A Static Tire Lateral Force Zoning Fitting Method and Device

Abstract

The present invention discloses a method and device for fitting the lateral force of a static tire in zones. The method includes: performing a static lateral rigidity test on a test tire to obtain multiple sets of lateral forces and lateral displacements in the load loading stage and the load unloading stage, taking the lateral displacement as the abscissa and the lateral force as the ordinate to draw a scatter plot of the test data of the lateral force and the lateral displacement; dividing the load loading stage and the load unloading stage of the test data scatter plot according to at least two preset load intervals to form multiple zones, and determining the lateral rigidity of each zone according to the lateral force and the lateral displacement of each zone; fitting to generate a lateral rigidity curve according to the lateral rigidity of each zone; wherein, the load of the preset load interval is less than the preset maximum target load, thereby further improving the accuracy of the static tire lateral rigidity result and making it more convenient for tire characteristic analysis.

Description

Technical Field

[0001] The present application relates to the field of tire mechanical property data processing, and more specifically, to a method and device for fitting a static tire lateral force partition. Background Art

[0002] When a tire bears a load and is subjected to a lateral force, the relationship between the lateral force and the lateral displacement is called lateral rigidity. It affects the turning performance of the tire. The greater the lateral rigidity, the better the vehicle turning stability.

[0003] In the national standard, there are two methods for calculating the lateral rigidity of a tire. One is the two-point method, where the lateral rigidity Ky = δFy / δSy = (Fy2–Fy1) / (Sy2–Sy1), Fy2 is the reference lateral force × 30% × 9.8 m / s + 250 N, Fy1 is the reference lateral force × 30% × 9.8 m / s - 250 N, Sy2 is the lateral displacement corresponding to Fy2, and Sy1 is the lateral displacement corresponding to Fy1.

[0004] The other is to extract the lateral force and lateral displacement data segments of 30% - 60% of the vertical force in the lateral force and lateral displacement curve, and perform a unary linear equation fitting using the least squares method according to the formula y = b0 + b1x, and take the slope of the straight line as the lateral rigidity of the tire.

[0005] However, the above two methods only obtain the test data in the vertical force loading stage, without considering the test data in the vertical force unloading stage. The accuracy of the obtained static tire lateral rigidity is relatively low, and the obtained lateral rigidity values are all single-point values, which is not convenient for analyzing the characteristics of the tire.

[0006] Therefore, how to improve the accuracy of the static tire lateral rigidity result and make it more convenient for tire characteristic analysis is a technical problem to be solved at present. Summary of the Invention

[0007] The present invention discloses a method for fitting a static tire lateral force partition to solve the technical problems in the prior art that the accuracy of the static tire lateral rigidity result is low and it is not convenient for tire characteristic analysis. The method includes:

[0008] Assemble the test tire onto the test rim, inflate the test tire to a preset air pressure and park it for a first preset duration;

[0009] Fix the combination of the test tire and the test rim to the test rigid machine and make the test tire contact the contact platform;

[0010] applying a vertical force to the test tire at a first preset moving speed until each preset target load is reached and ultimately reaches a preset maximum target load, wherein after each preset target load or the preset maximum target load is reached and maintained for a second preset time period, applying a lateral force to the contact platform at a second preset moving speed, and determining a lateral displacement when relative slip occurs between the contact platform and the test tire;

[0011] unloading the vertical force from the preset maximum target load to the test tire until it is reduced to each of the preset target loads, wherein after each reduction to the preset target load and maintaining the load for the second preset time, applying a lateral force to the contact platform at the second preset movement speed, and determining a lateral displacement when relative slip occurs between the contact platform and the test tire;

[0012] With the lateral displacement as the abscissa and the lateral force as the ordinate, a scatter plot of the test data of lateral force and lateral displacement is drawn;

[0013] Dividing the load loading phase and the load unloading phase of the test data scatter plot into a plurality of partitions according to at least two preset load intervals, and determining the lateral stiffness of each partition according to the lateral force and lateral displacement of each partition;

[0014] Generate a lateral stiffness curve based on the lateral stiffness fitting of each partition;

[0015] The load in the preset load interval is less than the preset maximum target load.

[0016] In some embodiments of the present application, the lateral rigidity of each partition is determined based on the lateral force and lateral displacement of each partition, specifically:

[0017] Separate cubic polynomial fitting is performed on the lateral force and lateral displacement of each partition, wherein the cubic polynomial fitting formula is y=ax 3 +bx 2 +cx+d, find the values of constants a, b, and c;

[0018] Derivative the cubic polynomial fitting formula to obtain the derivative formula y'=3ax 2 +2bx+c, the lateral stiffness of each partition is determined by substituting the values of constants a, b, and c into the derivative formula;

[0019] Where y is the lateral force, x is the lateral displacement, and y' is the lateral stiffness.

[0020] In some embodiments of the present application, the preset load intervals include 0%-30%, 30%-60% and 60%-90% of the preset maximum target load.

[0021] In some embodiments of the present application, the preset maximum target load includes 80%, or 100%, or 120% of the maximum load of the test tire.

[0022] In some embodiments of the present application, before vertically loading the test tire with a first preset moving speed until each preset target load is reached, the method further includes:

[0023] Vertically loading the test tire with the first preset moving speed until a preliminary test load is reached, unloading after maintaining for a third preset duration, repeating the preset number of times for the preliminary test, and after the preliminary test is completed, inflating the test tire to the preset air pressure.

[0024] Correspondingly, the present invention also provides a static tire lateral force partition fitting device, and the device includes:

[0025] A contact platform that accommodates the test tire and contacts the test tire;

[0026] A loading module for vertically loading the test tire and applying a lateral force to the contact platform;

[0027] A positioning module for determining the lateral displacement when relative slip occurs between the contact platform and the test tire;

[0028] A controller for:

[0029] When receiving a test instruction sent by a user, controlling the loading module to vertically load the test tire with a first preset moving speed until each preset target load is reached and finally reaching the preset maximum target load, wherein, after reaching each of the preset target loads or the preset maximum target load and maintaining for a second preset duration, controlling the loading module to apply a lateral force to the contact platform with a second preset moving speed, and determining the lateral displacement through the positioning module when relative slip occurs between the contact platform and the test tire;

[0030] Controlling the loading module to unload the vertical force of the test tire from the preset maximum target load until it is respectively reduced to each of the preset target loads, wherein, after reducing to each of the preset target loads and maintaining the second preset duration, controlling the loading module to apply a lateral force to the contact platform with the second preset moving speed, and determining the lateral displacement through the positioning module when relative slip occurs between the contact platform and the test tire;

[0031] Taking the lateral displacement as the abscissa and the lateral force as the ordinate, plotting a scatter diagram of the test data of the lateral force and the lateral displacement;

[0032] Dividing the load loading stage and the load unloading stage of the test data scatter diagram according to at least two preset load intervals to form multiple partitions, and determining the lateral rigidity of each partition according to the lateral force and the lateral displacement of each partition.

[0033] Generate a lateral stiffness curve by fitting the lateral stiffness of each partition;

[0034] Among them, the load in the preset load range is less than the preset maximum target load.

[0035] In some embodiments of the present application, the controller is specifically configured to:

[0036] Perform separate cubic polynomial fittings on the lateral force and lateral displacement of each partition. Among them, assume the cubic polynomial fitting formula is y = ax 3 + bx 2 + cx + d, and obtain the numerical values of the constants a, b, and c;

[0037] Take the derivative of the cubic polynomial fitting formula to obtain the derivative formula y' = 3ax 2 + 2bx + c, and substitute the numerical values of the constants a, b, and c into the derivative formula to determine the lateral stiffness of each partition;

[0038] Among them, y is the lateral force, x is the lateral displacement, and y' is the lateral stiffness.

[0039] In some embodiments of the present application, the preset load range includes 0%-30%, 30%-60%, and 60%-90% of the preset maximum target load.

[0040] In some embodiments of the present application, the preset maximum target load includes 80%, or 100%, or 120% of the maximum load of the test tire.

[0041] In some embodiments of the present application, the controller is further configured to:

[0042] When receiving a pre-test instruction sent by the user, control the loading module to load a vertical force on the test tire at the first preset moving speed until the pre-test load is reached, unload after maintaining for a third preset duration, and repeat the preset number of times for pre-test.

[0043] By applying the above technical solutions, perform a static lateral stiffness test on the test tire, obtain multiple groups of lateral forces and lateral displacements in the load loading stage and the load unloading stage, use the lateral displacement as the abscissa and the lateral force as the ordinate to draw a scatter plot of the test data of the lateral force and the lateral displacement; divide the load loading stage and the load unloading stage of the test data scatter plot according to at least two preset load ranges to form multiple partitions, determine the lateral stiffness of each partition according to the lateral force and lateral displacement of each partition; generate a lateral stiffness curve by fitting the lateral stiffness of each partition; among them, the load in the preset load range is less than the preset maximum target load, thereby further improving the accuracy of the static tire lateral stiffness result and making it more convenient for tire characteristic analysis. Description of the Drawings

[0044] To more clearly illustrate the technical solutions in the embodiments of the present application, the following will briefly introduce the accompanying drawings required for the description of the embodiments. Obviously, the accompanying drawings in the following description are only some embodiments of the present application. For those skilled in the art, without creative efforts, other accompanying drawings can also be obtained based on these drawings.

[0045] Figure 1 It shows a schematic flowchart of a static tire lateral force partition fitting method proposed in an embodiment of the present invention;

[0046] Figure 2 It shows a schematic diagram of a tire coordinate system in an embodiment of the present invention;

[0047] Figure 3 It shows a schematic structural diagram of a static tire lateral force partition fitting device proposed in an embodiment of the present invention. Detailed implementation manners

[0048] The following will clearly and completely describe the technical solutions in the embodiments of the present application with reference to the accompanying drawings in the embodiments of the present application. Obviously, the described embodiments are only some embodiments of the present application, rather than all embodiments. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative efforts belong to the scope of protection of the present application.

[0049] The embodiments of the present application provide a static tire lateral force partition fitting method. By processing the test data of the lateral force of each partition, the test data in the load loading stage and the load unloading stage can be accurately fitted into a smooth curve, which is used to calculate tire characteristic values, conduct benchmark analysis, or be used for tire model identification, and has the characteristics of high accuracy, good repeatability, and high efficiency. As Figure 1 shown, it includes the following steps:

[0050] Step S101, assemble the test tire onto the test rim, inflate the test tire to a preset air pressure, and park it until a first preset duration is met.

[0051] In this embodiment, first conduct a tire lateral rigidity test, and determine the final static lateral rigidity result according to the test data.

[0052] Pre-select tires with good appearance quality as test tires, then assemble the test tires onto the test rims, inflate the test tires to a preset air pressure, and park them until a first preset duration is met.

[0053] In some embodiments of the present application, the preset air pressure can be 250 kPa or 290 kPa, and the first preset duration is not less than 24 h. Those skilled in the art can flexibly set different preset air pressures and first preset durations according to actual needs.

[0054] Step S102: Fix the combination of the test tire and the test rim to the test rigid machine, and make the test tire contact the contact platform.

[0055] In this embodiment, the test rigid machine is used to perform a lateral rigidity test on the test tire, and the test tire contacts the contact platform during the test. The contact platform can completely accommodate the part where the entire tire contacts and has sufficient roughness. The contact platform has enough stroke to meet the test requirements. The contact platform and its support structure have sufficient rigidity, and when a vertical force is applied to the tire, the contact platform does not deform laterally, longitudinally, or in terms of bending.

[0056] Step S103: Apply a vertical force to the test tire at a first preset moving speed until each preset target load is reached and finally the preset maximum target load is reached. Among them, after each preset target load or the preset maximum target load is reached and maintained for a second preset duration, apply a lateral force to the contact platform at a second preset moving speed, and determine the lateral displacement when relative slip occurs between the contact platform and the test tire.

[0057] In this embodiment, the directions of the vertical force and the lateral force correspond to the tire coordinate system. As Figure 2 shown, it is a schematic diagram of the tire coordinate system. The vertical force corresponds to the Z'-axis of the tire coordinate system, and the lateral force corresponds to the Y'-axis of the tire coordinate system. The tire coordinate system is a right-handed rectangular coordinate system with the tire contact center as the origin. The X'-axis is the intersection line of the tire center plane and the road plane, and the direction of the tire center plane traveling forward is positive; the Z'-axis is the plumb line, and the upward direction is positive; the Y'-axis is in the road plane, and the direction is determined according to the right-hand rule.

[0058] Multiple preset target loads are preset. Apply a vertical force to the test tire at a first preset moving speed until each preset target load is reached and finally the preset maximum target load is reached. After each preset target load or the preset maximum target load is reached, to improve the test accuracy, maintain the second preset duration, and then apply a lateral force to the contact platform at a second preset moving speed. Determine the lateral displacement when relative slip occurs between the contact platform and the test tire, so as to obtain multiple groups of lateral forces and lateral displacements corresponding to the load loading stage and each preset target load and the preset maximum target load.

[0059] Optionally, the first preset moving speed is 50 mm / min, the second preset duration is 1 min, and the second preset moving speed is 30 mm / min to 50 mm / min. Those skilled in the art can flexibly set different first preset moving speeds, second preset durations, and second preset moving speeds according to actual needs.

[0060] To improve the accuracy of test data, in some embodiments of the present application, before vertically loading the test tire with the first preset moving speed until each preset target load is reached, the method further includes:

[0061] Vertically load the test tire with the first preset moving speed until a preliminary test load is reached, unload after maintaining the third preset duration, repeat the preset number of times for the preliminary test, and after the preliminary test is completed, inflate the test tire to the preset air pressure.

[0062] In this embodiment, before officially performing the lateral rigidity test on the test tire, perform a preset number of preliminary tests. After determining that there is no problem with the test tire and the test rigidity machine, inflate the test tire to the preset air pressure for the official test.

[0063] Optionally, the preliminary test load is 80% of the maximum load of the test tire, and the third preset duration can be 5 s.

[0064] Step S104, unload the vertical force on the test tire from the preset maximum target load until it is reduced to each of the preset target loads respectively. Among them, after each reduction to a preset target load and maintaining the second preset duration, apply a lateral force to the contact platform at the second preset moving speed, and determine the lateral displacement when relative slippage occurs between the contact platform and the test tire.

[0065] In this embodiment, after completing the test in the load loading stage, enter the load unloading stage. Unload the vertical force on the test tire from the preset maximum target load until it is reduced to each preset target load respectively. When each reduction reaches a preset target load, maintain the second preset duration, then apply a lateral force to the contact platform at the second preset moving speed, and determine the lateral displacement when relative slippage occurs between the contact platform and the test tire, so as to obtain multiple groups of lateral forces and lateral displacements corresponding to each preset target load in the load unloading stage.

[0066] Step S105, draw a scatter plot of the test data of the lateral force and the lateral displacement with the lateral displacement as the abscissa and the lateral force as the ordinate.

[0067] In this embodiment, according to the multiple groups of lateral forces and lateral displacements obtained in step S103 and step S104, draw a scatter plot of the test data of the lateral force and the lateral displacement with the lateral displacement as the abscissa and the lateral force as the ordinate.

[0068] Step S106, divide the load application stage and the load unloading stage of the test data scatter plot according to at least two preset load ranges to form multiple partitions, and determine the lateral rigidity of each partition according to the lateral force and lateral displacement of each partition.

[0069] In this embodiment, the load of the preset load range is less than the preset maximum target load. The load application stage of the test data scatter plot is partitioned according to the preset load range, and the load unloading stage of the test data scatter plot is divided according to the preset load range to form multiple partitions, and then the lateral rigidity of each partition is determined according to the test data of each partition.

[0070] Optionally, the preset load ranges in the load application stage and the load unloading stage are the same.

[0071] In order to accurately determine the lateral rigidity of each partition, in some embodiments of the present application, the lateral rigidity of each partition is determined according to the lateral force and lateral displacement of each partition. Specifically:

[0072] Separate cubic polynomial fittings are performed on the lateral force and lateral displacement of each partition. Among them, let the cubic polynomial fitting formula be y = ax 3 + bx 2 + cx + d, and the values of constants a, b, and c are obtained;

[0073] The derivative of the cubic polynomial fitting formula is obtained to get the derivative formula y' = 3ax 2 + 2bx + c, and the lateral rigidity of each partition is determined after substituting the values of constants a, b, and c into the derivative formula;

[0074] Among them, y is the lateral force, x is the lateral displacement, and y' is the lateral rigidity.

[0075] It should be noted that the solutions of the above embodiments are only a specific implementation solution proposed by the present application, and other methods for determining the lateral rigidity of each partition according to the lateral force and lateral displacement of each partition belong to the protection scope of the present application.

[0076] Step S107, fit a lateral rigidity curve according to the lateral rigidity of each partition.

[0077] In this embodiment, a smooth lateral rigidity curve is fitted according to the lateral rigidity of each partition. The lateral rigidity curve can be used to calculate tire characteristic values, conduct benchmark analysis, or be used for tire model identification.

[0078] Optionally, in some embodiments of the present application, the preset load range includes 0% - 30%, 30% - 60%, and 60% - 90% of the preset maximum target load.

[0079] It is understandable that each partition in the load loading stage of the test data scatter plot is divided according to 0%-30%, 30%-60%, and 60%-90% of the preset maximum target load, forming three partitions; each partition in the load unloading stage of the test data scatter plot is also divided according to 0%-30%, 30%-60%, and 60%-90% of the preset maximum target load, forming another three partitions. Therefore, a total of six partitions are formed.

[0080] Optionally, in some embodiments of the present application, the preset maximum target load includes 80%, or 100%, or 120% of the maximum load of the test tire.

[0081] By applying the above technical solution, a static lateral stiffness test is performed on the test tire to obtain multiple sets of lateral forces and lateral displacements in the load loading stage and the load unloading stage. Using the lateral displacement as the abscissa and the lateral force as the ordinate, a test data scatter plot of the lateral force and the lateral displacement is drawn; at least two preset load intervals are used to divide the load loading stage and the load unloading stage of the test data scatter plot respectively and form multiple partitions, and the lateral stiffness of each partition is determined according to the lateral force and the lateral displacement of each partition; a lateral stiffness curve is generated by fitting the lateral stiffness of each partition; wherein, the load of the preset load interval is less than the preset maximum target load, thereby further improving the accuracy of the static tire lateral stiffness result and making it more convenient for tire characteristic analysis.

[0082] An embodiment of the present application also proposes a static tire lateral force partition fitting device, as Figure 3 shown, the device includes:

[0083] A contact platform 10 that accommodates the test tire and contacts the test tire;

[0084] A loading module 20 for loading a vertical force on the test tire and applying a lateral force to the contact platform 10;

[0085] A positioning module 30 for determining the lateral displacement when relative slippage occurs between the contact platform 10 and the test tire;

[0086] A controller 40 for:

[0087] When receiving a test instruction sent by the user, controlling the loading module 20 to load a vertical force on the test tire at a first preset moving speed until each preset target load is reached and finally the preset maximum target load is reached. Among them, after each preset target load or the preset maximum target load is reached and maintained for a second preset duration, controlling the loading module 20 to apply a lateral force to the contact platform 10 at a second preset moving speed, and determining the lateral displacement through the positioning module 30 when relative slippage occurs between the contact platform 10 and the test tire;

[0088] The control loading module 20 unloads the vertical force on the test tire from the preset maximum target load until it is reduced to each of the preset target loads respectively. Wherein, after each reduction to a preset target load and maintaining the second preset duration, the control loading module 20 applies a lateral force to the contact platform 10 at the second preset moving speed, and determines the lateral displacement through the positioning module 30 when relative slip occurs between the contact platform 10 and the test tire;

[0089] Taking the lateral displacement as the abscissa and the lateral force as the ordinate, plot the scatter diagram of the test data of the lateral force and the lateral displacement;

[0090] According to at least two preset load intervals, divide the load loading stage and the load unloading stage of the test data scatter diagram respectively to form multiple partitions, and determine the lateral rigidity of each partition according to the lateral force and lateral displacement of each partition;

[0091] Generate a lateral rigidity curve by fitting the lateral rigidities of each partition;

[0092] Wherein, the load of the preset load interval is less than the preset maximum target load.

[0093] In a specific application scenario of the present application, the controller 40 is specifically used for:

[0094] Perform separate cubic polynomial fittings on the lateral force and lateral displacement of each partition. Wherein, assume the cubic polynomial fitting formula is y = ax 3 + bx 2 + cx + d, and obtain the numerical values of the constants a, b, and c;

[0095] Take the derivative of the cubic polynomial fitting formula to get the derivative formula y' = 3ax 2 + 2bx + c, and substitute the numerical values of the constants a, b, and c into the derivative formula to determine the lateral rigidity of each partition;

[0096] Wherein, y is the lateral force, x is the lateral displacement, and y' is the lateral rigidity.

[0097] In a specific application scenario of the present application, the preset load interval includes 0% - 30%, 30% - 60%, and 60% - 90% of the preset maximum target load.

[0098] In a specific application scenario of the present application, the preset maximum target load includes 80%, or 100%, or 120% of the maximum load of the test tire.

[0099] In a specific application scenario of the present application, the controller 40 is further used for:[[ID=4I]]

[0100] When receiving a preliminary test instruction sent by a user, control the loading module 20 to load a vertical force on the test tire at the first preset moving speed until reaching a preliminary test load, unload after maintaining for a third preset duration, and repeat a preset number of times for the preliminary test.

[0101] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present application and are not intended to limit them; although the present application has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that they can still modify the technical solutions described in the foregoing embodiments or perform equivalent replacements for some of the technical features; and these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present application.

Claims

1. A static tire lateral force partition fitting method, characterized in that The method includes: Assembling the test tire onto the test rim, inflating the test tire to a preset air pressure and parking it for a first preset duration; Fixing the combination of the test tire and the test rim to the test rigid machine and bringing the test tire into contact with the contact platform; Loading a vertical force on the test tire at a first preset moving speed until reaching each preset target load and finally reaching a preset maximum target load. Among them, after reaching each of the preset target loads or the preset maximum target load and maintaining a second preset duration, applying a lateral force to the contact platform at a second preset moving speed and determining the lateral displacement when relative slip occurs between the contact platform and the test tire; Unloading the vertical force on the test tire from the preset maximum target load until it is reduced to each of the preset target loads respectively. Among them, after reducing to each of the preset target loads and maintaining the second preset duration, applying a lateral force to the contact platform at the second preset moving speed and determining the lateral displacement when relative slip occurs between the contact platform and the test tire; Taking the lateral displacement as the abscissa and the lateral force as the ordinate, plotting a scatter diagram of the test data of the lateral force and the lateral displacement; Dividing the load loading stage and the load unloading stage of the test data scatter diagram according to at least two preset load intervals to form multiple partitions, and determining the lateral rigidity of each partition according to the lateral force and the lateral displacement of each partition; Fitting a lateral rigidity curve according to the lateral rigidity of each partition; Among them, the load of the preset load interval is less than the preset maximum target load.

2. The method according to claim 1, wherein Determining the lateral rigidity of each partition according to the lateral force and the lateral displacement of each partition, specifically: Separate cubic polynomial fittings are performed on the lateral forces and lateral displacements of each partition. Among them, let the cubic polynomial fitting formula be y = ax 3 + bx 2 + cx + d, and the numerical values of the constants a, b, and c are obtained; Derive the cubic polynomial fitting formula to obtain the derivative formula y' = 3ax 2 + 2bx + c. Substitute the values of the constants a, b, and c into the derivative formula to determine the lateral rigidity of each partition; Where y is the lateral force, x is the lateral displacement, and y' is the lateral rigidity.

3. The method according to claim 1, wherein The preset load interval includes 0%-30%, 30%-60%, and 60%-90% of the preset maximum target load.

4. The method according to claim 1, characterized in that, The preset maximum target load includes 80%, or 100%, or 120% of the maximum load of the test tire.

5. The method according to claim 1, wherein Before loading the vertical force on the test tire at a first preset moving speed until reaching each preset target load, the method further includes: Loading the vertical force on the test tire at the first preset moving speed until reaching a pretest load, unloading after maintaining a third preset duration, repeating the preset number of times for pretesting, and inflating the test tire to the preset air pressure after the pretesting is completed.

6. A static tire lateral force partition fitting device, characterized in that, The device includes: A contact platform that accommodates the test tire and contacts the test tire; A loading module for loading a vertical force on the test tire and applying a lateral force to the contact platform; A positioning module for determining the lateral displacement when relative slip occurs between the contact platform and the test tire; A controller for: When receiving a test instruction sent by a user, control the loading module to apply a vertical force to the test tire at a first preset moving speed until each preset target load is reached and finally the preset maximum target load is reached. Among them, after each preset target load or the preset maximum target load is reached and maintained for a second preset duration, control the loading module to apply a lateral force to the contact platform at a second preset moving speed, and determine the lateral displacement through the positioning module when relative slippage occurs between the contact platform and the test tire; Control the loading module to unload the vertical force on the test tire from the preset maximum target load until it is respectively reduced to each preset target load. Among them, after each reduction to a preset target load and maintaining the second preset duration, control the loading module to apply a lateral force to the contact platform at the second preset moving speed, and determine the lateral displacement through the positioning module when relative slippage occurs between the contact platform and the test tire; Taking the lateral displacement as the abscissa and the lateral force as the ordinate, plot a scatter diagram of the test data of the lateral force and the lateral displacement; According to at least two preset load intervals, divide the load loading stage and the load unloading stage of the test data scatter diagram respectively to form multiple partitions, and determine the lateral rigidity of each partition according to the lateral force and the lateral displacement of each partition; Fit a lateral rigidity curve according to the lateral rigidity of each partition; Among them, the load of the preset load interval is less than the preset maximum target load.

7. The device according to claim 6, characterized in that, The controller is specifically used for: Separate cubic polynomial fittings are performed on the lateral forces and lateral displacements of each partition. Among them, the cubic polynomial fitting formula is set as y = ax 3 + bx 2 + cx + d, and the values of the constants a, b, and c are obtained; Derive the cubic polynomial fitting formula to obtain the derivative formula y' = 3ax 2 + 2bx + c. Substitute the numerical values of the constants a, b, and c into the derivative formula to determine the lateral rigidity of each partition; Among them, y is the lateral force, x is the lateral displacement, and y' is the lateral rigidity.

8. The device according to claim 6, characterized in that, The preset load interval includes 0%-30%, 30%-60%, and 60%-90% of the preset maximum target load.

9. The device according to claim 6, characterized in that, The preset maximum target load includes 80%, or 100%, or 120% of the maximum load of the test tire.

10. The device according to claim 6, characterized in that, The controller is further used for: When receiving a pre-test instruction sent by a user, control the loading module to apply a vertical force to the test tire at the first preset moving speed until the pre-test load is reached, unload after maintaining for a third preset duration, and repeat the preset number of times for pre-test.

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