Ground rapid trimming method for flight simulator equipment

Abstract

The present invention belongs to the field of ground trim technology for flight simulators, and specifically relates to a method for rapid ground trimming of flight simulator equipment, aiming to solve the problem of long ground trimming time and low efficiency of traditional flight simulators. The present invention obtains the airport environment, simulator body and landing gear tire parameters, constructs a spring oil damping model to determine the static landing gear compression, and combines the coordinate system transformation with the vertical distance formula to calculate the initial ground height difference, and obtains the initial trim height value of the flight simulator's center of gravity. Based on the dynamic landing gear compression, the ground longitudinal, lateral and normal forces are calculated in a piecewise manner to obtain the total ground force and total torque exerted on the aircraft, and the total force and total torque of the aircraft body axis; the gradient descent method is used to iteratively solve the aircraft attitude angle and set it to the flight simulator, with the total force and total torque returning to zero as the convergence condition. The present invention significantly shortens the ground trimming time and improves the use efficiency and training response speed of the flight simulator.

Description

Technical Field

[0001] The invention belongs to the technical field of ground trimming of flight simulators, and in particular relates to a method for rapid ground trimming of flight simulator equipment. Background Art

[0002] Ground trimming of a flight simulator is a mechanical trimming method that repositions the aircraft to its takeoff position on the ground. It requires solving the force balance of thrust, ground force, and gravity to obtain the parameters that need to be set for the aircraft: aircraft height above the ground and aircraft attitude angle.

[0003] At present, the traditional ground trimming method of simulators is to build a model of the aircraft's ground control characteristics while continuously and iteratively adjusting the aircraft's attitude angle and height from the ground to balance the total force and total torque, thereby achieving ground trimming.

[0004] However, the aircraft ground handling characteristics model involves the interaction between the landing gear, tires and the ground. The mathematical model is complex, and balancing must strictly follow a fixed process: first configure the visual system airport, then set the aircraft system parameters, and finally solve for force balance. This makes the traditional iterative balancing method have significant defects in engineering practice: there is a strong dependency between the steps, and it is necessary to wait for the previous step to be completed before moving forward; the force balance solution has many iterations, and ground trimming is time-consuming. In addition, to avoid abnormal overflow of parameter calculations, the initial altitude value needs to be manually set in the database, and manual debugging is required according to the altitude of different airport visual scenes. This is extremely inefficient and difficult to adapt to the needs of efficient simulator training. Technical improvements are urgently needed. Summary of the Invention

[0005] In order to solve the above-mentioned problems in the prior art, namely, the problems that conventional ground trimming of flight simulators is time-consuming and inefficient due to complex models, strong step dependency, multiple iterations, and the need for manual adjustment of the initial height, the present invention provides a first aspect of a method for rapid ground trimming of a flight simulator device, comprising the following steps:

[0006] Acquiring initial parameters related to ground trim of the flight simulator, the initial parameters including: airport environment parameters, flight simulator body parameters, and structural characteristic parameters of the landing gear and tires;

[0007] Calculating the flight simulator gravity based on the flight simulator body parameters, constructing a spring-oil damping model of the landing gear strut force, and then determining the static landing gear compression amount based on the force balance condition in a ground equilibrium state;

[0008] Determine the coordinates of the lowest point of the landing gear in the geodetic coordinate system and obtain the dynamic landing gear compression through transformation;

[0009] Calculate the initial ground clearance at the center of gravity of the flight simulator based on the static landing gear compression and the vertical distance of the tire contact point in the aircraft axis coordinate system when the landing gear is fully extended;

[0010] The initial height difference from the ground at the center of gravity of the flight simulator and the ground height are added to obtain an initial trim height value of the center of gravity of the flight simulator and set it to the flight simulator; based on the dynamic landing gear compression, the ground longitudinal force, lateral force, and normal force are calculated in a piecewise manner to obtain the total ground force and total moment acting on the aircraft; and based on the total ground force and total moment and other forces acting on the aircraft, the total force and total moment acting on the aircraft body axis are obtained;

[0011] Read the runway information, motion status information, and aircraft force information, combine the total force and total torque of the aircraft body axis, solve the aircraft attitude angle vector and set it to the flight simulator to complete the ground balancing of the flight simulator.

[0012] In some preferred embodiments, the static landing gear compression is determined according to the force balance condition by:

[0013] When the aircraft is in a static equilibrium state on the ground, the oil damping force is zero, the landing gear strut force is equal to the gravity and the air spring force, and the static landing gear compression is:

[0014] ;

[0015] ;

[0016] ;

[0017] Where, is gravity, is the aircraft mass, is the acceleration due to gravity, is the cylinder volume when the strut is not compressed, is the volume of the buffer cylinder, is the cross-sectional area of ​​the cylinder, is the static landing gear compression, is the compression of the buffer pillar, is the cylinder pre-charge pressure, is the cylinder pressure, P0V0 =PV=cste, , that is, the spring-oil damping model, is the landing gear strut force, is the air spring force, is the oil damping force.

[0018] In some preferred embodiments, the coordinates of the lowest point of the landing gear in the geodetic coordinate system are determined, and the dynamic landing gear compression amount is obtained by transformation, which is as follows:

[0019] ;

[0020] ;

[0021] Where, is the coordinate of the wheel center in the body axis coordinate system when the landing gear is fully extended. is the tire rolling radius, is the coordinate of the center of gravity of the aircraft in the geodetic coordinate system, is the dynamic landing gear compression, is a sub-item in the direction cosine matrix.

[0022] In some preferred embodiments, the initial height difference from the ground at the center of gravity of the flight simulator is calculated as follows:

[0023] ;

[0024] ;

[0025] ;

[0026] in, is the coordinate of the tire contact point in the body axis coordinate system when the landing gear is fully extended. is the aircraft mass, is the acceleration due to gravity, is the cylinder volume when the strut is not compressed, is the cross-sectional area of ​​the cylinder, is the static landing gear compression, It is the cylinder pre-charge pressure.

[0027] In some preferred embodiments, based on the dynamic landing gear compression, the ground longitudinal force, lateral force, and normal force are calculated in a piecewise manner as follows:

[0028] The normal force is calculated based on the dynamic landing gear compression through the spring oil damping model; the normal force includes the tire / landing gear normal strut force ; Including air spring force, landing gear damping force; the landing gear damping force is based on Multiplying by the damping coefficient gives; , is the landing gear strut compression rate, is the aircraft's pitch angular velocity, is the aircraft's roll angular velocity, is the rate of change of altitude;

[0029] The lateral force includes the tire lateral force, which is calculated as follows:

[0030] ;

[0031] ;

[0032] ;

[0033] ;

[0034] ;

[0035] Where, is the lateral force exerted by the ground on the aircraft tires, is the tire / landing gear normal strut force, is the effective friction coefficient, is the side force attenuation coefficient, is the lateral force ratio, is the tire sideslip angle, is the sideslip angle ratio, is the side slip ratio symbol, is the turning gain;

[0036] The ground longitudinal force is calculated as follows:

[0037] In the ground trim state, based on the condition that the turning angle is zero, the ground longitudinal force is calculated according to the constraints that the engine idle thrust is less than or equal to the maximum static friction and the ground longitudinal force is less than or equal to the maximum static friction. :

[0038] ;

[0039] Where, is the longitudinal ground force, is the static friction force, For the braking force, is the maximum static friction.

[0040] In some preferred embodiments, the method for calculating the total ground force and total moment is:

[0041] Calculate the forces acting on the landing gear in the body axis coordinate system through coordinate transformation :

[0042] ;

[0043] Where, is the transformation matrix from the NED coordinate system to the body axis coordinate system, is the transformation matrix from the wheel coordinate system to the NED coordinate system, is the force in the wheel coordinate system;

[0044] described Through the deflection angle Calculation, specifically:

[0045] ;

[0046] Component of the moment acting on the landing gear below the fuselage axis Calculated by the following formula:

[0047] ;

[0048] in, is the position vector of a single tire contact point in the body axis coordinate system, is the weight of a single tire under the axle of the aircraft body;

[0049] Total force on aircraft body axes Other forces on the aircraft Add the total ground force :

[0050] ;

[0051] Total moment of aircraft body axis Other moments acting on the aircraft Add the total ground moment :

[0052] ;

[0053] Where, 、 Both include engine thrust and aircraft weight.

[0054] In some preferred embodiments, if the forces in the wheel coordinate system include longitudinal forces , lateral force and normal force , then the force in the wheel coordinate system is for:

[0055] ;

[0056] If F is the unit force in the Y-axis direction in the wheel coordinate system, Install angles for landing gear struts, is the front wheel deflection angle, and the component of the ground force F under the body axis is:

[0057] .

[0058] In some preferred embodiments, the deflection angle The calculation method is:

[0059] ;

[0060] ;

[0061] Where, is the transformation matrix from the body axis coordinate system to the NED coordinate system. The components of the ground force F in the NED coordinate system and the body axis coordinate system are and , 、 、 They are The x, y, and z components in the NED coordinate system.

[0062] In some preferred embodiments, the position vector of the single tire contact point in the body axis coordinate system is obtained by:

[0063] Assume that the center coordinate of the wheel when the landing gear is naturally extended is , the tire rolling radius is , the landing gear compression is , for or Then the position vector of a single tire contact point is:

[0064] ;

[0065] in, is the dynamic landing gear compression, is the static landing gear compression.

[0066] In some preferred embodiments, the method of solving the attitude angle vector of the aircraft and setting it to the flight simulator to complete the ground trim of the flight simulator is as follows:

[0067] Read runway information, motion status information, aircraft force information, and obtain aircraft attitude state angle vector, where is the height, is the pitch angle, is the roll angle, is the yaw angle, and sets the iteration parameters, which include weight coefficient vector, learning rate, and termination condition parameters;

[0068] Calculate the cost function value based on the aircraft attitude angle vector and the weight coefficient vector, , where the weight coefficient vector , the total force vector of the aircraft body axis , the total moment vector of the aircraft body axis ;

[0069] A gradient vector is calculated based on the aircraft attitude angle vector and the cost function value to obtain a gradient value:

[0070] ;

[0071] ;

[0072] ;

[0073] ;

[0074] ;

[0075] Based on the current aircraft attitude angle vector , the gradient vector , learning rate , iterate the state vector according to the preset threshold as the termination condition, ; The preset thresholds include the cost function change threshold, the gradient threshold and the maximum number of iterations;

[0076] When the termination condition is met, the optimized aircraft attitude angle vector is obtained and set to the flight simulator. The total force and total moment of the aircraft body axis are zero, and the ground trim of the flight simulator is completed.

[0077] Beneficial effects of the present invention:

[0078] By acquiring parameters of the airport environment, the simulator, and the landing gear tires, a spring-oil damping model is constructed to determine the static landing gear compression. The initial ground clearance difference is calculated using a combination of coordinate system transformation and the vertical distance formula, which in turn yields the initial trim height of the flight simulator's center of gravity. This process eliminates traditional manual commissioning and achieves automated and precise calculation of the initial height, avoiding human error.

[0079] Based on the landing gear compression, a segmented approach is used to calculate the ground longitudinal, lateral, and normal forces. The stiffness coefficient is obtained using a real-time interpolation table to improve the accuracy of the mechanical model calculations. Furthermore, through coordinate transformation and moment synthesis algorithms, the total ground forces and moments acting on the aircraft are efficiently calculated, thereby obtaining the total forces and moments acting on the aircraft's shafting system.

[0080] The gradient descent method is used to iteratively solve the aircraft attitude angle, with the termination condition as the convergence condition, replacing the traditional step-by-step iterative method. This method fully automates data processing and parameter solution, greatly reducing the reliance on manual intervention in the balancing process, avoiding waiting delays between steps and mechanical balance iteration redundancy, and significantly shortening the ground balancing time compared to traditional methods, effectively improving the use efficiency of the flight simulator and the training response speed. BRIEF DESCRIPTION OF THE DRAWINGS

[0081] Other features, objects and advantages of the present application will become more apparent upon reading the detailed description of non-limiting embodiments made with reference to the following drawings:

[0082] Figure 1 The present invention is a flowchart of the steps of a method for rapid ground trimming of a flight simulator device. DETAILED DESCRIPTION

[0083] The present application will be further described in detail below with reference to the accompanying drawings and examples. It should be understood that the specific embodiments described herein are intended only to illustrate the relevant invention and are not intended to limit the invention. It should also be noted that, for ease of description, only portions relevant to the relevant invention are shown in the accompanying drawings.

[0084] It should be noted that, in the absence of conflict, the embodiments and features of the embodiments in this application can be combined with each other. The present application will be described in detail below with reference to the accompanying drawings and in combination with the embodiments.

[0085] In order to more clearly illustrate the ground rapid trimming method of the flight simulator device of the present invention, the following is a Figure 1 Each step in the embodiment of the present invention is described in detail.

[0086] The present invention proposes a method for rapid ground trimming of a flight simulator. Figure 1 , the method comprises the following steps:

[0087] Acquiring initial parameters related to ground trim of the flight simulator, the initial parameters including: airport environment parameters, flight simulator body parameters, and structural characteristic parameters of the landing gear and tires;

[0088] In this embodiment, the airport environmental parameters include airport runway information, which is obtained by loading the visual system into the database and can read the sea level pressure altitude of the current airport runway;

[0089] The flight simulator parameters include throttle lever position and aircraft environmental quality, which are obtained through the instructor station software shared memory;

[0090] The structural characteristic parameters of the landing gear and tire include the geometric characteristics of the landing gear / tire (such as size / size), the stiffness coefficient and damping coefficient of the landing gear strut / tire, and the friction coefficient, which are obtained by reading the difference data table.

[0091] Calculating the flight simulator gravity based on the flight simulator body parameters, constructing a spring-oil damping model of the landing gear strut force, and then determining the static landing gear compression amount based on the force balance condition in a ground equilibrium state;

[0092] In this embodiment, the static landing gear compression amount is determined according to the force balance condition by:

[0093] The spring oil damping model is:

[0094] ;

[0095] in, is the landing gear strut force, is the air spring force, is the oil damping force;

[0096] When the aircraft is in a static equilibrium state on the ground, the oil damping force is zero, and the landing gear strut force is equal to the gravity and the air spring force. The static landing gear compression is:

[0097] ;

[0098] ;

[0099] ;

[0100] Where, is gravity, is the aircraft mass, is the acceleration due to gravity, is the cylinder volume when the strut is not compressed, is the volume of the buffer cylinder, is the cross-sectional area of ​​the cylinder, is the static landing gear compression, is the compression of the buffer pillar, is the cylinder pre-charge pressure, is the cylinder pressure, P0V0 =PV=cste;

[0101] The method for determining the coordinates of the lowest point of the landing gear in the geodetic coordinate system and obtaining the dynamic landing gear compression amount through transformation is as follows:

[0102] ;

[0103] ;

[0104] Where, is the coordinate of the wheel center in the body axis coordinate system when the landing gear is fully extended. is the tire rolling radius, is the coordinate of the center of gravity of the aircraft in the geodetic coordinate system, is the dynamic landing gear compression, is the sub-item in the direction cosine matrix;

[0105] Based on the static landing gear compression and the vertical distance of the tire contact point in the aircraft axis coordinate system when the landing gear is fully extended, the initial ground clearance difference at the center of gravity of the flight simulator is calculated. , which is calculated as follows:

[0106] The coordinates of the tire contact point in the body axis coordinate system when the landing gear is fully extended are: : ;

[0107] The calculation formula of the vertical distance is:

[0108] ;

[0109] The static landing gear compression Substituting the vertical distance formula, we can obtain the initial ground clearance difference at the center of gravity of the flight simulator:

[0110] ;

[0111] in, is the coordinate of the tire contact point in the body axis coordinate system when the landing gear is fully extended. is the aircraft mass, is the acceleration due to gravity, is the cylinder volume when the strut is not compressed, is the cross-sectional area of ​​the cylinder, is the static landing gear compression, It is the cylinder pre-charge pressure;

[0112] Also included is the calculation of the landing gear strut compression rate:

[0113] ;

[0114] Where: is the landing gear strut compression rate, is the aircraft's pitch angular velocity, is the aircraft's roll angular velocity, is the rate of change of altitude;

[0115] The initial height difference from the ground at the center of gravity of the flight simulator and the ground height are added to obtain an initial trim height value of the center of gravity of the flight simulator and set it to the flight simulator; based on the dynamic landing gear compression, the ground longitudinal force, lateral force, and normal force are calculated in a piecewise manner to obtain the total ground force and total moment acting on the aircraft; and based on the total ground force and total moment and other forces acting on the aircraft, the total force and total moment acting on the aircraft body axis are obtained;

[0116] In this embodiment, the normal force is calculated based on the landing gear compression through the spring oil damping model; the normal force includes the tire / landing gear normal strut force ; Including air spring force, landing gear damping force; the air spring force adopts the The landing gear damping force is calculated according to Multiplying by the damping coefficient gives;

[0117] The lateral force includes the tire lateral force, which is calculated as follows:

[0118] ;

[0119] ;

[0120] ;

[0121] ;

[0122] ;

[0123] Where, is the lateral force exerted by the ground on the aircraft tires, is the tire / landing gear normal strut force, is the effective friction coefficient, its value is proportional to the braking force Related, see Table 1, is the side force attenuation coefficient, is the lateral force ratio, is the tire sideslip angle, is the sideslip angle ratio, is the side slip ratio symbol, when >0, =1; when <0, = -1. It is generally believed that The tires do not slip; When the tires slip, is the turning gain;

[0124] Table 1:

[0125]

[0126] Turn Gain for:

[0127] ;

[0128] in, is the reference friction coefficient, see Table 2, and N64 is the R-64 turning power, calculated by the following formula:

[0129] ;

[0130] ;

[0131] in, is the turning power coefficient, is the actual tire pressure, is the rated tire pressure, is the tire width;

[0132] Table 2:

[0133]

[0134] The ground longitudinal force is calculated as follows:

[0135] In the ground trim state, based on the condition that the turning angle is zero, the ground longitudinal force is calculated according to the constraints that the engine idle thrust is less than or equal to the maximum static friction and the ground longitudinal force is less than or equal to the maximum static friction. :

[0136] ;

[0137] Where, is the longitudinal ground force, is the static friction force, For the braking force, is the maximum static friction;

[0138] Calculating the total ground force and total moment of the landing gear about the body axis based on the ground longitudinal force, lateral force, and normal force;

[0139] In this embodiment, the method for calculating the total ground force and total moment is:

[0140] Calculate the forces acting on the landing gear in the body axis coordinate system through coordinate transformation :

[0141] ;

[0142] Where, is the transformation matrix from the NED coordinate system to the body axis coordinate system, is the transformation matrix from the wheel coordinate system to the NED coordinate system, is the force in the wheel coordinate system;

[0143] described Through the deflection angle Calculation, specifically:

[0144] ;

[0145] The components of the ground force F in the NED coordinate system and the body axis coordinate system are and ;

[0146] ;

[0147] Where, is the transformation matrix from the body axis coordinate system to the NED coordinate system;

[0148] Then, the deflection angle Calculated by the following formula:

[0149] ;

[0150] in, 、 、 They are The x, y and z components in the NED coordinate system;

[0151] If F is the unit force in the Y-axis direction in the wheel coordinate system, Install angles for landing gear struts, is the front wheel deflection angle, and the component of the ground force F under the body axis is:

[0152] ;

[0153] If the forces in the wheel coordinate system include longitudinal forces , lateral force and normal force , then the force in the wheel coordinate system is for:

[0154] ;

[0155] Component of the moment acting on the landing gear below the fuselage axis Calculated by the following formula:

[0156] ;

[0157] in, is the position vector of a single tire contact point in the body axis coordinate system, is the weight of a single tire under the axle of the fuselage. N can be a common tricycle landing gear, in which case it is 3;

[0158] The position vector of the single tire contact point in the body axis coordinate system is obtained through the difference data table, specifically: assuming that the center coordinate of the wheel when the landing gear is naturally extended is , the tire rolling radius is , the landing gear compression is , for or Then the position vector of a single tire contact point is:

[0159] ;

[0160] in, is the dynamic landing gear compression, is the static landing gear compression;

[0161] Total force on aircraft body axes Other forces on the aircraft Add the total ground force :

[0162] ;

[0163] Total moment of aircraft body axis Other moments acting on the aircraft Add the total ground moment :

[0164] ;

[0165] Where, 、 Both include engine thrust and aircraft weight;

[0166] The runway information, motion state information, and aircraft force information are read, and the gradient descent method is used to iterate continuously until the total ground force and total torque are zero, and the iteration is stopped to solve the aircraft attitude angle. The method is:

[0167] Step 1: Read the runway information (position, direction, size, runway information affects the ground terrain height setting), motion state information (position, speed, acceleration, motion state information affects the total ground force and total torque on the aircraft), aircraft force information (gravity, aerodynamic force, landing gear support force), and obtain the aircraft attitude angle vector ,in, is the height, is the pitch angle, is the roll angle, is the yaw angle, and the iteration parameters are set. The iteration parameters include the weight coefficient vector, the learning rate, the termination condition parameter, and the number of iterations k;

[0168] Step 2: Calculate the cost function value based on the aircraft attitude angle vector and the weight coefficient vector.

[0169] ;

[0170] Among them, the weight coefficient vector , the total force vector of the aircraft body axis , the total moment vector of the aircraft body axis ;

[0171] Step 3: Calculate the gradient vector based on the aircraft attitude angle vector and the cost function value to obtain the gradient:

[0172] ;

[0173] ;

[0174] ;

[0175] ;

[0176] ;

[0177] Step 4: Based on the current aircraft attitude angle vector , the gradient vector , learning rate , iterate the state vector according to the preset threshold as the termination condition, ; The preset thresholds include the cost function change threshold (1000), the gradient threshold (100) and the maximum number of iterations (20000);

[0178] Component expansion:

[0179] ;

[0180] ;

[0181] ;

[0182] ;

[0183] Constraints:

[0184] ;

[0185] ;

[0186] ;

[0187] ;

[0188] Step 5: When the termination condition is met, the optimized aircraft attitude angle vector is obtained and set to the flight simulator. The total force and total moment of the aircraft body axis are zero, and the ground balancing of the flight simulator is completed.

[0189] Although the various steps in the above embodiment are described in the above-mentioned order, those skilled in the art will understand that in order to achieve the effect of this embodiment, different steps do not have to be executed in such an order. They can be executed simultaneously (in parallel) or in a reverse order. These simple changes are within the scope of protection of the present invention.

[0190] Those skilled in the art should be able to appreciate that the modules and method steps of each example described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, computer software, or a combination of the two, and the programs corresponding to the software modules and method steps can be placed in random access memory (RAM), internal memory, read-only memory (ROM), electrically programmable ROM, electrically erasable programmable ROM, registers, hard disks, removable disks, CD-ROMs, or any other form of storage medium known in the art. In order to clearly illustrate the interchangeability of electronic hardware and software, the above description has generally described the components and steps of each example according to their functions. Whether these functions are performed in electronic hardware or software depends on the specific application and design constraints of the technical solution. Those skilled in the art may use different methods to implement the described functions for each specific application, but such implementation should not be considered to be beyond the scope of the present invention.

[0191] The terms "first", "second", etc. are used to distinguish similar objects, rather than to describe or indicate a particular order or sequence.

[0192] The term "comprise" or any other similar term is intended to cover non-exclusive inclusion such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed or inherent to such process, method, article, or apparatus.

[0193] Thus far, the technical solutions of the present invention have been described in conjunction with the preferred embodiments shown in the accompanying drawings. However, it will be readily understood by those skilled in the art that the scope of protection of the present invention is obviously not limited to these specific embodiments. Without departing from the principles of the present invention, those skilled in the art may make equivalent changes or substitutions to the relevant technical features, and the technical solutions after such changes or substitutions will fall within the scope of protection of the present invention.

Claims

1. A method for rapid ground trimming of a flight simulator, characterized in that: The method comprises the following steps: Acquiring initial parameters related to ground trim of the flight simulator, the initial parameters including: airport environment parameters, flight simulator body parameters, and structural characteristic parameters of the landing gear and tires; Calculating the flight simulator gravity based on the flight simulator body parameters, constructing a spring-oil damping model of the landing gear strut force, and then determining the static landing gear compression amount based on the force balance condition in a ground equilibrium state; Determine the coordinates of the lowest point of the landing gear in the geodetic coordinate system and obtain the dynamic landing gear compression through transformation; Calculate the initial ground clearance at the center of gravity of the flight simulator based on the static landing gear compression and the vertical distance of the tire contact point in the aircraft axis coordinate system when the landing gear is fully extended; The initial height difference from the ground at the center of gravity of the flight simulator and the ground height are added to obtain an initial trim height value of the center of gravity of the flight simulator and set it to the flight simulator; based on the dynamic landing gear compression, the ground longitudinal force, lateral force, and normal force are calculated in a piecewise manner to obtain the total ground force and total moment acting on the aircraft; and based on the total ground force and total moment and other forces acting on the aircraft, the total force and total moment acting on the aircraft body axis are obtained; Read the runway information, motion status information, and aircraft force information, combine the total force and total torque of the aircraft body axis, solve the aircraft attitude angle vector and set it to the flight simulator to complete the ground balancing of the flight simulator.

2. The ground rapid balancing method for a flight simulator device according to claim 1, characterized in that: The static landing gear compression is determined based on the force balance condition as follows: When the aircraft is in a static equilibrium state on the ground, the oil damping force is zero, the landing gear strut force is equal to the gravity and the air spring force, and the static landing gear compression is: ； ； ； Where, is gravity, is the aircraft mass, is the acceleration due to gravity, is the cylinder volume when the strut is not compressed, is the volume of the buffer cylinder, is the cross-sectional area of ​​the cylinder, is the static landing gear compression, is the compression of the buffer pillar, is the cylinder pre-charge pressure, is the cylinder pressure, P0V0 =PV=cste, , that is, the spring-oil damping model, is the landing gear strut force, is the air spring force, is the oil damping force.

3. The ground rapid trim method for a flight simulator device according to claim 1, characterized in that: The method for determining the coordinates of the lowest point of the landing gear in the geodetic coordinate system and obtaining the dynamic landing gear compression amount through transformation is as follows: ； ； Where, is the coordinate of the wheel center in the body axis coordinate system when the landing gear is fully extended. is the tire rolling radius, is the coordinate of the center of gravity of the aircraft in the geodetic coordinate system, is the dynamic landing gear compression, is a sub-item in the direction cosine matrix.

4. The ground rapid balancing method for a flight simulator according to claim 3, wherein: The initial height difference from the ground at the center of gravity of the flight simulator , which is calculated as follows: ； ； ； in, is the coordinate of the tire contact point in the body axis coordinate system when the landing gear is fully extended. is the aircraft mass, is the acceleration due to gravity, is the cylinder volume when the strut is not compressed, is the cross-sectional area of ​​the cylinder, is the static landing gear compression, It is the cylinder pre-charge pressure.

5. The ground rapid trim method for a flight simulator device according to claim 4, characterized in that: Based on the dynamic landing gear compression, the ground longitudinal force, lateral force, and normal force are calculated using a segmented method as follows: The normal force is calculated based on the dynamic landing gear compression through the spring oil damping model; the normal force includes the tire / landing gear normal strut force ; Including air spring force, landing gear damping force; the landing gear damping force is based on Multiplying by the damping coefficient gives; , is the landing gear strut compression rate, is the aircraft's pitch angular velocity, is the aircraft's roll angular velocity, is the rate of change of altitude; The lateral force includes the tire lateral force, which is calculated as follows: ； ； ； ； ； Where, is the lateral force exerted by the ground on the aircraft tires, is the tire / landing gear normal strut force, is the effective friction coefficient, is the side force attenuation coefficient, is the lateral force ratio, is the tire sideslip angle, is the sideslip angle ratio, is the side slip ratio symbol, is the turning gain; The ground longitudinal force is calculated as follows: In the ground trim state, based on the condition that the turning angle is zero, the ground longitudinal force is calculated according to the constraints that the engine idle thrust is less than or equal to the maximum static friction and the ground longitudinal force is less than or equal to the maximum static friction. : ； Where, is the longitudinal ground force, is the static friction force, For the braking force, is the maximum static friction.

6. The ground rapid trim method for a flight simulator device according to claim 1, characterized in that: The calculation method of the total ground force and total moment is: Calculate the forces acting on the landing gear in the body axis coordinate system through coordinate transformation : ； Where, is the transformation matrix from the NED coordinate system to the body axis coordinate system, is the transformation matrix from the wheel coordinate system to the NED coordinate system, is the force in the wheel coordinate system; described Through the deflection angle Calculation, specifically: ； Component of the moment acting on the landing gear below the fuselage axis Calculated by the following formula: ； in, is the position vector of a single tire contact point in the body axis coordinate system, is the weight of a single tire under the axle of the aircraft body; Total force on aircraft body axes Other forces on the aircraft Add the total ground force : ; Total moment of aircraft body axis Other moments acting on the aircraft Add the total ground moment : ； Where, 、 Both include engine thrust and aircraft weight.

7. The ground rapid trim method for a flight simulator according to claim 6, characterized in that: If the forces in the wheel coordinate system include longitudinal forces , lateral force and normal force , then the force in the wheel coordinate system is for: ； If F is the unit force in the Y-axis direction in the wheel coordinate system, Install angles for landing gear struts, is the front wheel deflection angle, and the component of the ground force F under the body axis is: 。 8. The method for rapid ground trimming of a flight simulator according to claim 6, wherein: The deflection angle The calculation method is: ； ； Where, is the transformation matrix from the body axis coordinate system to the NED coordinate system. The components of the ground force F in the NED coordinate system and the body axis coordinate system are and , 、 、 They are The x, y, and z components in the NED coordinate system.

9. The method for rapid ground trimming of a flight simulator according to claim 6, wherein: The position vector of the single tire contact point in the body axis coordinate system is obtained as follows: Assume that the center coordinate of the wheel when the landing gear is naturally extended is , the tire rolling radius is , the landing gear compression is , for or Then the position vector of a single tire contact point is: ； in, is the dynamic landing gear compression, is the static landing gear compression.

10. The method for rapid ground trimming of a flight simulator according to claim 1, wherein: The method for solving the attitude angle vector of the aircraft and setting it to the flight simulator to complete the ground trim of the flight simulator is as follows: Read runway information, motion status information, aircraft force information, and obtain aircraft attitude angle vector ,in, is the height, is the pitch angle, is the roll angle, is the yaw angle, and sets the iteration parameters, which include weight coefficient vector, learning rate, and termination condition parameters; Calculate the cost function value based on the aircraft attitude angle vector and the weight coefficient vector, , where the weight coefficient vector , the total force vector of the aircraft body axis , the total moment vector of the aircraft body axis ; A gradient vector is calculated based on the aircraft attitude angle vector and the cost function value to obtain a gradient value: ； ； ； ； ； Based on the current aircraft attitude angle vector , the gradient vector , learning rate , iterate the state vector according to the preset threshold as the termination condition, ; The preset thresholds include the cost function change threshold, the gradient threshold and the maximum number of iterations; When the termination condition is met, the optimized aircraft attitude angle vector is obtained and set to the flight simulator. The total force and total moment of the aircraft body axis are zero, and the ground trim of the flight simulator is completed.

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