Arresting mechanism and control method for marine recovery of fixed-wing UAV

Abstract

The present invention relates to an arresting mechanism and control method for recovering fixed-wing UAV at sea, wherein a recovery rope height adjustment component is provided with a slider, and a recovery rope steering component is provided on the slider, and the two ends of the recovery rope are respectively wound around the recovery rope steering components on the corresponding side and then wound in the recovery rope retracting and releasing components on the corresponding side; the recovery rope height adjustment component includes a belt, an adjustment drive motor and a sway reduction control module, the belt is driven to move by the adjustment drive motor, and the adjustment drive motor controls the speed through the sway reduction control module, and the slider is fixedly connected to one side of the belt; the recovery rope retracting and releasing component includes a winding wheel, a retracting and releasing drive motor and a flexible variable damping control module, the recovery rope is wound on the winding wheel, and the winding wheel is driven to rotate by the retracting and releasing drive motor, and the retracting and releasing drive motor controls the speed through the flexible variable damping control module. The present invention can reduce the influence of deck sway on the recovery of the UAV and ensure the control accuracy during the recovery of the UAV on water.

Description

Technical Field

[0001] The invention relates to an arresting mechanism and a control method for recovering a fixed-wing unmanned aerial vehicle at sea. Background Art

[0002] The mother-and-child unmanned system consisting of fixed-wing UAVs and surface unmanned ships is a typical cross-domain heterogeneous collaborative implementation method. At the same time, its collaborative control also faces great technical challenges. Targeted research and design can quickly improve the technical level of my country's existing unmanned equipment.

[0003] In recent years, with the rapid development of the concept of drone swarms and related technologies, fixed-wing drone platforms have received a lot of attention. If the drones can be flexibly released and recovered on mother carriers such as the water surface and form coordination with the mother carrier, their combat effectiveness can be greatly improved.

[0004] However, the flight characteristics of fixed-wing aircraft determine that their autonomous release and recovery in complex environments (wind disturbance on the water surface, lateral and longitudinal distances of surface ships, etc.) face great technical challenges, which brings difficulties to the formation of flexible and recyclable cross-domain mother-and-child platforms.

[0005] At present, the methods available for reference mainly include: net recovery and parachute recovery. Net recovery refers to a recovery method in which the drone uses a specific guidance method to slow down and lower its altitude, and finally crashes into the arresting net. The net recovery system is generally composed of an arresting net, an energy absorption buffer device, and a terminal guidance device. The key to recovery is to accurately guide the drone to fly into the arresting net and gently absorb the kinetic energy of the drone, so as to achieve safe recovery. The arresting net woven with elastic materials and the energy absorbers at both ends of the net make the speed of the drone drop to zero quickly after it crashes into the net. However, there are two crucial issues in net recovery: the accuracy of terminal guidance and the energy absorption buffer level of the recovery system. Since the area of ​​the arresting net is not large, the terminal guidance requirements are very high. Once the guidance deviates, the drone will not be able to fly into the arresting net accurately. Parachute recovery is to use a parachute to recover the drone. This recovery method is simple to operate. The entire process from the flight state to the safe recovery of the drone can be completed automatically, and the requirements for operators are relatively low. However, parachute recovery also has many disadvantages: for example, the built-in parachute will take up space and load inside the fuselage; the aircraft descends quickly during landing, and the fuselage will be subjected to a strong impact at the moment of landing, which can easily cause varying degrees of damage. In addition, due to the influence of the environment, it is difficult to accurately control the landing point.

[0006] In summary, how to autonomously recover fixed-wing UAVs has always been a hot topic in this field. Although existing methods can achieve this goal to varying degrees, most of them require harsh external conditions. Therefore, they cannot adapt to harsh environments (such as wind and waves on the water surface), nor can they guarantee the accuracy of the water surface recovery process. Summary of the invention

[0007] The purpose of the present invention is to provide an arresting mechanism and a control method for the recovery of fixed-wing UAVs at sea, which can reduce the influence of deck swaying on the recovery of the UAV and ensure the control accuracy during the recovery of the UAV on water.

[0008] The objective of the present invention is achieved through the following technical solutions:

[0009] A blocking mechanism for recovering fixed-wing unmanned aerial vehicles at sea comprises a recovery rope, a recovery rope height adjustment component, a recovery rope steering component and a recovery rope retracting and releasing component, wherein the recovery rope height adjustment component is provided with a slider, and the recovery rope steering component is provided on the slider, and the two ends of the recovery rope are respectively wound around the recovery rope steering components on the corresponding sides and then placed in the recovery rope retracting and releasing components on the corresponding sides; the recovery rope height adjustment component comprises a belt, an adjustment drive motor and a roll reduction control module, the belt is driven to move by the adjustment drive motor, and the speed of the adjustment drive motor is controlled by the roll reduction control module, and the slider is fixedly connected to one side of the belt; the recovery rope retracting and releasing component comprises a winding wheel, a retracting and releasing drive motor and a flexible variable damping control module, the recovery rope is wound around the winding wheel, and the winding wheel is driven to rotate by the retracting and releasing drive motor, and the speed of the retracting and releasing drive motor is controlled by the flexible variable damping control module.

[0010] The recovery rope height adjustment component and the recovery rope retracting component are both arranged on the unmanned boat body. A buffer frame is arranged on the unmanned boat body, and the recovery rope height adjustment component and the recovery rope retracting component are arranged on both sides of the buffer frame.

[0011] The recovery rope height adjustment assembly includes a support rod, and the belt and the adjustment drive motor are both arranged on the support rod, wherein pulleys are provided at the upper and lower ends of the support rod, and the two ends of the belt are respectively passed around the pulleys at the corresponding ends, and the pulleys at either end are driven to rotate by the adjustment drive motor.

[0012] The recovery rope steering assembly includes a first guide element, a tension sensor, a first tensioning clamp, a second tensioning clamp and a second guide element. The recovery rope is guided input via the first guide element, bypasses the tension sensor, passes between the first tensioning clamp and the second tensioning clamp, and is guided output via the second guide element.

[0013] The recovery rope steering assembly is provided with a spring shaft and a spring, and the spring shaft passes through the first tensioning clamp and the second tensioning clamp, and the spring shaft is provided with a spring and a spring pressure plate at one end close to the first tensioning clamp, and one end of the spring is against the spring pressure plate, and the other end is against the first tensioning clamp.

[0014] The recovery rope retracting assembly includes a mounting frame, and the winding wheel and the retracting drive motor are both arranged on the mounting frame, a guide ring is provided at the upper end of the mounting frame, the recovery rope passes through the guide ring and is wound around the winding wheel, a wire buckle is provided on the winding wheel, and a baffle is provided on the side of the winding wheel away from the retracting drive motor.

[0015] According to the control method of the arresting hook test system for the offshore recovery of fixed-wing UAVs, the adjusting driving motor controls the rotation speed through the anti-roll control module, comprising the following steps:

[0016] Step 1: First perform fast Fourier transform on the disturbance, specifically:

[0017] f Obs，i =f FFT，i

[0018]

[0019]

[0020] In the above formula, f FFT，i It means that the peak detector identifies the frequency corresponding to the i-th harmonic in the main N harmonic functions; represents the estimated value after Fourier transformation at time t, represents the estimated value of the first-order derivative after Fourier transform at time t; f Obs，i represents the predicted frequency, represents the predicted phase angle, T represents the time value within a cycle ΔT, a Obs，i represents the predicted amplitude;

[0021] Step 2: Superimpose the estimated harmonics of different frequencies to predict T pre The wave signal after time is as follows:

[0022]

[0023] In the above formula, the compensation value ρ(t) is a constant at time t, which can be calculated as:

[0024] represents the estimated value of the odd wave at time T;

[0025] Step 3: Construct a fuzzy control algorithm for anti-roll, specifically:

[0026] U(t)=K P E(t)+K I ∑E(t)+K D EC(t) (t=0, 1, 2, ...);

[0027] In the above formula, U(t) represents the output value of the PID regulator, that is, the speed of the regulating drive motor (301); E(t) represents the deviation between the desired altitude and the actual altitude of the slider (302) at the current time t; EC(t) is generated by E(t) and represents the rate of change of E(t), and the parameter K P , K I , K D Represents the fuzzy control parameters.

[0028] According to the control method of the arresting hook test system for the offshore recovery of fixed-wing UAVs, the retracting and extending driving motor controls the speed through the flexible variable damping control module, comprising the following steps:

[0029] Step 1: According to the stiffness definition of the motor driver, the stiffness of the recovery rope retracting assembly (8) is expressed as:

[0030]

[0031] Among them, θ l is the output angle of the winding wheel (802), and τ represents the tension of the recovery rope (5).

[0032] Step 2: Calculate the equivalent stiffness;

[0033]

[0034] Among them, θ w is the output angle of the motor reducer, is the input angle of the motor reducer, K represents the stiffness of the motor coil spring;

[0035] Step 3: Choose θ reasonably w and θ l The relationship between the two is K a Make adjustments.

[0036] The advantages and positive effects of the present invention are:

[0037] The present invention takes into account the adverse conditions during recovery at sea, gives full play to the advantages of shipborne equipment, and effectively improves the safety and autonomy of fixed-wing UAV landing in limited deck space. The recovery rope height adjustment component of the present invention controls and adjusts the speed of the drive motor through an adaptive anti-roll control module, which can not only make the slider perform compensatory movement according to water surface conditions such as waves to ensure the level of the recovery rope, but also reduce the error caused by the time lag phenomenon generated by sensors, controllers and other equipment, thereby improving the adaptability of the present invention in different sea areas. The recovery rope retraction and release component of the present invention controls the speed of the retraction and release drive motor through a flexible variable damping control module, so that the recovery rope always maintains a constant tension during the recovery process, ensuring accurate recovery of the UAV and allowing the UAV to land without damage. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] Figure 1 It is a structural schematic diagram of the mechanism of the present invention,

[0039] Figure 2 for Figure 1 Schematic diagram of the recovery rope height adjustment component structure,

[0040] Figure 3 for Figure 1 Schematic diagram of the recovery rope steering assembly structure,

[0041] Figure 4 for Figure 1 Schematic diagram of the recovery rope retracting and releasing component structure,

[0042] Figure 5 This is a schematic diagram of the arresting hook structure on the drone.

[0043] Figure 6 This is a control principle diagram of the anti-roll control module of the present invention.

[0044] Among them, 1 is an arresting hook, 101 is a steering gear, 2 is an unmanned hull, 3 is a recovery rope height adjustment assembly, 301 is an adjustment drive motor, 302 is a slider, 303 is a belt, 304 is a support rod, 4 is a buffer frame, 401 is a buffer pad, 402 is a side baffle, 5 is a recovery rope, 6 is a recovery rope steering assembly, 601 is a first guide element, 602 is a second tensioning clamp, 603 is a tension sensor, 604 is a spring, 605 is a first tensioning clamp, 606 is a second guide element, 607 is a spring shaft, 7 is a mounting support plate, 8 is a recovery rope retracting assembly, 801 is a mounting frame, 8011 is a base frame, 8012 is a stand, 8013 is a guide frame, 802 is a winding wheel, 803 is a wire buckle, 804 is a baffle, 805 is a retracting drive motor, and 806 is a guide ring. DETAILED DESCRIPTION

[0045] The present invention will be further described below in conjunction with the accompanying drawings.

[0046] like Figures 1 to 5As shown, the mechanism of the present invention includes a buffer frame 4, a recovery rope 5, a recovery rope height adjustment component 3, a recovery rope steering component 6 and a recovery rope retracting component 8, wherein the buffer frame 4, the recovery rope height adjustment component 3 and the recovery rope retracting component 8 are all arranged on the unmanned hull 2, and the recovery rope height adjustment component 3 and the recovery rope retracting component 8 are arranged on both sides of the buffer frame 4, and the unmanned hull 2 ​​is provided with a mounting support plate 7 on both sides to support the recovery rope height adjustment component 3 and the recovery rope retracting component 8 on the corresponding side, the recovery rope height adjustment component 3 is provided with a liftable slider 302, and the recovery rope steering component 6 is provided on the slider 302, and the two ends of the recovery rope 5 are respectively passed around the recovery rope steering component 6 on the corresponding side and then wound in the recovery rope retracting component 8 on the corresponding side, as shown in FIG. Figure 2 As shown, the recovery rope height adjustment component 3 includes a belt 303, an adjustment drive motor 301 and a roll reduction control module. The belt 303 is driven to move by the adjustment drive motor 301. The slider 302 is fixedly connected to one side of the belt 303. The adjustment drive motor 301 is controlled to rotate by the roll reduction control module, so that the slider 302 can perform compensation movement according to the set compensation program according to the water surface conditions such as waves, so that the recovery rope 5 can always maintain a horizontal and soft state. The recovery rope retracting component 8 includes a winding wheel 802, a retracting drive motor 805 and a flexible variable damping control module. The recovery rope 5 is wound on the winding wheel 802, and the winding wheel 802 is driven to rotate by the retracting drive motor 805, and the retracting drive motor 805 is controlled to rotate by the flexible variable damping control module, so that the recovery rope 5 maintains tension during the compensation movement of the slider 302.

[0047] like Figure 2 As shown, the recovery rope height adjustment component 3 includes a support rod 304, and the belt 303 and the adjustment drive motor 301 are both arranged on the support rod 304, wherein the support rod 304 is provided with pulleys at both ends, and the two ends of the belt 303 are respectively passed around the pulleys at the corresponding ends, and the pulley at either end is driven to rotate by the adjustment drive motor 301, thereby realizing the movement of the belt 303.

[0048] like Figure 3As shown, the recovery rope steering assembly 6 includes a base and a first guide element 601, a tension sensor 603, a first tensioning clamp 605, a second tensioning clamp 602, a spring shaft 607, a spring 604, and a second guide element 606 arranged on the base, wherein the recovery rope 5 is guided by the first guide element 601 to enter between the first tensioning clamp 605 and the second tensioning clamp 602 after bypassing the tension sensor 603, the spring shaft 607 passes through the first tensioning clamp 605 and the second tensioning clamp 602, and the spring shaft 607 is provided with a spring 604 and a spring pressure plate at one end close to the first tensioning clamp 605 , and the other end passes through the stopper block provided on the base and is threadedly connected with a nut. One end of the spring 604 abuts against the spring pressure plate, and the other end abuts against the first tensioning clamping plate 605. The spring 604 provides elastic force to make the first tensioning clamping plate 605 and the second tensioning clamping plate 602 cooperate to clamp the recovery rope 5 to achieve pre-tightening. By screwing the spring shaft 607, the spring shaft 607 can move and adjust the compression amount of the spring 604, that is, adjust the pre-tightening force of the two tensioning clamping plates. The recovery rope 5 is output between the first tensioning clamping plate 605 and the second tensioning clamping plate 602 and then guided and output through the second guide element 606. The base is mounted on the slider 302 of the recovery rope height adjustment assembly 3 on the corresponding side. In addition, in this embodiment, the first guide element 601 and the second guide element 606 can adopt structures such as guide copper sheets, which is a well-known technology in the art.

[0049] like Figure 4 As shown, the recovery rope retracting assembly 8 includes a mounting frame 801, and a winding wheel 802 and a retracting drive motor 805 are both arranged on the mounting frame 801, a guide ring 806 is provided at the upper end of the mounting frame 801, the recovery rope 5 passes through the guide ring 806 and is wound around the winding wheel 802, a wire buckle 803 is provided on the winding wheel 802 for fixing the end of the recovery rope 5, and a baffle 804 is provided on the side of the winding wheel 802 away from the retracting drive motor 805 to prevent the recovery rope 5 from escaping.

[0050] like Figure 4 As shown, in this embodiment, the mounting frame 801 includes a base frame 8011, a vertical frame 8012 and a guide frame 8013, wherein the vertical frame 8012 is vertically arranged on the base frame 8011, a guide frame 8013 is arranged on the upper end of the vertical frame 8012, the winding wheel 802 and the retracting and extending driving motor 805 are both installed on the vertical frame 8012, and the guide ring 806 is installed on the guide frame 8013.

[0051] like Figure 1 As shown, a buffer pad 401 made of sponge is disposed on the buffer frame 4, and side guards 402 are disposed on both sides of the buffer frame 4, so that the drone can land on the buffer pad 401 to avoid damage.

[0052] like Figure 5 As shown, the lower side of the UAV is provided with an arresting hook 1 which is hooked with the recovery rope 5 to realize recovery, and the lower side of the UAV is provided with a steering gear 2011, and the arresting hook 201 is driven by the steering gear 2011 to rotate and adjust the angle so that it can be hooked on the recovery rope 5. The steering gear 2011 is a well-known technology in the art and is a commercially available product.

[0053] The working principle of the present invention is:

[0054] When the mechanism of the present invention is working, the two ends of the recovery rope 5 are respectively wound around the recovery rope steering assembly 6 on the corresponding side and then wound on the winding wheel 802 of the recovery rope retracting assembly 8 on the corresponding side, and the winding wheel 802 is driven to rotate by the retracting drive motor 805 to realize the retracting and releasing of the recovery rope 5, thereby realizing the tensioning or loosening of the recovery rope 5. The recovery rope steering assembly 6 is arranged on the slider 302 on the recovery rope height assembly 3 on the corresponding side, and the height is adjusted by the slider 302, and the adjustment drive motor 301 is controlled to rotate by the anti-roll control module, thereby enabling the slider 302 to perform compensation movement according to the set compensation program according to the water surface conditions such as sea waves, so that the recovery rope 5 can always maintain a horizontal and soft state, and the recovery rope retracting assembly 8 is provided with a flexible variable damping control module to control the rotation of the retracting drive motor 805, so that the recovery rope 5 always maintains tension during the compensation movement of the slider 302. In addition, the tension sensor 603 on the recovery rope steering assembly 6 guides the recovery rope 5 to turn and also monitors the tension of the recovery rope 5 in real time.

[0055] In one embodiment of the present invention, the regulating drive motor 301 and its driver adopt the EtherCat / IP bus control protocol, the motor adopts a 400W DC servo motor, the rated speed of the motor is 3000RPM, the maximum speed is 6000RPM, and there is no brake. The driver controller adopts an Omron 4-axis motion control unit, and the cycle is set to 20ms.

[0056] The method of controlling by using the anti-roll control module of the present invention is as follows: Figure 6 As shown, the specific steps include:

[0057] Step 1: Perform fast Fourier transform on the disturbance, specifically:

[0058] f Obs，i =f FFT，i

[0059]

[0060]

[0061] In the above formula, f FFT，iIt means that the peak detector identifies the frequency corresponding to the i-th harmonic in the main N harmonic functions; represents the estimated value after Fourier transformation at time t, represents the estimated value of the first-order derivative after the wide-time Fourier transform; f Obs，i represents the predicted frequency, represents the predicted phase angle, T represents the time value within a cycle ΔT, a Obs，i represents the predicted amplitude;

[0062] Step 2: Superimpose the estimated harmonics of different frequencies to predict T pre The wave signal after time is as follows:

[0063]

[0064] In the above formula, the compensation value ρ(t) is a constant at time t, which can be calculated as:

[0065] represents the estimated value of the odd wave at time T;

[0066] Step 3: Construct a fuzzy control algorithm for anti-roll, specifically:

[0067] U(t)=K P E(t)+K I ∑E(t)+K D EC(t) (t=0, 1, 2, ...);

[0068] In the above formula, U(t) represents the output value of the PID regulator, that is, the speed of the drive motor 301 is adjusted; E(t) represents the deviation between the desired altitude and the actual altitude of the slider 302 at the current time t; EC(t) is generated by E(t) and represents the rate of change of E(t), and the parameter K P , K I , K D Indicates the fuzzy control parameters. In addition, the peak detector and Kalman state estimator are both built-in devices of the motor.

[0069] In one embodiment of the present invention, the retracting and releasing driving motor 805 is implemented by a planar scroll spring having an Archimedean spiral and used for TSEA (thin series elastic actuator), and the recovery rope 5 is a low-bending-moment flexible Kevlar rope used to capture the arresting hook 1 on the belly of the fixed-wing UAV. The method of controlling the flexible variable damping control module of the present invention is as follows:

[0070] The steps include:

[0071] Step 1: According to the stiffness definition of the motor driver, the stiffness of the recovery rope retracting assembly 8 can be expressed as:

[0072]

[0073] Among them, θ l is the output angle of the winding wheel 802, and τ represents the tension of the recovery rope 5.

[0074] Step 2: Calculate the equivalent stiffness;

[0075]

[0076] Among them, θ w is the output angle of the motor reducer, is the input angle of the motor reducer, K represents the stiffness of the motor coil spring;

[0077] Step 3: By choosing θ w and θ l The relationship between the two can be used to adjust the functional stiffness of the recovery rope retracting assembly 8 accordingly, thereby achieving the stiffness K a Real-time adjustment ensures the recovery rope has 5 tensions.

Claims

1. An arresting mechanism for recovering fixed-wing UAVs at sea, characterized by: The invention comprises a recovery rope (5), a recovery rope height adjustment component (3), a recovery rope steering component (6) and a recovery rope retracting component (8), wherein the recovery rope height adjustment component (3) is provided with a slider (302), and the slider (302) is provided with a recovery rope steering component (6), and the two ends of the recovery rope (5) are respectively passed around the recovery rope steering component (6) on the corresponding side and then wound into the recovery rope retracting component (8) on the corresponding side; the recovery rope height adjustment component (3) comprises a belt (303), an adjustment drive motor (301) and a sway reduction control module, and the belt (303) passes through the The adjusting drive motor (301) drives the movement, and the adjusting drive motor (301) controls the rotation speed through the anti-roll control module, and the slider (302) is fixedly connected to one side of the belt (303); the recovery rope retracting assembly (8) comprises a winding wheel (802), a retracting drive motor (805) and a flexible variable damping control module, the recovery rope (5) is wound on the winding wheel (802), and the winding wheel (802) is driven to rotate through the retracting drive motor (805), and the retracting drive motor (805) controls the rotation speed through the flexible variable damping control module; The recovery rope steering assembly (6) comprises a first guide element (601), a tension sensor (603), a first tensioning clamp (605), a second tensioning clamp (602) and a second guide element (606); the recovery rope (5) is guided to input via the first guide element (601), bypasses the tension sensor (603), passes between the first tensioning clamp (605) and the second tensioning clamp (602), and is guided to output via the second guide element (606); The recovery rope steering assembly (6) is provided with a spring shaft (607) and a spring (604), and the spring shaft (607) passes through the first tensioning clamp (605) and the second tensioning clamp (602), and the spring shaft (607) is provided with a spring (604) and a spring pressure plate at one end close to the first tensioning clamp (605), and one end of the spring (604) is against the spring pressure plate, and the other end is against the first tensioning clamp (605).

2. The arresting mechanism for recovering fixed-wing UAV at sea according to claim 1 is characterized by: The recovery rope height adjustment component (3) and the recovery rope retracting component (8) are both arranged on the unmanned boat body (2); a buffer frame (4) is arranged on the unmanned boat body (2); and the recovery rope height adjustment component (3) and the recovery rope retracting component (8) are arranged on both sides of the buffer frame (4).

3. The arresting mechanism for recovering fixed-wing UAV at sea according to claim 1 is characterized by: The recovery rope height adjustment assembly (3) comprises a support rod (304), and the belt (303) and the adjustment drive motor (301) are both arranged on the support rod (304), wherein pulleys are arranged at both ends of the support rod (304), and both ends of the belt (303) are respectively passed around the pulleys at the corresponding ends, and the pulley at either end is driven to rotate by the adjustment drive motor (301).

4. The arresting mechanism for recovering fixed-wing UAV at sea according to claim 1 is characterized in that: The recovery rope retracting assembly (8) comprises a mounting frame (801), and a winding wheel (802) and a retracting drive motor (805) are both arranged on the mounting frame (801), a guide ring (806) is arranged at the upper end of the mounting frame (801), the recovery rope (5) passes through the guide ring (806) and is then wound around the winding wheel (802), a wire buckle (803) is arranged on the winding wheel (802), and a baffle (804) is arranged on the side of the winding wheel (802) away from the retracting drive motor (805).

5. A control method for an arresting mechanism for recovering a fixed-wing UAV at sea according to claim 1, characterized in that: The adjusting driving motor (301) controls the rotation speed through the anti-roll control module, comprising the following steps: Step 1: First perform fast Fourier transform on the disturbance, specifically: f Obs，i =f FFT，i In the above formula, f FFT，i It means that the peak detector identifies the frequency corresponding to the i-th harmonic in the main N harmonic functions; represents the estimated value after Fourier transformation at time t, represents the estimated value of the first-order derivative after Fourier transform at time t; f Obs，i represents the predicted frequency, represents the predicted phase angle, T represents the time value within a cycle ΔT, a Obs，i represents the predicted amplitude; Step 2: Superimpose the estimated harmonics of different frequencies to predict T pre The wave signal after time is as follows: In the above formula, the compensation value ρ(t) is a constant at time t, which can be calculated as: represents the estimated value of the odd wave at time T; Step 3: Construct a fuzzy control algorithm for anti-roll, specifically: U(t)=K P E(t)+K I ∑E(t)+K D EC(t)(t=0,1,2,...); In the above formula, U(t) represents the output value of the PID regulator, that is, the speed of the regulating drive motor (301); E(t) represents the deviation between the desired altitude and the actual altitude of the slider (302) at the current time t; EC(t) is generated by E(t) and represents the rate of change of E(t), and the parameter K P , K I , K D Represents the fuzzy control parameters.

6. A control method for an arresting mechanism for recovering a fixed-wing UAV at sea according to claim 1, characterized in that: The retractable drive motor (805) controls the rotation speed through the flexible variable damping control module, comprising the following steps: Step 1: According to the stiffness definition of the motor driver, the stiffness of the recovery rope retracting assembly (8) is expressed as: Among them, θ l is the output angle of the winding wheel (802), and τ represents the tension of the recovery rope (5). Step 2: Calculate the equivalent stiffness; Among them, θ w is the output angle of the motor reducer, is the input angle of the motor reducer, K represents the stiffness of the motor coil spring; Step 3: Choose θ reasonably w and θ l The relationship between the two is K a Make adjustments.

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