Aircraft tire torsional rigidity test experiment method and system

Abstract

The invention relates to the technical field of experiments, in particular to an experimental method and system for testing the torsional rigidity of an aircraft tire, and is used for testing the yaw torsional rigidity of the aircraft tire under various conditions. The aircraft tire is accelerated to the target rotating speed, and then the vertical load is applied to the aircraft tire through the first oil cylinder. And finally, controlling the second oil cylinder to perform yaw torsion control on the aircraft tire according to the yaw torsion angle curve. And yaw torsion moment is collected in the yaw torsion control process. And finally, the torsional rigidity of the aircraft tire can be calculated through the torsional moment and the yaw torsional angle. According to the invention, different deflection angles can be tested under the conditions of different rotating speeds and loads, so that the corresponding torsional rigidity is obtained. In addition, a dynamic real-time stiffness model calculation method is adopted to apply the load, so that the load control is more accurate, and the safety of the aircraft tire is ensured at the same time.

Description

Technical Field

[0001] The invention relates to the field of experimental technology, in particular to an aviation tire torsional stiffness test method and system. Background Art

[0002] When an airplane is traveling on the ground, the tires will be affected by various factors such as the rotation speed and the load brought by the airplane, resulting in uncertainty in the yaw torsional stiffness of the tires. Therefore, it is necessary to test the yaw torsional stiffness of aircraft tires under different conditions. Finding the torque required for the aircraft tires to rotate at different angles under different conditions is of great significance for the yaw control of aircraft tires. However, in the prior art, there is no technical solution for testing the yaw torsional stiffness of aircraft tires under different conditions. Summary of the invention

[0003] In view of this, an object of the present invention is to provide an aircraft tire torsional stiffness test method and system to solve the problems in the background technology.

[0004] In order to achieve the above object, the present invention adopts the following technical solutions:

[0005] An aircraft tire torsional stiffness test method of the present invention comprises the following steps:

[0006] Accelerating an aircraft tire to a target rotation speed, wherein the aircraft tire is arranged on a wheel frame, the aircraft tire is driven by a drum, and the drum is driven by a motor;

[0007] When the aircraft tire is accelerated to a target speed, a real-time stiffness value of the aircraft tire is calculated based on a dynamic real-time stiffness model, and a target load is applied to the aircraft tire based on the real-time stiffness value of the aircraft tire, wherein the target load is a load in a direction toward the rotating drum applied by a preset first oil cylinder to the wheel frame;

[0008] Controlling a preset second oil cylinder to perform yaw torsion control on the aircraft tire at the target speed and with the target load applied thereto according to a pre-constructed yaw torsion angle curve, and measuring the yaw torsion torque during the yaw torsion control process, wherein the yaw torsion angle curve includes a plurality of time points and the yaw torsion angles corresponding to the plurality of time points;

[0009] The torsional stiffness of the aircraft tire is calculated based on the yaw torsional moment and the yaw torsional angle.

[0010] In one embodiment of the present application, the torsional stiffness K θ The mathematical expression is:

[0011] K θ =T z / α

[0012] Where, T z is the yaw torque, and α is the yaw angle.

[0013] In one embodiment of the present application, the real-time stiffness value of the aircraft tire is calculated based on the dynamic real-time stiffness model, and a target load is applied to the aircraft tire based on the real-time stiffness value of the aircraft tire, including:

[0014] S1, obtaining a load curve, wherein the load curve includes load target values ​​at multiple time points;

[0015] S2, taking the measured stiffness value of the aircraft tire subjected to the load at the previous time point as the initial stiffness value of the aircraft tire at the current time point, and filtering and smoothing the initial stiffness value to obtain the stiffness value at the current time point, wherein the measured stiffness value at the first time point is obtained by actual measurement;

[0016] S3, calculating the displacement at the current time point based on the stiffness value at the current time point and the load target value at the current time point;

[0017] S4, controlling the first oil cylinder to apply a load target value at the current time point to the aircraft tire based on the displacement at the current time point, measuring an actual load value at the current time point, and calculating an actual stiffness value at the current time point based on the actual load value at the current time point and the displacement;

[0018] S5, taking the current time point as the previous time point and the next time point as the current time point, and returning to step S2 until the actually measured load value of the aircraft tire reaches the target load value.

[0019] In one embodiment of the present application, the initial stiffness value S i The mathematical expression is:

[0020]

[0021] Where F' i-1 is the measured load value at the previous time point, D' i-1 is the displacement of the cylinder equipment at the last time point, D zero It is the displacement of the zero position of the first oil cylinder when the load is just applied to the aircraft tire.

[0022] In one embodiment of the present application, the mathematical expression of the displacement at the current time point is:

[0023]

[0024] In the formula, F i is the load target value at the current test time point, C Tis the first adjustment parameter, C f is the second adjustment parameter, is the stiffness value of the aircraft tire at the current time point, D zero It is the displacement of the zero position of the first oil cylinder when the load is just applied to the aircraft tire.

[0025] In one embodiment of the present application, the initial stiffness value is screened and smoothed, including:

[0026] Screening the initial stiffness value at the current test time point based on a pre-constructed dynamic screening range;

[0027] When the initial stiffness value at the current test time point falls within the dynamic screening range, the initial stiffness value at the current test time point is smoothed based on stiffness values ​​at multiple time points before the current test time point to obtain the stiffness value at the current test time point.

[0028] In one embodiment of the present application, the method for constructing the dynamic screening range includes:

[0029] Construct an initial screening range, wherein the lower limit of the initial screening range is The upper limit of the initial screening range is

[0030] In the section where the target load is greater than or equal to the preset load threshold, the operation is executed repeatedly within the target time period. ΔS, until Among them, S Init is the initial stiffness value of the aircraft tire, and n is the number of cycles;

[0031] In the section where the target load is less than the preset load threshold, the operation is executed repeatedly within the target time period. until

[0032] Based on the upper limit value and the lower limit of the change Build dynamic filter ranges.

[0033] In one embodiment of the present application, the initial stiffness value at the current test time point is smoothed based on the stiffness values ​​at multiple time points before the current test time point, including:

[0034] The stiffness value at the current test time point and the stiffness measured values ​​at multiple time points before the current test time point are placed in a set. When the number of elements in the set is less than n', multiple target stiffness value elements are filled at the front of the set so that the number of elements in the set is greater than or equal to n', where n' is the length of performing mean filtering;

[0035] Mean filtering of various lengths is performed on multiple elements in the set to obtain filtering results.

[0036] In one embodiment of the present application, the filtering result The mathematical expression is:

[0037]

[0038] In the formula, S i-n' is the stiffness value at the n'th time point before the current time point, S i-(n'-1) is the stiffness value at the n'-1th time point before the current time point, S i-(n'-2) is the stiffness value at the n'-2th time point before the current time point.

[0039] The present application also provides an aviation tire torsional stiffness test system, comprising:

[0040] An acceleration module, used for accelerating an aircraft tire to a target rotation speed, wherein the aircraft tire is arranged on a wheel frame, the aircraft tire is driven by a drum, and the drum is driven by a motor;

[0041] a load applying module, used for calculating the real-time stiffness value of the aircraft tire based on a dynamic real-time stiffness model when the aircraft tire is accelerated to a target speed, and applying a target load to the aircraft tire based on the real-time stiffness value of the aircraft tire, wherein the target load is a load applied to the wheel frame by a preset first oil cylinder in a direction toward the rotating drum;

[0042] A yaw torsion module is used to control a preset second oil cylinder to perform yaw torsion control on the aircraft tire at the target speed and with the target load applied according to a pre-constructed yaw torsion angle curve, and to measure the yaw torsion torque during the yaw torsion control process, wherein the yaw torsion angle curve includes a plurality of time points and the yaw torsion angles corresponding to the plurality of time points;

[0043] A calculation module is used to calculate the torsional stiffness of the aircraft tire based on the yaw torsional moment and the yaw torsional angle.

[0044] The beneficial effects of the present invention are as follows: an experimental method and system for testing torsional stiffness of an aircraft tire of the present invention, the present application is used to test the yaw torsional stiffness of an aircraft tire under various conditions. First, the aircraft tire is accelerated to a target speed, and then a vertical load is applied to the aircraft tire through a first oil cylinder. Finally, the second oil cylinder is controlled to perform yaw torsion control on the aircraft tire according to a yaw torsion angle curve. The yaw torsion torque is collected during the yaw torsion control process. Finally, the torsional stiffness of the aircraft tire can be calculated by the torsional torque and the yaw torsion angle. The present application can perform tests at different deflection angles under different speeds and loads, thereby obtaining the corresponding torsional stiffness. In addition, the present application uses a dynamic real-time stiffness model calculation method to apply a load, which can ensure that the load control is more accurate while ensuring the safety of the aircraft tire. BRIEF DESCRIPTION OF THE DRAWINGS

[0045] The present invention will be further described below in conjunction with the accompanying drawings and embodiments:

[0046] Figure 1 This is an application scenario diagram of an aircraft tire torsional stiffness test method shown in an embodiment of the present application;

[0047] Figure 2 is a flow chart of an aircraft tire torsional stiffness test method shown in one embodiment of the present application;

[0048] Figure 3 is a schematic diagram of a yaw torsion angle curve in another embodiment of the present application;

[0049] Figure 4 is a schematic diagram of a yaw torsion angle curve in an embodiment of the present application;

[0050] Figure 5 It is a structural diagram of an aircraft tire torsional stiffness test system shown in one embodiment of the present application. DETAILED DESCRIPTION

[0051] The following describes the embodiments of the present invention by specific examples, and those skilled in the art can easily understand other advantages and effects of the present invention from the contents disclosed in this specification. The present invention can also be implemented or applied through other different specific embodiments, and the details in this specification can also be modified or changed in various ways based on different viewpoints and applications without departing from the spirit of the present invention. It should be noted that the following embodiments and features in the embodiments can be combined with each other without conflict.

[0052] It should be noted that the illustrations provided in the following embodiments are only schematic illustrations of the basic concept of the present invention, and thus the drawings only show the layers related to the present invention rather than being drawn according to the number, shape and size of the layers in actual implementation. In actual implementation, the type, quantity and proportion of each layer may be changed arbitrarily, and the layer layout may also be more complicated.

[0053] In the following description, numerous details are discussed to provide a more thorough explanation of embodiments of the present invention; however, it is apparent to one skilled in the art that embodiments of the present invention may be practiced without these specific details.

[0054] Figure 1 FIG. 1 is an application scenario diagram of an aircraft tire torsional stiffness test method shown in an embodiment of the present application, such as Figure 1 As shown, in the present application, a motor 110 is used to drive a rotating drum 120 , and the rotating drum 120 drives an aircraft tire 130 to rotate when rotating.

[0055] The aircraft tire 130 is arranged on the wheel frame. When a load is applied, a vertical force is applied to the wheel frame by using the first oil cylinder 140, so that pressure exists between the aircraft tire 130 and the drum 120, so as to simulate the state of an aircraft walking on the ground.

[0056] When performing deflection control, the second oil cylinder 150 and the transmission device are used to convert the linear motion into rotational motion, thereby driving the wheel frame and the aircraft tire 130 to rotate.

[0057] During the rotation of the aircraft tire 130, the displacement sensor is used to collect the displacement (rotation) of the aircraft tire 130, and the torque sensor is used to collect the rotational torque of the wheel frame. The rotation and rotational torque are returned to the host computer, and the torsional stiffness can be calculated.

[0058] Figure 2 FIG. 1 is a flow chart of a method for testing torsional stiffness of an aircraft tire in one embodiment of the present application. Figure 2 As shown: A method for testing torsional stiffness of an aircraft tire in this embodiment may include steps S210 to S240:

[0059] S210, accelerating the aircraft tire to a target rotation speed;

[0060] S220, when the aircraft tire is accelerated to a target speed, calculating a real-time stiffness value of the aircraft tire based on a dynamic real-time stiffness model, and applying a target load to the aircraft tire based on the real-time stiffness value of the aircraft tire;

[0061] The speed and load control in this application are performed based on pre-built control curves;

[0062] There is an acceleration stage in the speed curve. After reaching the predetermined speed, the curve is in a stable stage. In order to keep the aircraft tire at the predetermined speed, PID closed-loop control can be used.

[0063] When the speed curve reaches the predetermined speed, load control begins. This application uses a dynamic real-time stiffness model calculation method to perform load control, thereby accurately and safely applying the target load. The specific control process is described later.

[0064] S230, controlling a preset second oil cylinder to perform yaw torsion control on the aircraft tire at the target speed and with the target load applied thereto according to a pre-constructed yaw torsion angle curve, and measuring the yaw torsion torque during the yaw torsion control process, wherein the yaw torsion angle curve includes a plurality of time points and yaw torsion angles corresponding to the plurality of time points;

[0065] In this application, the host computer outputs the target yaw curve through a custom parameter setting module, and the host computer sends the load control curve to the controller for storage. Through timestamp consistency, the drum is first rotated to a certain speed, and then the load is applied. When the load and speed reach stable values, yaw control is performed according to the preset curve points.

[0066] S240: Calculate the torsional stiffness of the aircraft tire based on the yaw torsional moment and the yaw torsional angle.

[0067] Figure 3 Schematic diagram of a yaw torsion angle curve in an embodiment of the present application. Figure 3 As shown, the present embodiment adopts the method of manipulating continuous torsion yaw. That is, in the first test, the aircraft tire is rotated to +α, and then changed to -α, and the whole process is a sine curve; in the second test, the aircraft tire is rotated to -α, and then changed to +α, and the whole process is a cosine curve.

[0068] Figure 4 is a schematic diagram of a yaw torsion angle curve in another embodiment of the present application, such as Figure 4 As shown, the present embodiment adopts the method of manipulating continuous torsion yaw. That is, in the first test, the aircraft tire is rotated to +α, maintained for a period of time, and then changed to 0; in the second test, the aircraft tire is rotated to -α, maintained for a period of time, and then changed to 0.

[0069] In the above process, one or more time points are selected to calculate the torsional stiffness, wherein the torsional stiffness K θ The mathematical expression is:

[0070] K θ =T z / α

[0071] Where, Tz is the yaw torque, and α is the yaw angle.

[0072] The above formula can be used to calculate the torsional stiffness at each time point, record it in the table below, and obtain the experimental data.

[0073] Table 1. Experimental data table

[0074]

[0075] The purpose of the rolling tire continuous yaw stiffness test in this application is to measure the tire's heading force, lateral force, torsional moment (steering moment), yaw torsional stiffness and friction coefficient, etc. when turning at a fixed yaw angle at different inflation pressures, different vertical loads and different speeds.

[0076] The mathematical expression of the heading friction coefficient is:

[0077] μ α =F x / F z

[0078] In the formula, μ α is the heading friction coefficient, F x is the ground heading load of the aircraft tire (stable section), F z is the ground vertical load of the aircraft tire (stable segment), α represents the rolling tire yaw angle, the unit is rad.

[0079] In the present application, a 6-component force measuring platform is used to measure the loads in 6 directions of the tire, so that the heading friction coefficient can be conveniently calculated.

[0080] Dynamic real-time stiffness model calculation method

[0081] In this application, there are some inflection points with large changes in the load curve. When applying the load, if the force control method is used, when the load changes greatly, the control opening of the servo valve port is larger. If the tire stability is poor at this time and a tire blowout occurs, the valve port will not be able to change direction in time due to the opening problem, which will cause damage to the equipment. Therefore, in the general direction, this application adopts the displacement control method to avoid damage to the equipment.

[0082] However, during the test, the internal temperature of the tire is constantly changing, and the air pressure is changing accordingly, which causes the stiffness value of the tire to constantly change. Therefore, the relationship between the displacement of the oil cylinder and the load of the tire is constantly changing. Therefore, this application cannot use a fixed stiffness value to conduct the test. Therefore, a dynamic real-time stiffness model calculation method is used for the test.

[0083] In one embodiment of the present application, the real-time stiffness value of the aircraft tire is calculated based on the dynamic real-time stiffness model, and a target load is applied to the aircraft tire based on the real-time stiffness value of the aircraft tire, including:

[0084] S1, obtaining a load curve, wherein the load curve includes load target values ​​at multiple time points;

[0085] S2, taking the measured stiffness value of the aircraft tire subjected to the load at the previous time point as the initial stiffness value of the aircraft tire at the current time point, and filtering and smoothing the initial stiffness value to obtain the stiffness value at the current time point, wherein the measured stiffness value at the first time point is obtained by actual measurement;

[0086] The dynamic real-time stiffness model calculation method adopted in this application, in general, is to use the measured stiffness value of the load test on the aircraft tire at the previous time point as the initial stiffness value of the aircraft tire at the current time point. The overall control idea is to measure and calculate point by point (the refresh cycle can be set), and obtain the next loading point control instruction in real time. The specimen stiffness of this loading point is calculated in real time, and the displacement closed-loop target instruction of the MOOG controller at the next moment is calculated based on this stiffness, the target force value at the next moment, and the measured acceleration value. The target instruction is transmitted to the MOOG controller in real time through the DA output channel of the FPGA.

[0087] The previous time point in this application can be any time point except the last time point. If the previous time point is the first time point, the static stiffness conversion method is used to obtain the stiffness measured value. The static stiffness conversion method is to pre-pressurize the test tire in a static (0 deflection angle) manner so that the load reaches the target load and obtain the relationship between the load and the displacement. Thus, the stiffness measured value of the first time point is obtained.

[0088] Except for the first time point, in subsequent tests, the measured value of the previous time point is used as the initial stiffness value of the current time point, and the initial stiffness value of the current time point is screened, smoothed and calculated to obtain the displacement control value. After displacement control, the measured load and displacement at the current time point are obtained, and then the measured stiffness value at the current time point is obtained, thereby providing the initial stiffness value for the next time point. Repeat the above process to complete the test in a cycle. At the same time, since the tire temperature value between adjacent time points does not change much, the stiffness value is relatively accurate. It will not cause a large test error.

[0089] In one embodiment of the present application, the initial stiffness value S i The mathematical expression is:

[0090]

[0091] Where F' i-1 is the measured load value at the previous time point, D' i-1 is the displacement of the cylinder equipment at the last time point, D zero It is the displacement of the zero position of the first oil cylinder when the load is just applied to the aircraft tire.

[0092] The mathematical expression of the displacement at the current time point is:

[0093]

[0094] In the formula, F i is the load target value at the current time point, C T is the first adjustment parameter, C f is the second adjustment parameter, is the stiffness value of the aircraft tire at the current time point, D zero It is the displacement of the zero position of the first oil cylinder when the load is just applied to the aircraft tire.

[0095] After obtaining the initial stiffness value, there is a certain possibility that the test data at the previous time point was interfered by noise, and the stiffness with a large error was calculated, which would result in a large displacement control value, causing the control to exceed the normal control range and damage the test piece and equipment. Therefore, this application sets a screening range to screen the initial stiffness value.

[0096] In addition, in order to further ensure smooth changes in stiffness, the present application also performs smoothing processing.

[0097] In one embodiment of the present application, the initial stiffness value is screened and smoothed, including:

[0098] (1) screening the initial stiffness value at the current time point based on a pre-constructed dynamic screening range;

[0099] (2) When the initial stiffness value at the current time point falls within the dynamic screening range, the initial stiffness value at the current time point is smoothed based on stiffness values ​​at multiple time points before the current time point to obtain the stiffness value at the current time point.

[0100] In order to prevent the load from fluctuating greatly due to the tire not bearing a certain load in the early stage during load control, which affects the control effect, the range of the actual stiffness value will be considered in the early stage of the load control, and the allowable range of the stiffness can be increased when the load is large. That is, this application constructs a dynamic screening range to screen the initial stiffness value. If it is the initial stiffness value at the beginning of the test, the screening range is small to avoid stiffness with large errors. As the test proceeds, the load on the tire is large. Since the stiffness base value is large at this time, there will not be a large stiffness error. At this time, the screening range is gradually relaxed to improve the test efficiency.

[0101] The method for constructing the dynamic screening range includes:

[0102] Construct an initial screening range, wherein the lower limit of the initial screening range is The upper limit of the initial screening range is

[0103] In the section where the target load is greater than or equal to the preset load threshold, the operation is executed repeatedly within the target time period. ΔS, until Among them, S Init is the initial stiffness value of the aircraft tire, and n is the number of cycles;

[0104] In the section where the target load is less than the preset load threshold, the operation is executed repeatedly within the target time period. until

[0105] Based on the upper limit value and the lower limit of the change Build dynamic filter ranges.

[0106] In this application, the main thing to prevent is the very small stiffness value in the early stage, which will cause the displacement of the cylinder output shaft to be huge and directly damage the tire. Therefore, the lower limit of the dynamic screening range is increased in the early stage. For example, the early screening range is (1,10), and then it can be gradually adjusted to (0.3,10) as the test progresses.

[0107] The change of the stiffness range value should be continuous and no sudden change should occur, so the change of the stiffness range value is divided into n levels and gradually changes to the target value in the timing loop.

[0108] After the dynamic screening range is obtained, the initial stiffness value at the current time point is screened based on the pre-built dynamic screening range;

[0109] When the initial stiffness value at the current time point falls within the dynamic screening range, the initial stiffness value at the current time point is smoothed based on stiffness values ​​at multiple time points before the current time point to obtain the stiffness value at the current time point.

[0110] Among them, if It is determined that the initial stiffness value at the current time point falls within the dynamic screening range, and the initial stiffness value at this time is valid.

[0111] Since the stiffness value calculated by load and displacement has certain noise interference, it will form a stiffness value that fluctuates up and down. If this value is used for control, the D displacement control obtained by the stiffness value formula of load and displacement, D=F / S, will fluctuate up and down, which will amplify the fluctuating load and the fluctuating stiffness value again, causing jitter divergence and ultimately uncontrollable. Therefore, it is necessary to filter the stiffness value to obtain a smooth stiffness curve. Therefore, in this application, after screening, it is also necessary to smooth the initial stiffness value at the current time point based on the stiffness values ​​at multiple time points before the current time point, specifically including:

[0112] (1) The stiffness value at the current time point and the stiffness measured values ​​at multiple time points before the current time point are placed in a set. The mathematical expression of the set is: S = {S' i-(n-1) ,S' i-(n-2) …S' i}

[0113] The smoothing method implemented in the present application is mean filtering, which requires a sufficient number of stiffness measured values. Therefore, if the number of elements in the set is less than n', it is not enough to complete the corresponding mean filtering. The present application fills a plurality of target stiffness value elements at the front of the set, for example, fills a plurality of elements whose stiffness measured value is 1, so that the number of elements in the set is greater than or equal to n', where n' is the length of performing mean filtering;

[0114] (2) Perform mean filtering on multiple elements in the set to obtain a filtering result, where the mathematical expression of mean filtering is:

[0115]

[0116] In the formula, is the mean filtering result;

[0117] In this application, three lengths of mean filtering can be used, namely n'=2, n'=10 and n'=25; therefore, the result of mean filtering is

[0118] S3, calculating the displacement at the current time point based on the stiffness value at the current time point and the load target value at the current time point;

[0119] S4, controlling the first oil cylinder to apply a load target value at the current time point to the aircraft tire based on the displacement at the current time point, measuring an actual load value at the current time point, and calculating an actual stiffness value at the current time point based on the actual load value at the current time point and the displacement;

[0120] S5, taking the current time point as the previous time point and the next time point as the current time point, and returning to step S2 until the actually measured load value of the aircraft tire reaches the target load value.

[0121] The present invention discloses an experimental method for testing torsional stiffness of an aircraft tire. The present application is used to test the yaw torsional stiffness of an aircraft tire under various conditions. First, the aircraft tire is accelerated to a target speed, and then a vertical load is applied to the aircraft tire through a first oil cylinder. Finally, the second oil cylinder is controlled to perform yaw torsion control on the aircraft tire according to a yaw torsion angle curve. The yaw torsion moment is collected during the yaw torsion control process. Finally, the torsional stiffness of the aircraft tire can be calculated by the yaw torsional moment and the yaw torsion angle. The present application can perform tests at different deflection angles under different speeds and loads, thereby obtaining corresponding torsional stiffness. In addition, the present application adopts a dynamic real-time stiffness model calculation method to apply a load, which can ensure that the load control is more accurate while ensuring the safety of the aircraft tire.

[0122] like Figure 5 As shown, the present application also provides an aviation tire torsional stiffness test system, comprising:

[0123] An acceleration module, used for accelerating an aircraft tire to a target rotation speed, wherein the aircraft tire is arranged on a wheel frame, the aircraft tire is driven by a drum, and the drum is driven by a motor;

[0124] a load applying module, used for calculating the real-time stiffness value of the aircraft tire based on a dynamic real-time stiffness model when the aircraft tire is accelerated to a target speed, and applying a target load to the aircraft tire based on the real-time stiffness value of the aircraft tire, wherein the target load is a load applied to the wheel frame by a preset first oil cylinder in a direction toward the rotating drum;

[0125] A yaw torsion module is used to control a preset second oil cylinder to perform yaw torsion control on the aircraft tire at the target speed and with the target load applied according to a pre-constructed yaw torsion angle curve, and to measure the yaw torsion torque during the yaw torsion control process, wherein the yaw torsion angle curve includes a plurality of time points and the yaw torsion angles corresponding to the plurality of time points;

[0126] A calculation module is used to calculate the torsional stiffness of the aircraft tire based on the yaw torsional moment and the yaw torsional angle.

[0127] The present invention discloses an experimental method and system for testing torsional stiffness of aircraft tires. The present application is used to test the yaw torsional stiffness of aircraft tires under various conditions. First, the aircraft tire is accelerated to a target speed, and then a vertical load is applied to the aircraft tire through a first oil cylinder. Finally, the second oil cylinder is controlled to perform yaw torsion control on the aircraft tire according to a yaw torsion angle curve. The yaw torsion torque is collected during the yaw torsion control process. Finally, the torsional stiffness of the aircraft tire can be calculated by the yaw torsional torque and the yaw torsion angle. The present application can perform tests at different deflection angles under different speeds and loads, thereby obtaining the corresponding torsional stiffness. In addition, the present application uses a dynamic real-time stiffness model calculation method to apply a load, which can ensure that the load control is more accurate while ensuring the safety of the aircraft tire.

[0128] This embodiment further provides a computer-readable storage medium on which a computer program is stored. When the program is executed by a processor, any one of the methods in this embodiment is implemented, wherein the method is the execution logic of this system.

[0129] This embodiment also provides an electronic terminal, including: a processor and a memory;

[0130] The memory is used to store a computer program, and the processor is used to execute the computer program stored in the memory, so that the terminal executes any one of the methods in this embodiment.

[0131] The computer-readable storage medium in this embodiment can be understood by ordinary technicians in this field: all or part of the steps of implementing the above-mentioned method embodiments can be completed by hardware related to the computer program. The aforementioned computer program can be stored in a computer-readable storage medium. When the program is executed, the steps of the above-mentioned method embodiments are executed; and the aforementioned storage medium includes: ROM, RAM, magnetic disk or optical disk and other media that can store program codes.

[0132] The electronic terminal provided in this embodiment includes a processor, a memory, a transceiver and a communication interface. The memory and the communication interface are connected to the processor and the transceiver and complete communication with each other. The memory is used to store computer programs, the communication interface is used to communicate, and the processor and the transceiver are used to run computer programs so that the electronic terminal executes each step of the above method.

[0133] In this embodiment, the memory may include a random access memory (RAM), and may also include a non-volatile memory (non-volatile memory), such as at least one disk memory.

[0134] The above-mentioned processor can be a general-purpose processor, including a central processing unit (CPU), a network processor (NP), etc.; it can also be a digital signal processor (DSP), an application specific integrated circuit (ASIC), a field programmable gate array (FPGA) or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components.

[0135] In the above-mentioned embodiments, although the present invention has been described in conjunction with the specific embodiments of the present invention, many replacements, modifications and variations of these embodiments will be apparent to those of ordinary skill in the art based on the foregoing description. The embodiments of the present invention are intended to cover all such replacements, modifications and variations falling within the broad scope of the appended claims.

[0136] The above embodiments are merely illustrative of the principles and effects of the present invention, and are not intended to limit the present invention. Anyone familiar with the art may modify or alter the above embodiments without departing from the spirit and scope of the present invention. Therefore, all equivalent modifications or alterations made by a person of ordinary skill in the art without departing from the spirit and technical concept disclosed by the present invention shall still be covered by the claims of the present invention.

Claims

1. A method for testing torsional stiffness of aircraft tires, characterized in that: Includes steps: Accelerating an aircraft tire to a target rotation speed, wherein the aircraft tire is arranged on a wheel frame, the aircraft tire is driven by a drum, and the drum is driven by a motor; When the aircraft tire is accelerated to a target speed, a real-time stiffness value of the aircraft tire is calculated based on a dynamic real-time stiffness model, and a target load is applied to the aircraft tire based on the real-time stiffness value of the aircraft tire, wherein the target load is a load in a direction toward the rotating drum applied by a preset first oil cylinder to the wheel frame; Controlling a preset second oil cylinder to perform yaw torsion control on the aircraft tire at the target speed and with the target load applied thereto according to a pre-constructed yaw torsion angle curve, and measuring the yaw torsion torque during the yaw torsion control process, wherein the yaw torsion angle curve includes a plurality of time points and the yaw torsion angles corresponding to the plurality of time points; The torsional stiffness of the aircraft tire is calculated based on the yaw torsional moment and the yaw torsional angle.

2. The method for testing torsional stiffness of aircraft tires according to claim 1, characterized in that: The torsional stiffness K θ The mathematical expression is: K θ =T z / a Where, T z is the yaw torque, and α is the yaw angle.

3. The method for testing torsional stiffness of aircraft tires according to claim 1, characterized in that: Calculating the real-time stiffness value of the aircraft tire based on the dynamic real-time stiffness model, and applying a target load to the aircraft tire based on the real-time stiffness value of the aircraft tire, including: S1, obtaining a load curve, wherein the load curve includes load target values ​​at multiple time points; S2, taking the measured stiffness value of the aircraft tire subjected to the load at the previous time point as the initial stiffness value of the aircraft tire at the current time point, and filtering and smoothing the initial stiffness value to obtain the stiffness value at the current time point, wherein the measured stiffness value at the first time point is obtained by actual measurement; S3, calculating the displacement at the current time point based on the stiffness value at the current time point and the load target value at the current time point; S4, controlling the first oil cylinder to apply a load target value at the current time point to the aircraft tire based on the displacement at the current time point, measuring an actual load value at the current time point, and calculating an actual stiffness value at the current time point based on the actual load value at the current time point and the displacement; S5, taking the current time point as the previous time point and the next time point as the current time point, and returning to step S2 until the actually measured load value of the aircraft tire reaches the target load value.

4. The method for testing torsional stiffness of aircraft tires according to claim 5, characterized in that: The initial stiffness value S i The mathematical expression is: In the formula, F' i-1 is the measured load value at the previous time point, D' i-1 is the displacement of the cylinder equipment at the last time point, D zero It is the displacement of the zero position of the first oil cylinder when the load is just applied to the aircraft tire.

5. The method for testing torsional stiffness of aircraft tires according to claim 3, characterized in that: The mathematical expression of the displacement at the current time point is: In the formula, F i is the load target value at the current test time point, C T is the first adjustment parameter, C f is the second adjustment parameter, is the stiffness value of the aircraft tire at the current time point, D zero It is the displacement of the zero position of the first oil cylinder when the load is just applied to the aircraft tire.

6. The method for testing torsional stiffness of aircraft tires according to claim 3, characterized in that: The initial stiffness value is screened and smoothed, including: Screening the initial stiffness value at the current test time point based on a pre-constructed dynamic screening range; When the initial stiffness value at the current test time point falls within the dynamic screening range, the initial stiffness value at the current test time point is smoothed based on stiffness values ​​at multiple time points before the current test time point to obtain the stiffness value at the current test time point.

7. The method for testing torsional stiffness of aircraft tires according to claim 6, characterized in that: The method for constructing the dynamic screening range includes: Construct an initial screening range, wherein the lower limit of the initial screening range is The upper limit of the initial screening range is In the section where the target load is greater than or equal to the preset load threshold, the operation is executed repeatedly within the target time period. until Among them, S Init is the initial stiffness value of the aircraft tire, and n is the number of cycles; In the section where the target load is less than the preset load threshold, the operation is executed repeatedly within the target time period. until Based on the upper limit value and the lower limit of the change Build dynamic filter ranges.

8. The method for testing torsional stiffness of aircraft tires according to claim 6, characterized in that: The initial stiffness value at the current test time point is smoothed based on stiffness values ​​at multiple time points before the current test time point, including: The stiffness value at the current test time point and the stiffness measured values ​​at multiple time points before the current test time point are placed in a set. When the number of elements in the set is less than n', multiple target stiffness value elements are filled at the front of the set so that the number of elements in the set is greater than or equal to n', where n' is the length of performing mean filtering; Mean filtering of various lengths is performed on multiple elements in the set to obtain filtering results.

9. The method for testing torsional stiffness of aircraft tires according to claim 8, characterized in that: The filtering result The mathematical expression is: In the formula, S i-n' is the stiffness value at the n'th time point before the current time point, S i-(n'-1) is the stiffness value at the n'-1th time point before the current time point, S -(n'-2) is the stiffness value at the n'-2th time point before the current time point.

10. An aircraft tire torsional stiffness test system, characterized in that: include: An acceleration module, used for accelerating an aircraft tire to a target rotation speed, wherein the aircraft tire is arranged on a wheel frame, the aircraft tire is driven by a drum, and the drum is driven by a motor; a load applying module, used for calculating the real-time stiffness value of the aircraft tire based on a dynamic real-time stiffness model when the aircraft tire is accelerated to a target speed, and applying a target load to the aircraft tire based on the real-time stiffness value of the aircraft tire, wherein the target load is a load applied to the wheel frame by a preset first oil cylinder in a direction toward the rotating drum; A yaw torsion module is used to control a preset second oil cylinder to perform yaw torsion control on the aircraft tire at the target speed and with the target load applied according to a pre-constructed yaw torsion angle curve, and to measure the yaw torsion torque during the yaw torsion control process, wherein the yaw torsion angle curve includes a plurality of time points and the yaw torsion angles corresponding to the plurality of time points; A calculation module is used to calculate the torsional stiffness of the aircraft tire based on the yaw torsional moment and the yaw torsional angle.

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