A method, device and system for calculating asymmetric brake load of a twin-fuselage aircraft landing gear
By constructing and solving the mechanical equilibrium equations of a twin-fuselage aircraft during asymmetric braking, the loads on each landing gear were calculated, solving the problem of the inability to accurately calculate the landing gear loads of twin-fuselage aircraft in the existing technology, and realizing an accurate reflection of load distribution.
Patent Information
- Application Number
- CN202610195254.6
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2026-02-11
- Publication Date
- 2026-06-23
AI Technical Summary
Existing technology cannot accurately calculate the load distribution of the landing gear of a twin-fuselage aircraft during asymmetric braking, especially the distribution of vertical load, lateral load and braking drag load.
By constructing the balance equations and related relationships for vertical force, lateral force, roll moment, pitch moment, and yaw moment of a twin-fuselage aircraft during asymmetric braking, and using a computing processor to solve these equations, the loads on each landing gear can be calculated.
It enables accurate calculation of landing gear load during asymmetric braking of twin-fuselage aircraft, truly reflecting the load distribution and overcoming the shortcomings of existing technologies.
Smart Images
Figure CN122263373A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of calculating asymmetric braking loads on aircraft landing gear, and more specifically, to a method, apparatus, and system for calculating asymmetric braking loads on the landing gear of a twin-fuselage aircraft. Background Technology
[0002] Landing gear is a critical load-bearing component of an aircraft, significantly impacting safety during the crucial takeoff and landing phases. Ground load on the landing gear is a vital basis for its strength design; therefore, accurately and reasonably determining the ground load on the landing gear is essential for both the landing gear and the aircraft during the design process.
[0003] Existing military aircraft specifications and civil aircraft airworthiness standards stipulate the load calculation method for asymmetric braking of tricycle aircraft, and the calculation principle is as follows: The lateral load, vertical load, and rolling moment at the aircraft's center of gravity are zero.
[0004] The horizontal inertial force generated at the aircraft's center of gravity is balanced by the braking drag of the main landing gear.
[0005] The yaw moment caused by the braking resistance of the main landing gear is balanced by the lateral loads of the nose landing gear and the non-braking side main landing gear.
[0006] The nose-down moment caused by the braking resistance of the main landing gear increases the vertical load on the nose landing gear and decreases the vertical load on the main landing gear.
[0007] Since twin-fuselage aircraft have an additional nose landing gear compared to tricycle aircraft, which introduces two unknown parameters—vertical load and lateral load—it is impossible to calculate the ground load of each landing gear during asymmetric braking using only the load calculation principles of the aforementioned military aircraft specifications and civil aircraft airworthiness standards. Summary of the Invention
[0008] The purpose of this invention is to overcome the shortcomings of the prior art and provide a method, device and system for calculating asymmetric braking loads on the landing gear of a twin-fuselage aircraft. The calculation process is simple and accurate, and can truly reflect the distribution of vertical load, lateral load and braking drag load of a single landing gear during asymmetric braking of a twin-fuselage aircraft.
[0009] The objective of this invention is achieved through the following solution: A method for calculating asymmetric braking loads on the landing gear of a twin-fuselage aircraft includes the following steps: Step 1: Write the first code program in the computer to construct the vertical force balance equation, lateral force balance equation, roll moment balance equation, pitch moment balance equation, and the relationship between braking drag and vertical load of the right main landing gear, as well as the proportional relationship between lateral force and vertical load of the left and right front landing gears during asymmetric braking of the twin-fuselage aircraft. Step 2: Use the computing processor to run the second code program to solve the equations and relationships constructed in Step 1, and obtain the vertical loads of the left main landing gear, right main landing gear, left front landing gear and right front landing gear during asymmetric braking. Step 3: Based on the vertical load, use the computing processor to run the third code program to obtain the braking drag of the right main landing gear, the lateral load of the left main landing gear, the lateral load of the left front landing gear, and the lateral load of the right front landing gear.
[0010] Furthermore, in step one, the vertical force balance equations for a twin-fuselage aircraft during asymmetric braking are constructed, specifically including the following sub-steps: Construct the following vertical force equilibrium equations: ; in, For normal force, This is the vertical load on the left main landing gear. This represents the vertical load on the right main landing gear. This is the vertical load on the left front landing gear. This is the vertical load on the right front landing gear. The maximum weight of the aircraft. This is the acceleration due to gravity.
[0011] Furthermore, in step one, the lateral force balance equations for a twin-fuselage aircraft during asymmetric braking are constructed, specifically including the following sub-steps: Construct the following lateral force equilibrium equations: ; in, It is a lateral force. For the lateral load of the left main landing gear, This refers to the lateral load on the left front landing gear. This refers to the lateral load on the right front landing gear.
[0012] Furthermore, in step one, the rolling moment balance equation for a twin-fuselage aircraft under asymmetric braking is constructed, which specifically includes the following sub-steps: Construct the following rolling moment balance equation: ; in, For rolling torque, This is the distance between the center of the left main landing gear wheel and the center of the right main landing gear wheel. This is the vertical distance from the aircraft's center of gravity to the point where the main landing gear touches down when the aircraft is stationary. This refers to the lateral load on the left front landing gear. This refers to the lateral load on the right front landing gear. For the lateral load of the left main landing gear, This is the vertical load on the left main landing gear. This represents the vertical load on the right main landing gear. This represents the vertical load on the right front landing gear.
[0013] Furthermore, in step one, the equilibrium equation for the nose-swaying moment of a twin-fuselage aircraft during asymmetric braking is constructed, which specifically includes the following sub-steps: Construct the following equilibrium equation for the oscillating head torque: ; in, For the head swing torque, The heading distance from the aircraft's center of gravity to the point of contact with the nose wheel when the aircraft is stationary. This is the heading distance from the aircraft's center of gravity to the point where the main landing gear touches down when the aircraft is stationary. For the braking resistance of the right main landing gear, For the lateral load of the left main landing gear, This refers to the lateral load on the left front landing gear. This refers to the lateral load on the right front landing gear.
[0014] Furthermore, in step one, the pitching moment balance equations for a twin-fuselage aircraft during asymmetric braking are constructed, specifically including the following sub-steps: Construct the following pitch moment equilibrium equation: ; in, For pitching moment, This is the vertical load on the left main landing gear. This represents the vertical load on the right main landing gear. This is the vertical load on the right front landing gear. This is the vertical load on the left front landing gear. For the braking resistance of the right main landing gear, The heading distance from the aircraft's center of gravity to the point of contact with the nose wheel when the aircraft is stationary. This is the heading distance from the aircraft's center of gravity to the point where the main landing gear touches down when the aircraft is stationary. This refers to the vertical distance between the aircraft's center of gravity and the point where the main landing gear touches down when the aircraft is stationary.
[0015] Furthermore, in step one, the relationship between the braking drag of the right main landing gear and the vertical load during asymmetric braking of a twin-fuselage aircraft is constructed, specifically including the following sub-steps: The following equation is constructed to express the relationship between the braking resistance of the right main landing gear and the vertical load: ; in, This is the coefficient of friction between the tire and the airport runway during braking. For the braking resistance of the right main landing gear, This represents the vertical load on the right main landing gear.
[0016] Furthermore, in step one, the proportional relationship between the lateral forces and vertical loads of the left and right front landing gears during asymmetric braking of a twin-fuselage aircraft is constructed, specifically including the following sub-steps: The following proportional relationship between the lateral force and vertical load of the left and right front landing gears is constructed: ; in, This is the vertical load on the right front landing gear. This is the vertical load on the left front landing gear. This refers to the lateral load on the left front landing gear. This refers to the lateral load on the right front landing gear.
[0017] A device for calculating asymmetric brake loads on the landing gear of a twin-fuselage aircraft includes a processor and a memory, wherein the memory stores a computer program that, when loaded by the processor, executes the method described in any of the preceding claims.
[0018] A system for calculating asymmetric brake loads on the landing gear of a twin-fuselage aircraft includes the apparatus described above.
[0019] The beneficial effects of this invention include: This invention considers two parameters: vertical load and lateral load. Based on the principle of dynamic mechanical equilibrium, a mechanical model of the landing gear of a twin-fuselage aircraft under asymmetric braking is constructed. By solving the equilibrium equations, the landing gear load of a twin-fuselage aircraft under asymmetric braking can be calculated. The calculation principle is clear, the calculation results are accurate, and it can truly reflect the distribution of vertical load, lateral load, and braking drag load of a single landing gear under asymmetric braking of a twin-fuselage aircraft. This solves the technical problem that existing aircraft landing gear load calculation methods cannot accurately calculate the asymmetric braking load of twin-fuselage aircraft landing gear. Attached Figure Description
[0020] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. 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.
[0021] Figure 1 This is a flowchart illustrating the main steps of the method in an embodiment of the present invention; Figure 2 An isometric view of an asymmetric braking force analysis of the landing gear of a twin-fuselage aircraft. Figure 3 This is a side view of an asymmetric braking force analysis of the landing gear of a twin-fuselage aircraft. Detailed Implementation
[0022] All features disclosed in all embodiments of this specification, or steps in all methods or processes implied in the disclosure, may be combined and / or extended or replaced in any way, except for mutually exclusive features and / or steps.
[0023] The specific implementation process of this invention is as follows: In a preferred embodiment, such as Figure 1 , Figure 2 and Figure 3 As shown, the present invention specifically provides a method for calculating asymmetric braking loads on the landing gear of a twin-fuselage aircraft, comprising the following steps: Step 1: Write the first code program in the computer to construct the vertical force balance equation, lateral force balance equation, roll moment balance equation, pitch moment balance equation, and the relationship between braking drag and vertical load of the right main landing gear, as well as the proportional relationship between lateral force and vertical load of the left and right front landing gears during asymmetric braking of the twin-fuselage aircraft. Step 2: Use the computing processor to run the second code program to solve the equations and relationships constructed in Step 1, and obtain the vertical loads of the left main landing gear, right main landing gear, left front landing gear and right front landing gear during asymmetric braking. Step 3: Based on the vertical load, use the computing processor to run the third code program to obtain the braking drag of the right main landing gear, the lateral load of the left main landing gear, the lateral load of the left front landing gear, and the lateral load of the right front landing gear.
[0024] It should be noted that the sub-steps in step one that construct the equilibrium equations and relationships can be executed in any order.
[0025] In other embodiments, based on the above embodiments, a method for calculating asymmetric brake loads on the landing gear of a twin-fuselage aircraft is further provided, including the following steps: Step S1: Construct the vertical force balance equations for the twin-fuselage aircraft during asymmetric braking: ; in, Normal force (unit: Newton). Vertical load on the left main landing gear (unit: Newtons). Vertical load on the right main landing gear (unit: Newtons). The vertical load on the left front landing gear is expressed in Newtons. Vertical load on the right front landing gear (unit: Newtons). Maximum weight of the aircraft (unit: kilograms). This is the acceleration due to gravity.
[0026] Step S2: Construct the lateral force balance equations for the twin-fuselage aircraft during asymmetric braking: ; in, Lateral force (unit: Newtons). The lateral load on the left main landing gear is expressed in Newtons. The lateral load on the left front landing gear (unit: Newtons). The lateral load on the right front landing gear (unit: Newtons).
[0027] Step S3: Construct the rolling moment balance equation for the twin-fuselage aircraft during asymmetric braking: ; in Rolling torque (unit: Newton-meter). This is the distance between the center of the left main landing gear wheel and the center of the right main landing gear wheel (unit: meters). The vertical distance (in meters) from the center of gravity of the aircraft to the point of contact with the main landing gear when the aircraft is stationary.
[0028] Step S4: Construct the equilibrium equation for the nose-swaying moment of the twin-fuselage aircraft during asymmetric braking: ; in, The oscillation torque is expressed in Newton-meters (Nm). The heading distance (in meters) from the aircraft's center of gravity to the point of contact with the nose wheel when the aircraft is stationary. The heading distance (in meters) from the center of gravity of the aircraft to the point of contact with the main landing gear when the aircraft is stationary. Braking resistance of the right main landing gear (unit: Newtons).
[0029] Step S5: Construct the pitch moment balance equation for the twin-fuselage aircraft during asymmetric braking: ; in Pitching moment (unit: Newton-meter); Step S6: Construct the relationship between the braking resistance of the right main landing gear and the vertical load during asymmetric braking of the twin-fuselage aircraft: ; in, This is the coefficient of frictional resistance between the tire and the airport runway.
[0030] Step S7: Construct the proportional relationship between the lateral forces and vertical loads of the left and right front landing gears during asymmetric braking of the twin-fuselage aircraft: ; Step S8: Solve the equations from steps S1 to S7 to obtain the vertical load of the left main landing gear during asymmetric braking. The vertical load of the right main landing gear The vertical load of the left front landing gear and the vertical load of the right front landing gear They are respectively: ; Step S9: Calculate the braking resistance of the right main landing gear based on the vertical load obtained in step S8. The lateral load of the left main landing gear The left front landing gear lateral load and the lateral load of the right front landing gear They are respectively: ; In a preferred embodiment, in step S6, the braking friction coefficient between the tire and the airport runway is... The value is 0.8.
[0031] In yet another preferred embodiment of the present invention, based on the method of any of the above embodiments, the maximum weight of the aircraft is... The value is 12000 kg; Take a fixed value of 9.81 m / s 2 ; the yaw distance from the aircraft's center of gravity to the point of contact with the nose wheel The value is 3200mm; the yaw distance from the aircraft's center of gravity to the main landing gear touchdown point. The value is 500mm; the distance between the center of the left main landing gear wheel and the center of the right main landing gear wheel. The value is 5500mm; the vertical distance from the aircraft's center of gravity to the main landing gear touchdown point. The value is 1700mm; the coefficient of friction between the tire and the airport runway. The value is taken as 0.8. The calculated loads on each landing gear of the twin-fuselage aircraft during asymmetric braking are as follows: ; .
[0032] The units described in the embodiments of the present invention can be implemented in software or hardware, and the described units can also be located in a processor. The names of these units do not necessarily limit the specific unit itself.
[0033] According to one aspect of the present invention, a computer program product or computer program is provided, the computer program product or computer program including computer instructions stored in a computer-readable storage medium. A processor of a computer device reads the computer instructions from the computer-readable storage medium, and executes the computer instructions, causing the computer device to perform the methods provided in the various optional implementations described above.
[0034] In another aspect, embodiments of the present invention also provide a computer-readable medium, which may be included in the electronic device described in the above embodiments; or it may exist independently and not assembled into the electronic device. The computer-readable medium carries one or more programs, which, when executed by the electronic device, cause the electronic device to perform the methods described in the above embodiments.
Claims
1. A method for calculating asymmetric braking loads on the landing gear of a twin-fuselage aircraft, characterized in that, Includes the following steps: Step 1: Write the first code program in the computer to construct the vertical force balance equation, lateral force balance equation, roll moment balance equation, pitch moment balance equation, and the relationship between braking drag and vertical load of the right main landing gear, as well as the proportional relationship between lateral force and vertical load of the left and right front landing gears during asymmetric braking of the twin-fuselage aircraft. Step 2: Use the computing processor to run the second code program to solve the equations and relationships constructed in Step 1, and obtain the vertical loads of the left main landing gear, right main landing gear, left front landing gear and right front landing gear during asymmetric braking. Step 3: Based on the vertical load, use the computing processor to run the third code program to obtain the braking drag of the right main landing gear, the lateral load of the left main landing gear, the lateral load of the left front landing gear, and the lateral load of the right front landing gear.
2. The method for calculating asymmetric braking loads on the landing gear of a twin-fuselage aircraft according to claim 1, characterized in that, In step one, the vertical force balance equations for a twin-fuselage aircraft under asymmetric braking are constructed, which specifically includes the following sub-steps: Construct the following vertical force equilibrium equations: ； in, For normal force, This is the vertical load on the left main landing gear. This represents the vertical load on the right main landing gear. This is the vertical load on the left front landing gear. This is the vertical load on the right front landing gear. The maximum weight of the aircraft. This is the acceleration due to gravity.
3. The method for calculating asymmetric braking loads on the landing gear of a twin-fuselage aircraft according to claim 1, characterized in that, In step one, the lateral force balance equations for a twin-fuselage aircraft under asymmetric braking are constructed, which specifically includes the following sub-steps: Construct the following lateral force equilibrium equations: ； in, It is a lateral force. For the lateral load of the left main landing gear, This refers to the lateral load on the left front landing gear. This refers to the lateral load on the right front landing gear.
4. The method for calculating asymmetric braking loads on the landing gear of a twin-fuselage aircraft according to claim 1, characterized in that, In step one, the rolling moment balance equations for a twin-fuselage aircraft under asymmetric braking are constructed, which specifically includes the following sub-steps: Construct the following rolling moment balance equation: ； in, For rolling torque, This is the distance between the center of the left main landing gear wheel and the center of the right main landing gear wheel. This is the vertical distance from the aircraft's center of gravity to the point where the main landing gear touches down when the aircraft is stationary. This refers to the lateral load on the left front landing gear. This refers to the lateral load on the right front landing gear. For the lateral load of the left main landing gear, This is the vertical load on the left main landing gear. This represents the vertical load on the right main landing gear. This represents the vertical load on the right front landing gear.
5. The method for calculating asymmetric braking loads on the landing gear of a twin-fuselage aircraft according to claim 1, characterized in that, In step one, the equilibrium equations for the nose-swaying moment of a twin-fuselage aircraft during asymmetric braking are constructed, which specifically includes the following sub-steps: Construct the following equilibrium equation for the oscillating head torque: ； in, For the head swing torque, The heading distance from the aircraft's center of gravity to the point of contact with the nose wheel when the aircraft is stationary. This is the heading distance from the aircraft's center of gravity to the point where the main landing gear touches down when the aircraft is stationary. For the braking resistance of the right main landing gear, For the lateral load of the left main landing gear, This refers to the lateral load on the left front landing gear. This refers to the lateral load on the right front landing gear.
6. The method for calculating asymmetric braking loads on the landing gear of a twin-fuselage aircraft according to claim 1, characterized in that, In step one, the pitching moment balance equations for a twin-fuselage aircraft under asymmetric braking are constructed, which specifically includes the following sub-steps: Construct the following pitch moment equilibrium equation: ； in, For pitching moment, This is the vertical load on the left main landing gear. This represents the vertical load on the right main landing gear. This is the vertical load on the right front landing gear. This is the vertical load on the left front landing gear. For the braking resistance of the right main landing gear, The heading distance from the aircraft's center of gravity to the point of contact with the nose wheel when the aircraft is stationary. This is the heading distance from the aircraft's center of gravity to the point where the main landing gear touches down when the aircraft is stationary. This refers to the vertical distance between the aircraft's center of gravity and the point where the main landing gear touches down when the aircraft is stationary.
7. The method for calculating asymmetric braking loads on the landing gear of a twin-fuselage aircraft according to claim 1, characterized in that, In step one, the relationship between the braking drag of the right main landing gear and the vertical load during asymmetric braking of a twin-fuselage aircraft is constructed, which specifically includes the following sub-steps: The following equation is constructed to express the relationship between the braking resistance of the right main landing gear and the vertical load: ； in, This is the coefficient of friction between the tire and the airport runway during braking. For the braking resistance of the right main landing gear, This represents the vertical load on the right main landing gear.
8. The method for calculating asymmetric braking loads on the landing gear of a twin-fuselage aircraft according to claim 1, characterized in that, In step one, the proportional relationship between the lateral forces and vertical loads of the left and right front landing gears during asymmetric braking of a twin-fuselage aircraft is constructed, specifically including the following sub-steps: The following proportional relationship between the lateral force and vertical load of the left and right front landing gears is constructed: ； in, This is the vertical load on the right front landing gear. This is the vertical load on the left front landing gear. This refers to the lateral load on the left front landing gear. This refers to the lateral load on the right front landing gear.
9. A device for calculating asymmetric brake loads on the landing gear of a twin-fuselage aircraft, characterized in that, It includes a processor and a memory, wherein the memory stores a computer program that, when loaded by the processor, executes the method as described in any one of claims 1 to 8.
10. A system for calculating asymmetric brake loads on the landing gear of a twin-fuselage aircraft, characterized in that, Includes the apparatus of claim 9.