Aircraft landing gear buffer mechanical model construction method and device, and storage medium

Abstract

The present invention discloses a method, device, and storage medium for constructing a mechanical model for an aircraft landing gear bumper, including: Step S1: Establishing a bumper mechanical model; Step S2: Acquiring nose landing gear drop and extension test data; and Step S3: Using the nose landing gear drop and extension test data, correcting the oil damping force in the bumper mechanical model. The technical solution of the present invention improves the accuracy of the bumper mechanical model.

Description

Technical Field

[0001] The present invention belongs to the technical field of aircraft landing gear buffers, and in particular relates to a method and device, a system, and a storage medium for constructing a mechanical model of an aircraft landing gear buffer. Background Art

[0002] Aircraft landing gear bumpers are key components for absorbing landing shock and taxiing vibrations, and their performance directly impacts aircraft safety. Due to the complex gas-liquid interactions within the bumpers, existing mechanical models of aircraft landing gear bumpers suffer from errors. Summary of the Invention

[0003] The technical problem to be solved by the present invention is to provide a method and device for constructing a mechanical model of an aircraft landing gear buffer, which improves the accuracy of the buffer mechanical model, provides reliable support for landing gear structure optimization and dynamic characteristics analysis, and has important engineering value for improving aircraft safety and comfort.

[0004] To achieve the above object, the present invention adopts the following technical solutions:

[0005] A method for constructing a mechanical model of an aircraft landing gear buffer comprises:

[0006] Step S1, establishing a buffer mechanical model;

[0007] Step S2: Acquire nose landing gear drop test data and extension test data;

[0008] Step S3: using the nose landing gear drop test data and the extension test data to correct the oil damping force in the buffer mechanical model.

[0009] Preferably, the front landing gear drop shock test data and protrusion test data include: front landing gear drop shock test data based on an equivalent mass of 1000kg and a falling speed of 3m / s, and front landing gear protrusion test data with a buffer compression stroke of 280mm under three different equivalent masses.

[0010] Preferably, in step S3, the front landing gear drop test data is used, and the multi-island genetic algorithm is adopted to optimize with the minimum relative error between the simulation data and the test data as the optimization goal, and the relevant parameters of the oil damping force in the buffer compression stroke are corrected; the extension test data is used, and the non-dominated sorting genetic algorithm II is adopted as the multi-objective optimization algorithm, and the relative error between the three sets of simulation data and the test data is minimized as the optimization goal, and the relevant parameters of the oil damping force in the buffer extension stroke are corrected.

[0011] The present invention also provides a device for constructing a mechanical model of an aircraft landing gear buffer, comprising:

[0012] A first processing module is used to establish a buffer mechanical model;

[0013] The second processing module is used to obtain nose landing gear drop test data and extension test data;

[0014] The third processing module is used to modify the oil damping force in the buffer mechanical model by using the front landing gear drop test data and the extension test data.

[0015] Preferably, the front landing gear drop shock test data and protrusion test data include: front landing gear drop shock test data based on an equivalent mass of 1000kg and a falling speed of 3m / s, and front landing gear protrusion test data with a buffer compression stroke of 280mm under three different equivalent masses.

[0016] Preferably, the third processing module uses the front landing gear drop test data and adopts the multi-island genetic algorithm to optimize with the minimum relative error between the simulation data and the test data as the optimization goal, and corrects the relevant parameters of the oil damping force in the buffer compression stroke; uses the protrusion test data and adopts the non-dominated sorting genetic algorithm II as the multi-objective optimization algorithm, and optimizes with the minimum relative error between the three sets of simulation data and the test data as the optimization goal, and corrects the relevant parameters of the oil damping force in the buffer extension stroke.

[0017] The present invention also provides a storage medium, on which a computer program is stored. When the computer program is run, the method for constructing a mechanical model of an aircraft landing gear buffer is executed.

[0018] This paper establishes a shock absorber mechanical model and uses data from nose landing gear drop and extension tests to correct key parameters of the oil damping force. Using the Isight optimization platform, simulation parameters are optimized using a multi-island genetic algorithm (GA) and a non-dominated sorting genetic algorithm II (NSGA-II), ensuring that the error between the dynamic simulation results and the experimental results is within 10%. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are merely embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on the provided drawings without paying any creative work.

[0020] Figure 1 This is a flow chart of a method for constructing a mechanical model of an aircraft landing gear buffer according to an embodiment of the present invention;

[0021] Figure 2 Comparison between drop shock simulation and test curves;

[0022] Figure 3 Comparison of the sudden extension simulation and experimental curves; among them, (a) is the sudden extension model with an equivalent mass of 900KG; (b) is the sudden extension model with an equivalent mass of 1000KG; (c) is the sudden extension model with an equivalent mass of 1100KG. DETAILED DESCRIPTION

[0023] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0024] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the present invention is further described in detail below with reference to the accompanying drawings and specific embodiments.

[0025] Example 1:

[0026] like Figure 1 As shown, an embodiment of the present invention provides a method for constructing a mechanical model of an aircraft landing gear buffer, comprising:

[0027] Step S1, establishing a buffer mechanical model;

[0028] Step S2: Acquire nose landing gear drop test data and nose landing gear extension test data; wherein the nose landing gear drop test data and nose landing gear extension test data include nose landing gear drop test data based on an equivalent mass of 1000 kg and a drop velocity of 3 m / s, and nose landing gear extension test data with a buffer compression stroke of 280 mm at three different equivalent masses;

[0029] Step S3: using the nose landing gear drop test data and the extension test data to correct the oil damping force in the buffer mechanical model.

[0030] As an implementation method of the embodiment of the present invention, in step S1, the aircraft landing gear mechanical model is as follows: Figure 1 As shown, it consists of buffers and tires, which absorb landing impact and taxiing vibration to ensure that the aircraft body bears the load within a safe range.

[0031] During landing gear operation, the shock absorber is compressed by ground impact, causing the piston rod to move upward into the compression stroke. Part of this kinetic energy is converted into air compression energy, while oil flows through the oil hole, creating a damping effect and dissipating energy. After the positive stroke, the piston rod moves downward into the extension stroke. The decompression of the air chamber pushes the oil back, creating damping again and dissipating energy. This repeated cycle reduces shock and vibration.

[0032] Furthermore, the air spring force , oil damping force , friction of piston rod and structural constraints The mechanical model that constitutes the buffer is:

[0033] ;

[0034] 1. Air spring force :

[0035] ;

[0036] in: is the effective compression area of ​​the air cavity; is the initial pressure of the air cavity; is the local atmospheric pressure; is the air cavity compression polytropic index; is the initial volume of the air cavity.

[0037] 2. Oil damping force :

[0038] ;

[0039] in: , They are the effective oil pressure areas of the main and return oil chambers respectively; is the oil density; The oil hole area of ​​the main oil chamber; is the flow area of ​​the oil return hole; , are the flow coefficients of the main and return oil holes respectively.

[0040] 3. Friction :

[0041] Friction accounts for a very small proportion of the buffer's axial force and is not considered in the buffer's mechanical model.

[0042] 4. Structural limiting force :

[0043] Structural limiting force Reflects the limiting force on the buffer at maximum extension and compression:

[0044] ;

[0045] Where: K is the axial stiffness of the buffer; is the initial stroke of the buffer; The maximum stroke of the buffer.

[0046] As an implementation method of the embodiment of the present invention, the oil damping force in step S3 is corrected as follows:

[0047] By making targeted corrections to the oil damping force parameters based on the nose landing gear drop and extension test data, the performance of the buffer mechanical model is optimized to more accurately reflect the actual mechanical properties of the landing gear.

[0048] ;

[0049] in: , They are the effective oil pressure areas of the main and return oil chambers respectively; is the oil density; The oil hole area of ​​the main oil chamber; is the flow area of ​​the oil return hole; , are the flow coefficients of the main and return oil holes respectively. The specific calculation parameters are shown in Table 1.

[0050] Table 1 Calculation parameters of oil damping force

[0051]

[0052] Based on the simulation parameters of the oil damping force, both the main and return oil chambers utilize a variable oil orifice design. The oil flow area varies with the buffer's stroke, with different areas for the forward and reverse strokes. To this end, a parameterized model of the oil orifice areas at different strokes was constructed in Adams and set as an optimization design variable. The design variables for the main and return oil orifice areas at different strokes are shown in Tables 2-5. By integrating Isight with Adams for joint simulation analysis, relevant parameters were modified based on experimental data, further improving model accuracy and optimization effectiveness. The integration files required for Isight integration in Adams include .bat and .cmd files.

[0053] Table 2

[0054]

[0055] Table 3

[0056]

[0057] Table 4

[0058]

[0059] Table 5

[0060]

[0061] The work curve obtained from the drop test can be divided into forward and reverse strokes based on the compression and rebound processes of the buffer. During the forward stroke, the buffer is compressed, with the main oil hole and the return oil hole (in the forward stroke direction) jointly providing damping. By analyzing the forward stroke portion of the work curve, relevant parameters can be corrected and optimized. Regarding the effects of the main and return oil holes in the reverse stroke direction, the extension condition manifests as the landing gear being compressed to a certain degree and then instantly released, causing it to rebound rapidly. Therefore, relevant parameters can be corrected by analyzing the extension velocity curve under the extension condition. To correct the buffer's forward stroke parameters, a multi-island genetic algorithm (GA) was employed, using the areas of the main and return oil holes in the forward stroke as optimization design variables. Iterative optimization was performed with the goal of minimizing the relative error between the experimental and simulated work curves.

[0062] In the process of correcting the buffer's reverse stroke related parameters, the non-dominated sorting genetic algorithm II (NSGA-II) was adopted. The areas of the main oil hole and the oil return hole in the buffer's reverse stroke were used as optimization design variables. The iterative optimization was carried out with the minimum relative error between the experimental and simulated protrusion velocity curves as the optimization goal.

[0063] The optimized design variables are shown in Table 6.

[0064] Table 6

[0065]

[0066] The comparison between the drop shock simulation curve and the test curve obtained after optimization is shown in Figure 2 and Table 7.

[0067] Table 7

[0068]

[0069] The comparison between the optimized protrusion simulation curve and the experimental curve is shown in Figure 3 and Table 8.

[0070] Table 8

[0071]

[0072] Comparing the optimized simulation data with the experimental data revealed that the errors between the simulated and experimental values ​​for the drop model's work and the maximum compression stroke were both within 10%. The error in the maximum extension velocity of the extension model was also kept within 10%. This demonstrates the high accuracy of the established model and provides a solid foundation for subsequent research on the dynamic characteristics and structural optimization of the landing gear.

[0073] Example 2:

[0074] An embodiment of the present invention further provides a device for constructing a mechanical model of an aircraft landing gear buffer, comprising:

[0075] A first processing module is used to establish a buffer mechanical model;

[0076] The second processing module is used to obtain nose landing gear drop test data and extension test data;

[0077] The third processing module is used to modify the oil damping force in the buffer mechanical model by using the front landing gear drop test data and the extension test data.

[0078] As an implementation method of an embodiment of the present invention, the front landing gear drop shock test data and the protrusion test data include: the front landing gear drop shock test data based on an equivalent mass of 1000kg and a falling speed of 3m / s, and the front landing gear protrusion test data with a buffer compression stroke of 280mm under three different equivalent masses.

[0079] As an implementation method of an embodiment of the present invention, the third processing module uses the front landing gear drop test data, adopts the multi-island genetic algorithm to optimize with the minimum relative error between the simulation data and the test data as the optimization goal, and corrects the relevant parameters of the oil damping force in the buffer compression stroke; uses the protrusion test data, adopts the non-dominated sorting genetic algorithm II as the multi-objective optimization algorithm, and optimizes with the minimum relative error between the three sets of simulation data and the test data as the optimization goal, and corrects the relevant parameters of the oil damping force in the buffer extension stroke.

[0080] Example 3:

[0081] An embodiment of the present invention further provides a storage medium having a computer program stored thereon, wherein the computer program executes a method for constructing a mechanical model of an aircraft landing gear buffer when the computer program is run.

[0082] The embodiments described above are merely descriptions of preferred embodiments of the present invention and are not intended to limit the scope of the present invention. Without departing from the spirit of the present invention, various modifications and improvements made to the technical solutions of the present invention by persons skilled in the art should fall within the scope of protection defined by the claims of the present invention.

Claims

1. A method for constructing a mechanical model of an aircraft landing gear buffer, characterized in that: include: Step S1, establishing a buffer mechanical model; Step S2: Acquire nose landing gear drop test data and extension test data; Step S3: using the nose landing gear drop test data and the extension test data to correct the oil damping force in the buffer mechanical model; Nose landing gear drop test data and extension test data include: nose landing gear drop test data based on an equivalent mass of 1000kg and a drop velocity of 3m / s, and nose landing gear extension test data with a buffer compression stroke of 280mm at three different equivalent masses; In step S3, in the process of correcting the parameters related to the positive stroke of the buffer, the multi-island genetic algorithm is used, and the areas of the main oil hole and the return oil hole in the positive stroke of the buffer are used as optimization design variables, and iterative optimization is performed with the minimum relative error between the experimental power curve and the simulated power curve as the optimization goal; in the process of correcting the parameters related to the reverse stroke of the buffer, the non-dominated sorting genetic algorithm II is used, and the areas of the main oil hole and the return oil hole in the reverse stroke of the buffer are used as optimization design variables, and iterative optimization is performed with the minimum relative error between the experimental sudden extension speed curve and the simulated sudden extension speed curve as the optimization goal.

2. A device for constructing a mechanical model of an aircraft landing gear buffer, characterized in that: include: A first processing module is used to establish a buffer mechanical model; The second processing module is used to obtain nose landing gear drop test data and extension test data; The third processing module is used to modify the oil damping force in the buffer mechanical model using the nose landing gear drop test data and the extension test data; Nose landing gear drop test data and extension test data include: nose landing gear drop test data based on an equivalent mass of 1000kg and a drop velocity of 3m / s, and nose landing gear extension test data with a buffer compression stroke of 280mm at three different equivalent masses; In the process of correcting the parameters related to the positive stroke of the buffer, the third processing module adopts a multi-island genetic algorithm, and takes the areas of the main oil hole and the return oil hole in the positive stroke of the buffer as the optimization design variables, and performs iterative optimization with the minimum relative error between the experimental power curve and the simulated power curve as the optimization goal; in the process of correcting the parameters related to the reverse stroke of the buffer, the non-dominated sorting genetic algorithm II is adopted, and takes the areas of the main oil hole and the return oil hole in the reverse stroke of the buffer as the optimization design variables, and performs iterative optimization with the minimum relative error between the experimental sudden extension speed curve and the simulated sudden extension speed curve as the optimization goal.

3. A storage medium, characterized in that: The storage medium stores a computer program, which executes the aircraft landing gear buffer mechanical model construction method according to claim 1 when running.

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