Method and device for determining tire stiffness

Abstract

The present application discloses a method and device for determining tire stiffness. The method includes: determining a first radius of a three-dimensional tire model corresponding to a target tire after inflation and a second radius of the three-dimensional tire model before inflation, and determining the minimum angular velocity and maximum angular velocity of the three-dimensional tire model based on the first radius, the second radius, and the preset linear velocity of the three-dimensional tire model; determining the free rolling angular velocity during the gradual acceleration of the inflated three-dimensional tire model from the minimum angular velocity to the maximum angular velocity; determining multiple lateral forces and multiple self-aligning moments applied to the three-dimensional tire model at multiple preset slip angles during the rolling of the three-dimensional tire model at the free rolling angular velocity, and determining the stiffness of the target tire based on the multiple lateral forces and multiple self-aligning moments. The present application at least solves the technical problem of low tire testing efficiency.

Description

Technical Field

[0001] The present application relates to the field of tire simulation technology, and in particular, to a method and device for determining tire stiffness. Background Art

[0002] Vehicle handling stability and ride smoothness are closely related to the tire's cornering stiffness and return stiffness. Currently, the most direct and effective way to obtain a tire dynamics model is to conduct sample tire testing. During tire product development, the prediction of tire cornering stiffness and return stiffness can be measured using six-component force equipment. However, the testing cost is high and the testing cycle is long, which leads to increased tire trial production costs during product development and a longer development cycle. Summary of the Invention

[0003] The embodiments of the present application provide a method and apparatus for determining tire stiffness, so as to at least solve the technical problem of low tire testing efficiency.

[0004] According to one aspect of an embodiment of the present application, a method for determining tire stiffness is provided, comprising: determining a first radius of a three-dimensional tire model corresponding to a target tire after inflation and a second radius of the three-dimensional tire model before inflation, and determining the minimum angular velocity and maximum angular velocity of the three-dimensional tire model based on the first radius, the second radius, and a preset linear velocity of the three-dimensional tire model; determining a free rolling angular velocity in a process in which the inflated three-dimensional tire model gradually accelerates from the minimum angular velocity to the maximum angular velocity; determining a plurality of lateral forces and a plurality of restoring moments applied to the three-dimensional tire model at a plurality of preset sideslip angles in a process in which the three-dimensional tire model rolls at the free rolling angular velocity, and determining the stiffness of the target tire based on the plurality of lateral forces and the plurality of restoring moments.

[0005] Optionally, the stiffness of the target tire is determined based on multiple lateral forces and multiple righting moments, including: determining a first curve showing how the lateral force acting on the three-dimensional tire model varies with the preset slip angle based on the lateral force acting on the three-dimensional tire model at each preset slip angle among multiple preset slip angles; determining a second curve showing how the righting moment of the three-dimensional tire model varies with the preset slip angle based on the righting moment of the three-dimensional tire model at each preset slip angle; and determining the cornering stiffness of the target tire and the righting stiffness of the target tire based on the first curve and the second curve, respectively, wherein the stiffness of the target tire includes cornering stiffness and righting stiffness.

[0006] Optionally, the cornering stiffness of the target tire and the return stiffness of the target tire are determined based on the first curve and the second curve, respectively, including: linearly fitting the first curve and the second curve, respectively, to obtain a first straight line and a second straight line; determining the slope of the first straight line as the cornering stiffness of the target tire, and determining the slope of the second straight line as the return stiffness of the target tire.

[0007] Optionally, the lateral force acting on the three-dimensional tire model at each preset slip angle is determined by the following method, including: tilting the three-dimensional tire model according to each preset slip angle and maintaining each preset slip angle for a preset time; determining the moment corresponding to the last frame within the preset time as the target moment, and determining the lateral force acting on the three-dimensional tire model at the target moment as the lateral force acting on the three-dimensional tire model at each preset slip angle, wherein each preset slip angle is sequentially spaced by a target angle value.

[0008] Optionally, the three-dimensional tire model corresponding to the target tire is determined in the following manner, including: determining the two-dimensional grid model of each rubber component and skeleton material in the target tire based on the distribution information and material distribution information of each component in the target tire, and embedding the two-dimensional grid model of the skeleton material into the two-dimensional grid model of each rubber component to obtain the two-dimensional tire model corresponding to the target tire; determining the rim model corresponding to the target tire based on the specification parameters of the target tire; assembling the two-dimensional tire model with the rim model, and inflating the assembled two-dimensional tire model to obtain an inflated two-dimensional tire model; and rotating the inflated two-dimensional tire model into a three-dimensional tire model.

[0009] Optionally, a two-dimensional grid model of each rubber component and skeleton material in the target tire is determined based on the distribution and material distribution of each component in the target tire, including: determining each rubber component and skeleton material in the target tire based on the distribution and material distribution of each component in the target tire; determining the grids of each rubber component and skeleton material in the target tire, wherein each grid contains at least the following material properties: rubber density of the rubber component, hyperelastic material parameters, cross-sectional area of ​​the skeleton material, density of the skeleton material, and elastic modulus of the skeleton material; constructing a two-dimensional tire model based on the grid type corresponding to each grid, the unit type corresponding to the grid, and the material properties contained in the grid, wherein the grid types of the rubber component include: triangular grid and quadrilateral grid, the unit type corresponding to the grid of the rubber component is H unit, the grid type corresponding to the grid of the skeleton material is line unit, and the unit type corresponding to the grid of the skeleton material is surface unit.

[0010] Optionally, after determining the three-dimensional tire model, the method further includes: constructing a road surface model, and determining a road surface reference point in the road surface model and a friction coefficient between the road surface model and the three-dimensional tire model; controlling the contact between the road surface reference point in the road surface model and the tire surface of the three-dimensional tire model; and applying a load to the road surface reference point to complete the loading of the three-dimensional tire model.

[0011] According to another aspect of an embodiment of the present application, a device for determining tire stiffness is also provided, including: a first determination module, used to determine a first radius of a three-dimensional tire model corresponding to a target tire after inflation and a second radius of the three-dimensional tire model before inflation, and determine the minimum angular velocity and maximum angular velocity of the three-dimensional tire model based on the first radius, the second radius and the preset linear velocity of the three-dimensional tire model; a second determination module, used to determine the free rolling angular velocity in the process of the three-dimensional tire model gradually accelerating from the minimum angular velocity to the maximum angular velocity after inflation; a third determination module, used to determine multiple lateral forces and multiple restoring moments received by the three-dimensional tire model at multiple preset sideslip angles in the process of the three-dimensional tire model rolling at the free rolling angular velocity, and determine the stiffness of the target tire based on the multiple lateral forces and multiple restoring moments.

[0012] According to another aspect of the embodiments of the present application, a non-volatile storage medium is provided, in which a program is stored. When the program is executed, the device where the non-volatile storage medium is located is controlled to execute the above-mentioned tire stiffness determination method.

[0013] According to another aspect of the embodiments of the present application, a computer device is provided, including: a memory and a processor, wherein the processor is configured to run a program stored in the memory, wherein the above-mentioned tire stiffness determination method is executed when the program is run.

[0014] In an embodiment of the present application, a first radius of a three-dimensional tire model corresponding to a target tire after inflation and a second radius of the three-dimensional tire model before inflation are determined, and the minimum angular velocity and maximum angular velocity of the three-dimensional tire model are determined based on the first radius, the second radius, and a preset linear velocity of the three-dimensional tire model; a free rolling angular velocity is determined during the gradual acceleration of the inflated three-dimensional tire model from the minimum angular velocity to the maximum angular velocity; and a plurality of lateral forces and a plurality of aligning moments exerted on the three-dimensional tire model at a plurality of preset slip angles during the rolling of the three-dimensional tire model at the free rolling angular velocity are determined, and the stiffness of the target tire is determined based on the plurality of lateral forces and a plurality of aligning moments. By using a simulated three-dimensional tire model of the target tire to determine the plurality of lateral forces and a plurality of aligning moments exerted on the three-dimensional tire model at a plurality of preset slip angles during the rolling of the three-dimensional tire model at the free rolling angular velocity, and then determining the stiffness of the target tire, the technical effect of using a three-dimensional tire model to determine the tire stiffness is achieved instead of using a physical sample tire, thereby solving the technical problem of low tire testing efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] The drawings described herein are used to provide a further understanding of the present application and constitute a part of the present application. The illustrative embodiments of the present application and their descriptions are used to explain the present application and do not constitute an improper limitation on the present application. In the drawings:

[0016] Figure 1 This is a hardware structure block diagram of a computer terminal (or mobile device) for a method for determining tire stiffness according to an embodiment of the present application;

[0017] Figure 2 is a flow chart of a method for determining tire stiffness according to the present application;

[0018] Figure 3 is a first straight line schematic diagram reflecting the relationship between the tire lateral force and the preset sideslip angle according to an embodiment of the present application;

[0019] Figure 4 is a second straight line schematic diagram reflecting the relationship between the tire aligning torque and the preset sideslip angle according to an embodiment of the present application;

[0020] Figure 5 Schematic diagram of a tire footprint of a three-dimensional tire model according to an embodiment of the present application when the side slip angle is 1 degree;

[0021] Figure 6 is a two-dimensional grid schematic diagram of a rubber component according to an embodiment of the present application;

[0022] Figure 7 is a schematic diagram of a skeleton material grid according to an embodiment of the present application;

[0023] Figure 8 This is a schematic diagram of a three-dimensional tire model according to an embodiment of the present application;

[0024] Figure 9 This is a comparison diagram of the lateral stiffness under different loads under simulation and test in the embodiment of the present application;

[0025] Figure 10 This is a comparison diagram of the return stiffness simulation and test under different loads in the embodiment of the present application;

[0026] Figure 11 This is a comparison diagram of the lateral stiffness simulation and test under different schemes in the embodiment of the present application;

[0027] Figure 12 This is a comparison diagram of the return stiffness simulation and test under different schemes in the embodiment of the present application;

[0028] Figure 13 It is a structural schematic diagram of an optional device for determining tire stiffness in an embodiment of the present application. DETAILED DESCRIPTION

[0029] In order to enable those skilled in the art to better understand the present invention, the following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments in the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts should fall within the scope of protection of this application.

[0030] It should be noted that the terms "first", "second", etc. in the specification and claims of the present application and the above-mentioned drawings are used to distinguish similar objects and are not necessarily used to describe a specific order or sequential order. It should be understood that the data used in this way can be interchangeable where appropriate, so that the embodiments of the present application described herein can be implemented in a sequence other than those illustrated or described herein. In addition, the terms "including" and "having" and any of their variations are intended to cover non-exclusive inclusions, for example, a process, method, system, product or device comprising a series of steps or units is not necessarily limited to those steps or units clearly listed, but may include other steps or units that are not clearly listed or inherent to these processes, methods, products or devices.

[0031] In the related art, tire stiffness is measured by performing sample testing. During tire product development, predictions of tire cornering stiffness and return stiffness can be measured using six-component force equipment, but this is expensive and time-consuming. To address this issue, an embodiment of the present application provides an embodiment of a method for determining tire stiffness. It should be noted that the steps shown in the flowcharts of the accompanying drawings can be executed in a computer system, such as a set of computer-executable instructions, and that although a logical order is shown in the flowcharts, in some cases, the steps shown or described can be executed in a different order than that shown.

[0032] The method embodiments provided in the embodiments of the present application can be executed in a mobile terminal, a computer terminal or a similar computing device. Figure 1 FIG1 shows a hardware structure block diagram of a computer terminal (or mobile device) for implementing a method for determining tire stiffness. Figure 1As shown, the computer terminal 10 (or mobile device 10) may include one or more (illustrated as 102a, 102b, ..., 102n) processors 102 (the processor 102 may include but is not limited to a processing device such as a microprocessor MCU or a programmable logic device FPGA), a memory 104 for storing data, and a transmission module 106 for communication functions. In addition, it may also include: a display, an input / output interface (I / O interface), a universal serial bus (USB) port (which may be included as one of the ports of the BUS bus), a network interface, a power supply and / or a camera. It will be understood by those skilled in the art that Figure 1 The structure shown is only for illustration and does not limit the structure of the above electronic device. Figure 1 More or fewer components than shown, or with Figure 1 Different configurations shown.

[0033] It should be noted that the one or more processors 102 and / or other data processing circuits described above may generally be referred to herein as "data processing circuitry". The data processing circuitry may be embodied in whole or in part as software, hardware, firmware, or any other combination thereof. In addition, the data processing circuitry may be a single independent processing module, or may be incorporated in whole or in part into any of the other components of the computer terminal 10 (or mobile device). As described in the embodiments of the present application, the data processing circuitry serves as a processor control (e.g., selection of a variable resistor terminal path connected to an interface).

[0034] Memory 104 can be used to store software programs and modules for application software, such as the program instructions / data storage device corresponding to the tire stiffness determination method described in the embodiments of the present application. Processor 102 executes the software programs and modules stored in memory 104 to perform various functional applications and data processing, thereby implementing the tire stiffness determination method described above. Memory 104 can include high-speed random access memory (RAM) and non-volatile memory, such as one or more magnetic storage devices, flash memory, or other non-volatile solid-state memory. In some examples, memory 104 may further include memory located remotely from processor 102, which can be connected to computer terminal 10 via a network. Examples of such networks include, but are not limited to, the Internet, corporate intranets, local area networks, mobile communication networks, and combinations thereof.

[0035] The transmission device 106 is configured to receive or transmit data via a network. A specific example of the aforementioned network may include a wireless network provided by the communications provider of the computer terminal 10. In one embodiment, the transmission device 106 includes a network interface controller (NIC), which can be connected to other network devices via a base station to enable communication with the Internet. In another embodiment, the transmission device 106 may be a radio frequency (RF) module, which is configured to communicate with the Internet wirelessly.

[0036] The display may be, for example, a touch screen liquid crystal display (LCD) that enables a user to interact with a user interface of the computer terminal 10 (or mobile device).

[0037] Under the above operating environment, the embodiment of the present application provides a method for determining tire stiffness, such as Figure 2 As shown, the method includes the following steps:

[0038] Step S202, determining a first radius of the three-dimensional tire model corresponding to the target tire after inflation and a second radius of the three-dimensional tire model before inflation, and determining a minimum angular velocity and a maximum angular velocity of the three-dimensional tire model based on the first radius, the second radius, and a preset linear velocity of the three-dimensional tire model;

[0039] Step S204, determining the free rolling angular velocity during the process of the inflated three-dimensional tire model gradually accelerating from the minimum angular velocity to the maximum angular velocity;

[0040] Step S206 , while the three-dimensional tire model rolls at the free rolling angular velocity, multiple lateral forces and multiple aligning moments applied to the three-dimensional tire model at multiple preset slip angles are determined, and the stiffness of the target tire is determined based on the multiple lateral forces and multiple aligning moments.

[0041] Through the above steps, by using a simulated three-dimensional tire model of the target tire to roll at a free rolling angular velocity, multiple lateral forces and multiple restoring moments acting on the three-dimensional tire model at multiple preset slip angles are determined, and then the rigidity of the target tire is determined. This achieves the technical effect of using a three-dimensional tire model instead of a physical sample tire to determine tire rigidity, thereby solving the technical problem of low tire testing efficiency.

[0042] In step S202 , finite element modeling of the target tire may be performed using finite element software, such as ABAQUS (an engineering simulation finite element software).

[0043] In step S204, the free angular velocity can be determined by setting two analysis steps. For example, in the first analysis step, the tire rolls at the minimum angular velocity, and in the second analysis step, the tire rolls at the maximum angular velocity. From the first analysis step to the second analysis step, the free rolling angular velocity is found based on the tire lateral torque. In an optional method, when the tire lateral torque is 0, the angular velocity at this moment is determined to be the free rolling angular velocity.

[0044] Steps S202 to S206 are described below through a specific embodiment.

[0045] In step S206, the method for determining the stiffness of the target tire based on multiple lateral forces and multiple righting moments includes: determining a first curve showing how the lateral force acting on the three-dimensional tire model varies with the preset slip angle based on the lateral force acting on the three-dimensional tire model at each preset slip angle among multiple preset slip angles; determining a second curve showing how the righting moment of the three-dimensional tire model varies with the preset slip angle based on the righting moment of the three-dimensional tire model at each preset slip angle; and determining the cornering stiffness of the target tire and the righting stiffness of the target tire based on the first curve and the second curve, respectively, wherein the stiffness of the target tire includes: cornering stiffness and righting stiffness.

[0046] It should be noted that the multiple preset slip angles can be multiple preset slip angles with continuously spaced target angle values. For example, if the target angle value is 0.2 degrees and the first preset slip angle is -1 degree, the subsequent preset slip angles can be -0.8 degrees, -0.6 degrees, -0.4 degrees, -0.2 degrees, etc.

[0047] In some embodiments of the present application, after obtaining the first curve and the second curve, the first curve and the second curve can be linearly fitted to obtain a first straight line and a second straight line; the slope of the first straight line is determined as the cornering stiffness of the target tire, and the slope of the second straight line is determined as the return stiffness of the target tire. Figure 3 shows a schematic diagram of a first straight line, Figure 3 In the figure, the change of the lateral force on the target tire is shown when the slip angle changes from -1 degree to 1 degree. Figure 4 shows a schematic diagram of a second straight line, Figure 4 , the change of the aligning torque of the target tire when the slip angle changes from -1 degree to 1 degree is shown in sequence.

[0048] In an optional manner, the lateral force acting on the three-dimensional tire model at each preset slip angle can be determined by the following steps: the three-dimensional tire model is tilted according to each preset slip angle and each preset slip angle is maintained for a preset duration; the moment corresponding to the last frame within the preset duration is determined as the target moment, and the lateral force acting on the three-dimensional tire model at the target moment is determined as the lateral force acting on the three-dimensional tire model at each preset slip angle, wherein each preset slip angle is sequentially spaced by a target angle value.

[0049] In actual application scenarios, multiple preset slip angles of the tire can be set to -1 degree, -0.8 degree, -0.6 degree, -0.4 degree, -0.2 degree, 0 degree, 0.2 degree, 0.4 degree, 0.6 degree, 0.8 degree and 1 degree. During the tire slip process, the preset time is maintained every 0.2 degrees. During the simulation analysis using ABAQUS software, an analysis step can be set at each preset slip angle, and the lateral force and return torque of the last frame in each analysis step can be extracted.

[0050] Figure 5 The footprint of the target tire is shown at a preset slip angle of 1 degree.

[0051] Optionally, the three-dimensional tire model corresponding to the target tire is determined in the following manner, including: determining the two-dimensional grid model of each rubber component and skeleton material in the target tire based on the distribution information and material distribution information of each component in the target tire, and embedding the two-dimensional grid model of the skeleton material into the two-dimensional grid model of each rubber component to obtain the two-dimensional tire model corresponding to the target tire; determining the rim model corresponding to the target tire based on the specification parameters of the target tire; assembling the two-dimensional tire model with the rim model, and inflating the assembled two-dimensional tire model to obtain an inflated two-dimensional tire model; and rotating the inflated two-dimensional tire model into a three-dimensional tire model.

[0052] Specifically, the interaction properties of the contact between the tire and the rim are set, the friction coefficient of the contact between the tire and the rim is set, and according to the preset boundary conditions, the two-dimensional tire model is pushed with a certain pressure to assemble the two-dimensional tire model with the rim. Finally, the inflation pressure is set for the surface set of the inner contour of the two-dimensional tire model to complete the inflation of the two-dimensional tire model.

[0053] The steps to convert an inflated 2D tire model into a 3D tire model are as follows:

[0054] Read the 2D inflation result and use the symmetric model command to rotate the 2D tire model into a 3D tire model. The number of rotations can be set to 120, and the 3D tire model is inflated according to the preset inflation pressure.

[0055] In some embodiments of the present application, the two-dimensional grid model of each rubber component and skeleton material in the target tire can be determined in the following manner: determine each rubber component and skeleton material in the target tire according to the distribution and material distribution of each component in the target tire; determine the grid of each rubber component and skeleton material in the target tire, wherein each grid contains at least the following material properties: rubber density of the rubber component, hyperelastic material parameters, cross-sectional area of ​​the skeleton material, density of the skeleton material and elastic modulus of the skeleton material; construct a two-dimensional tire model according to the grid type corresponding to each grid, the cell type corresponding to the grid and the material properties contained in the grid, wherein the grid types of the rubber component include: triangular grid and quadrilateral grid, the cell type corresponding to the grid of the rubber component is H cell, the grid type corresponding to the grid of the skeleton material is line cell, and the cell type corresponding to the grid of the skeleton material is surface cell.

[0056] Specifically, the material distribution map of the target tire is processed using CAD software, and the junctions of the components are partitioned. The rubber components and the skeleton materials must be distinguished. After the material distribution map is processed, three files are generated, namely the outer contour, the skeleton material, and the segmented part. The CAD-processed files are imported into the Abaqus software for two-dimensional mesh division. First, the three CAD files are imported into the sketch to establish the mesh of each rubber component (such as Figure 6 As shown) and the skeleton material mesh (as Figure 7 As shown in FIG, each adhesive component and skeleton material set, contact surface set and point set are established, and the skeleton material grid is embedded in the adhesive component unit grid.

[0057] Assign properties to each material in the two-dimensional grid, including the density and hyperelastic material parameters of each rubber component, and the cross-sectional area, density, and elastic modulus properties of the skeleton material;

[0058] Set the mesh type. The mesh of the rubber part is quadrilateral and triangle, the unit type is H unit (a finite element unit), the skeleton material is line unit, and the unit type is surface unit (a finite element unit); establish the rim model according to the tire specifications, set the rim as an analytical rigid body, and establish a face set.

[0059] Optionally, after determining the three-dimensional tire model, the method further includes: constructing a road surface model, and determining a road surface reference point in the road surface model and a friction coefficient between the road surface model and the three-dimensional tire model; controlling the contact between the road surface reference point in the road surface model and the tire surface of the three-dimensional tire model; and applying a load to the road surface reference point to complete the loading of the three-dimensional tire model.

[0060] Specifically, a road surface model is established, and the road surface model is set as an analytical rigid body. A surface set and road surface reference points are established, and the friction coefficient between the road surface and the tire is set. The following are the analysis steps for setting up the calculation: Step 1: Inflate the tire according to the specified inflation pressure; Step 2: Give the road surface reference point a certain displacement to make it contact with the tire surface; Step 3: Apply the required load to the road surface reference point. The tire loading step is completed. Figure 8 A loaded three-dimensional tire model is shown.

[0061] In order to verify the accuracy of the simulation method, we compared the simulation data under different working conditions with the test data. Figure 9 As shown, the maximum comparison error is within 4%, and the comparison of the return stiffness under different loads is as follows. Figure 10 As shown, the maximum comparison error is within 9%. At the same time, the trend comparison between different schemes is carried out, and the lateral stiffness comparison is as follows. Figure 11 As shown, Scheme 4>Scheme 2>Scheme 1>Scheme 3; the comparison of return stiffness is as follows Figure 12 As shown, Scheme 4 > Scheme 2 > Scheme 1 > Scheme 3. The simulation and test trends among the schemes are consistent. In one optional method, different schemes correspond to different tire specifications.

[0062] The embodiment of the present application provides a device for determining tire stiffness, such as Figure 13 As shown, it includes: a first determination module 110, which is used to determine a first radius of the three-dimensional tire model corresponding to the target tire after inflation and a second radius of the three-dimensional tire model before inflation, and determine the minimum angular velocity and maximum angular velocity of the three-dimensional tire model according to the first radius, the second radius and the preset linear velocity of the three-dimensional tire model; a second determination module 112, which is used to determine the free rolling angular velocity in the process of the three-dimensional tire model gradually accelerating from the minimum angular velocity to the maximum angular velocity after inflation; a third determination module 114, which is used to determine multiple lateral forces and multiple self-aligning moments exerted on the three-dimensional tire model at multiple preset sideslip angles during the process of the three-dimensional tire model rolling at the free rolling angular velocity, and determine the stiffness of the target tire according to the multiple lateral forces and multiple self-aligning moments.

[0063] The third determination module 114 includes: a first determination submodule and a second determination submodule. The first determination submodule is used to determine a first curve showing how the lateral force on the three-dimensional tire model changes with the preset slip angle based on the lateral force on the three-dimensional tire model at each preset slip angle among multiple preset slip angles; determine a second curve showing how the righting torque of the three-dimensional tire model changes with the preset slip angle based on the righting torque of the three-dimensional tire model at each preset slip angle; and determine the cornering stiffness and the righting stiffness of the target tire based on the first curve and the second curve, respectively, wherein the stiffness of the target tire includes cornering stiffness and righting stiffness.

[0064] The first determination submodule includes: a first determination unit and a second determination unit, the first determination unit being used to perform linear fitting on the first curve and the second curve respectively to obtain a first straight line and a second straight line; determining the slope of the first straight line as the cornering stiffness of the target tire, and determining the slope of the second straight line as the self-aligning stiffness of the target tire.

[0065] The second determination unit is used to determine the lateral force exerted on the three-dimensional tire model at each preset slip angle in the following manner, including: deflecting the three-dimensional tire model according to each preset slip angle and maintaining each preset slip angle for a preset duration; determining the moment corresponding to the last frame within the preset duration as the target moment, and determining the lateral force exerted on the three-dimensional tire model at the target moment as the lateral force exerted on the three-dimensional tire model at each preset slip angle, wherein each preset slip angle is sequentially spaced by a target angle value.

[0066] The second determination submodule is used to determine the two-dimensional grid models of each rubber component and the skeleton material in the target tire based on the distribution information and material distribution information of each component in the target tire, and embed the two-dimensional grid model of the skeleton material into the two-dimensional grid model of each rubber component to obtain a two-dimensional tire model corresponding to the target tire; determine the rim model corresponding to the target tire based on the specification parameters of the target tire; assemble the two-dimensional tire model with the rim model, and inflate the assembled two-dimensional tire model to obtain an inflated two-dimensional tire model; and rotate the inflated two-dimensional tire model into a three-dimensional tire model.

[0067] The second determination submodule includes: a third determination unit and a loading unit, wherein the third determination unit is used to determine the rubber components and skeleton materials in the target tire according to the distribution and material distribution of the components in the target tire; determine the grids of the rubber components and skeleton materials in the target tire, wherein each grid contains at least the following material properties: the rubber density of the rubber component, the hyperelastic material parameter, the cross-sectional area of ​​the skeleton material, the density of the skeleton material, and the elastic modulus of the skeleton material; construct a two-dimensional tire model according to the grid type corresponding to each grid, the cell type corresponding to the grid, and the material properties contained in the grid, wherein the grid types of the rubber components include: triangular grids and quadrilateral grids, the cell type corresponding to the grid of the rubber components is H cell, the grid type corresponding to the grid of the skeleton material is line cell, and the cell type corresponding to the grid of the skeleton material is surface cell.

[0068] The loading unit is used to construct a road surface model and determine the road surface reference points in the road surface model and the friction coefficient between the road surface model and the three-dimensional tire model; control the contact between the road surface reference points in the road surface model and the tire surface of the three-dimensional tire model; and apply loads to the road surface reference points to complete the loading of the three-dimensional tire model.

[0069] According to another aspect of the embodiments of the present application, a non-volatile storage medium is provided, in which a program is stored. When the program is executed, the device where the non-volatile storage medium is located is controlled to execute the above-mentioned tire stiffness determination method.

[0070] According to another aspect of the embodiments of the present application, a computer device is provided, including: a memory and a processor, wherein the processor is configured to run a program stored in the memory, wherein the above-mentioned method for determining tire stiffness is executed when the program is run.

[0071] It should be noted that the various modules in the above-mentioned tire stiffness determination device can be program modules (for example, a set of program instructions that implement a certain specific function) or hardware modules. For the latter, it can be expressed in the following forms, but is not limited to this: the expression form of each of the above-mentioned modules is a processor, or the functions of each of the above-mentioned modules are implemented by a processor.

[0072] The serial numbers of the above embodiments of the present application are for description only and do not represent the advantages or disadvantages of the embodiments.

[0073] In the above embodiments of the present application, the description of each embodiment has its own focus. For parts that are not described in detail in a certain embodiment, please refer to the relevant description of other embodiments.

[0074] In the several embodiments provided in this application, it should be understood that the disclosed technical content can be implemented in other ways. Among them, the device embodiments described above are only exemplary. For example, the division of units can be a logical function division. In actual implementation, there may be other division methods, such as multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the mutual coupling or direct coupling or communication connection shown or discussed can be through some interfaces, indirect coupling or communication connection of units or modules, which can be electrical or other forms.

[0075] Units described as separate components may or may not be physically separate, and components shown as units may or may not be physical units, that is, they may be located in one place or distributed across multiple units. Some or all of the units may be selected to achieve the purpose of the present embodiment according to actual needs.

[0076] In addition, the functional units in the various embodiments of the present application may be integrated into a single processing unit, or each unit may exist physically separately, or two or more units may be integrated into a single unit. The aforementioned integrated units may be implemented in the form of hardware or software functional units.

[0077] If the integrated unit is implemented in the form of a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present application, or the part that contributes to the relevant technology, or all or part of the technical solution can be embodied in the form of a software product, which is stored in a storage medium and includes several instructions for enabling a computer device (which can be a personal computer, server or network device, etc.) to execute all or part of the steps of the various embodiments of the present application. The aforementioned storage medium includes: various media that can store program codes, such as a USB flash drive, a read-only memory (ROM), a random access memory (RAM), a mobile hard disk, a magnetic disk or an optical disk.

[0078] The above is only a preferred embodiment of the present application. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principles of the present application. These improvements and modifications should also be regarded as the scope of protection of the present application.

Claims

1. A method for determining tire stiffness, characterized in that: include: determining a first radius of a three-dimensional tire model corresponding to a target tire after inflation and a second radius of the three-dimensional tire model before inflation, and determining a minimum angular velocity and a maximum angular velocity of the three-dimensional tire model based on the first radius, the second radius, and a preset linear velocity of the three-dimensional tire model; determining a free rolling angular velocity according to a lateral moment of the three-dimensional tire model during the process of gradually accelerating the inflated three-dimensional tire model from the minimum angular velocity to the maximum angular velocity; determining, during the rolling of the three-dimensional tire model at the free rolling angular velocity, a plurality of lateral forces and a plurality of aligning moments exerted on the three-dimensional tire model at a plurality of preset slip angles, and determining the stiffness of the target tire based on the plurality of lateral forces and the plurality of aligning moments; Among them, determining the multiple lateral forces exerted on the three-dimensional tire model at multiple preset slip angles includes: tilting the three-dimensional tire model according to each preset slip angle and maintaining each preset slip angle for a preset duration; determining the moment corresponding to the last frame within the preset duration as the target moment, and determining the lateral force exerted on the three-dimensional tire model at the target moment as the lateral force exerted on the three-dimensional tire model at each preset slip angle, wherein each preset slip angle is sequentially spaced by a target angle value.

2. The method according to claim 1, characterized in that Determining the stiffness of the target tire according to the multiple lateral forces and the multiple aligning moments includes: determining, based on the lateral force applied to the three-dimensional tire model at each of the plurality of preset slip angles, a first curve showing a change in the lateral force applied to the three-dimensional tire model as a function of the preset slip angle; Determining a second curve of the return moment of the three-dimensional tire model varying with the preset slip angle according to the return moment of the three-dimensional tire model at each preset slip angle; The cornering stiffness of the target tire and the return stiffness of the target tire are determined according to the first curve and the second curve respectively, wherein the stiffness of the target tire includes: the cornering stiffness and the return stiffness.

3. The method according to claim 2, characterized in that Determining the cornering stiffness of the target tire and the righting stiffness of the target tire according to the first curve and the second curve, respectively, includes: Performing linear fitting on the first curve and the second curve respectively to obtain a first straight line and a second straight line; The slope of the first straight line is determined as the cornering stiffness of the target tire, and the slope of the second straight line is determined as the righting stiffness of the target tire.

4. The method according to claim 1, wherein The three-dimensional tire model corresponding to the target tire is determined by: Determining a two-dimensional grid model of each rubber component and a skeleton material in the target tire based on the distribution information and material distribution information of each component in the target tire, and embedding the two-dimensional grid model of the skeleton material into the two-dimensional grid model of each rubber component to obtain a two-dimensional tire model corresponding to the target tire; Determining a rim model corresponding to the target tire according to specification parameters of the target tire; Assembling the two-dimensional tire model and the rim model, and inflating the assembled two-dimensional tire model to obtain an inflated two-dimensional tire model; The inflated two-dimensional tire model is rotated into the three-dimensional tire model.

5. The method according to claim 4, characterized in that Determining a two-dimensional grid model of each rubber component and skeleton material in the target tire according to the distribution and material distribution of each component in the target tire includes: Determining the rubber components and the frame materials of the target tire according to the distribution and material distribution of the components in the target tire; Determining grids for each rubber component and frame material in the target tire, wherein each grid contains at least the following material properties: rubber density of the rubber component, hyperelastic material parameters, cross-sectional area of ​​the frame material, density of the frame material, and elastic modulus of the frame material; The two-dimensional tire model is constructed according to the mesh type corresponding to each mesh, the unit type corresponding to the mesh, and the material properties contained in the mesh, wherein the mesh types of the rubber component include: triangular mesh and quadrilateral mesh, the unit type corresponding to the mesh of the rubber component is H unit, the mesh type corresponding to the mesh of the skeleton material is line unit, and the unit type corresponding to the mesh of the skeleton material is surface unit.

6. The method according to claim 1, characterized in that After determining the three-dimensional tire model, the method further includes: Constructing a road surface model, and determining a road surface reference point in the road surface model and a friction coefficient between the road surface model and the three-dimensional tire model; controlling a road surface reference point in the road surface model to contact a tire surface of the three-dimensional tire model; A load is applied to the road surface reference point to complete the loading of the three-dimensional tire model.

7. A device for determining tire stiffness, characterized in that: include: a first determining module, configured to determine a first radius of a three-dimensional tire model corresponding to a target tire after inflation and a second radius of the three-dimensional tire model before inflation, and to determine a minimum angular velocity and a maximum angular velocity of the three-dimensional tire model based on the first radius, the second radius, and a preset linear velocity of the three-dimensional tire model; a second determining module, configured to determine a free rolling angular velocity according to a lateral torque of the three-dimensional tire model during a process in which the inflated three-dimensional tire model gradually accelerates from the minimum angular velocity to the maximum angular velocity; The third determination module is used to determine the multiple lateral forces and multiple restoring moments that the three-dimensional tire model is subjected to at multiple preset slip angles during the process of the three-dimensional tire model rolling at the free rolling angular velocity, and determine the stiffness of the target tire based on the multiple lateral forces and the multiple restoring moments; wherein, determining the multiple lateral forces that the three-dimensional tire model is subjected to at multiple preset slip angles includes: tilting the three-dimensional tire model at each preset slip angle and maintaining each preset slip angle for a preset time; determining the moment corresponding to the last frame within the preset time as the target moment, and determining the lateral force that the three-dimensional tire model is subjected to at the target moment as the lateral force that the three-dimensional tire model is subjected to at each preset slip angle, wherein each preset slip angle is sequentially spaced by target angle values.

8. A non-volatile storage medium, characterized in that: The non-volatile storage medium stores a program, wherein when the program is executed, the device where the non-volatile storage medium is located is controlled to execute the tire stiffness determination method according to any one of claims 1 to 6.

9. A computer device, characterized in that: include: A memory and a processor, wherein the processor is configured to run a program stored in the memory, wherein the method for determining tire stiffness according to any one of claims 1 to 6 is executed when the program is run.

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