameters of the rocket to be recovered at the start of control when the recovery hook is at the first height of the robotic arm.

[0148] The second calculation unit is used to calculate the angular velocity at the start of control based on the angle parameters between the first total descent time and the start of control.

[0149] The third calculation unit is used to determine the first transition time based on the first total descent time and to calculate the first transition angular velocity based on the angular velocity at the start of control.

[0150] The first control unit is used to control the angular velocity of the robotic arm to transition to the first transition angular velocity through a parabolic transition algorithm during the first transition time.

[0151] The fourth calculation unit is used to calculate the first remaining time, included angle parameter and overall angular velocity corresponding to the first transition end time of the rocket to be recovered based on the state parameters of the rocket to be recovered at the first transition end time of the first transition time. The first remaining time represents the time it takes for the recovery hook to descend from the current altitude to the second altitude.

[0152] The fifth calculation unit is used to calculate the first remaining time corresponding to the next moment based on the first remaining time corresponding to the end of the first transition, the included angle parameter and the overall angular velocity, as well as the state parameters of the rocket to be recovered at the next moment.

[0153] The second control unit is used to predict the first intermediate angle parameter and the overall angular velocity of the robotic arm at the next moment based on the state parameters of the next moment and the first remaining time, and to control the angle parameter and angular velocity of the robotic arm to transition to the corresponding first intermediate angle parameter and overall angular velocity respectively through a parabolic transition algorithm.

[0154] The third control unit is used to continue calculating the first remaining time, the first intermediate angle parameter, and the overall angular velocity corresponding to the next moment, and to control the robotic arm accordingly until the retrieval hook is at the second height of the robotic arm.

[0155] In some optional implementations, the included angle parameter at the start-up time is calculated using the following formula:

[0156]

[0157] In the formula, Indicates the angle between the centerline at the moment of control activation and the X-axis; The angle between the horizontal projection at the moment of control activation and the X-axis; This indicates the coordinate of the center of the cross-section of the arrow body at the lower end of the recovery hook on the Z-axis at the moment of activation. This indicates the coordinate of the center of the cross-section of the arrow body at the lower end of the recovery hook on the X-axis at the moment of activation. The angle between the horizontal projection at the moment of activation and the centerline;

[0158] The first intermediate angle parameter is calculated using the following formula:

[0159]

[0160] In the formula, This represents the angle between the centerline and the X-axis at time n. This represents the angle between the centerline and the X-axis at time n-1. This represents the overall angular velocity at time n-1; Indicates the time step; This represents the angle between the horizontal projection at time n and the X-axis; This represents the coordinate of the center of the cross-section of the arrow body at the lower end of the recovery hook on the Z-axis at time n. This represents the coordinate of the center of the cross-section of the arrow body at the lower end of the recovery hook on the X-axis at time n. This represents the angle between the horizontal projection and the centerline at time n.

[0161] The overall angular velocity is calculated using the following formula:

[0162]

[0163] In the formula, This represents the overall angular velocity at time n; Indicates the low-pass filter coefficients; Indicates the angular velocity at the moment of control activation; This represents the first remaining time at time n.

[0164] In some alternative implementations, the robotic arm includes a left robotic arm and a right robotic arm;

[0165] The device also includes:

[0166] The second acquisition module is used to acquire the target angle parameter when the recovery hook is at a second height from the robotic arm.

[0167] The calculation module is used to calculate the first initial angle parameter of the left robotic arm and the second initial angle parameter of the right robotic arm based on the target angle parameter and the state parameters of the rocket to be recovered at the start of control.

[0168] The determination module is used to obtain the target's overall angular velocity at the previous moment when the retrieval hook is at the second height from the robotic arm, and to use the target's overall angular velocity as the first initial angular velocity of the left robotic arm and the second initial angular velocity of the right robotic arm.

[0169] In some optional implementations, the first initial included angle parameter and the second initial included angle parameter are calculated using the following formula:

[0170]

[0171] In the formula, This indicates the angle between the left robotic arm and the X-axis; This represents the angle between the centerline and the X-axis in the target angle parameter; This indicates the angle of the robotic arm at the moment of activation; This indicates the angle between the right robotic arm and the X-axis.

[0172] In some alternative implementations, the second control module 603 includes:

[0173] The sixth calculation unit is used to calculate the second total descent time based on the state parameters of the rocket to be recovered at the start of the stage when the recovery hook is at the second height of the robotic arm.

[0174] The seventh calculation unit is used to calculate the angle parameters of the left robotic arm and the right robotic arm at the start of the stage, based on the target angle parameter, the first initial angle parameter, and the second initial angle parameter.

[0175] The eighth calculation unit is used to predict the first transition angular velocity of the left robotic arm and the second transition angular velocity of the right robotic arm based on the second total descent time, the angle parameters of the left robotic arm and the right robotic arm at the start of the phase.

[0176] The fourth control unit is used to determine the second transition time based on the second total descent time. During the second transition time, the left robotic arm is controlled to transition from the first initial angular velocity to the first transition angular velocity using a parabolic transition algorithm, and the right robotic arm is controlled to transition from the second initial angular velocity to the second transition angular velocity.

[0177] The ninth calculation unit is used to calculate the second remaining time, the angle parameters and angular velocity of the left robotic arm and the right robotic arm corresponding to the second transition end time of the rocket to be recovered based on the state parameters of the rocket at the second transition end time of the second transition time. The second remaining time represents the time it takes for the recovery hook to descend from the current altitude to the third altitude.

[0178] The tenth calculation unit is used to calculate the second remaining time corresponding to the next moment based on the second remaining time corresponding to the end of the second transition, the included angle parameters and angular velocity of the left robotic arm, the included angle parameters and angular velocity of the right robotic arm, and the state parameters of the rocket to be recovered at the next moment.

[0179] The fifth control unit is used to predict the second intermediate angle parameter and angular velocity of the left robotic arm and the third intermediate angle parameter and angular velocity of the right robotic arm based on the state parameters and the second remaining time at the next moment. It controls the angle parameter and angular velocity of the left robotic arm to transition to the corresponding second intermediate angle parameter and angular velocity respectively through a parabolic transition algorithm, and controls the angle parameter and angular velocity of the right robotic arm to transition to the corresponding third intermediate angle parameter and angular velocity respectively.

[0180] The sixth control unit is used to continue calculating the second remaining time, the second intermediate angle parameter and angular velocity of the left robotic arm and the third intermediate angle parameter and angular velocity of the right robotic arm corresponding to the next moment, and to control the left and right robotic arms accordingly until the retrieval hook is at the third height of the robotic arm.

[0181] In some alternative implementations, the included angle parameter of the left robotic arm or the included angle parameter of the right robotic arm at the start of the phase is calculated using the following formula:

[0182]

[0183] In the formula, The angle between the line connecting the center of the rocket to be recovered to the origin at the start of the phase and the left or right robotic arm. The angle between the horizontal projection at the start of the phase and the X-axis;

[0184] The second or third intermediate angle parameter is calculated using the following formula:

[0185]

[0186] In the formula, This represents the angle between the left or right robotic arm and the X-axis at time j. This represents the angle between the left or right robotic arm and the X-axis at time j-1. This represents the angular velocity of the left or right robotic arm at time j-1. This represents the angle between the horizontal projection at time j and the X-axis; This represents the angle between the line connecting the arrow's center and the origin at time j and either the left or right robotic arm.

[0187] Angular velocity or angular speed is calculated using the following formula:

[0188]

[0189] In the formula, This represents the angular velocity of the left or right robotic arm at time j. This represents the angular velocity of the left or right robotic arm at time j-1. This represents the second remaining time at time j.

[0190] The control device for the rocket recovery tower robotic arm provided in this embodiment of the invention can execute the control method for the rocket recovery tower robotic arm provided in any embodiment of the invention, and has the corresponding functional modules and beneficial effects of the method. Further functional descriptions of the above modules and units are the same as in the corresponding embodiments described above, and will not be repeated here.

[0191] Figure 7 This is a schematic diagram of the structure of an electronic device provided in an embodiment of the present invention.

[0192] The following is a detailed reference. Figure 7This diagram illustrates a suitable structural schematic for implementing an electronic device according to embodiments of the present invention. The electronic device may include a processor (e.g., a central processing unit, graphics processor, etc.) 701, which can perform various appropriate actions and processes based on a program stored in read-only memory (ROM) 702 or a program loaded from memory 708 into random access memory (RAM) 703. The RAM 703 also stores various programs and data required for the operation of the electronic device. The processor 701, ROM 702, and RAM 703 are interconnected via a bus 704. An input / output (I / O) interface 705 is also connected to the bus 704.

[0193] Typically, the following devices can be connected to I / O interface 705: input devices 706 including, for example, touchscreens, touchpads, keyboards, mice, cameras, microphones, accelerometers, gyroscopes, etc.; output devices 707 including, for example, liquid crystal displays (LCDs), speakers, vibrators, etc.; memory devices 708 including, for example, magnetic tapes, hard disks, etc.; and communication devices 709. Communication device 709 allows electronic devices to exchange data via wireless or wired communication with other devices. Although Figure 7 Electronic devices with various devices are shown, but it should be understood that it is not required to implement or have all of the devices shown, and more or fewer devices may be implemented or have instead.

[0194] In particular, according to embodiments of the present invention, the processes described above with reference to the flowcharts can be implemented as computer software programs. For example, embodiments of the present invention include a computer program product comprising a computer program carried on a non-transitory computer-readable medium, the computer program containing program code for performing the methods shown in the flowcharts. In such embodiments, the computer program can be downloaded and installed from a network via a communication device 709, or installed from a memory 708, or installed from a ROM 702. When the computer program is executed by the processor 701, it performs the functions defined in the rocket recovery tower robotic arm control method of the embodiments of the present invention.

[0195] Figure 7 The electronic device shown is merely an example and should not be construed as limiting the functionality and scope of use of the embodiments of the present invention.

[0196] This invention also provides a computer-readable storage medium. The methods described above according to embodiments of the invention can be implemented in hardware or firmware, or implemented as computer code that can be recorded on a storage medium, or implemented as computer code downloaded via a network and originally stored on a remote storage medium or a non-transitory machine-readable storage medium and then stored on a local storage medium. Thus, the methods described herein can be processed by software stored on a storage medium using a general-purpose computer, a dedicated processor, or programmable or dedicated hardware. The storage medium can be a magnetic disk, optical disk, read-only memory, random access memory, flash memory, hard disk, or solid-state drive, etc.; further, the storage medium can also include combinations of the above types of memory. It is understood that computers, processors, microprocessor controllers, or programmable hardware include storage components capable of storing or receiving software or computer code. When the software or computer code is accessed and executed by the computer, processor, or hardware, the tower robotic arm control method for rocket recovery shown in the above embodiments is implemented.

[0197] A portion of this invention can be applied as a computer program product, such as computer program instructions, which, when executed by a computer, can invoke or provide the methods and / or technical solutions according to the invention through the operation of the computer. Those skilled in the art will understand that the forms in which computer program instructions exist in a computer-readable medium include, but are not limited to, source files, executable files, installation package files, etc. Correspondingly, the ways in which computer program instructions are executed by a computer include, but are not limited to: the computer directly executing the instructions, or the computer compiling the instructions and then executing the corresponding compiled program, or the computer reading and executing the instructions, or the computer reading and installing the instructions and then executing the corresponding installed program. Here, the computer-readable medium can be any available computer-readable storage medium or communication medium accessible to a computer.

[0198] Although embodiments of the invention have been described in conjunction with the accompanying drawings, those skilled in the art can make various modifications and variations without departing from the spirit and scope of the invention, and such modifications and variations all fall within the scope defined by the appended claims.

Claims

1. A control method for a robotic arm on a rocket recovery tower, characterized in that, The method includes: The status parameters of the rocket to be recovered are acquired in real time, including the height of the recovery hook of the rocket from the robotic arm; When the recovery hook is at a first height from the robotic arm, control of the robotic arm is triggered to dynamically center the rocket to be recovered, so that when the recovery hook is at a second height from the robotic arm, the rocket to be recovered is located on the centerline of the robotic arm; When the retrieval hook is at the second height from the robotic arm, the robotic arm is controlled to dynamically close, so that the robotic arm completes the closing when the retrieval hook is at the third height from the robotic arm; When the recovery hook is at the third height of the robotic arm, the state of the robotic arm is kept unchanged until the rocket to be recovered falls onto the robotic arm. Wherein, when the recovery hook is at a first height from the robotic arm, the control of the robotic arm is triggered to dynamically center the robotic arm on the rocket to be recovered, so that when the recovery hook is at a second height from the robotic arm, the rocket to be recovered is located on the centerline of the robotic arm, including: When the recovery hook is at the first height of the robotic arm, the first total descent time and the angle parameter between the launch time are calculated based on the state parameters of the rocket to be recovered at the launch control moment; Based on the angle parameter between the first total descent time and the start-up time, calculate the angular velocity at the start-up time; The first transition time is determined based on the first total descent time, and the first transition angular velocity is calculated based on the angular velocity at the start time. During the first transition time, the angular velocity of the robotic arm is controlled to transition to the first transition angular velocity using a parabolic transition algorithm; Based on the state parameters of the rocket to be recovered at the first transition end time of the first transition time, calculate the first remaining time, the included angle parameter and the overall angular velocity corresponding to the first transition end time. The first remaining time represents the time it takes for the recovery hook to descend from the current altitude to the second altitude. Based on the first remaining time, included angle parameter, and overall angular velocity corresponding to the first transition end time, as well as the state parameters of the rocket to be recovered at the next moment, calculate the first remaining time corresponding to the next moment. Based on the state parameters of the next moment and the first remaining time, the first intermediate angle parameter and the overall angular velocity of the robotic arm at the next moment are predicted. The angle parameter and angular velocity of the robotic arm are controlled to transition to the corresponding first intermediate angle parameter and overall angular velocity through a parabolic transition algorithm. Continue to calculate the first remaining time, the first intermediate angle parameter, and the overall angular velocity corresponding to the next moment, and control the robotic arm accordingly until the retrieval hook is at the second height of the robotic arm.

2. The method according to claim 1, characterized in that, After acquiring the state parameters of the rocket to be recovered in real time, the method further includes: Take the rotation center of the robotic arm as the origin; The length direction of the robotic arm when it is in the zero-position of the arm is taken as the X-axis; The direction perpendicular to the X-axis and upwards is taken as the Y-axis; Based on the X-axis and the Y-axis, the Z-axis is determined using the right-hand rule; A tower coordinate system is established based on the origin, the X-axis, the Y-axis, and the Z-axis.

3. The method according to claim 2, characterized in that, The included angle parameter at the moment of activation is calculated using the following formula: In the formula, Indicates the angle between the centerline at the moment of control activation and the X-axis; The angle between the horizontal projection at the moment of control activation and the X-axis; This indicates the coordinate of the center of the cross-section of the arrow body at the lower end of the recovery hook on the Z-axis at the moment of activation. This indicates the coordinate of the center of the cross-section of the arrow body at the lower end of the recovery hook on the X-axis at the moment of activation. The angle between the horizontal projection at the moment of activation and the centerline; The first intermediate angle parameter is calculated using the following formula: In the formula, This represents the angle between the centerline and the X-axis at time n. This represents the angle between the centerline and the X-axis at time n-1. This represents the overall angular velocity at time n-1; Indicates the time step; This represents the angle between the horizontal projection at time n and the X-axis; This represents the coordinate of the center of the cross-section of the arrow body at the lower end of the recovery hook on the Z-axis at time n. This represents the coordinate of the center of the cross-section of the arrow body at the lower end of the recovery hook on the X-axis at time n. This represents the angle between the horizontal projection and the centerline at time n. The overall angular velocity is calculated using the following formula: In the formula, This represents the overall angular velocity at time n; Indicates the low-pass filter coefficients; Indicates the angular velocity at the moment of control activation; This represents the first remaining time at time n.

4. The method according to claim 2, characterized in that, The robotic arm includes a left robotic arm and a right robotic arm; The method further includes: Obtain the target angle parameter when the retrieval hook is at the second height of the robotic arm; Based on the target angle parameters and the state parameters of the rocket to be recovered at the start of control, calculate the first initial angle parameters of the left robotic arm and the second initial angle parameters of the right robotic arm; The target overall angular velocity at the previous moment is obtained when the distance between the retrieval hook and the second height of the robotic arm is reached. The target overall angular velocity is used as the first initial angular velocity of the left robotic arm and the second initial angular velocity of the right robotic arm.

5. The method according to claim 4, characterized in that, The first initial included angle parameter and the second initial included angle parameter are calculated using the following formula: In the formula, This indicates the angle between the left robotic arm and the X-axis; This represents the angle between the centerline and the X-axis in the target angle parameter; This indicates the angle of the robotic arm at the moment of activation; This indicates the angle between the right robotic arm and the X-axis.

6. The method according to claim 4, characterized in that, The step of controlling the robotic arm to dynamically close when the retrieval hook is at a second height from the robotic arm, and then closing the robotic arm when the retrieval hook is at a third height from the robotic arm, includes: When the recovery hook is at the second height of the robotic arm, the second total descent time is calculated based on the state parameters of the rocket to be recovered at the start of the phase. Based on the target included angle parameter, the first initial included angle parameter, and the second initial included angle parameter, the included angle parameters of the left robotic arm and the right robotic arm at the start of the stage are calculated respectively. Based on the second total descent time, the included angle parameters of the left robotic arm and the right robotic arm at the start of the phase, the first transition angular velocity of the left robotic arm and the second transition angular velocity of the right robotic arm are predicted respectively. The second transition time is determined based on the second total descent time. During the second transition time, the left robotic arm is controlled to transition from the first initial angular velocity to the first transition angular velocity using a parabolic transition algorithm, and the right robotic arm is controlled to transition from the second initial angular velocity to the second transition angular velocity. Based on the state parameters of the rocket to be recovered at the second transition end time of the second transition time, the second remaining time, the included angle parameters and angular velocity of the left robotic arm and the included angle parameters and angular velocity of the right robotic arm are calculated at the second transition end time. The second remaining time represents the time it takes for the recovery hook to descend from the current height to the third height. Based on the second remaining time corresponding to the end of the second transition, the included angle parameters and angular velocity of the left robotic arm, the included angle parameters and angular velocity of the right robotic arm, and the state parameters of the rocket to be recovered at the next moment, calculate the second remaining time corresponding to the next moment; Based on the state parameters and the second remaining time at the next moment, predict the second intermediate angle parameter and angular velocity of the left robotic arm and the third intermediate angle parameter and angular velocity of the right robotic arm at the next moment. Control the angle parameter and angular velocity of the left robotic arm to transition to the corresponding second intermediate angle parameter and angular velocity respectively through the parabolic transition algorithm, and control the angle parameter and angular velocity of the right robotic arm to transition to the corresponding third intermediate angle parameter and angular velocity respectively. Continue to calculate the second remaining time corresponding to the next moment, the second intermediate angle parameter and angular velocity of the left robotic arm, and the third intermediate angle parameter and angular velocity of the right robotic arm, and perform corresponding control on the left robotic arm and the right robotic arm until the retrieval hook is at the third height of the robotic arm.

7. The method according to claim 6, characterized in that, The included angle parameter of the left robotic arm or the included angle parameter of the right robotic arm at the start of the phase is calculated using the following formula: In the formula, The angle between the line connecting the center of the rocket to be recovered to the origin at the start of the phase and the left or right robotic arm. The angle between the horizontal projection at the start of the phase and the X-axis; The second or third intermediate angle parameter is calculated using the following formula: In the formula, This represents the angle between the left or right robotic arm and the X-axis at time j. This represents the angle between the left or right robotic arm and the X-axis at time j-1. This represents the angular velocity of the left or right robotic arm at time j-1. This represents the angle between the horizontal projection at time j and the X-axis; This represents the angle between the line connecting the arrow's center and the origin at time j and either the left or right robotic arm. Angular velocity or angular speed is calculated using the following formula: In the formula, This represents the angular velocity of the left or right robotic arm at time j. This represents the angular velocity of the left or right robotic arm at time j-1. This represents the second remaining time at time j.

8. A control device for a rocket recovery tower robotic arm, characterized in that, The device includes: The first acquisition module is used to acquire the status parameters of the rocket to be recovered in real time, including the height of the recovery hook of the rocket to be recovered from the robotic arm; The first control module is used to trigger the control of the robotic arm when the recovery hook of the rocket to be recovered is at a first height from the robotic arm, and to control the robotic arm to dynamically center the rocket to be recovered so that when the recovery hook is at a second height from the robotic arm, the rocket to be recovered is located on the centerline of the robotic arm. The second control module is used to control the robotic arm to dynamically close when the retrieval hook is at the second height of the robotic arm, so that the robotic arm completes the closing when the retrieval hook is at the third height of the robotic arm; The third control module is used to control the state of the robotic arm to remain unchanged when the recovery hook is at the third height of the robotic arm, until the rocket to be recovered falls onto the robotic arm; The first control module includes: The first calculation unit is used to calculate the first total descent time and the angle parameter between the launch and the launch time based on the state parameters of the rocket to be recovered at the launch time when the recovery hook is at the first height of the robotic arm. The second calculation unit is used to calculate the angular velocity at the start-up time based on the angle parameter between the first total descent time and the start-up time. The third calculation unit is used to determine the first transition time based on the first total descent time, and to calculate the first transition angular velocity based on the angular velocity at the start time. The first control unit is used to control the angular velocity of the robotic arm to transition to the first transition angular velocity through a parabolic transition algorithm during the first transition time. The fourth calculation unit is used to calculate the first remaining time, the included angle parameter and the overall angular velocity corresponding to the first transition end time based on the state parameters of the rocket to be recovered at the first transition end time of the first transition time. The first remaining time represents the time it takes for the recovery hook to descend from the current height to the second height. The fifth calculation unit is used to calculate the first remaining time corresponding to the next moment based on the first remaining time, the included angle parameter, the overall angular velocity, and the state parameters of the rocket to be recovered at the next moment, corresponding to the first remaining time at the end of the first transition. The second control unit is used to predict the first intermediate angle parameter and the overall angular velocity of the robotic arm at the next moment based on the state parameters and the first remaining time, and to control the angle parameter and angular velocity of the robotic arm to transition to the corresponding first intermediate angle parameter and overall angular velocity respectively through a parabolic transition algorithm. The third control unit is used to continue calculating the first remaining time, the first intermediate angle parameter, and the overall angular velocity corresponding to the next moment, and to control the robotic arm accordingly until the retrieval hook is at the second height of the robotic arm.

9. An electronic device, characterized in that, include: A memory and a processor are communicatively connected, the memory storing computer instructions, and the processor executing the computer instructions to perform the tower robotic arm control method for rocket recovery as described in any one of claims 1 to 7.

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