A transmedium-wave water-skimming device for aircraft

Abstract

This invention discloses a water-striking ski-jump device for a cross-medium aircraft. Integrated into the aircraft's belly, when the aircraft descends to a preset relative sea surface altitude range, the controller drives the device from a closed state to an extended state based on the relative altitude signal and sea surface state information. This allows the ski-jump board to make brief, controllable contact with the sea surface, generating vertical correction force and attitude correction torque through a "water-striking-rebound-skip" trajectory transition, returning the flight trajectory to the predetermined near-shore low-altitude range. The ski-jump board can actively adjust its deployment timing, position along the fuselage axis, extension distance, retraction / extension state, and water-striking angle of attack according to changes in flight status and sea conditions, achieving coordinated control of the water-striking process and the ski-jump trajectory. After the ski-jump, the device automatically retracts, and the ski-jump board closes to cover the opening of the belly cavity. This device has a compact structure, is easy to integrate into the belly, has minimal impact on the aircraft's shape, and has good engineering application value.

Description

Technical Field

[0001] This invention relates to the field of close-range sea-surface flight technology for cross-medium aircraft, specifically to a water-skimming device for cross-medium aircraft. Background Technology

[0002] Transmedium-based aircraft have broad application prospects in military and civilian fields such as ocean observation, near-surface target detection, emergency search and rescue, and special missions. For this type of aircraft, typical mission requirements are: after approaching the target sea area at a relatively high altitude during the mid-course phase, the aircraft must rapidly reduce its altitude in a short period during the terminal phase, maintaining a stable altitude relative to the sea surface within a predetermined low range, such as several meters to over ten meters above the sea surface, to meet requirements for observation resolution, data consistency, and flight safety margin. If the terminal flight altitude is too high, it will reduce the effectiveness of close-range observation and data acquisition; if the flight altitude is too low, it will increase the risk of water contact, easily causing sudden changes in stress and attitude disturbances, thus affecting flight stability. Therefore, how to achieve rapid correction and stable maintenance of the aircraft's terminal altitude under complex sea conditions is a key problem that needs to be solved during the low-altitude near-shore flight of transmedium-based aircraft.

[0003] However, the significant uncertainties and time-varying nature of the sea surface environment make altitude control during the terminal phase of sea-skimming flight for cross-medium aircraft extremely difficult. On one hand, during descent, the aircraft is affected by aerodynamic disturbances, propulsion system fluctuations, and attitude-track coupling, causing its descent velocity, pitch attitude, and vertical motion to deviate from expectations, resulting in a discrete terminal altitude distribution and difficulty in stable convergence. On the other hand, wave fluctuations, wave direction changes, and local sea state disturbances cause continuous fluctuations in the sea surface reference altitude. Simultaneously, sea surface reflections and clutter interference reduce the stability of altimetry and sea surface identification, leading to errors in relative sea surface altitude estimation. The combined effect of these factors makes it difficult for the aircraft to simultaneously achieve rapid altitude descent and stable maintenance within a limited timeframe, thus affecting the stability and repeatability of the terminal phase sea-skimming flight.

[0004] Current methods for terminal altitude correction and maintenance of cross-medium aircraft typically rely on flight control systems using aerodynamic control surfaces and dynamic adjustment. However, when sea conditions are complex, waves are large, or altimeter errors are significant, relying solely on airborne control methods is easily limited by control margin, response performance, and trajectory correction capabilities, making it difficult to ensure the aircraft stably enters and maintains itself within the target's low altitude zone. Furthermore, many existing surface contact assist systems are passive, and the timing of contact component deployment, contact attitude, water entry depth, and force application are often difficult to actively adjust according to flight status and sea state changes. This results in limited adaptability to complex sea conditions and hinders the achievement of stable, effective, and repeatable trajectory correction.

[0005] In particular, existing auxiliary contact structures typically lack the ability to coordinate and adjust the position of the contact components along the fuselage axis, the extension distance relative to the fuselage belly, the retraction state, and the water-striking angle. This makes it difficult to actively control the water-striking contact process based on real-time altitude, flight attitude, descent speed, and sea surface conditions. Therefore, it is necessary to provide a water-striking ski-jump device capable of actively adjusting the ski-jump position, extension distance, and water-striking angle based on flight status and sea state information, in order to improve the trajectory correction capability of cross-medium aircraft in complex sea conditions and its low-altitude flight stability near the coast. Summary of the Invention

[0006] In view of this, the present invention provides a water-skipping device for a cross-medium aircraft, which has controllable adjustment capabilities. When the aircraft descends to a preset altitude range above the sea surface during the terminal phase, the controller outputs a deployment command based on the relative sea surface altitude signal and sea surface state information, switching the ski-jump device from a closed state to an deployed state. The controller also adjusts the position of the ski-jump board along the fuselage axis, its extension distance, retraction / extension state, and water-striking angle based on flight status and sea state information, ensuring a short-term, controllable contact with the sea surface. The hydrodynamic force generated by the ski-jump board's contact with the water creates an upward vertical force on the aircraft, simultaneously providing attitude correction torque, enabling the aircraft to complete the "water-striking-bounce-skip" trajectory transition, thereby quickly returning to the predetermined near-shore low-altitude range. After the ski-jump, the device is automatically retrieved, the ski-jump board closes to cover the opening of the aircraft's underside cavity, and the flight control system continues attitude stabilization and altitude maintenance, allowing the aircraft to continue flying at a low altitude close to the sea. Compared to relying solely on air control for terminal altitude reduction and maintenance, this method utilizes short-duration, controllable water contact to provide the aircraft with additional trajectory correction capabilities. In particular, it enhances adaptability to complex sea conditions by actively adjusting the axial position, extension distance, and water-striking angle of the skid, thereby reducing the impact of wave fluctuations and altimetry errors on terminal altitude control. Furthermore, it improves the stability and reliability of sea-skimming flight even under conditions of limited control margin.

[0007] The water-skipping device for a cross-medium aircraft of the present invention includes: a slide rail, an electric sliding seat, a main load-bearing hydraulic column, a retraction and extension hydraulic cylinder, an angle-of-attack adjustment hydraulic cylinder, a skid plate, an angle-of-attack sensor, a sea surface detection device, a support seat, and a hydraulic cylinder connecting hinge seat. The hydraulic cylinder connecting hinge seat is installed on the skid plate and includes a front load-bearing hinge seat and a rear angle-adjusting hinge seat.

[0008] The bottom of the transmedium aircraft's belly is provided with a cavity and an opening communicating with the cavity. The skid is located at the opening, and its outer contour is adapted to the shape of the transmedium aircraft's belly. The slide rail is fixedly installed inside the belly of the transmedium aircraft along the fuselage axis. The electric sliding hinge seat is slidably engaged with the slide rail and can reciprocate linearly along the slide rail; The electric sliding hinge includes a slide, a bearing seat, and a translation drive motor. The translation drive motor is connected to the slide and is used to drive the slide to move along the slide rail. The bearing seat is disposed on the slide and moves synchronously with the slide. The upper end of the main load-bearing hydraulic column is movably connected to the bearing seat of the electric sliding seat via a rotating shaft, so that the main load-bearing hydraulic column can rotate relative to the bearing seat around the rotating shaft. The lower end is hinged to the skid plate via a front load-bearing hinge seat. The main load-bearing hydraulic column can extend and retract along its axial direction to adjust the extension distance of the skid plate relative to the belly of the transmedium aircraft. One end of the retraction hydraulic cylinder is connected to the inner wall of the belly of the cross-medium aircraft via a support seat, and the other end is hinged to the main load-bearing hydraulic column. It is used to drive the main load-bearing hydraulic column to swing around the rotation axis of the electric sliding seat so that the skid plate can switch between the closed state and the deployed state. One end of the angle-of-attack adjusting hydraulic cylinder is hinged to the main load-bearing hydraulic column, and the other end is hinged to the rear angle-adjusting hinge seat. It is used to drive the skid plate to rotate relative to the main load-bearing hydraulic column in order to adjust the water-striking angle of the skid plate. The angle of attack sensor is mounted on the skid plate and is used to detect the angle of the skid plate relative to the aircraft axis and output an angle signal for determining the angle of attack when hitting the water. The sea surface detection device is installed at the nose of the transmedium vehicle and is used to detect the relative altitude of the vehicle to the sea surface and the sea surface condition information. The hydraulic cylinder connecting hinge includes a front load-bearing hinge and a rear angle-adjusting hinge disposed on the sliding plate. The front load-bearing hinge is used to form a load-bearing hinge with the main load-bearing hydraulic column, and the rear angle-adjusting hinge is used to form an angle-adjusting hinge with the angle-of-attack adjusting hydraulic cylinder.

[0009] Preferably, the inner side of the skid plate is an arc surface, and the cross-section taken laterally along the body has a circular arc profile, the circular arc profile having a central angle. θ and radius R The central angle θ and radius R The dimensions of the cavity, the installation position of the hydraulic drive mechanism, and the range of motion of the skid plate are determined accordingly.

[0010] Preferably, the main load-bearing hydraulic column includes an airfoil-shaped load-bearing column and a hydraulic telescopic actuator disposed inside the airfoil-shaped load-bearing column. The airfoil-shaped load-bearing column has an airfoil-shaped cross-section and a leading edge and a trailing edge arranged along the direction of the airflow.

[0011] Preferably, the skid plate is provided with a front load-bearing hinge and a rear angle-adjusting hinge. The rotational connections between the front load-bearing hinge and the main load-bearing hydraulic column, between the rear angle-adjusting hinge and the angle-of-attack adjustment hydraulic cylinder, and between the retraction hydraulic cylinder and the support base and the main load-bearing hydraulic column are all made of hinged connection components. The hinged connection components include connecting lugs and pins. The pins pass through the connecting lugs to form a rotational connection.

[0012] Preferably, the main load-bearing hydraulic column, the retraction hydraulic cylinder, and the angle-of-attack adjustment hydraulic cylinder are all hydraulic actuators.

[0013] Preferably, the hydraulic circuits corresponding to the main load-bearing hydraulic column, the retraction hydraulic cylinder, and the angle-of-attack adjustment hydraulic cylinder are all equipped with throttling buffer units and overload protection units. The throttling buffer unit is used to provide hydraulic damping to reduce sudden speed changes under impact or rapid action conditions; the overload protection unit is used to relieve pressure when the pressure exceeds a set threshold to limit peak pressure.

[0014] Preferably, the throttling buffer unit includes a one-way throttling valve and a buffer valve; the overload protection unit includes an overflow valve and a balancing valve.

[0015] Preferably, the damping parameters, pressure threshold, and actuation rate of the hydraulic circuit are set or switched according to the flight status of the transmedium aircraft and the sea state level.

[0016] Preferably, the sea surface state information includes wave undulation information, wave direction information, wave height change information, and local sea surface disturbance information.

[0017] The present invention also provides a method for a cross-medium aircraft to perform a water-skipping maneuver based on the above-mentioned device, comprising the following steps: a) The sea surface detection device 8 monitors the relative altitude between the transmedium aircraft and the sea surface in real time, as well as the sea surface condition, and outputs the relative altitude signal between the transmedium aircraft and the sea surface and the sea surface condition information. b) When the relative height between the transmedium aircraft and the sea surface meets the preset start conditions, the controller outputs a start command: the electric sliding hinge (2) moves along the slide rail (1) to the predetermined position to adjust the position of the skid plate 6 along the fuselage axis; c) Control the action of the retractable hydraulic cylinder (4) to make the main load-bearing hydraulic column (3) swing around the rotating axis to realize the unfolding of the device and switch the sliding plate (6) from the closed state to the unfolded state; d) Control the extension and retraction of the main load-bearing hydraulic column (3) to adjust the extension distance of the skid plate (6) relative to the belly of the transmedium aircraft; e) Control the action of the angle of attack adjustment hydraulic cylinder (5) to adjust the angle of rotation of the sliding board (6) relative to the main load-bearing hydraulic column (3) so that the sliding board (6) is adjusted to the target water-striking angle; f) Obtain the angle signal output by the angle of attack sensor (7), and combine it with the relative height signal and sea surface state information to dynamically adjust the position, extension distance, retraction state and water attack angle of the skid board (6) along the fuselage axis, so that the skid board (6) remains within the predetermined control range during the skid process; g) After the cross-medium aircraft completes the ski jump, when the relative altitude signal meets the preset recovery conditions, the controller outputs a recovery command, the device is reset, and the ski jump plate (6) is closed to seal the cavity opening.

[0018] Beneficial effects: 1. This invention proposes a water-striking and ski-jumping device for a cross-medium aircraft. The device is integrated into the belly of the aircraft. In the non-operating state, the ski-jumping ramp closes and covers the opening of the belly cavity. In the operating state, the ski-jumping ramp unfolds and makes a short, controllable contact with the sea surface. When the aircraft approaches the target sea area and descends to a preset relative sea surface altitude range, the short, controllable contact between the ski-jumping ramp and the sea surface achieves a "water-striking-rebound-skimping" trajectory transition. Utilizing hydrodynamic impact and fluid reaction, a significant vertical correction effect is generated, allowing the aircraft trajectory to quickly return to the predetermined near-shore low-altitude range. Compared to traditional terminal altitude correction methods, this invention can achieve faster and more direct altitude recovery in a shorter time, improving the problem that traditional methods struggle to simultaneously achieve rapid descent and stable altitude recovery within a short period.

[0019] 2. The ski-jump ramp in this invention has controllable adjustment capabilities. It can actively adjust the timing of deployment, its position along the fuselage axis, its extension distance, its retraction / extension state, and its water-striking angle based on the aircraft's relative sea surface altitude, flight attitude, descent speed, and sea state changes. This makes the contact process between the ski-jump ramp and the sea surface more controllable. Through the above-mentioned multi-parameter coordinated adjustment, the water-striking impact intensity, vertical correction force, and attitude correction effect can be effectively controlled, improving the stability and accuracy of trajectory correction. This is particularly beneficial for enhancing the device's adaptability to complex sea conditions such as large wave fluctuations and significant wave surface changes.

[0020] 3. With the device of this invention, after the aircraft completes the ski-jump and enters the target low-altitude zone, the flight control system takes over and performs attitude stabilization and altitude maintenance. Since the ski-jump process has corrected the aircraft's altitude and attitude to a range closer to the target operating conditions, the control correction required for subsequent sea-skimming flight is smaller, and the flight state is more stable. This is beneficial for maintaining near-shore low-altitude flight over a longer distance and helps reduce altitude drift caused by factors such as wave fluctuations and altimetry fluctuations, thereby improving flight stability, repeatability, and mission execution reliability.

[0021] 4. The device of this invention has a compact structure and can be integrated into the abdominal cavity of a cross-medium aircraft. In the non-operating state, the gliding ramp closes and adapts to the shape of the aircraft's abdomen, with minimal impact on the original aerodynamic layout of the aircraft. At the same time, the overall structure of the device is well-defined, facilitating installation, deployment, and control. It can achieve the water-skiing function while also considering engineering feasibility and integrability, and has good application and promotion value. Attached Figure Description

[0022] Figure 1 This is a schematic diagram of the external appearance of the device of the present invention.

[0023] Figure 2 This is a schematic diagram of the internal structure of the device of the present invention.

[0024] Figure 3 This is a partially enlarged schematic diagram of the internal structure of the device of the present invention.

[0025] Figure 4 This is a schematic diagram of the closed state of the device of the present invention.

[0026] Figure 5 This is a schematic diagram of the device of the present invention in its unfolded state.

[0027] Figure 6 This is a schematic diagram of the water-spraying angle adjustment of the device of the present invention.

[0028] Figure 7 This is a schematic diagram illustrating the axial position adjustment of the device of the present invention along the fuselage.

[0029] Figure 8 This is a schematic diagram of the water-skipping trajectory of a cross-medium aircraft.

[0030] Figure 9 This is a schematic diagram of the transverse cross-section of the skid ramp of a cross-medium aircraft.

[0031] Figure 10 This is a schematic diagram of the cross-section of the main load-bearing hydraulic column of a cross-medium aircraft.

[0032] Among them, 1-slide rail; 2-electric sliding hinge seat; 3-main load-bearing hydraulic column; 4-retracting hydraulic cylinder; 5-angle of attack adjustment hydraulic cylinder; 6-sliding ramp; 7-angle of attack sensor; 8-sea surface detection device; 9-support seat; 10-hydraulic cylinder connecting hinge seat 10; 10a-front load-bearing hinge seat; 10b-rear angle adjustment hinge seat. Detailed Implementation

[0033] The present invention will now be described in detail with reference to the accompanying drawings and embodiments.

[0034] This invention provides a water-skipping device for cross-medium aircraft. Integrated into the belly of the aircraft, the device extends in a controlled manner as the aircraft descends and approaches the sea surface, entering a preset relative sea-surface altitude range. It actively adjusts the position, deployment attitude, angle of attack, and operational process of the skid plate according to flight status and sea conditions, ensuring a short, controllable contact between the skid plate and the sea surface. Utilizing hydrodynamic impact and fluid reaction, it achieves a "water-bounce-skip" trajectory transition, thereby providing a small-angle, rapid, and controlled vertical correction to the aircraft's flight trajectory, allowing the aircraft to return and stabilize more quickly within the predetermined near-shore low-altitude range. After the skid is completed, the device automatically retracts, and the aircraft maintains attitude and altitude stability under the control system, thus improving the stability, repeatability, and adaptability to complex sea conditions during low-altitude flight near the sea surface.

[0035] The device of the present invention mainly includes: a slide rail 1, an electric sliding hinge seat 2, a main load-bearing hydraulic column 3, a retraction hydraulic cylinder 4, an angle-of-attack adjusting hydraulic cylinder 5, a sliding ramp 6, an angle-of-attack sensor 7, a sea surface detection device 8, a support seat 9, and a hydraulic cylinder connecting hinge seat 10; wherein, the hydraulic cylinder connecting hinge seat 10 includes a front load-bearing hinge seat 10a and a rear angle-adjusting hinge seat 10b.

[0036] A rectangular cavity is formed at the bottom of the underside of the transmedium aircraft to house this device. A ski-jump ramp 6 is positioned at the opening of this cavity. The outer contour of the ski-jump ramp 6 conforms to the shape of the transmedium aircraft's underside, while its inner side is an arc-shaped structure. The ski-jump ramp 6 is connected to the main load-bearing hydraulic column 3 and the angle-of-attack adjusting hydraulic cylinder 5, and is housed within the cavity. When the transmedium aircraft is in normal flight, the ski-jump ramp 6 is in a closed state, completely covering the opening of the cavity, and its outer contour remains essentially consistent with the shape of the transmedium aircraft's underside to maintain the streamlined shape of the fuselage and reduce additional drag. The inner side of the ski-jump ramp 6 is arc-shaped, forming an arc-shaped plate structure along any transverse cross-section of the fuselage, where the central angle of the arc is [missing information]. θ , radius is R The central angle θ and radius R The geometry of the inner arc surface of the slide board 6 is defined to ensure that, when the slide board 6 is housed within the cavity, its inner arc surface can avoid the main load-bearing hydraulic column 3, the retraction hydraulic cylinder 4, the angle-of-attack adjustment hydraulic cylinder 5, and the hinged connecting components. This ensures that the closing, unfolding, and angle-of-attack adjustment movements of the slide board 6 do not interfere with the mechanisms within the cavity. When the slide board 6 unfolds and participates in water impact and gliding, its outer working surface contacts the water, and the set angle of attack is used to dissipate the water flow and support the gliding.

[0037] For ease of description, the direction from the nose to the tail of the transmedium aircraft is taken as the fuselage axis, the left and right direction of the fuselage is taken as the transverse direction, and the ventral and dorsal direction of the fuselage is taken as the vertical direction.

[0038] The slide rail 1 is fixedly installed along the fuselage axis on the upper wall of the belly of the transmedium aircraft. The electric sliding hinge 2 is slidably engaged with the slide rail 1 and can reciprocate linearly along the slide rail 1. The electric sliding hinge 2 includes a slide block, a bearing seat, and a translation drive motor. The slide block is slidably connected to the slide rail 1, and the translation drive motor is driven by the slide block to drive the slide block to move along the slide rail 1. The bearing seat is disposed on the slide block and moves synchronously with the slide block. The bearing seat is rotatably connected to a rotating shaft, and the rotating shaft is fixedly connected to the upper end of the main load-bearing hydraulic column 3, so that the main load-bearing hydraulic column 3 can rotate relative to the bearing seat around the rotating shaft. When the translation drive motor drives the slide block to move along the slide rail 1, the bearing seat, rotating shaft, main load-bearing hydraulic column 3, and the skid plate 6 connected to the main load-bearing hydraulic column 3 move synchronously along the fuselage axis with the slide block, thereby realizing the position adjustment of the skid plate 6 along the fuselage axis.

[0039] The main load-bearing hydraulic column 3 is the primary load-bearing component of this device, comprising an airfoil-shaped load-bearing column and a hydraulic telescopic actuator disposed within the airfoil-shaped load-bearing column. The airfoil-shaped load-bearing column has an airfoil-shaped cross-section with leading and trailing edges along the upstream direction to reduce resistance and flow disturbance during deployment, skidding, and recovery of the device in nearshore areas. The hydraulic telescopic actuator is used to realize the load-bearing and telescopic support functions of the main load-bearing hydraulic column 3. The upper end of the main load-bearing hydraulic column 3 is fixedly connected to the rotating shaft on the electric sliding hinge seat 2, and the lower end of the main load-bearing hydraulic column 3 is hinged to the skid plate 6 through the front load-bearing hinge seat 10a. The skid plate 6 is provided with a front load-bearing hinge seat 10a and a rear angle-adjusting hinge seat 10b. The front load-bearing hinge seat 10a is used to form a load-bearing hinge with the main load-bearing hydraulic column 3 and to provide a hinge fulcrum for the rotation of the skid plate 6 relative to the main load-bearing hydraulic column 3. The rear angle-adjusting hinge seat 10b is used to form an angle-adjusting hinge with the angle-of-attack adjusting hydraulic cylinder 5, thereby constituting a controllable angle-adjusting mechanism for the skid plate 6. The main load-bearing hydraulic column 3 adjusts the extension distance of the skid plate 6 relative to the belly of the transmedium aircraft through its own telescopic movement, and transmits the support load during the water impact and skid jump of the skid plate 6. The retraction hydraulic cylinder 4 is used to drive the main load-bearing hydraulic column 3 to swing around the rotating shaft relative to the bearing seat. One end of the cylinder is connected to the inner wall of the transmedium aircraft through the support seat 9, and the other end is hinged to the main load-bearing hydraulic column 3. When the effective length of the retractable hydraulic cylinder 4 changes, it applies a pushing or pulling force to the main load-bearing hydraulic column 3, and generates a driving torque around the rotating shaft as the center of rotation, causing the main load-bearing hydraulic column 3 to swing relative to the bearing seat, thereby realizing the retraction, extension, and swing angle adjustment of the main load-bearing hydraulic column 3. During the swinging process of the main load-bearing hydraulic column 3, the sliding plate 6 connected to the main load-bearing hydraulic column 3 moves accordingly, thereby realizing the switching between the closed and extended states of the sliding plate 6.

[0040] The angle-of-attack adjusting hydraulic cylinder 5 is used to adjust the rotation angle of the skid plate 6 relative to the main load-bearing hydraulic column 3, thereby adjusting the water-striking angle of the skid plate 6 relative to the aircraft axis. One end of the angle-of-attack adjusting hydraulic cylinder 5 is hinged to the main load-bearing hydraulic column 3, and the other end is hinged to the rear angle-adjusting hinge seat 10b of the skid plate 6. When the effective length of the angle-of-attack adjusting hydraulic cylinder 5 changes, the angle-of-attack adjusting hydraulic cylinder 5 drives the skid plate 6 to rotate relative to the main load-bearing hydraulic column 3 around the front load-bearing hinge seat 10a, thereby achieving controlled adjustment of the water-striking angle of the skid plate 6. When the effective length of the retraction hydraulic cylinder 4 remains unchanged, the angle-of-attack adjusting hydraulic cylinder 5 can still adjust the rotation angle of the skid plate 6 relative to the main load-bearing hydraulic column 3 by its own extension and retraction; when the retraction hydraulic cylinder 4 drives the main load-bearing hydraulic column 3 to swing, the angle-of-attack adjusting hydraulic cylinder 5 further adjusts the water-striking angle of the skid plate 6 based on the current swing position of the main load-bearing hydraulic column 3.

[0041] As can be seen from the above-mentioned connection relationships of the components, the position of the ski-jump 6 along the fuselage axis is mainly adjusted by the translational movement of the electric sliding hinge 2 along the slide rail 1; the switching between the closed and extended states of the ski-jump 6 is mainly achieved by the swinging of the main load-bearing hydraulic column 3 driven by the retraction and extension hydraulic cylinder 4; the extension distance of the ski-jump 6 relative to the belly of the transmedium aircraft is determined by the extension and retraction of the main load-bearing hydraulic column 3 and the swinging position formed by the retraction and extension hydraulic cylinder 4; the water-striking angle of the ski-jump 6 is adjusted by the angle-of-attack adjustment hydraulic cylinder 5. Thus, the ski-jump 6 can achieve position adjustment, retraction and extension adjustment, extension distance adjustment, and water-striking angle adjustment along the fuselage axis.

[0042] By actively controlling and adjusting the water-striking angle of the skid ramp 6 in real time, the entry attitude, hydrodynamic direction, and vertical support effect of the skid ramp 6 upon contact with the sea surface can be changed, thereby adjusting the water-striking impact intensity, rebound amplitude, and skid trajectory. Especially under conditions of large wave fluctuations, significant changes in wave surface slope, or strong fluctuations in aircraft sinking speed, the water-striking angle of the skid ramp 6 can be adaptively and dynamically adjusted according to real-time operating conditions to enhance the device's adaptability to complex sea conditions and improve the stability of trajectory correction.

[0043] Each rotating connection of the device is provided with a hinge connection assembly, which includes a connecting lug and a pin. The pin passes through the connecting lug to form a rotating connection, thereby ensuring the rotational freedom of each rotating connection and improving the reliability of the mechanism connection.

[0044] Preferably, the main load-bearing hydraulic cylinder 3, the retraction and extension hydraulic cylinder 4, and the angle-of-attack adjusting hydraulic cylinder 5 are all hydraulic actuators, and their respective hydraulic circuits are equipped with throttling buffer units and overload protection units. The throttling buffer unit includes a one-way throttling valve and a buffer valve, used to provide hydraulic damping to reduce sudden speed changes under impact or rapid action conditions. The overload protection unit includes a relief valve and a balance valve, used to relieve pressure when the pressure exceeds a set threshold to limit peak pressure. When the device generates impact loads under short-term controlled water impact or disturbance conditions, each hydraulic circuit can achieve buffer protection through throttling damping and relief pressure relief, thereby reducing peak loads, minimizing the risk of structural damage, and improving the operational reliability of rods, hinged connections, and mounting bases under complex sea state impact conditions. Furthermore, the damping parameters, pressure thresholds, and actuation rates of the hydraulic circuits can be set or switched according to the flight status and sea state level to achieve matched control under different sea states, improving the device's environmental adaptability and operational stability.

[0045] A sea surface detection device 8 is installed on the cross-medium aircraft. This device detects the relative altitude between the aircraft and the sea surface, as well as the sea surface condition information, and sends the corresponding detection signals to the controller. The sea surface condition information includes wave undulation information, wave direction information, wave height change information, and local sea surface disturbance information. Preferably, the aircraft also integrates attitude sensors, angular velocity sensors, and acceleration sensors to acquire flight status information such as pitch attitude, angular velocity, descent speed, and vertical acceleration, and sends the corresponding signals to the controller. The controller is connected to the electric sliding hinge 2, the main load-bearing hydraulic column 3, the retraction and extension hydraulic cylinder 4, and the angle-of-attack adjustment hydraulic cylinder 5. Based on the relative sea surface altitude and sea state information output by the sea surface detection device 8, and the information output by each flight status sensor, the controller comprehensively determines the deployment timing, axial position along the fuselage, extension distance, retraction and extension status, and target water-striking angle of attack of the ski-jump 6, thereby achieving multi-parameter coordinated and controllable adjustment during the ski-jump process and improving the device's adaptability to complex sea conditions.

[0046] When the cross-medium aircraft flies into the sea and enters the terminal altitude adjustment phase, the sea surface detection device 8 detects the aircraft's altitude relative to the sea surface and the sea surface state in real time, and sends the detection signal to the controller. The controller makes a comprehensive judgment on the detection signal and flight status information. When the altitude relative to the sea surface meets the preset start conditions, the controller outputs a start command: drives the electric sliding hinge 2 to move along the slide rail 1 to the predetermined position, and then controls the retraction hydraulic cylinder 4 to drive the main load-bearing hydraulic column 3 to rotate around the pivot to realize the deployment of the device, and controls the angle of attack adjustment hydraulic cylinder 5 to adjust the skid plate 6 to the target water-striking angle of attack, so that the skid device enters the working state. Subsequently, before and during contact with the sea surface, the controller dynamically adjusts the position, extension distance, retraction status, and water-striking angle of the skid board 6 along the fuselage axis based on real-time detected altitude, attitude, sinking speed, and sea state changes. This ensures that the skid board 6 makes short, controllable contact with the sea surface at a preset or real-time corrected extension distance and water-striking angle, obtaining the required vertical correction force and attitude correction torque under controllable impact conditions. This keeps the water-striking process of the skid board 6 within a predetermined control range, improving the stability and repeatability of trajectory correction. After the transmedium aircraft completes the skid, when the relative sea surface height meets the preset recovery conditions, the controller outputs a recovery command, causing the skid device to reset and the skid board 6 to close and cover the cavity opening.

[0047] An angle-of-attack sensor 7 is installed on the ski-jump board 6. The angle-of-attack sensor 7 detects the water-striking angle of the ski-jump board 6 relative to the aircraft axis and outputs an angle signal. The angle-of-attack sensor 7 is electrically connected to the controller. The controller performs closed-loop control of the angle-of-attack adjustment hydraulic cylinder 5 based on the angle signal, adjusting the water-striking angle of the ski-jump board 6 to a preset target angle of attack and maintaining it within the allowable error range during operation. When the angle signal exceeds a preset safety threshold, the controller outputs a limiting, return-to-center, or recovery command to achieve stable control and safety protection of the water-striking angle of the ski-jump board 6. Furthermore, the controller can set different target water-striking angle ranges, angle-of-attack change rate limits, and safety thresholds according to different sea conditions, enabling the ski-jump board 6 to maintain a preset water-striking attitude and ski-jump control effect in calm, moderate, and complex sea conditions.

[0048] Through the above-mentioned structure and control method, the skid 6 in this invention can not only complete the deployment and retrieval and water-striking skid, but also achieve coordinated control of the deployment timing, position along the fuselage axis, extension distance, deployment and retrieval status, water-striking angle of attack, impact process and recovery timing for different flight states and sea conditions. This significantly enhances the trajectory correction capability, attitude stability capability and continuous low-altitude flight capability of cross-medium aircraft under complex sea conditions.

[0049] The present invention also provides a method for a cross-medium aircraft to perform a water-skipping maneuver using the above-described device, comprising: a) Acquire the relative altitude signal between the cross-medium aircraft and the sea surface and the sea surface status information output by the sea surface detection device (8); b) When the relative height signal meets the preset start conditions, the controller outputs a start command to drive the electric sliding hinge (2) to move along the slide rail (1) to the predetermined position; c) Control the action of the retractable hydraulic cylinder (4) to make the main load-bearing hydraulic column (3) rotate around the rotating shaft to realize the unfolding of the device, and adjust the unfolding posture of the sliding plate (6) and switch the sliding plate (6) from the closed state to the unfolded state; d) Control the action of the angle-of-attack adjustment hydraulic cylinder (5) to adjust the angle of rotation of the sliding board (6) relative to the main load-bearing hydraulic column (3) so that the sliding board 6 is adjusted to the target water-striking angle; e) Obtain the angle signal output by the angle of attack sensor (7), and combine it with the relative height signal and sea surface state information to dynamically adjust the position, extension distance, retraction state and water-striking angle of the skid (6) along the fuselage axis, so that the skid (6) remains within the predetermined control range during the skid process; f) After the cross-medium aircraft completes the ski jump, when the relative altitude signal meets the preset recovery conditions, the controller outputs a recovery command to reset the device and close the ski jump plate (6) to seal the cavity opening.

[0050] In step b), the predetermined position is used to correct the axial position of the main load-bearing hydraulic column (3) and the skid plate (6) relative to the cross-medium aircraft. The predetermined position is preset or determined in real time according to the detection signal output by the sea surface detection device (8).

[0051] During steps c) to e), the hydraulic circuits corresponding to the main load-bearing hydraulic column (3), the retraction hydraulic cylinder (4), and the angle-of-attack adjustment hydraulic cylinder (5) are damped by the throttling buffer unit and pressure relief and peak limiting by the overload protection unit to reduce the peak impact load.

[0052] In step e), when the angle signal exceeds the preset safety threshold, or when the sea surface status information indicates that the current sea condition exceeds the preset working range, the controller outputs a limiting, aligning, position correction, or recovery command to achieve stable control and safety protection of the water-bombing angle of the skid (6).

[0053] In summary, the above are merely preferred embodiments of the present invention and are not intended to limit the scope of protection of the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A water-skimming device for a cross-medium aircraft, characterized in that, include: The slide rail 1, electric sliding seat 2, main load-bearing hydraulic column 3, retraction hydraulic cylinder 4, angle of attack adjustment hydraulic cylinder 5, slide board 6, angle of attack sensor 7, sea surface detection device 8, support seat 9 and hydraulic cylinder connecting hinge seat 10, wherein the hydraulic cylinder connecting hinge seat 10 is installed on the slide board 6, including front load-bearing hinge seat 10a and rear angle adjustment hinge seat 10b. The bottom of the transmedium aircraft's belly is provided with a cavity and an opening communicating with the cavity. The skid plate 6 is located at the opening, and its outer contour is adapted to the shape of the transmedium aircraft's belly. The slide rail 1 is fixedly installed inside the belly of the transmedium aircraft along the fuselage axis; The electric sliding hinge 2 is slidably engaged with the slide rail 1 and can reciprocate linearly along the slide rail 1; The electric sliding hinge 2 includes a slide, a bearing seat, and a translation drive motor. The translation drive motor is connected to the slide and is used to drive the slide to move along the slide rail 1. The bearing seat is disposed on the slide and moves synchronously with the slide. The upper end of the main load-bearing hydraulic column 3 is movably connected to the bearing seat of the electric sliding seat 2 via a rotating shaft, so that the main load-bearing hydraulic column 3 can rotate relative to the bearing seat around the rotating shaft. The lower end is hinged to the skid plate 6 via the front load-bearing hinge seat 10a. The main load-bearing hydraulic column 3 can extend and retract along its axial direction to adjust the extension distance of the skid plate 6 relative to the belly of the transmedium aircraft. One end of the retraction hydraulic cylinder 4 is connected to the inner wall of the belly of the cross-medium aircraft through the support seat 9, and the other end is hinged to the main load-bearing hydraulic column 3. It is used to drive the main load-bearing hydraulic column 3 to swing around the rotating axis of the electric sliding seat 2 so that the skid plate 6 can switch between the closed state and the deployed state. One end of the angle-of-attack adjusting hydraulic cylinder 5 is hinged to the main load-bearing hydraulic column 3, and the other end is hinged to the rear angle-adjusting hinge seat 10b. It is used to drive the sliding board 6 to rotate relative to the main load-bearing hydraulic column 3 in order to adjust the water-striking angle of the sliding board 6. The angle of attack sensor 7 is mounted on the skid plate 6 and is used to detect the angle of the skid plate 6 relative to the aircraft axis and output an angle signal for determining the angle of attack when hitting the water. The sea surface detection device 8 is installed at the nose of the transmedium aircraft and is used to detect the relative altitude between the aircraft and the sea surface as well as sea surface condition information. The hydraulic cylinder connecting hinge 10 includes a front load-bearing hinge 10a and a rear angle-adjusting hinge 10b disposed on the sliding plate 6. The front load-bearing hinge 10a is used to form a load-bearing hinge with the main load-bearing hydraulic column 3, and the rear angle-adjusting hinge 10b is used to form an angle-adjusting hinge with the angle-of-attack adjusting hydraulic cylinder 5.

2. The water-skipping device for cross-medium aircraft as described in claim 1, characterized in that, The inner side of the slide board 6 is an arc surface, and the cross-section taken along the transverse direction of the machine body has an arc-shaped profile. The arc-shaped profile has a central angle. θ and radius R The central angle θ and radius R The dimensions of the cavity, the installation position of the hydraulic drive mechanism, and the range of motion of the sliding plate 6 are determined accordingly.

3. The water-skipping device for cross-medium aircraft as described in claim 1, characterized in that, The main load-bearing hydraulic column 3 includes an airfoil load-bearing column and a hydraulic telescopic actuator disposed inside the airfoil load-bearing column. The airfoil load-bearing column has an airfoil structure in cross-section and has a leading edge and a trailing edge along the direction of the airflow.

4. The water-skipping device for cross-medium aircraft as described in claim 1, characterized in that, The sliding board 6 is provided with a front load-bearing hinge seat 10a and a rear angle-adjusting hinge seat 10b. The rotational connections between the front load-bearing hinge seat 10a and the main load-bearing hydraulic column 3, between the rear angle-adjusting hinge seat 10b and the angle-of-attack adjustment hydraulic cylinder 5, and between the retraction hydraulic cylinder 4 and the support seat 9 and the main load-bearing hydraulic column 3 are all made of hinged connection components. The hinged connection components include connecting lugs and pins. The pins are inserted into the connecting lugs to form a rotational connection.

5. The water-skipping device for cross-medium aircraft as described in claim 1, characterized in that, The main load-bearing hydraulic cylinder 3, the retraction hydraulic cylinder 4, and the angle-of-attack adjustment hydraulic cylinder 5 are all hydraulic actuators.

6. The water-skipping device for cross-medium aircraft as described in claim 5, characterized in that, The hydraulic circuits corresponding to the main load-bearing hydraulic cylinder 3, the retraction hydraulic cylinder 4, and the angle-of-attack adjustment hydraulic cylinder 5 are all equipped with throttling buffer units and overload protection units. The throttling buffer unit is used to provide hydraulic damping to reduce speed changes under impact or rapid action conditions; the overload protection unit is used to relieve pressure to limit peak pressure when the pressure exceeds a set threshold.

7. The water-skipping device for cross-medium aircraft as described in claim 6, characterized in that, The throttling buffer unit includes a one-way throttling valve and a buffer valve; the overload protection unit includes an overflow valve and a balancing valve.

8. The water-skipping device for cross-medium aircraft as described in claim 6, characterized in that, The damping parameters, pressure threshold, and actuation rate of the hydraulic circuit are set or switched according to the flight status of the cross-medium aircraft and the sea state level.

9. The water-skipping device for a cross-medium aircraft as described in claim 1, characterized in that, The sea surface state information includes wave undulation information, wave direction information, wave height change information, and local sea surface disturbance information.

10. A method for a cross-medium aircraft to perform a water-skiing glide based on the device described in any one of claims 1 to 9, characterized in that, Includes the following steps: a) The sea surface detection device 8 monitors the relative altitude between the transmedium aircraft and the sea surface in real time, as well as the sea surface condition, and outputs the relative altitude signal between the transmedium aircraft and the sea surface and the sea surface condition information. b) When the relative height between the transmedium aircraft and the sea surface meets the preset start conditions, the controller outputs a start command: the electric sliding hinge (2) moves along the slide rail (1) to the predetermined position to adjust the position of the skid plate 6 along the fuselage axis; c) Control the action of the retractable hydraulic cylinder (4) to make the main load-bearing hydraulic column (3) swing around the rotating axis to realize the unfolding of the device and switch the sliding plate (6) from the closed state to the unfolded state; d) Control the extension and retraction of the main load-bearing hydraulic column (3) to adjust the extension distance of the skid plate (6) relative to the belly of the transmedium aircraft; e) Control the action of the angle of attack adjustment hydraulic cylinder (5) to adjust the angle of rotation of the sliding board (6) relative to the main load-bearing hydraulic column (3) so that the sliding board (6) is adjusted to the target water-striking angle; f) Obtain the angle signal output by the angle of attack sensor (7), and combine it with the relative height signal and sea surface state information to dynamically adjust the position, extension distance, retraction state and water attack angle of the skid board (6) along the fuselage axis, so that the skid board (6) remains within the predetermined control range during the skid process; g) After the cross-medium aircraft completes the ski jump, when the relative altitude signal meets the preset recovery conditions, the controller outputs a recovery command, the device is reset, and the ski jump plate (6) is closed to seal the cavity opening.

Images