Aircraft longitudinal motion simulation method for heave and pitch deck landing

Abstract

The application discloses a kind of aircraft longitudinal motion simulation methods for heave and sway platform landing.First, the geometric configuration of heave and sway platform is determined, and the motion modeling and simulation of heave and sway platform are completed according to the determined geometric configuration;Then, the aircraft landing motion model is added, the position information of the aircraft relative to the heave and sway platform is solved, the landing result is judged according to the position information, and the simulation diagram is generated.For the landing process of the aircraft landing on the platform and flying over the platform, relevant simulation diagrams can be generated respectively.Finally, the above modeling and simulation functions are integrated into a functional module: the module input is the parameters describing the motion of heave and sway platform and the longitudinal motion of aircraft, and the output is the data reflecting the landing result of the aircraft facing heave and sway platform.The method can accurately model the position and attitude of heave and sway platform in real time, calculate the relative position of the aircraft and heave and sway platform, and show the scene of the aircraft landing facing heave and sway platform.

Description

Technical Field

[0001] This invention relates to the field of aircraft landing simulation technology, and in particular to a method for simulating the longitudinal motion of an aircraft landing on a heave-and-sag swaying platform. Background Technology

[0002] Landing technology for aircraft on moving platforms, especially for platforms with uncertain and nonlinear motion characteristics such as ships, offshore drilling platforms, or vehicle-mounted recovery platforms, is one of the key technologies to ensure the safe recovery of aircraft in dynamic environments. Therefore, flight simulators or motion swing platforms are commonly used to simulate application scenarios for aircraft landing on moving platforms, such as carrier-based aircraft landings, spacecraft recovery at sea, and UAV recovery on land-based moving platforms, to verify and evaluate relevant control methods.

[0003] Considering that actual flight tests or semi-physical simulation experiments are often costly or risky, they are generally only conducted after the control method has been verified by computer simulation and its feasibility has been basically determined. Accurate simulation of the aircraft landing process is of significant practical engineering importance for verifying the aircraft's flight quality, flight control algorithm performance, and the reliability of the aircraft landing guidance system. Although domestic research on recovering aircraft on motion platforms has been conducted for some time, most of it focuses on motion platform structural design, drive control methods, motion prediction methods, aircraft landing control law design, and anti-interference and fault-tolerant control algorithm design, with few reports on system simulation methods.

[0004] In view of this, the present invention is hereby proposed. Summary of the Invention

[0005] The purpose of this invention is to provide a simulation method for the longitudinal motion of an aircraft landing on a heave ramp, thereby solving the aforementioned technical problems in the prior art. The method described in this invention can accurately model the position and attitude of the heave ramp in real time, calculate the relative position of the aircraft and the heave ramp, demonstrate the scenario of the aircraft landing on the heave ramp, and accurately calculate the landing point information.

[0006] The objective of this invention is achieved through the following technical solution: A method for simulating the longitudinal motion of an aircraft landing on a heave-and-sway platform, the method comprising: Step 1: Determine the geometric configuration of the heave platform. In a two-dimensional plane, model the heave platform as a straight line segment whose length does not change with the movement of the platform. Model the support below the heave platform as an isosceles triangle, with the vertex of the isosceles triangle coinciding with the midpoint of the straight line segment. Step 2: Based on Step 1, calculate the spatial positions of the platform center and both ends according to the lifting height of the midpoint of the heave platform and the tilt angle of the heave platform relative to the horizontal plane. Then, combined with the positions of the two ends of the bottom edge of the support, complete the motion modeling and simulation of the heave platform by connecting the two points with a straight line segment. Step 3: In the simulation environment of Step 2, add the aircraft landing motion model, calculate the position information of the aircraft relative to the heave and sway platform in real time, determine the landing result based on the position information, and generate a simulation diagram. Step 4: Based on Step 3, for the landing simulation process of the aircraft landing on the platform, when the horizontal coordinate of the aircraft is between the horizontal coordinates corresponding to the two ends of the heave platform, calculate the vertical distance between the aircraft and the heave platform. When the vertical distance is not greater than 0.1m, calculate the height and tilt angle of the heave platform and the distance between the aircraft and the two ends of the heave platform, and generate relevant simulation diagrams. Step 5: Based on Step 3, for the landing simulation process of the aircraft flying over the platform, calculate the vertical distance between the aircraft and the ground. When the vertical distance is not greater than 0.1m, calculate the height and tilt angle of the heave platform and the relative position of the aircraft and the heave platform at this moment, and generate relevant simulation diagrams. Step 6: Integrate the aircraft dynamic platform landing simulation function implemented in Steps 2 to 5 to establish a functional module; the input information of this module is the parameters describing the motion of the heave platform and the longitudinal motion of the aircraft, and the output information is the data reflecting the landing result of the aircraft facing the heave platform.

[0007] Compared with existing technologies, the method provided by this invention can accurately model the position and attitude of the heave platform in real time, calculate the relative position of the aircraft and the heave platform, demonstrate the scenario of the aircraft landing facing the heave platform, and accurately calculate the landing point information. The parameters involved, such as platform radius, swing amplitude, and heave amplitude, can be set and adjusted independently, which facilitates simulation analysis under different working conditions. Therefore, it has strong engineering applicability and repeatability. Attached Figure Description

[0008] To more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings used in the following description of the embodiments will be briefly introduced. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0009] Figure 1 A schematic diagram of the simulation method for longitudinal motion of an aircraft landing on a heave-and-sway platform, provided in an embodiment of the present invention. Figure 2 This is a simulation diagram of the motion of the heave-swing platform provided in an embodiment of the present invention; Figure 3 A simulation diagram of an aircraft "crashing" as provided in an embodiment of the present invention; Figure 4 An illustration of an aircraft landing on a heave-and-swing platform, provided in an embodiment of the present invention. Figure 5 This is a rendering of the aircraft landing on the ground after flying over the heave platform, as provided in an embodiment of the present invention. Figure 6 A schematic diagram of the interface of the "Aircraft Dynamic Platform Landing Simulation Module" provided in an embodiment of the present invention; Figure 7 In this embodiment of the invention, the "aircraft dynamic platform landing simulation module" is used for analysis. Figure 4 The diagram shows the interface illustrating the aircraft's landing process. Detailed Implementation

[0010] 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 a part of the embodiments of the present invention, and not all of them, and do not constitute a limitation on the present invention. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort are within the protection scope of the present invention.

[0011] First, the following explanations are provided for the terms that may be used in this article: The term "and / or" means that either or both can be achieved simultaneously. For example, X and / or Y means that it includes both "X" or "Y" as well as the three cases of "X and Y".

[0012] The terms "comprising," "including," "containing," "having," or other similar semantic descriptions should be interpreted as non-exclusive inclusion. For example, including a technical feature element (such as raw material, component, ingredient, carrier, dosage form, material, size, part, component, mechanism, device, step, process, method, reaction conditions, processing conditions, parameter, algorithm, signal, data, product or article of manufacture, etc.) should be interpreted as including not only the expressly listed technical feature element, but also other technical feature elements that are not expressly listed and are well-known in the art.

[0013] The term "composed of" excludes any technical features not expressly listed. When used in a claim, it closes the claim to exclude all technical features other than those expressly listed, except for associated conventional impurities. If the term appears only in a clause of a claim, it limits the claim to the elements expressly listed in that clause; elements recited in other clauses are not excluded from the overall claim.

[0014] The technical solution provided by this invention will be described in detail below. Contents not described in detail in the embodiments of this invention are prior art known to those skilled in the art. Where specific conditions are not specified in the embodiments of this invention, they shall be performed according to conventional conditions in the art or conditions recommended by the manufacturer.

[0015] like Figure 1 The diagram shown is a schematic flowchart of a simulation method for the longitudinal motion of an aircraft landing on a heave-and-sway platform, provided in an embodiment of the present invention. The method includes: Step 1: Determine the geometric configuration of the heave platform. In a two-dimensional plane, model the heave platform as a straight line segment whose length does not change with the movement of the platform. Model the support below the heave platform as an isosceles triangle, with the vertex of the isosceles triangle coinciding with the midpoint of the straight line segment. In this step, the heave platform is referred to simply as the platform. Since the simulation is conducted on the longitudinal motion process of the aircraft landing, that is, the motion of both the aircraft and the platform is restricted to a two-dimensional space (plane). The platform is modeled as a rigid straight line segment of length 2R, where R is the longitudinal distance from the center of the platform to its edge. The length of the platform remains constant during the motion process, that is, the platform will not undergo expansion, contraction or bending deformation, and has only two degrees of freedom in the two-dimensional plane: rotation (swing) around the center point and translation (heave) in the vertical direction. The support structure under the platform is modeled as an isosceles triangle with a vertex angle of 30° and a base angle of 75°. The base of the triangle is horizontal and close to the ground, and the vertex always coincides with the midpoint of the platform. The triangle expands and contracts as the midpoint of the platform rises and falls, but the size of the vertex angle and the base angle remains constant. The instantaneous height of the platform's midpoint relative to the ground, i.e., the height of the triangle's vertex relative to its base, is denoted as the function h(t), where t represents time. h(t) reflects the platform's rising and falling pattern. The platform's swaying motion can be achieved by rotating the platform around its center point. These two motions are independent processes.

[0016] Step 2: Based on Step 1, calculate the spatial positions of the platform center and both ends according to the lifting height of the midpoint of the heave platform and the tilt angle of the heave platform relative to the horizontal plane. Then, combined with the positions of the two ends of the bottom edge of the support, complete the motion modeling and simulation of the heave platform by connecting the two points with a straight line segment. In this step, the mathematical models of both the platform and the support are established in the ground coordinate system O-xy. The bottom edge of the support is always on the x-axis of the ground coordinate system, and the coordinates of the midpoint of the bottom edge are the origin of the coordinate system (0,0). Initially, the platform is parallel to the x-axis of the ground coordinate system, and the platform's height above the ground is H0. Assume the platform's sway angle θ around its midpoint follows a sinusoidal law, i.e.: (1) In the formula, A θ f represents the swing amplitude. θ t is the oscillation frequency; t is time; when the left end of the platform is higher than the horizontal position of the platform. θ Take the positive value, otherwise... θ Taking negative values, during the platform's swaying process without heave, the positions of its left and right ends in the ground coordinate system are related to the swaying angle, with the coordinates as follows: Left end: ; Right end: ; R is the longitudinal distance from the center to the edge of the heave-swing platform; Based on the established platform sway model, a heave motion model is superimposed, and the heave displacement of the platform center point is assumed. Following a sinusoidal law, given the initial height H0 of the platform above the ground, we obtain: (2) In the formula, A y f represents the heave or sag. y The frequency of rise and fall; Then the coordinates (x, y) of any point on the platform in the ground coordinate system satisfy: (3) In the formula, ξ is the horizontal distance from any point on the platform to the center point of the platform; Therefore, considering the heave and sway motion of the swing platform, the coordinates of the left end of the heave and sway platform are obtained. and right-hand coordinates Satisfy the following formula: (4) To ensure the platform does not touch the ground during the combined swaying and heaving motion, a constraint is imposed on the amplitude of the swaying angle: Let the platform's heaving amplitude be A. y If the initial height above the ground is less than H0, then the minimum height of the platform's center point is H0-A. y The maximum sway angle θ of the platform max Should meet: (5) That is, the maximum value of the swing angle. Should be smaller In actual simulations, when H0 and A are clearly defined... y After taking the value of , the rocking angle (tilt angle) range of change No more than ; Based on the mathematical description of the motion process of the heave-swing platform, a motion diagram of the heave-swing platform is drawn according to the position coordinate relationship of key points. The specific process is as follows: ① Determine the instantaneous coordinates of the center point, left end, and right end of the heave platform in the ground coordinate system; where the coordinates of the platform center point are: The coordinates of the left and right ends of the platform are calculated using formula (4); ② Draw a straight line segment with the left and right ends of the platform as the two endpoints, and use this straight line segment to represent the heave and sway platform; in the Matlab software environment, use the plot function to connect the two known coordinate points into a straight line segment.

[0017] ③ Draw the platform support structure. The geometry of the support structure is an isosceles triangle, with its vertex coinciding with the midpoint of the heave-swing platform. The vertex coordinates are... The triangle has a vertex angle of 30°, a base angle of 75°, and its base lies on the x-axis of the ground coordinate system; when the vertex height... Given the given information, determine the coordinates of the left and right endpoints of the base of the triangle on the ground coordinate system based on geometric relationships. and Then connect the two ends of the base to the vertex to form straight line segments, thus constructing the supporting structure of the isosceles triangle.

[0018] like Figure 2 The figure shown is a simulation diagram of the heave-and-sway table motion provided in an embodiment of the present invention, obtained through simulation on the Simulink platform of Matlab software. Figure 2 The horizontal and vertical axes of the coordinate system were automatically generated by Matlab software. The line segment with the vertex of the triangular support as its midpoint is used as the heave-swing platform. The simulation initialization parameters are: H0=10m, R=20m, A y =5m, f y =f θ =π / 3Hz, A θ =10° (less than by) The calculated upper limit is 14.47°. The simulation stopped at 10 seconds, at which point the height of the platform's center point above the ground was... The platform's sway angle is 5.57m. θ It is -8.62°, such as Figure 2 As shown.

[0019] Step 3: In the simulation environment of Step 2, add the aircraft landing motion model, calculate the position information of the aircraft relative to the heave and sway platform in real time, determine the landing result based on the position information, and generate a simulation diagram. In this step, the aircraft landing motion model refers to the mathematical model that simulates the aircraft landing process. It is general and does not restrict the specific landing method. Furthermore, the aircraft's motion is simplified to the motion of a point mass, ignoring the aircraft's volume and specific structure. The known position coordinates of the aircraft are... The coordinates of the left and right ends of the heave and swing platform are respectively and For any point on the platform, its x-coordinate... x The corresponding ordinate can be calculated. for: (6) The specific methods for determining the type of aircraft landing result are as follows: 1) Aircraft crash situation During the flight of the aircraft toward the heave platform, the position of the aircraft and the attitude information of the heave platform are acquired in real time. When the horizontal coordinate of the aircraft... x-axis of the platform's left end When they are equal for the first time, compare the longitudinal coordinates of the spacecraft. The vertical coordinate of the left end of the platform Size: If Not greater than If the simulation fails, it indicates that the aircraft is unable to board the platform, which is considered a "crash". At this point, the simulation is terminated and a corresponding simulation effect diagram is provided. Note: Because the simulation simplifies the aircraft's motion to that of a point mass, the actual landing conditions are considered when determining whether the aircraft has crashed. It can be considered that and Equal, and when It can be considered that ; 2) The situation where the aircraft lands on the platform Under the premise that the conditions for the aircraft to "crash" are not met, when the horizontal coordinate of the aircraft... satisfy At that time, calculate the vertical distance of the aircraft relative to the platform surface. : (7) In the formula, This represents the ordinate value corresponding to the point on the platform that has the same x-coordinate as the aircraft; Because the simulation environment simplifies the aircraft's motion to the motion of a point mass, when determining whether the aircraft has landed on the platform, if... If the simulation fails, it is considered that the aircraft has made contact with the platform surface and has successfully landed on the platform. At this point, the simulation is terminated and the corresponding simulation effect diagram is given. 3) The situation of the aircraft flying over the platform Throughout the simulation, if the aircraft neither "crashes" nor meets the condition of "landing on the platform," it is determined that the aircraft has landed after flying over the platform, and a corresponding simulation effect diagram is provided.

[0020] Taking the "crash" scenario as an example, such as Figure 3 The image shown is a simulation of an aircraft "crashing" according to an embodiment of the present invention. Figure 3 Obtained through the Simulink platform of Matlab software. Figure 3 Initialization parameters of the simulated heave-swing table motion and Figure 2 To maintain consistency, the initial parameters for the aircraft landing were set as follows: at the start of the simulation, the horizontal distance between the aircraft and the platform center was L = -600m, the altitude above the ground was H = 41m, the flight speed remained constant at V = 45m / s, and the flight path maintained a 3° angle with the ground (i.e., track angle γ = -3°). After 12.63 seconds of simulation, the aircraft reached... Figure 3 At the dot at the end of the dashed line, the dashed line represents part of the spacecraft's trajectory before 12.63 seconds, plotted using the `plot` function in Matlab software based on the horizontal and vertical coordinates of the flight trajectory. At this point, the horizontal coordinate of the spacecraft's position is equal to the horizontal coordinate of the left end of the platform, thus the coordinates of the left end of the platform are calculated. The coordinates of the spacecraft are (-19.79, 16.90). The altitude is (-19.89, 10.59), which means the aircraft's altitude is obviously lower than the altitude of the left end of the platform. Therefore, it can be determined that the aircraft will "crash".

[0021] Step 4: Based on Step 3, for the landing simulation process of the aircraft landing on the platform, when the horizontal coordinate of the aircraft is between the horizontal coordinates corresponding to the two ends of the heave platform, calculate the vertical distance between the aircraft and the heave platform. When the vertical distance is not greater than 0.1m, calculate the height and tilt angle of the heave platform and the distance between the aircraft and the two ends of the heave platform, and generate relevant simulation diagrams. In this step, the aircraft trajectory data is known; that is, for each simulation sampling time, the horizontal and vertical coordinates of the aircraft's position are known, and the vertical distance between the aircraft and the platform at a certain sampling time is also known. At that time, it is considered that the aircraft has made contact with the platform, that is, the aircraft has landed on the platform; Based on the landing time of the aircraft, the corresponding platform tilt angle can be calculated using formula (1). The height of the platform center point when the aircraft contacts the heave platform is calculated using formula (2). And the coordinates of the left end of the platform at this time are calculated by formula (4). and right-hand coordinates Then, based on the spacecraft's position at the moment of landing, i.e., the coordinates of the contact point... Calculate the distance from the contact point to the left and right ends of the platform. and for: (8) Based on the above parameters, a simulation can be generated to show the landing effect of the aircraft on the heave platform, presenting the landing point and platform attitude information of the aircraft during landing.

[0022] like Figure 4 The image shown is an illustration of the aircraft landing on a heave-and-swing platform according to an embodiment of the present invention, obtained using the Simulink platform of Matlab software. Figure 4 Initialization parameters of the simulated heave-swing table motion and Figure 2 The same, and in Figure 3 Based on the flight path shown, a sinusoidal wave perpendicular to the steady-state path was superimposed to simulate the turbulent motion of the aircraft during approach. The corresponding flight speed of the steady-state path is 53 m / s. Figure 4 In the simulation, the spacecraft lands on the heave platform at 11.33 seconds, corresponding to the landing coordinates (10.99, 8.11). At this time, the platform's center point is at an altitude of... yaw angle θ = -6.43°, the landing point is 32.78m from the left end and 7.12m from the right end of the platform.

[0023] Step 5: Based on Step 3, for the landing simulation process of the aircraft flying over the platform, calculate the vertical distance between the aircraft and the ground. When the vertical distance is not greater than 0.1m, calculate the height and tilt angle of the heave platform and the relative position of the aircraft and the heave platform at this moment, and generate relevant simulation diagrams. In this step, the aircraft trajectory data is known; that is, for each simulation sampling time, the horizontal and vertical coordinates of the aircraft's position are known, and the vertical distance between the aircraft and the ground at a certain sampling time is also known. At that time, it is assumed that the aircraft flew over the platform and landed on the ground; Based on the aircraft's landing time, the corresponding platform tilt angle can be calculated using formula (1). The height of the platform center point when the aircraft touches the ground is calculated using formula (2). The distances from the contact point to the left and right ends of the platform are calculated using formula (8). and ; Based on the above parameters, a simulation can be generated to show the effect of the aircraft landing on the ground after flying over the platform.

[0024] like Figure 5The image shown is an illustration of the aircraft landing on the ground after flying over the heave platform, as provided in an embodiment of the present invention. This image was obtained using the Simulink platform of Matlab software. Figure 5 In the simulation, the initialization parameters of the heave-swing table motion are... Figure 2 The same, and in Figure 3 Based on the flight path shown, a sinusoidal wave perpendicular to the steady-state path was superimposed to simulate the turbulent motion of the aircraft during approach. The corresponding steady-state flight speed is 60 m / s. The aircraft lands at 12.91 s, corresponding to the landing point coordinates... The value is (186.14, 0.09), at which point the height of the platform's center point is... yaw angle θ =8.09°, the distances from the left and right ends of the platform where the aircraft landed were 206.6m and 166.7m, respectively.

[0025] Step 6: Integrate the aircraft dynamic platform landing simulation function implemented in Steps 2 to 5 to establish a functional module; the input information of this module is the parameters describing the motion of the heave platform and the longitudinal motion of the aircraft, and the output information is the data reflecting the landing result of the aircraft facing the heave platform.

[0026] In this step, specifically, the Subsystem tool in the Simulink platform of Matlab software can be used to build a simulation module for the landing of the aircraft's dynamic platform, such as... Figure 6 The diagram shown is an interface diagram of the "Aircraft Motion Platform Landing Simulation Module" provided in an embodiment of the present invention. The parameters describing the motion of the heave and sway platform and the longitudinal motion of the aircraft include: platform radius, platform heave amplitude, platform heave frequency, platform sway amplitude, platform sway frequency, initial height of the platform center, and x and y coordinates of the aircraft position. Data reflecting the landing results of an aircraft facing the heave platform include: whether it crashed, whether it flew over the platform, landing time, landing altitude, platform tilt angle at landing time, distance from the left end of the platform to the landing point, distance from the right end of the platform to the landing point, and horizontal distance from the center of the platform to the landing point. The above output information can not only intuitively represent whether the aircraft has successfully landed on the moving swing platform, but also accurately provide the aircraft's position data relative to the platform when landing.

[0027] like Figure 6 As shown, corresponding information is set for whether the aircraft crashed and whether it flew over the platform: "1" represents "yes" and "0" represents "no". When the module outputs the simulation result of the aircraft landing as "crashed", in the output information column, except for the first one which displays "1" and the second one which displays "0", all other information bars display 9999.

[0028] like Figure 7 The illustration shows an embodiment of the present invention using the "aircraft dynamic platform landing simulation module" for analysis. Figure 4 The diagram shows the interface for the aircraft's landing, including module input parameters. Figure 4 The corresponding simulation initialization parameters are consistent, and the module output information is the same as... Figure 4 The content matches perfectly.

[0029] This invention also provides an electronic device, including a memory and a processor, wherein the memory stores a computer program and the processor is configured to run the computer program to perform the method.

[0030] This invention also provides a computer storage medium storing a plurality of instructions adapted for loading and executing the method by a processor.

[0031] It is worth noting that the contents not described in detail in the embodiments of the present invention belong to the prior art known to those skilled in the art.

[0032] In summary, the method provided by the embodiments of the present invention can accurately model the position and attitude of the heave platform in real time, calculate the relative position of the aircraft and the heave platform, demonstrate the scenario of the aircraft landing facing the heave platform, and accurately calculate the landing point information. The parameters involved, such as the platform radius, swing amplitude, and heave amplitude, can be set and adjusted independently, which facilitates simulation analysis under different working conditions. Therefore, it has strong engineering applicability and repeatability.

[0033] The above description is merely a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in the present invention should be included within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be determined by the scope of the claims. The information disclosed in the background section is intended only to enhance the understanding of the overall background technology of the present invention and should not be construed as an admission or implication in any way that such information constitutes prior art known to those skilled in the art.

Claims

1. A method for simulating the longitudinal motion of an aircraft landing on a heave-and-sway platform, characterized in that, The method includes: Step 1: Determine the geometric configuration of the heave platform. In a two-dimensional plane, model the heave platform as a straight line segment whose length does not change with the movement of the platform. Model the support below the heave platform as an isosceles triangle, with the vertex of the isosceles triangle coinciding with the midpoint of the straight line segment. Step 2: Based on Step 1, calculate the spatial positions of the platform center and both ends according to the lifting height of the midpoint of the heave platform and the tilt angle of the heave platform relative to the horizontal plane. Then, combined with the positions of the two ends of the bottom edge of the support, complete the motion modeling and simulation of the heave platform by connecting the two points with a straight line segment. Step 3: In the simulation environment of Step 2, add the aircraft landing motion model, calculate the position information of the aircraft relative to the heave and sway platform in real time, determine the landing result based on the position information, and generate a simulation diagram. Step 4: Based on Step 3, for the landing simulation process of the aircraft landing on the platform, when the horizontal coordinate of the aircraft is between the horizontal coordinates corresponding to the two ends of the heave platform, calculate the vertical distance between the aircraft and the heave platform. When the vertical distance is not greater than 0.1m, calculate the height and tilt angle of the heave platform and the distance between the aircraft and the two ends of the heave platform, and generate relevant simulation diagrams. Step 5: Based on Step 3, for the landing simulation process of the aircraft flying over the platform, calculate the vertical distance between the aircraft and the ground. When the vertical distance is not greater than 0.1m, calculate the height and tilt angle of the heave platform and the relative position of the aircraft and the heave platform at this moment, and generate relevant simulation diagrams. Step 6: Integrate the aircraft dynamic platform landing simulation function implemented in Steps 2 to 5 to establish a functional module; the input information of this module is the parameters describing the motion of the heave platform and the longitudinal motion of the aircraft, and the output information is the data reflecting the landing result of the aircraft facing the heave platform.

2. The simulation method for longitudinal motion of an aircraft landing on a heave-and-sway platform according to claim 1, characterized in that, In step 1, the heave-swinging platform is referred to as the platform. The platform is modeled as a rigid straight line segment with a length of 2R, where R is the longitudinal distance from the center of the platform to the edge of the platform. The length of the platform remains constant during the motion, that is, the platform will not undergo expansion, contraction or bending deformation, and has only two degrees of freedom in the two-dimensional plane: rotation about the center point and translation along the vertical direction. The support structure under the platform is modeled as an isosceles triangle with a vertex angle of 30° and a base angle of 75°. The base of the triangle is horizontal and close to the ground, and the vertex always coincides with the midpoint of the platform. The triangle expands and contracts as the midpoint of the platform rises and falls, but the size of the vertex angle and the base angle remains constant. The instantaneous height of the platform's midpoint relative to the ground, i.e., the height of the triangle's vertex relative to its base, is denoted as the function h(t), where t represents time. h(t) reflects the platform's rising and falling pattern. The platform's swaying motion can be achieved by rotating the platform around its center point. These two motions are independent processes.

3. The simulation method for longitudinal motion of an aircraft landing on a heave-and-sway platform according to claim 1, characterized in that, In step 2, the mathematical models of both the platform and the support are established in the ground coordinate system O-xy. The bottom edge of the support is always on the x-axis of the ground coordinate system, and the coordinates of the midpoint of the bottom edge are the origin of the coordinate system (0,0). Initially, the platform is parallel to the x-axis of the ground coordinate system, and the platform's height above the ground is H0. Assume the platform's sway angle θ around its midpoint follows a sinusoidal law, i.e.: （1） In the formula, A θ f represents the swing amplitude. θ t is the swing frequency; t is time. When the left end of the platform is higher than the horizontal position of the platform θ Take the positive value, otherwise... θ Taking negative values, during the platform's swaying process without heave, the positions of its left and right ends in the ground coordinate system are related to the swaying angle, with the coordinates as follows: Leftmost: ; Rightmost: ; R is the longitudinal distance from the center to the edge of the heave-swing platform; Based on the established platform sway model, a heave motion model is superimposed, and the heave displacement of the platform center point is assumed. Following a sinusoidal law, given the initial height H0 of the platform above the ground, we obtain: （2） In the formula, A y f represents the heave or sag. y The frequency of rise and fall; Then the coordinates (x, y) of any point on the platform in the ground coordinate system satisfy: （3） In the formula, ξ is the horizontal distance from any point on the platform to the center point of the platform; Therefore, considering the heave and sway motion of the swing platform, the coordinates of the left end of the heave and sway platform are obtained. and right-hand coordinates Satisfy the following formula: （4） To ensure the platform does not touch the ground during the combined swaying and heaving motion, a constraint is imposed on the amplitude of the swaying angle: Let the platform's heaving amplitude be A. y If the initial height above the ground is less than H0, then the minimum height of the platform's center point is H0-A. y The maximum sway angle θ of the platform max It should meet the following requirements: （5） That is, the maximum value of the swing angle. Should be smaller ; Based on the mathematical description of the motion process of the heave-swing platform, a motion diagram of the heave-swing platform is drawn according to the position coordinate relationship of key points. The specific process is as follows: ① Determine the instantaneous coordinates of the center point, left end, and right end of the heave platform in the ground coordinate system; where the coordinates of the platform center point are: The coordinates of the left and right ends of the platform are calculated using formula (4); ② Draw a straight line segment with the left end and the right end of the platform as the two endpoints, and use this straight line segment to represent the heave and sway platform; ③ Draw the platform support structure. The geometry of the support structure is an isosceles triangle, with its vertex coinciding with the midpoint of the heave-swing platform. The vertex coordinates are... The triangle has a vertex angle of 30°, a base angle of 75°, and its base lies on the x-axis of the ground coordinate system; when the vertex height... Given the given information, determine the coordinates of the left and right endpoints of the base of the triangle on the ground coordinate system based on geometric relationships. and Then connect the two ends of the base to the vertex to form straight line segments, thus constructing the supporting structure of the isosceles triangle.

4. The simulation method for longitudinal motion of an aircraft landing on a heave-and-sway platform according to claim 3, characterized in that, In step 3, the aircraft landing motion model refers to the mathematical model that simulates the aircraft's landing motion process. It simplifies the aircraft's motion to that of a point mass, ignoring the aircraft's volume and specific structure. The known position coordinates of the aircraft are... The coordinates of the left and right ends of the heave and swing platform are respectively and For any point on the platform, its x-coordinate... x The corresponding ordinate can be calculated. for: （6） The specific methods for determining the type of aircraft landing result are as follows: 1) Aircraft crash situation During the flight of the aircraft toward the heave platform, the position of the aircraft and the attitude information of the heave platform are acquired in real time. When the horizontal coordinate of the aircraft... x-coordinate of the left end of the platform When they are equal for the first time, compare the longitudinal coordinates of the aircraft. The vertical coordinate of the left end of the platform Size: If Not greater than If the simulation fails, it indicates that the aircraft is unable to board the platform, which is considered a "crash". At this point, the simulation is terminated and a corresponding simulation effect diagram is provided. 2) The situation where the aircraft lands on the platform Assuming the conditions for the aircraft to "crash" are not met, when the horizontal coordinate of the aircraft... satisfy At that time, calculate the vertical distance of the aircraft relative to the platform surface. : （7） In the formula, This represents the ordinate value corresponding to the point on the platform that has the same x-coordinate as the aircraft; When determining whether an aircraft has landed on a platform, if If the simulation fails, it is considered that the aircraft has made contact with the platform surface and has successfully landed on the platform. At this point, the simulation is terminated and the corresponding simulation effect diagram is given. 3) The situation of the aircraft flying over the platform Throughout the simulation, if the aircraft neither "crashes" nor meets the condition of "landing on the platform," it is determined that the aircraft has landed after flying over the platform, and a corresponding simulation effect diagram is provided.

5. The simulation method for longitudinal motion of an aircraft landing on a heave-and-sway platform according to claim 4, characterized in that, In step 4, the aircraft trajectory data is known; that is, for each simulation sampling time, the horizontal and vertical coordinates of the aircraft's position are known, and the vertical distance between the aircraft and the platform at a certain sampling time is also known. At that time, it is considered that the aircraft has made contact with the platform, that is, the aircraft has landed on the platform; Based on the landing time of the aircraft, the corresponding platform tilt angle can be calculated using formula (1). The height of the platform center point when the aircraft contacts the heave platform is calculated using formula (2). And the coordinates of the left end of the platform at this time are calculated by formula (4). and right-hand coordinates Then, based on the spacecraft's position at the moment of landing, i.e., the coordinates of the contact point... Calculate the distance from the contact point to the left and right ends of the platform. and for: （8） Based on the above parameters, a simulation can be generated to show the landing effect of the aircraft on the heave platform, presenting the landing point and platform attitude information of the aircraft during landing.

6. The simulation method for longitudinal motion of an aircraft landing on a heave-and-sway platform according to claim 5, characterized in that, In step 5, the aircraft trajectory data is known; that is, for each simulation sampling time, the horizontal and vertical coordinates of the aircraft's position are known, and the vertical distance between the aircraft and the ground at a certain sampling time is also known. At that time, it is assumed that the aircraft flew over the platform and landed on the ground; Based on the aircraft's landing time, the corresponding platform tilt angle can be calculated using formula (1). The height of the platform center point when the aircraft touches the ground is calculated using formula (2). The distances from the contact point to the left and right ends of the platform are calculated using formula (8). and ; Based on the above parameters, a simulation can be generated to show the effect of the aircraft landing on the ground after flying over the platform.

7. The simulation method for longitudinal motion of an aircraft landing on a heave-and-sway platform according to claim 5, characterized in that, In step 6, the parameters describing the motion of the heave and sway platform and the longitudinal motion of the aircraft include: platform radius, platform heave amplitude, platform heave frequency, platform sway amplitude, platform sway frequency, initial height of the platform center, and the x and y coordinates of the aircraft position. The main parameters describing the motion of the heave platform and the longitudinal motion of the aircraft include: whether it crashes, whether it flies over the platform, landing time, landing altitude, platform tilt angle at landing time, distance from the landing point to the left end of the platform, distance from the landing point to the right end of the platform, and horizontal distance from the landing point to the center of the platform. For example, for whether the aircraft crashed or flew over the platform, corresponding information is set: "1" represents "yes" and "0" represents "no". When the module outputs the simulation result of the aircraft landing as "crash", in the output information column, except for the first one which displays "1" and the second one which displays "0", all other information bars display 9999.

8. An electronic device comprising a memory and a processor, characterized in that, The memory stores a computer program, and the processor is configured to run the computer program to perform the method according to any one of claims 1 to 7.

9. A computer storage medium, characterized in that, The computer storage medium stores a plurality of instructions adapted for loading by a processor and executing the method of any one of claims 1 to 7.

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