A method for calculating parameters of linearized model of aircraft landing gear

Abstract

The present invention discloses a method for calculating the parameters of a linearized model of an aircraft landing gear: Step 1, obtaining the structural parameters of the aircraft landing gear buffer and tire; Step 2, constructing a linearized simplified model stiffness and damping calculation model based on the obtained structural parameters of the aircraft landing gear buffer and tire, including: calculating the linearized equivalent buffer stiffness considering the aircraft landing gear buffer principle; calculating the linearized equivalent buffer damping considering the aircraft landing gear buffer principle; calculating the linearized equivalent tire stiffness; calculating the linearized equivalent tire damping; Step 3, performing calculations on different aircraft landing gears to obtain calculation results for different aircraft landing gears. This method can scientifically and accurately calculate the unknown stiffness and damping parameters in the existing aircraft landing gear linearized model; for the dynamic characteristics of bridge structures under complex aircraft loads, this method significantly improves the calculation efficiency compared to refined numerical simulation while ensuring the accuracy of the calculation results.

Description

Technical Field

[0001] The present invention belongs to the technical field of bridge engineering, is used for dynamic performance analysis of aircraft-loaded bridges, including taxiway bridges and runway bridges, and relates to a method for calculating parameters of a linearized model of aircraft landing gear based on the energy equivalence principle. Background Art

[0002] With the continuous growth of civil aviation and general aviation demand in my country, the number of airports continues to increase, and airport expansion and new construction projects are also gradually increasing. While facing huge construction demands, airports also face new challenges: on the one hand, due to the constraints of existing infrastructure and construction land in the surrounding area, the addition of new runways or taxiways must consider the intersection with existing or planned road and rail networks, rivers, pipelines, etc.; on the other hand, due to the limitations of mountainous and coastal terrain, traditional high-fill and land reclamation methods have problems such as large engineering workloads and environmental damage. The use of taxiway bridges and runway bridges is a good solution to these problems. The calculation and evaluation of the dynamic performance of taxiway bridges and runway bridges is crucial, but aircraft loads are 8 to 30 times that of standard vehicles, and the load distribution range is small.

[0003] For numerical simulation of aircraft loads, Ling Daosheng et al. proposed a semi-analytical finite element method suitable for analyzing the dynamic response of mountain airport runways under aircraft moving loads. They derived the corresponding finite element formulas, compiled a finite element analysis program, and verified the correctness of the calculation method and program through examples. Li Yue et al. simulated the cyclic loading process of aircraft wheel loads using a semi-sinusoidal loading curve. Guo Chengchao et al. used a moving band in an Abaqus model to limit the load movement range and wrote code in Fortran, considering loads such as vertical pressure and horizontal shear force to implement aircraft moving load loading. Qi Chunxiang, Liu Li, and Dong Qian all simplified the aircraft into a four-degree-of-freedom planar model for finite element analysis: the vertical motion and longitudinal pitch rotation of the fuselage, the vertical motion of the nose landing gear, and the vertical motion of the main landing gear. With the development of numerical simulation technology, Meng Xianfeng, Raju et al. used ADAMS / VI-Aircraft software to establish a detailed three-dimensional numerical simulation model of the aircraft. Although accurate aircraft models can help reflect the vibration response information of various aircraft components and have broad prospects in aircraft safety analysis, comfort analysis, etc., their modeling is difficult and the computational workload is large, making them unsuitable for bridge impact coefficient research.

[0004] From the above analysis, we can see that many scholars have achieved remarkable results in the areas of aircraft dynamics and landing gear design improvements. However, the aircraft models currently used in related research are simplified plane models that do not consider the dynamic characteristics of the aircraft buffer, or are refined models with large computational complexity. Simplified aircraft dynamic analysis models that consider the principles of landing gear buffers are very rare, so in-depth research is needed.

[0005] Aircraft landing gear bumpers play an important role in cushioning and damping during landing and taxiing. Traditional bumper design and analysis methods typically use nonlinear analysis techniques to determine their stiffness, damping characteristics, and structural response. However, nonlinear models are computationally complex and require a large amount of experimental data, which complicates the design and optimization process. Therefore, it is particularly important to consider the bumper principle and determine the stiffness and damping parameters for existing simplified and efficient linear models. These parameters should be able to quickly calculate the stiffness and damping of simplified dynamic models of different aircraft models while ensuring accuracy. This can then be used for the dynamic analysis of aircraft-loaded bridges and provide guidance for the study of the dynamic characteristics of aircraft-bridge interactions. Summary of the Invention

[0006] The purpose of the present invention is to provide a method for calculating the parameters of a linearized model of an aircraft landing gear, which solves the problem in the prior art that the simplified aircraft model does not fully consider the landing gear buffer principle, resulting in a lack of scientific connection between the model and the landing gear structural parameters.

[0007] In order to realize the above technical solutions adopted by the present invention,

[0008] In a first aspect, the present invention provides a method for calculating parameters of a linearized model of an aircraft landing gear, comprising the following steps:

[0009] Step 1: Obtain the structural parameters of the aircraft landing gear buffer and tire, including: initial pressure P0, buffer effective cross-sectional area A s , the initial volume of the low-pressure chamber V l0 , initial volume of high pressure chamber V h0 , oil density ρ, buffer effective oil pressure area A h , damping hole flow coefficient C d , Main oil hole area A d , Oil return hole area A r , Tire elastic modulus E t , tire vertical width B, tire diameter D, tire vertical deformation δ t , tire material density ρ t and tire thickness h t ;

[0010] Step 2: Based on the structural parameters of the aircraft landing gear buffer and tire obtained in step 1, a linear simplified model stiffness and damping calculation model is constructed, including:

[0011] (1) Calculate the equivalent buffer stiffness considering the linearization principle of the aircraft landing gear buffer:

[0012]

[0013] Where γ is the polytropic process index; P0 is the initial pressure of the high-pressure chamber and the low-pressure chamber; A s is the effective cross-sectional area of ​​the buffer; V l0 is the initial volume of the low-pressure chamber; V h0 is the initial volume of the high-pressure chamber.

[0014] (2) Calculate the equivalent buffer damping considering the linearization principle of the aircraft landing gear buffer:

[0015]

[0016] Where ρ is the oil density; A h C is the effective oil pressure area of ​​the buffer; d is the damping hole flow coefficient; A d Is the main oil hole area; A r is the oil return hole area.

[0017] (3) Calculate the linearized equivalent tire stiffness:

[0018]

[0019] Among them, E t is the elastic modulus of the tire; B is the vertical width of the tire; δ t is the vertical deformation of the tire; D is the tire diameter.

[0020] (4) Calculate the linearized equivalent tire damping:

[0021]

[0022] Where ξ is the damping ratio of the tire material and structure; ρ t is the density of the tire material; h t is the tire thickness;

[0023] Step 3: Calculate the stiffness and damping calculation model of the linearized simplified model constructed in step 2 for different aircraft landing gears to obtain calculation results for the landing gears of different aircraft.

[0024] Furthermore, the effective cross-sectional area A of the buffer s Measured by laser ranging;

[0025] The initial volume V of the low-pressure chamber l0 and the initial volume of the high-pressure chamber V h0 All were measured by water displacement method;

[0026] The vertical deformation of the tire δ t Measured using a displacement sensor or laser distance meter under static or dynamic load.

[0027] Furthermore, the polytropic process index γ is 1.4.

[0028] Furthermore, the damping ratio ξ of the tire material and structure is 0.1 to 0.3.

[0029] In a second aspect, the present invention provides a device for calculating parameters of a linearized model of an aircraft landing gear, comprising the following modules:

[0030] Aircraft landing gear buffer and tire structural parameter acquisition module, used to obtain the structural parameters of the aircraft landing gear buffer and tire, including: initial pressure P0, buffer effective cross-sectional area A s , the initial volume of the low-pressure chamber V l0 , initial volume of high pressure chamber V h0 , oil density ρ, buffer effective oil pressure area A h , damping hole flow coefficient C d , Main oil hole area A d , Oil return hole area A r , Tire elastic modulus E t , tire vertical width B, tire diameter D, tire vertical deformation δ t , tire material density ρ t and tire thickness h t ;

[0031] The calculation model construction module is used to construct a linear simplified model stiffness and damping calculation model based on the aircraft landing gear buffer and tire structural parameters obtained by the aircraft landing gear buffer and tire structural parameter acquisition module, including:

[0032] (1) Calculate the equivalent buffer stiffness considering the linearization principle of the aircraft landing gear buffer:

[0033]

[0034] Where γ is the polytropic process index; P0 is the initial pressure of the high-pressure chamber and the low-pressure chamber; A s is the effective cross-sectional area of ​​the buffer; V l0 is the initial volume of the low-pressure chamber; V h0 is the initial volume of the high-pressure chamber.

[0035] (2) Calculate the equivalent buffer damping considering the linearization principle of the aircraft landing gear buffer:

[0036]

[0037] Where ρ is the oil density; A h C is the effective oil pressure area of ​​the buffer; d is the damping hole flow coefficient; A d Is the main oil hole area; A ris the oil return hole area.

[0038] (3) Calculate the linearized equivalent tire stiffness:

[0039]

[0040] Among them, E t is the elastic modulus of the tire; B is the vertical width of the tire; δ t is the vertical deformation of the tire; D is the tire diameter.

[0041] (4) Calculate the linearized equivalent tire damping:

[0042]

[0043] Where ξ is the damping ratio of the tire material and structure; ρ t is the density of the tire material; h t is the tire thickness;

[0044] The calculation module calculates different aircraft landing gears according to the linearized simplified model stiffness and damping calculation model constructed by the calculation model construction module, and obtains calculation results of different aircraft landing gears.

[0045] In a third aspect, the present invention provides an electronic device, comprising:

[0046] a memory for storing executable instructions;

[0047] The processor is configured to implement the method for calculating the aircraft landing gear linearization model parameters provided by the first aspect of the present invention when executing the executable instructions or computer program stored in the memory.

[0048] In a fourth aspect, the present invention provides a computer-readable storage medium storing executable instructions or a computer program, characterized in that when the executable instructions are executed by a processor, the method for calculating the aircraft landing gear linearization model parameters provided in the first aspect of the present invention is implemented.

[0049] Compared with the prior art, the present invention has the following beneficial effects:

[0050] Based on the energy equivalence principle, the method of the present invention establishes a relationship between an aircraft linear model that considers the landing gear buffer principle and the internal structural parameters of the landing gear, providing a scientific calculation method for the unknown stiffness and damping parameters of existing aircraft landing gear linearization models. This method can scientifically and accurately calculate the unknown stiffness and damping parameters in existing aircraft landing gear linearization models. For the dynamic characteristics of bridge structures under complex aircraft loads, this method significantly improves computational efficiency compared to refined numerical simulations while ensuring the accuracy of the calculation results. It also establishes a scientific relationship between the unknown stiffness and damping values ​​of existing simplified aircraft models and the structural parameters of the landing gear. BRIEF DESCRIPTION OF THE DRAWINGS

[0051] Figure 1 This is a simplified diagram of an aircraft landing gear model.

[0052] The technical solution of the present invention is further explained below with reference to the accompanying drawings and specific embodiments. DETAILED DESCRIPTION

[0053] like Figure 1 As shown, the calculation method of the aircraft landing gear linearization model parameters provided by the present invention specifically includes the following steps:

[0054] Step 1: Obtain the structural parameters of the aircraft landing gear buffer and tire, including: initial pressure P0, buffer effective cross-sectional area A s , the initial volume of the low-pressure chamber V l0 , initial volume of high pressure chamber V h0 , oil density ρ, buffer effective oil pressure area A h , damping hole flow coefficient C d , Main oil hole area A d , Oil return hole area A r , Tire elastic modulus E t , tire vertical width B, tire diameter D, tire vertical deformation δ t , tire material density ρ t and tire thickness h t .

[0055] The specific ways to obtain these parameters are as follows:

[0056] (1) Initial pressure P0: Many landing gear buffer designs reserve pressure measuring ports on the high-pressure and low-pressure chambers. These pressure measuring ports are generally located on the outer shell of the buffer for easy installation. Through these pressure measuring ports, the pressure sensor can be directly connected to the inside of the cavity to monitor the initial pressure of the high-pressure and low-pressure chambers in real time. If there are no dedicated pressure measuring ports, holes can be drilled on the outer shell of the high-pressure and low-pressure chambers to install the pressure sensor. This installation method requires ensuring that the sensor is in contact with the gas or liquid inside the cavity and maintains good sealing to prevent leakage.

[0057] (2) Buffer effective cross-sectional area A s : Calculation through geometric design of the buffer or measurement using a measuring instrument (such as a laser rangefinder) are both common methods in this field.

[0058] (3) Initial volume V l0 and V h0 : Calculation based on the design drawings of the buffer or direct measurement by the water displacement method are both commonly used methods in this field.

[0059] (4) Oil density ρ: Use a densitometer to measure the oil density under standard conditions. The densitometer can be installed in the oil pipe or oil circuit system connected to the oil reservoir of the oil buffer. This ensures that the densitometer can contact the oil in the buffer in real time during operation. If the system allows, the densitometer can be installed in a bypass pipe. A portion of the oil can be diverted into the bypass by controlling the valve for density measurement, so as not to affect the normal operation of the buffer. For some oil buffers with more complex designs, it is possible to consider reserving a density measurement cavity inside the buffer and using a built-in densitometer for real-time measurement.

[0060] (5) Buffer effective oil pressure area A h : Obtained through conventional calculations combining the structural characteristics and geometric shape of the buffer.

[0061] (6) Damping hole flow coefficient C d : Through fluid dynamics experimental measurements, a flowmeter is used to record the flow rate through the damping orifice. The flowmeter can be installed on the inlet or outlet oil pipe of the damping orifice to directly measure the fluid flow through the damping orifice. This installation method accurately captures flow rate changes, especially the instantaneous flow rate of the oil passing through the damping orifice. If the shock absorber has a dedicated oil return line, the flowmeter can be installed there, as the flow rate in the return line is generally equal to the flow rate through the damping orifice. This avoids installing the flowmeter directly in the high-pressure area, improving the ease and safety of installation.

[0062] (7) Area of ​​main oil hole and oil return hole A d and A r: Calculation based on the pore size and number, or measurement of the geometric parameters of the pores using a microscope are both commonly used methods in this field.

[0063] (8) Tire elastic modulus E t : It can be obtained through material testing, such as using a tensile testing machine to measure the elastic modulus of tire materials.

[0064] (9) Tire vertical width B and diameter D: Measure the tire size directly using precision measuring tools such as calipers.

[0065] (10) Tire vertical deformation δ t : Measure the deformation of the tire under static or dynamic load, using displacement sensors or laser rangefinders.

[0066] (11) Density of tire material ρ t and thickness h t : The density of the tire material is determined by sampling and experiments, and the thickness of the tire is directly measured using a vernier caliper.

[0067] Step 2: Based on the structural parameters of the aircraft landing gear buffer and tire obtained in step 1, a linear simplified model stiffness and damping calculation model is constructed, including:

[0068] (1) Calculate the equivalent buffer stiffness considering the linearization principle of the aircraft landing gear buffer:

[0069]

[0070] Where γ is the polytropic process index, and for adiabatic processes, γ = 1.4. P0 is the initial pressure of the high-pressure chamber and the low-pressure chamber. In the initial reference state of the air spring (i.e., static equilibrium), the initial pressures of the high-pressure chamber and the low-pressure chamber are equal. This is because when the system is in a static state without external load, displacement, or compression, the two chambers are in equilibrium. s is the effective cross-sectional area of ​​the buffer; V l0 is the initial volume of the low-pressure chamber; V h0 is the initial volume of the high-pressure chamber.

[0071] (2) Calculate the equivalent buffer damping considering the linearization principle of the aircraft landing gear buffer:

[0072]

[0073] Where ρ is the oil density; A h C is the effective oil pressure area of ​​the buffer; d is the damping hole flow coefficient; A d Is the main oil hole area; A r is the oil return hole area.

[0074] (3) Calculate the linearized equivalent tire stiffness:

[0075]

[0076] Among them, E t is the elastic modulus of the tire; B is the vertical width of the tire; δ t is the vertical deformation of the tire; D is the tire diameter.

[0077] (4) Calculate the linearized equivalent tire damping:

[0078]

[0079] Where ξ is the damping ratio of the tire material and structure, which is generally 0.1 to 0.3; ρ t is the density of the tire material; h t is the tire thickness.

[0080] The calculation formulas in the above linear simplified model stiffness and damping calculation model are obtained based on the following analysis:

[0081] 1. Construction of nonlinear model and calculation of air spring stiffness:

[0082] (1) For the aircraft landing gear structure, the buffer force can be divided into the air spring force F as and oil damping force F d Two parts, namely: F ci =F as +F d

[0083] (2) The air spring force F mentioned in (1) as It can be calculated using the following formula:

[0084] Where, P0 is the initial pressure of the high-pressure chamber and the low-pressure chamber; V l0 is the initial volume of the low-pressure chamber; V h0 is the initial volume of the high-pressure chamber; A s is the effective cross-sectional area of ​​the buffer; γ is the polytropic process index, and for the adiabatic process, γ = 1.4.

[0085] (3) Nonlinear stiffness k of the air spring in the buffer as is the air spring force F as The displacement y of the buffer relative to the fuselage i -y M The first-order derivative of is expressed as

[0086]

[0087] 2. Linearization process of air spring stiffness based on energy equivalence principle:

[0088] (4) Use mathematical analysis to linearize the complex nonlinear equations. According to the energy equivalence principle, the linearized spring stiffness k as,linear and nonlinear air spring stiffness have the same elastic energy at the same displacement amplitude.

[0089] (5) Air spring force F mentioned in (1) above as The nonlinear elastic energy generated is

[0090]

[0091] (6) Stiffness k after linearization as,linear The elastic energy generated is

[0092]

[0093] (7) According to the energy equivalence principle described in (4), (5) and (6) are equal, that is, E linear =E nonlinear For the convenience of calculation, let Δy=y i -y M , and replace F in (2) as Substituting the expression of into (5), we get the following formula:

[0094]

[0095] (8) According to the Tylor expansion in mathematical methods, the nonlinear F as After linearization, we have the following formula:

[0096] Under the initial static equilibrium condition, F in the above formula as (0)=0

[0097] Therefore, F as It can be approximated by the linear stiffness and displacement y of the buffer relative to the fuselage i -y M The product of

[0098]

[0099] (9) The linear stiffness k can be inversely calculated from the last equation in (8) as,linear for:

[0100]

[0101] (10) Put F in (2) asSubstituting the expression into (9) we can get:

[0102] Combining like terms, the air spring stiffness can be calculated using the following formula:

[0103]

[0104] Among them, k ci is the linearized stiffness taking into account the damper principle, that is, the linearized stiffness taking into account the influence of the oil and gas inside the damper. i is n / r / l, representing the nose landing gear, left main landing gear, and right main landing gear, respectively.

[0105] 3. Calculation of buffer oil damping

[0106] (11) The oil damping force F mentioned in (1) d By establishing a connection with the buffer's own structural parameters, the following formula can be used for calculation:

[0107]

[0108] Where ΔP is the pressure difference; A h is the effective oil pressure area of ​​the buffer; ρ is the oil density; v p Positive stroke speed; v r A is the reverse stroke speed; d Is the main oil hole area; A r is the oil return hole area.

[0109] (12) According to the basic mechanics of landing gear buffer, the actual flow rate of oil

[0110] (13) Oil damping force F d It can also be expressed as: F d =c d v oil 2 .

[0111] 4. Oil damping linearization based on RMS method

[0112] (14) The nonlinear damping force in (13) is equivalently linearized using another mathematical method besides the equivalent capacity principle, namely the root mean square (RMS) value, which can be expressed as:

[0113]

[0114] (15) Assuming the oil flow rate v oil The average value over a period of time is but

[0115]

[0116] (16) According to the RMS principle mentioned in (14), there exists an equivalent linear damping coefficient c d,eq Make the RMS value of the linear system equal to the RMS value of the nonlinear system.

[0117] (17) According to (16), the equivalent linear system F d,eq =c d,eq v oil , the root mean square value of the system is:

[0118] (18) According to the principle of equal root mean square value,

[0119]

[0120] (19) According to (18), the equivalent damping can be expressed as

[0121]

[0122] (20) Substitute the equivalent damping obtained in (19) into the solution of the equivalent oil damping force,

[0123] (21) The oil damping force can be approximately equal to the product of the equivalent damping and the oil flow rate, that is,

[0124]

[0125] (22) According to (21), and considering the relationship between the construction parameters and the oil damping force in (11), we can obtain:

[0126]

[0127] (23) According to (22), the linear damping considering the buffer principle can be solved as:

[0128]

[0129] 5. Establishment of landing gear tire mechanical relationship and calculation and linearization of tire stiffness and damping

[0130] (24) A similar method is used to obtain the linear stiffness and damping of the buffer mentioned above to establish the relationship between the tire's force stiffness and damping and its internal structural parameters. Assuming that the tire is a torus, its relevant parameters are: mass m t , diameter D, width B, vertical stiffness k ti (i is n / r / l), vertical damping c ti , vertical deformation δ t , deformation speed Elastic modulus E t , ground contact area A t , ground length l t .

[0131] Similarly, the stiffness and damping of the tire can also be linearized. The detailed process will not be repeated here. Finally, we can get:

[0132]

[0133] (25)The damping of the tire can be expressed as:

[0134]

[0135] Where ξ is the damping ratio of the tire material and structure, which is generally 0.1 to 0.3. t =ρ t V t

[0136] Among them, ρ t is the density of the tire material, V t is the volume of the tire. For a simplified model, the tire is approximated as a hollow ring. Among them, h t is the tire thickness;

[0137] Put k in (24) ti and m t Substituting the calculation formula into the original tire stiffness and damping expression, we can get:

[0138]

[0139] 6. Aircraft landing gear buffer and tire linear model integration

[0140] (26) (10), (23), (24), and the last equation in (25) form the mathematical relationship between stiffness, damping, and the basic structural parameters of the landing gear in the simplified mass-stiffness-damping model of the landing gear considering the buffer principle. It can be used for different types of aircraft landing gear systems and to simplify their dynamic performance. The simplified model can then be used for the dynamic characteristics analysis and evaluation of aircraft-loaded bridges.

[0141] Step 3: Calculate the stiffness and damping calculation model of the linearized simplified model constructed in step 2 for different aircraft landing gears to obtain calculation results for the landing gears of different aircraft.

[0142] The results obtained in this step can be used for subsequent dynamic analysis of the bridge under aircraft loads.

[0143] As described above, the method of the present invention linearizes the air spring stiffness and damping using energy equivalent distance. This solution overcomes the following difficulties:

[0144] ① Complexity of nonlinear elastic properties: The nonlinear stiffness characteristics of landing gear air springs are susceptible to multiple influences, including compression, temperature, and gas state. Converting these into linear stiffness parameters requires overcoming their complex nonlinear constitutive relationships. Because the nonlinear characteristics of air springs fluctuate significantly with pressure and volume, simplified mechanical relationships alone are insufficient to meet accuracy requirements.

[0145] ② Difficulty in applying the energy equivalence principle: The application of the energy equivalence principle is usually used in simple mechanical systems, while the energy absorption process of air springs involves the dynamic process of gas expansion and compression, which requires precise modeling of energy changes under different working conditions. In addition, in order to achieve linearization, the energy absorption characteristics of the nonlinear system need to be equivalent to a single linear stiffness coefficient. This conversion process involves complex integration and approximation methods, which is extremely challenging. The stiffness and damping parameters determined by the method of the present invention can meet the requirements of fast calculation of stiffness and damping of simplified dynamic models of different types of aircraft while ensuring accuracy. It can then be used for the dynamic analysis of aircraft-loaded bridges and provide guidance for the study of the dynamic characteristics of aircraft-bridge interactions. Its applications in the dynamic analysis of aircraft-loaded bridges are as follows:

[0146] ① Establish a mass-spring-damper model: Use linearized stiffness and damping parameters to construct a simplified aircraft model, and use the mass-spring-damper system to represent the dynamic characteristics of the aircraft during taxiing.

[0147] This model is used to simulate the effects of moving loads and damping on an aircraft.

[0148] ② Construct a bridge-aircraft coupling system: Combine the finite element model of the aircraft bridge with a simplified aircraft model to form a coupled system. The bridge model should include all structural elements and support boundary conditions to accurately reflect the mechanical properties of the bridge.

[0149] ③ Apply taxiing loads: Dynamic loads based on the aircraft's taxiing speed, direction, and payload are applied during the simulation. By linearizing stiffness and damping parameters, the impact force transmission during taxiing is controlled, simulating the actual dynamic effects of the landing gear on the bridge.

[0150] ④ Calculate the dynamic response of the aircraft bridge: Perform time history analysis to calculate the stress, deformation, and vibration response of the bridge under different taxiing speeds and aircraft weights to evaluate the dynamic performance of the bridge.

Claims

1. A method for calculating parameters of a linearized model of an aircraft landing gear, characterized in that: The specific steps include: Step 1: Obtain the structural parameters of the aircraft landing gear buffer and tire, including: initial pressure P0, buffer effective cross-sectional area A s , the initial volume of the low-pressure chamber V l0 , initial volume of high pressure chamber V h0 , oil density ρ, buffer effective oil pressure area A h , damping hole flow coefficient C d , Main oil hole area A d , Oil return hole area A r , Tire elastic modulus E t , tire vertical width B, tire diameter D, tire vertical deformation δ t , tire material density ρ t and tire thickness h t ; Step 2: Based on the structural parameters of the aircraft landing gear buffer and tire obtained in step 1, a linear simplified model stiffness and damping calculation model is constructed, including: (1) Calculate the equivalent buffer stiffness considering the linearization principle of the aircraft landing gear buffer: Where γ is the polytropic process index; P0 is the initial pressure of the high-pressure chamber and the low-pressure chamber; A s is the effective cross-sectional area of ​​the buffer; V l0 is the initial volume of the low-pressure chamber; V h0 is the initial volume of the high-pressure chamber; (2) Calculate the equivalent buffer damping considering the linearization principle of the aircraft landing gear buffer: Where ρ is the oil density; A h C is the effective oil pressure area of ​​the buffer; d is the damping hole flow coefficient; A d Is the main oil hole area; A r is the oil return hole area; (3) Calculate the linearized equivalent tire stiffness: Among them, E t is the elastic modulus of the tire; B is the vertical width of the tire; δ t is the vertical deformation of the tire; D is the tire diameter; (4) Calculate the linearized equivalent tire damping: Where ξ is the damping ratio of the tire material and structure; ρ t is the density of the tire material; h t is the tire thickness; Step 3: Calculate the stiffness and damping calculation model of the linearized simplified model constructed in step 2 for different aircraft landing gears to obtain calculation results for the landing gears of different aircraft.

2. The method for calculating the parameters of the aircraft landing gear linearization model according to claim 1, wherein: The effective cross-sectional area A of the buffer s Measured by laser ranging; The initial volume V of the low-pressure chamber l0 and the initial volume of the high-pressure chamber V h0 All were measured by water displacement method; The vertical deformation of the tire δ t Measured using a displacement sensor or laser distance meter under static or dynamic load.

3. The method for calculating the parameters of the aircraft landing gear linearization model according to claim 1, wherein: The polytropic process index γ is 1.

4.

4. The method for calculating the parameters of the aircraft landing gear linearization model according to claim 1, wherein: The damping ratio ξ of the tire material and structure is 0.1 to 0.

3.

5. A device for calculating parameters of a linearized model of an aircraft landing gear, characterized in that: Includes the following modules: Aircraft landing gear buffer and tire structural parameter acquisition module, used to obtain the structural parameters of the aircraft landing gear buffer and tire, including: initial pressure P0, buffer effective cross-sectional area A s , the initial volume of the low-pressure chamber V l0 , initial volume of high pressure chamber V h0 , oil density ρ, buffer effective oil pressure area A h , damping hole flow coefficient C d , Main oil hole area A d , Oil return hole area A r , Tire elastic modulus E t , tire vertical width B, tire diameter D, tire vertical deformation δ t , tire material density ρ t and tire thickness h t ; The calculation model construction module is used to construct a linear simplified model stiffness and damping calculation model based on the aircraft landing gear buffer and tire structural parameters obtained by the aircraft landing gear buffer and tire structural parameter acquisition module, including: (1) Calculate the equivalent buffer stiffness considering the linearization principle of the aircraft landing gear buffer: Where γ is the polytropic process index; P0 is the initial pressure of the high-pressure chamber and the low-pressure chamber; A s is the effective cross-sectional area of ​​the buffer; V l0 is the initial volume of the low-pressure chamber; V h0 is the initial volume of the high-pressure chamber; (2) Calculate the equivalent buffer damping considering the linearization principle of the aircraft landing gear buffer: Where ρ is the oil density; A h C is the effective oil pressure area of ​​the buffer; d is the damping hole flow coefficient; A d Is the main oil hole area; A r is the oil return hole area; (3) Calculate the linearized equivalent tire stiffness: Among them, E t is the elastic modulus of the tire; B is the vertical width of the tire; δ t is the vertical deformation of the tire; D is the tire diameter; (4) Calculate the linearized equivalent tire damping: Where ξ is the damping ratio of the tire material and structure; ρ t is the density of the tire material; h t is the tire thickness; The calculation module calculates different aircraft landing gears according to the linearized simplified model stiffness and damping calculation model constructed by the calculation model construction module, and obtains calculation results of different aircraft landing gears.

6. An electronic device, characterized in that: The electronic device comprises: A memory for storing executable instructions; a processor for implementing the method according to any one of claims 1 to 4 when executing the executable instructions or computer programs stored in the memory.

7. A computer-readable storage medium storing executable instructions or a computer program, characterized in that: When the executable instructions are executed by a processor, the method according to any one of claims 1 to 4 is implemented.

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