A method for controlling aircraft ground main wheels to coordinate turning and prevent rollover

Abstract

The present invention relates to a method for controlling the coordinated turning of the main wheels of an aircraft on the ground to prevent rollover. The method comprises: obtaining the front wheel steering motion parameters and the main wheel coordinated steering motion parameters of the aircraft in real time; calculating the anti-rollover lever arm; under the optimal force condition of the aircraft landing gear, calculating the instantaneous center point coordinates of the ground turning of different front wheel angles based on the force balance equation and the torque balance equation, and obtaining the relationship between the front wheel angle and the main wheel angle corresponding to the center point coordinates; calculating the rollover moment and the stabilizing moment of different front wheel angles; when the rollover moment and the stabilizing moment are balanced, calculating the front wheel limit angle, fitting the aircraft rollover safety envelope based on the front wheel limit angle; controlling the front wheel angle based on the safety envelope to prevent the aircraft from rolling over. Compared with the prior art, the present invention has the advantages of high accuracy and good versatility.

Description

Technical Field

[0001] The invention relates to the field of aircraft ground turning anti-rollover control, and in particular to an aircraft ground main wheel coordinated turning anti-rollover control method. Background Art

[0002] As the demand for air transportation continues to grow, civil aircraft are also developing towards wide-body aircraft with large carrying capacity. Wide-body aircraft have a large takeoff and landing weight, which puts higher requirements on the layout of the landing gear system and the load-bearing capacity of the runway. Aircraft ground taxiing and turning are the main forms of aircraft ground movement. Modern civil aircraft are required to be able to quickly slide off the runway and turn into the taxiway to reduce the runway occupancy time, improve the airport's operating efficiency, improve the aircraft's ground maneuverability, and ensure the safety of aircraft takeoff and landing.

[0003] When a wide-body aircraft makes a ground turn, the main wheels are steered in coordination with the front wheels to reduce the turning radius and the additional lateral torque on the main landing gear. A faster taxiing speed is used to shorten the runway occupancy time and improve the airport's operating efficiency. However, when the aircraft's turning angle and taxiing speed do not match, it may cause the wheels to roll over, causing the aircraft to overturn, causing the pilot to lose the ability to control the aircraft, and posing a safety threat to passengers and crew members. Current anti-rollover control research does not consider the anti-rollover strategy under the condition of coordinated steering of the front wheels and main wheels, and does not consider the landing gear as a whole tire for calculation. There is a large deviation compared with the actual situation of the aircraft, and the accuracy of anti-rollover control is low. Summary of the invention

[0004] The purpose of the present invention is to provide a method for controlling the coordinated turning of the main wheels of an aircraft on the ground to prevent rollover in order to overcome the defects of the above-mentioned prior art. The method obtains the motion parameters of the aircraft's front wheel steering and the main wheel coordinated steering during the coordinated turning of the main wheels on the ground, calculates the aircraft's anti-rollover lever arms corresponding to different front wheel steering angles, calculates the aircraft's instantaneous center points of ground turning corresponding to different front wheel steering angles under the optimal condition of landing gear force, obtains the relationship between the front wheel steering angle and the main wheel steering angle, calculates the rollover moment and the stabilizing moment during the coordinated turning of the main wheels on the ground; calculates the front wheel limit steering angle at the corresponding taxiing speed by balancing the rollover moment and the stabilizing moment, and finally obtains the aircraft's rollover safety envelope by fitting to perform ground turning anti-rollover control of the aircraft, thereby achieving turning anti-rollover control with high accuracy, wide versatility and good control performance.

[0005] The purpose of the present invention can be achieved by the following technical solutions:

[0006] S1. Acquire the aircraft front wheel steering motion parameters and main wheel coordinated steering motion parameters in real time;

[0007] S2, obtaining the aircraft tire coordinates and the aircraft center of gravity coordinates based on the aircraft front wheel steering motion parameters, the aircraft landing gear layout and the geometric dimensions of the aircraft landing gear, and calculating the anti-rollover lever arm based on the aircraft tire coordinates and the aircraft center of gravity coordinates;

[0008] S3. Under the optimal force condition of the aircraft landing gear, the instantaneous center point coordinates of the ground turn at different front wheel turning angles are calculated based on the force balance equation and the torque balance equation, and the relationship between the front wheel turning angle and the main wheel turning angle corresponding to the center point coordinates is obtained, and the parameters of the force balance equation and the torque balance equation include the aircraft front wheel steering motion parameters and the main wheel coordinated steering motion parameters;

[0009] S4, calculating the rollover moment and the stabilizing moment at different front wheel turning angles according to the relationship between the instantaneous center point coordinates of the ground turn and the front wheel turning angle and the main wheel turning angle;

[0010] S5. When the rollover moment and the stabilizing moment are balanced, the front wheel limit turning angle is calculated, and the aircraft rollover safety envelope is obtained by fitting based on the front wheel limit turning angle, where the safety envelope is a function curve between the front wheel limit turning angle and the aircraft taxiing speed;

[0011] S6. Control the front wheel steering angle based on the aircraft rollover safety envelope to prevent the aircraft from rolling over.

[0012] Furthermore, the optimal force condition of the aircraft landing gear is to satisfy the optimal objective function of the landing gear force, and the function expression is:

[0013] f1=min(|T O |+|T I |)

[0014] f2=|F O -F I |≤F

[0015] f3=||T O |-|T I ||≤T

[0016] Among them, T O is the turning outer main landing gear torque, T I is the main landing gear torque on the inside of the turn, F O is the lateral force of the main landing gear on the outer side of the turn, F I is the lateral force of the main landing gear on the inside of the turn, T is the torque safety difference between the inside and outside main landing gears of the turn, and F is the lateral force safety difference between the inside and outside main landing gears of the turn.

[0017] Furthermore, the calculation expressions of the rollover moment and the stabilizing moment are:

[0018] T1=N CD H

[0019] T2=(GY)S

[0020] Among them, T1 is the rollover moment, T2 is the stabilizing moment, N CD is the projection of the resultant force of the ground on the tire on the CD vertical line, H is the height of the center of gravity of the aircraft, G is the weight of the aircraft, Y is the lift of the aircraft, and S is the anti-rollover lever arm.

[0021] Furthermore, the expression for the balance between the rollover moment and the stabilizing moment is:

[0022] T1=T2

[0023] Among them, T1 is the rollover moment and T2 is the stabilizing moment.

[0024] Furthermore, the specific expression of the projection of the resultant force of the ground on the tire on the CD vertical line is:

[0025] N CD =(F E -F G )sinβ+F n cos(β-θ)

[0026] Among them, F E is the engine thrust, F G is the head-on resistance, F n is the normal inertia force of the aircraft turning, β is the angle between the velocity direction of the aircraft center of gravity and the axis of the fuselage, and θ is the angle between the anti-rollover lever arm and the axis of the fuselage.

[0027] Furthermore, the calculation expression of the anti-rollover lever arm is:

[0028]

[0029] Among them, (x C ,y C ) is the coordinate of point C of the front outer tire of the outer main landing gear of the aircraft, (x D ,y D ) is the coordinate of point D of the outer tire of the front landing gear of the aircraft, (x G ,y G ) is the G coordinate of the aircraft's center of gravity.

[0030] Furthermore, controlling the front wheel turning angle based on the aircraft rollover safety envelope specifically includes: obtaining the current aircraft taxiing speed, and controlling the front wheel turning angle not to exceed the front wheel limit turning angle.

[0031] Furthermore, the front wheel steering motion parameters include the front wheel steering angle, the front wheel sideslip angle and the aircraft taxiing speed.

[0032] Furthermore, the main wheel coordinated steering motion parameters include an inner main wheel turning angle, an outer main wheel turning angle, a sideslip angle of each tire of the main landing gear, and a taxiing speed of the aircraft.

[0033] Furthermore, the sideslip angles of each tire of the main landing gear include the sideslip angle of the front axle main wheel, the sideslip angle of the middle axle main wheel and the sideslip angle of the rear axle main wheel.

[0034] Compared with the prior art, the present invention has the following beneficial effects:

[0035] (1) The invention solves the coordinates of the instantaneous center point of the aircraft ground turning under the optimal landing gear force conditions and obtains the corresponding relationship between the front wheel angle and the main wheel angle, and further calculates the rollover moment and the stability moment to balance them to obtain the front wheel limit angle. The rollover envelope obtained takes into account the influence of the front wheel steering and the main wheel coordinated steering during the aircraft ground turning process, fills the gap in the current theoretical calculation method for the anti-rollover of the main wheel coordinated turning of the aircraft on the ground, and provides a theoretical basis for the design of the anti-rollover control system for multi-wheel and multi-pillar aircraft ground turning.

[0036] (2) The present invention calculates the anti-rollover lever arm during the turning process based on the front landing gear turning angle, the aircraft's overall dimensions, and the position coordinates of a single tire of the landing gear, while taking into account the elasticity of the tire. Compared with calculating the landing gear as a whole tire, the calculation result obtained by this solution is more in line with the actual aircraft scenario, improves the calculation accuracy and versatility, and improves the anti-rollover control performance. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] Figure 1 is a flow chart of the present invention;

[0038] Figure 2 It is a schematic diagram of the plane of the aircraft ground main wheels coordinated turning of the present invention;

[0039] Figure 3 It is a schematic diagram of the layout of the aircraft landing gear tires of the present invention;

[0040] Figure 4 It is a schematic diagram of the aircraft force of the present invention;

[0041] Figure 5 It is the safety envelope diagram of the present invention. DETAILED DESCRIPTION

[0042] The present invention is described in detail below in conjunction with the accompanying drawings and specific embodiments. This embodiment is implemented based on the technical solution of the present invention, and provides a detailed implementation method and specific operation process, but the protection scope of the present invention is not limited to the following embodiments.

[0043] The present invention provides a method for controlling the ground main wheels of an aircraft to coordinate turning and prevent rollover. The flowchart of the method is as follows: Figure 1As shown, the method comprises the following steps:

[0044] S1. During the coordinated turning of the aircraft's main wheels on the ground, the aircraft's front wheel steering motion parameters and the main wheel coordinated steering motion parameters are obtained in real time. The front wheel steering motion parameters include the front wheel steering angle, the front wheel sideslip angle, and the taxiing speed. The main wheel rotation motion parameters include the inner main wheel steering angle, the outer main wheel steering angle, the sideslip angle of each tire of the main landing gear, and the taxiing speed. The sideslip angle of each tire of the main landing gear specifically includes the front axle main wheel sideslip angle, the middle axle main wheel sideslip angle, and the rear axle main wheel sideslip angle.

[0045] S2. Obtain the aircraft tire coordinates and the aircraft center of gravity coordinates based on the aircraft front wheel steering motion parameters, the aircraft landing gear layout and the geometric dimensions of the aircraft landing gear, and calculate the anti-rollover lever arm based on the aircraft tire coordinates and the aircraft center of gravity coordinates. The calculation expression of the anti-rollover lever arm is:

[0046]

[0047] Among them, (x C ,y C ) is the coordinate of point C of the front outer tire of the outer main landing gear of the aircraft, (x D ,y D ) is the coordinate of point D of the outer tire of the front landing gear of the aircraft, (x G ,y G ) is the G coordinate of the aircraft's center of gravity.

[0048] S3. Under the optimal stress condition of the aircraft landing gear, the instantaneous center point coordinates of the ground turn under different front wheel turning angles are calculated based on the force balance equation and the torque balance equation, and the relationship between the front wheel turning angle and the main wheel turning angle corresponding to the center point coordinates is obtained.

[0049] Assuming the coordinates of the center point of the aircraft turning on the ground (x, y), under the conditions of satisfying the force balance and torque balance in the coordinated turning process of the aircraft's main wheels on the ground, and ensuring the optimal force of the landing gear at different aircraft taxiing speeds, the algorithm can be used to optimize the relationship between the coordinates of the center point of the ground turning (x, y) and the front wheel angle and the main wheel angle of the aircraft's main wheels on the ground corresponding to the center point coordinates. The relationship between the coordinates of the center point of the ground turning on the ground (x, y) and the angle corresponds one to one.

[0050] The force balance equation during the coordinated turning of the aircraft's main wheels on the ground is:

[0051]

[0052]

[0053]

[0054]

[0055]

[0056] Where m is the mass of the aircraft, v is the taxiing speed, R is the distance from the center point of the aircraft's ground turn to the center of gravity, (x, y) is the coordinate of the center point of the aircraft's ground turn, N n1 ~N n2 is the lateral force of the two front wheels, N Mf1 ~N Mf4 is the lateral force of the four front axle main wheels, N Mm1 ~N Mm4 is the lateral force of the four central axle main wheels, N Ma1 ~N Ma4 is the lateral force of the four rear axle main wheels, T n1 ~T n2 is the rolling friction of the two front wheels, T Mf1 ~T Mf4 is the rolling friction of the four front axle main wheels, T Mm1 ~T Mm4 is the rolling friction of the four central axle main wheels, T Ma1 ~T Ma4 is the rolling friction of the four rear axle main wheels, are the 2 front wheel slip angles, The four front axle main wheel slip angles are: The side slip angles of the four center axle main wheels are: is the sideslip angle of the four rear axle main wheels, α is the front wheel turning angle, β1 is the main wheel turning angle on the outer side of the turn, and β2 is the main wheel turning angle on the inner side of the turn.

[0057] In the force balance equation, the tire lateral force includes the front wheel lateral force, the front axle main wheel lateral force, the middle axle main wheel lateral force and the rear axle main wheel lateral force. The calculation expression of the tire lateral force is:

[0058] N=(φ′-0.0668φ′ 2 -0.1032φ′ 3 )μ y V′φ′<1.54

[0059] N=1.0063μ y V′φ′≥1.54

[0060]

[0061] Where N is the tire lateral force, μ y is the lateral friction coefficient, V′ is the tire vertical load, φ′ is the dimensionless sideslip angle, is the lateral stiffness, is the tire slip angle.

[0062] In the calculation expression of tire lateral force, the tire slip angle The calculation expression is:

[0063]

[0064] Wherein, (x, y) is the coordinate of the instantaneous center point of the aircraft turning on the ground, i=n1 is the outer tire of the front landing gear turning, i=n2 is the inner tire of the front landing gear turning, i=f1 is the outer tire of the main landing gear front axle turning on the outside of the turning, i=f2 is the inner tire of the main landing gear front axle turning on the outside of the turning, i=f3 is the outer tire of the main landing gear front axle turning on the inside of the turning, i=f4 is the inner tire of the main landing gear front axle turning on the inside of the turning, i=m1 is the outer tire of the main landing gear middle axle turning on the outside of the turning, i=m2 is the outer tire of the main landing gear front axle turning on the outside of the turning The inner tire of the turning center axle of the landing gear, i=m3 is the outer tire of the turning center axle of the main landing gear on the inner side of the turning, i=m4 is the inner tire of the turning center axle of the main landing gear on the inner side of the turning, i=a1 is the outer tire of the turning rear axle of the main landing gear on the outer side of the turning, i=a2 is the inner tire of the turning rear axle of the main landing gear on the outer side of the turning, i=a3 is the outer tire of the turning rear axle of the main landing gear on the inner side of the turning, i=a4 is the inner tire of the turning rear axle of the main landing gear on the inner side of the turning, α is the front wheel turning angle, β1 is the outer main wheel turning angle, and β2 is the inner main wheel turning angle.

[0065] In the calculation expression of tire lateral force, the calculation expression of tire vertical load is:

[0066]

[0067]

[0068]

[0069]

[0070]

[0071]

[0072]

[0073] Where L1 is the distance from the center of gravity of the aircraft to the front axle of the main landing gear, L2 is the distance from the center of gravity of the aircraft to the middle axle of the main landing gear, L3 is the distance from the center of gravity of the aircraft to the rear axle of the main landing gear, L4 is the distance from the center of gravity of the aircraft to the front landing gear, H is the height of the center of gravity of the aircraft, G is the weight of the aircraft, L da The distance of the front center axis of the main landing gear, L df is the distance between the center and rear axles of the main landing gear, μ is the rolling friction coefficient, and h is the distance between the intersection of the main landing gear bracket and the buffer strut.

[0074] The moment balance equation during the coordinated turning of the aircraft's main wheels on the ground is:

[0075]

[0076]

[0077]

[0078]

[0079]

[0080] f5(α)=(T Ma1 sinβ1+T Ma2 sinβ1+T Ma3 sinβ2+T Ma4 sinβ2)L3

[0081]

[0082]

[0083] Where m is the mass of the aircraft, v is the taxiing speed, R is the distance from the center point of the aircraft's ground turn to the center of gravity, (x, y) is the coordinate of the center point of the aircraft's ground turn, N n1 ~N n2 is the lateral force of the two front wheels, N Mf1 ~N Mf4 is the lateral force of the four front axle main wheels, N Mm1 ~N Mm4 is the lateral force of the four central axle main wheels, N Ma1 ~N Ma4 is the lateral force of the four rear axle main wheels, T n1 ~T n2 is the rolling friction of the two front wheels, T Mf1 ~T Mf4 is the rolling friction of the four front axle main wheels, T Mm1 ~T Mm4 is the rolling friction of the four central axle main wheels, T Ma1 ~T Ma4 is the rolling friction of the four rear axle main wheels, are the 2 front wheel slip angles, The four front axle main wheel slip angles are: The side slip angles of the four center axle main wheels are: is the side slip angle of the four rear axle main wheels, α is the front wheel steering angle, dα / dt is the front wheel control rate, β1 is the main wheel steering angle on the outside of the turn, β2 is the main wheel steering angle on the inside of the turn, J is the aircraft moment of inertia, L is the distance from the front main landing gear, e is the front wheel stability distance, L1 is the distance from the center of gravity of the aircraft to the front axle of the main landing gear, L2 is the distance from the center of gravity of the aircraft to the middle axis of the main landing gear, L3 is the distance from the center of gravity of the aircraft to the rear axle of the main landing gear, L4 is the distance from the center of gravity of the aircraft to the front landing gear, L M is the distance between the two main landing gears, L n is the distance between the two tires of the front landing gear, d M 1 / 2 of the main landing gear coaxial tire distance.

[0084] The optimal objective function of landing gear force is:

[0085] f1=min(|T O |+|T I |)

[0086] f2=|F O -F I |≤F

[0087] f3=||T O |-|T I ||≤T

[0088] Where, T O is the turning outer main landing gear torque, T I is the main landing gear torque on the inside of the turn, F O is the lateral force of the main landing gear on the outer side of the turn, F I is the lateral force of the main landing gear on the inside of the turn, T is the torque safety difference between the inside and outside main landing gears of the turn, and F is the lateral force safety difference between the inside and outside main landing gears of the turn.

[0089] S4. According to the relationship between the instantaneous center coordinates of the aircraft's ground turn and the front wheel turning angle and the main wheel turning angle, the rollover moment and the stabilizing moment under different front wheel turning angles are calculated.

[0090] The calculation expressions of rollover moment and stability moment are:

[0091] T1=N CD H

[0092] T2=(GY)S

[0093] When the rollover moment is greater than the stabilizing moment, rollover may occur.

[0094] Among them, T1 is the rollover moment, T2 is the stabilizing moment, N CD is the projection of the resultant force of the ground on the tire on the CD vertical line, H is the height of the center of gravity of the aircraft, G is the weight of the aircraft, Y is the lift of the aircraft, and S is the anti-rollover lever arm.

[0095] N CD The calculation expression is:

[0096] N CD =(F E -F G )sinβ+F n cos(β-θ)

[0097] in,

[0098]

[0099]

[0100]

[0101] In the formula, (x C ,y C ) is the coordinate of point C of the front outer tire of the outer main landing gear of the aircraft, (x D ,y D ) is the coordinate of point D of the outer tire of the front landing gear of the aircraft, (x, y) is the coordinate of the center point of the aircraft turning on the ground, F E is the engine thrust, F G is the head-on resistance, F n is the normal inertia force of the aircraft turning, β is the angle between the velocity direction of the aircraft center of gravity and the axis of the fuselage, and θ is the angle between the anti-rollover lever arm and the axis of the fuselage.

[0102] S5. By balancing the rollover moment and the stabilizing moment, the front wheel limit angle during the coordinated turning of the aircraft's main wheels on the ground is determined, and then the aircraft rollover safety envelope is obtained by fitting. The safety envelope is a function curve between the front wheel limit angle and the aircraft's taxiing speed.

[0103] The condition for the rollover moment and the stabilizing moment to be balanced is:

[0104] N CD H=(GY)S

[0105] S6. According to the aircraft rollover safety envelope, the aircraft ground main wheel coordinated turning anti-rollover control is performed. The current aircraft taxiing speed is obtained, and the front wheel angle is controlled not to exceed the front wheel limit angle to prevent the aircraft from rolling over.

[0106] The following is an example:

[0107] In this example, the plane diagram of the coordinated turning of the aircraft's main wheels on the ground is as follows: Figure 2 The schematic diagram of the aircraft landing gear tire layout is shown in Figure 3 The force diagram of the aircraft is shown in Figure 4 The data in the specific calculation process are shown in Table 1 and Table 2.

[0108] Table 1 Landing gear tire parameters

[0109] Tire position Tire width Tire diameter Tire pressure Nose landing gear 0.4445m 1.0922m 1499400Pa Main landing gear 0.5334m 1.3208m 1499400Pa

[0110] Table 2 Aircraft ground turning parameters

[0111]

[0112]

[0113] The calculated safety envelope is as follows: Figure 5 shown.

[0114] The present invention obtains motion parameters of the aircraft during the coordinated turning of the aircraft's main wheels on the ground; calculates the aircraft's anti-rollover lever arms corresponding to different front wheel turning angles; calculates the instantaneous center point coordinates of the aircraft's ground turning at different front wheel turning angles under the optimal landing gear force condition, and obtains the corresponding front main wheel turning angle relationship; calculates the rollover moment and the stabilizing moment of the aircraft during the ground turning based on the instantaneous center point coordinates; calculates the front wheel's limit turning angle at the corresponding taxiing speed by balancing the rollover moment and the stabilizing moment; and obtains the aircraft's rollover safety envelope by fitting, thereby performing anti-rollover control of the aircraft's ground main wheel coordinated turning. The obtained rollover safety envelope takes into account the effects of front wheel steering and main wheel coordinated steering during the aircraft's ground turning process, filling the gap in the current theoretical calculation method for anti-rollover of main wheel coordinated turning of aircraft on the ground, and providing a theoretical basis for the design of anti-rollover control systems for multi-wheel and multi-pillar aircraft on the ground. The calculation process takes into account the elasticity of the tire and calculates based on a single tire. Compared with treating the landing gear as a whole tire, the obtained aircraft ground turning rollover safety envelope is more in line with the actual rollover scenario of the aircraft, improves the calculation accuracy and versatility, fills the gap in the subsequent results of calculation research based on the instantaneous center point of the aircraft's ground turning, and provides a theoretical basis for improving the maneuverability and safety of the aircraft during ground turning.

[0115] The preferred specific embodiments of the present invention are described in detail above. It should be understood that a person skilled in the art can make many modifications and changes based on the concept of the present invention without creative work. Therefore, any technical solution that can be obtained by a person skilled in the art through logical analysis, reasoning or limited experiments based on the concept of the present invention on the basis of the prior art should be within the scope of protection determined by the claims.

Claims

1. A method for controlling the coordinated turning and rollover prevention of aircraft main wheels on the ground, characterized in that: The following steps are involved: S1. Acquire the aircraft front wheel steering motion parameters and main wheel coordinated steering motion parameters in real time; S2, obtaining the aircraft tire coordinates and the aircraft center of gravity coordinates based on the aircraft front wheel steering motion parameters, the aircraft landing gear layout and the geometric dimensions of the aircraft landing gear, and calculating the anti-rollover lever arm based on the aircraft tire coordinates and the aircraft center of gravity coordinates; S3. Under the optimal force condition of the aircraft landing gear, the instantaneous center point coordinates of the ground turn at different front wheel turning angles are calculated based on the force balance equation and the torque balance equation, and the relationship between the front wheel turning angle and the main wheel turning angle corresponding to the center point coordinates is obtained, and the parameters of the force balance equation and the torque balance equation include the aircraft front wheel steering motion parameters and the main wheel coordinated steering motion parameters; S4, calculating the rollover moment and the stabilizing moment at different front wheel turning angles according to the relationship between the instantaneous center point coordinates of the ground turn and the front wheel turning angle and the main wheel turning angle; S5. When the rollover moment and the stabilizing moment are balanced, the front wheel limit turning angle is calculated, and the aircraft rollover safety envelope is obtained by fitting based on the front wheel limit turning angle, where the safety envelope is a function curve between the front wheel limit turning angle and the aircraft taxiing speed; S6. Control the front wheel turning angle based on the aircraft rollover safety envelope to prevent the aircraft from rolling over. The optimal force condition of the aircraft landing gear is to satisfy the optimal objective function of the landing gear force, and the function expression is: f1=min(|T O |+|T I |); f2=|F O -F I |≤F; f3=||T O |-|T I ||≤T; Among them, T O is the turning outer main landing gear torque, T I is the main landing gear torque on the inside of the turn, F O is the lateral force of the main landing gear on the outer side of the turn, F I is the lateral force of the main landing gear on the inner side of the turn, T is the torque safety difference between the inner and outer main landing gears on the turn, and F is the lateral force safety difference between the inner and outer main landing gears on the turn; the calculation expressions of the rollover moment and the stabilizing moment are: T1=N CD H; T2 = (GY)S; Among them, T1 is the rollover moment, T2 is the stabilizing moment, N CD is the projection of the resultant force of the ground on the tire on the CD vertical line, H is the height of the center of gravity of the aircraft, G is the weight of the aircraft, Y is the lift of the aircraft, S is the anti-rollover lever arm, and the CD vertical line is the perpendicular line between the point C of the front outer tire of the aircraft's outer main landing gear and the point D of the outer tire of the aircraft's front landing gear; The projection N of the resultant force of the ground acting on the tire on the CD vertical line CD The specific expression is: N CD =(F E -F G )sinβ+F n cos(β-θ) Among them, F E is the engine thrust, F G is the head-on resistance, F n is the normal inertia force of the aircraft turning, β is the angle between the velocity direction of the aircraft center of gravity and the axis of the fuselage, and θ is the angle between the anti-rollover lever arm and the axis of the fuselage; The calculation expression of the anti-overturning lever arm is: Among them, (x C ,y C ) is the coordinate of point C of the front outer tire of the outer main landing gear of the aircraft, (x D ,y D ) is the coordinate of point D of the outer tire of the front landing gear of the aircraft, (x G ,y G ) is the G coordinate of the aircraft's center of gravity.

2. The method for controlling the ground main wheels of an aircraft to prevent rollover according to claim 1, characterized in that: The expression for the balance between the rollover moment and the stabilizing moment is: T1=T2.

3. The method for controlling the ground main wheels of an aircraft to prevent rollover according to claim 1, characterized in that: Controlling the front wheel turning angle based on the aircraft rollover safety envelope specifically includes: obtaining the current aircraft taxiing speed, and controlling the front wheel turning angle not to exceed the front wheel limit turning angle.

4. The method for controlling the ground main wheels of an aircraft to prevent rollover by coordinated turning according to claim 1, characterized in that: The front wheel steering motion parameters include the front wheel steering angle, the front wheel sideslip angle and the aircraft taxiing speed.

5. The method for controlling the ground main wheels of an aircraft to prevent rollover according to claim 1, characterized in that: The main wheel coordinated steering motion parameters include the inner main wheel turning angle, the outer main wheel turning angle, the side slip angle of each tire of the main landing gear and the taxiing speed of the aircraft.

6. The method for controlling the ground main wheels of an aircraft to prevent rollover according to claim 5, characterized in that: The sideslip angles of the tires of the main landing gear include the sideslip angles of the main wheels of the front axle, the main wheels of the middle axle and the main wheels of the rear axle.

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