Tire control performance index coefficient automatic generation method and system

Abstract

The invention discloses a tire control performance index coefficient automatic generation method and system, and the method comprises the steps: employing vehicle dynamics simulation software to generate a tire dynamics model, and obtaining a model file; obtaining a load parameter input by a user; the load parameters comprise a front axle load and a rear axle load; reading the model file, and obtaining a first calculation coefficient of the tire from the model file; substituting the first calculation coefficient into a magic formula to obtain a first fitting function; calling a first fitting function, calculating according to the load parameters to obtain force and torque of each working condition, and obtaining a first calculation result; according to the first calculation result and the load parameter, calculating a tire control index coefficient under each working condition through an index calculation formula; and outputting the tire control index coefficient to a preset result file, and generating a tire control performance index coefficient result report. According to the method, the tire control performance index coefficient can be accurately and efficiently generated, so that the tire modeling standardization is improved, and the method can be widely applied to the technical field of computers.

Description

Technical Field

[0001] The present application relates to the field of computer technology, and in particular to a method and system for automatically generating tire handling performance index coefficients. Background Art

[0002] In the related art, manual modeling is usually used for tire handling performance index coefficients. When the analysis task is large, it will consume a lot of manpower and time, the modeling efficiency is low, and sometimes manual operation errors may occur, resulting in calculation errors, which is not conducive to modeling accuracy. Summary of the invention

[0003] The main purpose of the embodiments of the present application is to propose a method and system for automatically generating tire handling performance index coefficients, aiming to achieve accurate and efficient generation of tire handling performance index coefficients to improve tire modeling standardization.

[0004] To achieve the above-mentioned purpose, one aspect of an embodiment of the present application proposes a method and system method for automatically generating a tire handling performance index coefficient, the method comprising:

[0005] Generate a tire dynamics model using vehicle dynamics simulation software to obtain a model file;

[0006] Obtaining load parameters input by a user; wherein the load parameters include front axle load and rear axle load;

[0007] Reading the model file, and acquiring a first calculation coefficient of the tire from the model file;

[0008] Substituting the first calculation coefficient into the magic formula to obtain a first fitting function;

[0009] Calling the first fitting function, calculating the force and moment of each working condition according to the load parameters, and obtaining a first calculation result;

[0010] Calculating the tire handling index coefficient under each of the working conditions by using an index calculation formula according to the first calculation result and the load parameter;

[0011] The tire handling index coefficient is output to a preset result file to generate a tire handling performance index coefficient result report.

[0012] In some embodiments, the step of generating a tire dynamics model using vehicle dynamics simulation software to obtain a model file includes the following steps:

[0013] Obtain tire test data and tire specifications;

[0014] Based on the tdft tool of ADAMS software, a tire PAC2002 dynamic model is generated according to the test data and the tire specifications to obtain a model file.

[0015] In some embodiments, the step of reading the model file and obtaining the first calculation coefficient of the tire from the model file comprises the following steps:

[0016] Configuring a key tag string, and determining a key position of the model file according to the key tag string; wherein the key tag string includes a first tag string, a second tag string, a third tag string and a fourth tag string;

[0017] Continue reading the model file from the key position corresponding to the first mark character string to obtain a first result character string, and perform character string segmentation and numerical conversion on the first result character string to obtain a tire radius parameter;

[0018] Continue reading the model file from the key position corresponding to the second mark character string to obtain a second result character string, and perform character string segmentation and numerical conversion on the second result character string to obtain a tire standard load parameter;

[0019] Continue reading the model file from the key position corresponding to the third mark character string to obtain a third result character string, and perform character string segmentation and numerical conversion on the third result character string to obtain a plurality of lateral force calculation coefficients;

[0020] Continue reading the model file from the key position corresponding to the fourth mark character string to obtain a fourth result character string, and perform character string segmentation and value conversion on the fourth result character string to obtain a plurality of self-aligning torque calculation coefficients;

[0021] The tire radius parameter, the tire standard load parameter, the lateral force calculation coefficient and the self-aligning moment calculation coefficient are used as the first calculation coefficient of the tire.

[0022] In some embodiments, substituting the first calculation coefficient into the magic formula to obtain a first fitting function comprises the following steps:

[0023] Obtaining a lateral force calculation coefficient and a self-aligning moment calculation coefficient from the first calculation coefficient;

[0024] Construct the magic formula;

[0025] Taking the slip angle, longitudinal slip rate, roll angle and target load as input variables, a lateral force fitting function is constructed in MATLAB software; wherein the lateral force fitting function is obtained by substituting the lateral force calculation coefficient into the magic formula;

[0026] Taking the sideslip angle, the longitudinal slip rate, the roll angle and the target load as input variables, a self-aligning moment fitting function is constructed in MATLAB software; wherein the self-aligning moment fitting function is obtained by substituting the self-aligning moment calculation coefficient into the magic formula;

[0027] The lateral force fitting function and the self-aligning moment fitting function are used as the first fitting function.

[0028] In some embodiments, the first fitting function includes a lateral force fitting function and a aligning moment fitting function, wherein:

[0029] The expression of the lateral force fitting function is:

[0030] F y =F y0 (α,γ,F z );

[0031]

[0032] The expression of the aligning moment fitting function is:

[0033] M′ z =M z0 (α,γ,F z );

[0034] M z0 =-t·F y0 +M zr ;

[0035] t(α t )=D t cos[C t arctan{B t α t -E t (B t α t -arctan(B t α t ))}]cos(α);

[0036] Among them, F y is the lateral force obtained by fitting; M′ z is the fitting return torque; F y0 is the lateral force fitting function; α, α y and α t is the slip angle; γ is the roll angle; F z is the load; D y and D t is the peak factor; C y and C t is the shape factor; By and B t is the stiffness factor; E y and E t Curvature factor; It is the lateral force caused by the longitudinal slip rate.

[0037] In some embodiments, the index coefficient calculation formula includes a sideslip coefficient index coefficient calculation formula, a load transfer sensitivity index coefficient calculation formula, and a load sensitivity index coefficient calculation formula, wherein:

[0038] The calculation formula of the cornering coefficient index coefficient is:

[0039]

[0040] The load transfer sensitivity index coefficient calculation formula is:

[0041]

[0042] The load sensitivity index coefficient calculation formula is:

[0043]

[0044] Among them, F(α) is the sideslip coefficient index coefficient; Fy is the lateral force fitting function; α is the sideslip angle; Fz is the load parameter; G(Fz, α) is the load transfer sensitivity index coefficient; Δ is the left and right load transfer amount of the front axle or rear axle; H(Fz, α) is the load sensitivity index coefficient.

[0045] In some embodiments, the step of outputting the tire handling index coefficient to a preset result file to generate a tire handling performance index coefficient result report comprises the following steps:

[0046] Create an Excel file in the target directory and get the preset result file;

[0047] The excel file reading function of MATLAB is called to output the calculation result to the preset result file, and the file is saved to obtain a tire handling performance index coefficient result report.

[0048] To achieve the above-mentioned purpose, another aspect of the embodiment of the present application provides a tire handling performance index coefficient automatic generation system, comprising:

[0049] The first module is used to generate a tire dynamics model using vehicle dynamics simulation software to obtain a model file;

[0050] The second module is used to obtain the load parameters input by the user; wherein the load parameters include the front axle load and the rear axle load;

[0051] A third module is used to read the model file and obtain a first calculation coefficient of the tire from the model file;

[0052] A fourth module is used to substitute the first calculation coefficient into the magic formula to obtain a first fitting function;

[0053] A fifth module is used to call the first fitting function, calculate the force and moment of each working condition according to the load parameter, and obtain a first calculation result;

[0054] A sixth module, configured to calculate the tire handling index coefficient under each of the working conditions by using an index calculation formula according to the first calculation result and the load parameter;

[0055] The seventh module is used to output the tire handling index coefficient to a preset result file and generate a tire handling performance index coefficient result report.

[0056] To achieve the above-mentioned purpose, another aspect of an embodiment of the present application provides an electronic device, the electronic device comprising a memory and a processor, the memory storing a computer program, and the processor implementing the above-mentioned method when executing the computer program.

[0057] To achieve the above objective, another aspect of an embodiment of the present application provides a computer-readable storage medium, wherein the computer-readable storage medium stores a computer program, and when the computer program is executed by a processor, the method described above is implemented.

[0058] The embodiments of the present application include at least the following beneficial effects: The present application provides a method and system for automatically generating tire handling performance index coefficients, which reads the first calculation coefficient in the tire dynamics model file, and then uses the magic formula to fit the forces and moments under various working conditions according to the load parameters input by the user and the first calculation coefficient read. The fitting results are calculated according to the formulas of each index coefficient, and output to the preset result file to form a report, which can accurately and efficiently generate tire handling performance index coefficients to improve tire modeling standardization. BRIEF DESCRIPTION OF THE DRAWINGS

[0059] The accompanying drawings are used to provide further understanding of the technical solution of the present application and constitute a part of the specification. Together with the embodiments of the present application, they are used to explain the technical solution of the present application and do not constitute a limitation on the technical solution of the present application.

[0060] Figure 1 It is a step diagram of a method and system method for automatically generating a tire handling performance index coefficient provided in an embodiment of the present application;

[0061] Figure 2is a schematic diagram of the lateral force calculation coefficient in the model file provided in the embodiment of the present application;

[0062] Figure 3 is a schematic diagram of the calculation coefficient of the aligning torque in the model file provided in the embodiment of the present application;

[0063] Figure 4 It is a schematic diagram of a page for a user to input load parameters provided in an embodiment of the present application;

[0064] Figure 5 It is a schematic diagram of an Excel file of a tire handling performance index coefficient result report provided in an embodiment of the present application;

[0065] Figure 6 It is a module schematic diagram of a tire handling performance index coefficient automatic generation system provided in an embodiment of the present application;

[0066] Figure 7 It is a schematic diagram of the hardware structure of the electronic device provided in the embodiment of the present application. DETAILED DESCRIPTION

[0067] In order to make the purpose, technical solutions and advantages of the present application clearer, the present application is further described in detail below in conjunction with the accompanying drawings and examples. It should be understood that the specific embodiments described herein are only used to explain the present application and are not intended to limit the present application. When the following description refers to the drawings, unless otherwise indicated, the same numbers in different drawings represent the same or similar elements. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with the embodiments of the present application. They are only examples of devices and methods consistent with some aspects of the embodiments of the present application as detailed in the attached claims.

[0068] Although the functional modules are divided in the system schematic diagram and the logical order is shown in the flowchart, in some cases, the steps shown or described may be performed in a different order than the module division in the system or the order in the flowchart. The terms "first / S100", "second / S200", etc. in the specification, claims and the above drawings are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence.

[0069] It is understood that the terms "first", "second", etc. used in this application can be used to describe various concepts in this article, but unless otherwise specified, these concepts are not limited by these terms. These terms are only used to distinguish one concept from another concept. For example, without departing from the scope of the embodiment of the present application, the first information may also be referred to as the second information, and similarly, the second information may also be referred to as the first information. Depending on the context, the words "if" and "if" as used herein can be interpreted as "at the time of" or "when" or "in response to determination".

[0070] The terms "at least one", "multiple", "each", "any", etc. used in this application, at least one includes one, two or more, multiple includes two or more, each refers to each of the corresponding multiple, and any refers to any one of the multiple.

[0071] Reference to "embodiments" herein means that a particular feature, structure, or characteristic described in conjunction with the embodiments may be included in at least one embodiment of the present application. The appearance of the phrase in various locations in the specification does not necessarily refer to the same embodiment, nor is it an independent or alternative embodiment that is mutually exclusive with other embodiments. It is explicitly and implicitly understood by those skilled in the art that the embodiments described herein may be combined with other embodiments.

[0072] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art to which this application belongs. The terms used herein are only for the purpose of describing the embodiments of this application and are not intended to limit this application.

[0073] As cars become the main target market for tires, tires, as the source of vehicle control force, have received more and more attention. As the only part of the vehicle in contact with the road, tires not only bear the weight of the car, but also transmit the force generated by the road during the process of forming. The handling performance of tires directly affects the handling stability of the vehicle. Therefore, it is important to study the handling stability index of tires.

[0074] In the related technology, when calculating the handling stability index coefficient of a tire, the data processing of forces and moments of dozens of working conditions is involved. Different loads and side slip angle conditions are manually input, and then the TDFT tool of the ADAMS software is used to fit the lateral force and the restoring moment. Then, the formula is used for calculation. This processing method is often time-consuming and requires about 30 minutes. When the analysis task is large, it will consume more manpower and time, and sometimes manual operation errors will lead to calculation errors.

[0075] In view of this, an embodiment of the present application provides a method and system for automatically generating tire handling performance index coefficients. The solution automatically reads the first calculation coefficient in the tire dynamics model file, and then uses the magic formula to fit the forces and moments under various working conditions according to the load parameters input by the user and the first calculation coefficient read. The fitting results are calculated according to the formulas of each index coefficient, and output to the preset result file to form a report, which can accurately and efficiently generate tire handling performance index coefficients to improve tire modeling standardization.

[0076] The embodiments of the present application provide a method and system method for automatically generating a tire handling performance index coefficient, which relates to the field of computer technology. The method and system method for automatically generating a tire handling performance index coefficient provided in the embodiments of the present application can be applied to a terminal, can also be applied to a server, and can also be software running in a terminal or a server. In some embodiments, the terminal can be a smart phone, a tablet computer, a laptop computer, a desktop computer, a smart speaker, a smart watch, and a vehicle-mounted terminal, etc., but is not limited to this; the server side can be configured as an independent physical server, or can be configured as a server cluster or distributed system composed of multiple physical servers, and can also be configured as a cloud server that provides basic cloud computing services such as cloud services, cloud databases, cloud computing, cloud functions, cloud storage, network services, cloud communications, middleware services, domain name services, security services, CDN, and big data and artificial intelligence platforms. The server can also be a node server in a blockchain network; the software can be an application that implements a method and system method for automatically generating a tire handling performance index coefficient, etc., but is not limited to the above forms.

[0077] The present application can be used in many general or special computer system environments or configurations. For example: personal computers, server computers, handheld or portable devices, tablet devices, multiprocessor systems, microprocessor-based systems, set-top boxes, programmable consumer electronics, network PCs, minicomputers, mainframe computers, distributed computing environments including any of the above systems or devices, etc. The present application can be described in the general context of computer-executable instructions executed by a computer, such as program modules. Generally, program modules include routines, programs, objects, components, data structures, etc. that perform specific tasks or implement specific abstract data types. The present application can also be practiced in distributed computing environments, in which tasks are performed by remote processing devices connected through a communication network. In a distributed computing environment, program modules can be located in local and remote computer storage media including storage devices.

[0078] Figure 1is an optional flow chart of a method and system method for automatically generating a tire handling performance index coefficient provided in an embodiment of the present application, Figure 1 The method may include but is not limited to steps S100 to S700.

[0079] Step S100, using vehicle dynamics simulation software to generate a tire dynamics model to obtain a model file.

[0080] Step S200, obtaining load parameters input by a user; wherein the load parameters include a front axle load and a rear axle load.

[0081] Step S300, reading the model file, and obtaining a first calculation coefficient of the tire from the model file.

[0082] Step S400: Substitute the first calculation coefficient into the magic formula to obtain a first fitting function.

[0083] Step S500, calling the first fitting function, calculating the force and moment of each working condition according to the load parameters, and obtaining a first calculation result.

[0084] Step S600: Calculate the tire handling index coefficient under each of the working conditions using an index calculation formula according to the first calculation result and the load parameter.

[0085] Step S700: output the tire handling index coefficient to a preset result file to generate a tire handling performance index coefficient result report.

[0086] In the step S100 to step S700 shown in the embodiment of the present application, the first calculation coefficient in the tire dynamics model file is automatically read, and then the magic formula is used to fit the forces and moments under various working conditions according to the load parameters input by the user and the first calculation coefficient read. The fitting results are calculated according to the formulas of various index coefficients, and the various handling index coefficients of the tire under various working conditions are output to the preset result file to form a report, which can accurately and efficiently generate the tire handling performance index coefficients to improve the standardization of tire modeling.

[0087] In some embodiments, step S100 may include but is not limited to the following steps S110 to S120:

[0088] Step S110, obtaining tire test data and tire specifications;

[0089] Step S120, based on the tdft tool of ADAMS software, generate the tire PAC2002 dynamic model according to the test data and the tire specifications to obtain a model file.

[0090] In some embodiments, step S300 may include but is not limited to the following steps S310 to S360:

[0091] Step S310, configuring a key tag string, and determining a key position of the model file according to the key tag string; wherein the key tag string includes a first tag string, a second tag string, a third tag string and a fourth tag string;

[0092] Step S320, continuing to read the model file from the key position corresponding to the first mark character string to obtain a first result character string, and performing character string segmentation and numerical conversion on the first result character string to obtain a tire radius parameter;

[0093] Step S330, continuing to read the model file from the key position corresponding to the second mark character string to obtain a second result character string, and performing character string segmentation and numerical conversion on the second result character string to obtain a tire standard load parameter;

[0094] Step S340, continue to read the model file from the key position corresponding to the fourth mark character string to obtain a fourth result character string, and perform character string segmentation and value conversion on the fourth result character string to obtain a plurality of return moment calculation coefficients;

[0095] Step S350, continuing to read the model file from the key position corresponding to the fourth mark character string to obtain a fourth result character string, and performing character string segmentation and value conversion on the fourth result character string to obtain a plurality of lateral force calculation coefficients;

[0096] Step S360: Using the tire radius parameter, the tire standard load parameter, the lateral force calculation coefficient and the self-aligning moment calculation coefficient as the first calculation coefficient of the tire.

[0097] In some embodiments, step S400 includes but is not limited to the following steps S410 to S450:

[0098] Step S410, obtaining a lateral force calculation coefficient and a self-aligning moment calculation coefficient from the first calculation coefficient;

[0099] Step S420, constructing a magic formula;

[0100] Step S430, using the slip angle, longitudinal slip rate, roll angle and target load as input variables, constructing a lateral force fitting function in MATLAB software; wherein the lateral force fitting function is obtained by substituting the lateral force calculation coefficient into the magic formula;

[0101] Step S440, using the sideslip angle, the longitudinal slip rate, the roll angle and the target load as input variables, constructing a self-aligning moment fitting function in MATLAB software; wherein the self-aligning moment fitting function is obtained by substituting the self-aligning moment calculation coefficient into the magic formula;

[0102] Step S450: taking the lateral force fitting function and the self-aligning moment fitting function as a first fitting function.

[0103] In step S400 of some embodiments, the first fitting function includes a lateral force fitting function and a aligning moment fitting function, wherein:

[0104] The expression of the lateral force fitting function is:

[0105] F y =F y0 (α,γ,F z );

[0106]

[0107] The expression of the aligning moment fitting function is:

[0108] M′ z =M z0 (α,γ,F z );

[0109] M z0 =-t·F y0 +M zr ;

[0110] t(α t )=D t cos[C t arc tan{B t α t -E t (B t α t -arc tan(B t α t ))}]cos(α);

[0111] Among them, F y is the lateral force obtained by fitting; M′ z is the fitting return torque; F y0 is the lateral force fitting function α, α y and α t is the slip angle; γ is the roll angle; F z is the load; D y and D t is the peak factor; C y and Ct is the shape factor; B y and B t is the stiffness factor; B y and E t Curvature factor; It is the lateral force caused by the longitudinal slip rate.

[0112] In step S600 of some embodiments, the index coefficient calculation formula includes a sideslip coefficient index coefficient calculation formula, a load transfer sensitivity index coefficient calculation formula, and a load sensitivity index coefficient calculation formula, wherein:

[0113] The calculation formula of the cornering coefficient index coefficient is:

[0114]

[0115] The load transfer sensitivity index coefficient calculation formula is:

[0116]

[0117] The load sensitivity index coefficient calculation formula is:

[0118]

[0119] Among them, F(α) is the sideslip coefficient index coefficient; Fy is the lateral force fitting function; α is the sideslip angle; Fz is the load parameter; G(Fz, α) is the load transfer sensitivity index coefficient; Δ is the left and right load transfer amount of the front axle or rear axle; H(Fz, α) is the load sensitivity index coefficient.

[0120] In some embodiments, step S700 includes but is not limited to the following steps S710 to S720:

[0121] Step S710, creating an Excel file in the target directory to obtain a preset result file;

[0122] Step S720, calling the excel file reading function of MATLAB, outputting the calculation result to the preset result file, and saving the file to obtain a tire handling performance index coefficient result report.

[0123] Below, in conjunction with a specific example of a scenario application in which a tire handling performance index coefficient is automatically calculated and generated, the solution of the embodiment of the present application is described in detail and explained:

[0124] In an embodiment of the present application, a method and system method for automatically generating a tire handling performance index coefficient are provided. The method can be applied to automatically generate a tire handling performance index coefficient, and can be specifically implemented as follows:

[0125] Taking the tire specification 205 / 55R16 as an example, using the six-component force and other test data of the tire, the ADAMS-based tdft tool is used to generate the tire PAC2002 dynamic model and obtain the model file. Figure 2 and Figure 3 The model file includes important parameters such as LATERAL_COEFFICIENTS (lateral force calculation coefficient) and ALIGNING_COEFFICIENTS (aligning moment calculation coefficient).

[0126] Further, refer to Figure 4 As shown, the load parameters input by the user, namely the front axle load and the rear axle load, are obtained for subsequent calculations. After clicking the control for calculating the handling stability parameters, the tire handling performance index can be automatically calculated.

[0127] Furthermore, various parameters of the tire dynamics model PAC2002 are automatically read.

[0128] A MATLAB sub-function Parameter for reading tire parameters is established, the PAC2002 model file is read in, and then the tire radius parameter, tire standard load parameter, lateral force calculation coefficient and self-aligning moment calculation coefficient are read as the first calculation coefficient.

[0129] In the step of reading the tire radius parameters, first find the "[DIMENSION]" string position in the model file as the key position, and continue reading until the string line containing the tire radius is found. The string content is "UNLOADED_RADIUS=xxxx$Free tyre radius". Assign the string to the variable data, split the data according to spaces, and get the string "xxxx" containing only the tire radius value. Convert it into a numerical value through the str2double command and store it in the UNLOADED_RADIUS variable to get the tire radius parameter.

[0130] In the step of reading the tire load parameters, first find the "[VERTICAL]" string position in the model file as the key position, and continue reading until the string row containing the standard tire load is found, the content is "FNOMIN=xxxx$Nominal wheel load", and the tire load parameters are obtained using the same data processing method as the above-mentioned reading of the tire radius parameters and stored in the FNOMIN variable.

[0131] In the step of reading the lateral force calculation coefficient, first find the "[LATERAL_COEFFICIENTS]" string position in the model as the key position, continue reading, and use the same method as above to obtain 39 parameters related to the lateral force in turn, and store them in the preset variables PCY1, PDY1, PDY2, PDY3, PEY1, PEY2, PEY3, PEY4, PKY1, PKY2, PKY3, PHY1, PHY2, PHY3, PVY1, PVY2, PVY3, PVY4, PPY1, PPY2, PPY3, PPY4, RBY1, RBY2, RBY3, RCY1, RHY1, RVY1, RVY2, RVY3, RVY4, RVY5, RVY6, REY1, REY2, RHY2, PTY1, PTY2, PTY3, to form a group of lateral force calculation coefficients.

[0132] (5) Read the parameters of the aligning torque. Find the position of the string "[ALIGNING_COEFFICIENTS]" in the model as the key position, continue reading, and use the same method as above to obtain 33 parameters related to the aligning torque in turn, and store them in the preset variables QBZ1, QBZ2, QBZ3, QBZ4, QBZ5, QBZ9, QBZ10, QCZ1, QDZ1, QDZ2, QDZ3, QDZ4, QDZ6, QDZ7, QDZ8, QDZ9, QEZ1, QEZ2, QEZ3, QEZ4, QEZ5, QHZ1, QHZ2, QHZ3, QHZ4, QPZ1, QPZ2, SSZ1, SSZ2, SSZ3, SSZ4, QTZ1, and MBELT to form a group of aligning torque calculation coefficients.

[0133] By reading the above-mentioned model file, the main parameters (first calculation coefficients) used to calculate the tire handling performance index coefficients are obtained, and the parameters are stored in various variables.

[0134] Furthermore, the magic formula is used to fit the lateral force and righting moment under various working conditions through MATLAB.

[0135] Specifically, taking tire lateral force fitting as an example, a MATLAB sub-function FyFit (SA, SR, IA, Fz) for lateral force fitting is established, and the input variables include the tire's sideslip angle SA, longitudinal slip rate SR, roll angle IA, and load Fz.

[0136] The tire parameter reading sub-function Parameter constructed above is called to obtain the first calculation coefficient of each working condition.

[0137] The magic formula is used to fit the lateral force Fy. The lateral force fitting formula is as follows:

[0138] F y =F y0 (α,γ,F z );

[0139]

[0140] Based on the tire PAC2002 dynamic model, the coefficients in the formula can be obtained by the following calculation:

[0141] α y =α+S Hy ;

[0142] γ y =γ·λ γy ;

[0143] C y =P Cy1 ·λ Cy ;

[0144] D y =μ y ·F z ζ2;

[0145]

[0146] E y =(p Ey1 +p Ey2 df z )·{1-(p Ey3 +p Ey4 γ y )sgn(α y )}·λ Ey with E y ≤1;

[0147]

[0148] K y =K y0 ·(1-p Ky3 |γ y |)·ζ3;

[0149] B y =K y / (C y D y );

[0150]

[0151] The fitting formula of the return torque is:

[0152] M′ z =Mz0 (α,γ,F z );

[0153] M z0 =-t·F y0 +M zr ;

[0154] t(α t )=D t cos[C t arc tan{B t α t -E t (B t α t -arc tan(B t α t ))}]cos(α);

[0155] In the above formula, F y is the lateral force obtained by fitting; M′ z is the fitting return torque; F y0 is the lateral force fitting function; α, α y and α t is the slip angle; γ is the roll angle; F z is the load; D y and D t is the peak factor; C y and C t is the shape factor; B y and B t is the stiffness factor; E y and E t Curvature factor; is the lateral force caused by the longitudinal slip rate; the λ parameter is a scaling factor, which is set to 1 by default. Cy1 The parameters correspond to the tire lateral force calculation coefficient variable PCY1 obtained above, etc. Through the above lateral force fitting formula, a MATLAB sub-function is used to construct a lateral force fitting function.

[0156] For the self-aligning moment, a similar method as above is used to establish the MATLAB sub-function MzFit for self-aligning moment fitting. The same method as the lateral force is used to substitute the parameters in the tire PAC2002 dynamic model into the magic formula of the self-aligning moment to obtain the self-aligning moment fitting function. The above lateral force fitting function and self-aligning moment fitting function can be collectively referred to as the first fitting function.

[0157] Furthermore, the lateral force and the righting moment under various working conditions are fitted by the first fitting function, and various control index coefficients are automatically calculated according to the index coefficient calculation formula.

[0158] Specifically, the tire handling index coefficients include a cornering coefficient index coefficient, a load transfer sensitivity index coefficient, a load sensitivity index coefficient, and a aligning torque index coefficient.

[0159] In some embodiments, the side slip coefficient index coefficient can be represented by F, and there are 8 coefficients in total, including coefficients under 8 working conditions composed of 2 loads (front axle load F1, rear axle load F2) and 4 side slip angles (1 degree, 2 degrees, 4 degrees, and 8 degrees). Taking the first side slip coefficient F_f(1°) as an example (F represents the side slip coefficient, f represents the front axle, and 1° represents the side slip angle), call the lateral force sub-function FyFit(SA, SR, IA, Fz), and define the variable SA as -15°:15°, SR is 0, IA is 0, and Fz is the front axle load F1. You can get the value of the lateral force Fy changing with the side slip angle SA under the load F1, extract the lateral force when the side slip angle is -1° and 1°, take the absolute value of the average value, and divide it by the front axle load F1 to get the side slip index coefficient F_f(1°). The calculation formula of the side slip coefficient index coefficient is:

[0160]

[0161] Among them, F(α) is the index coefficient of the sideslip coefficient; Fy is the lateral force fitting function; α is the sideslip angle; Fz is the load parameter.

[0162] The calculation process of F_f(2°), F_f(4°), and F_f(8°) is the same as that of F_f(1°). The average and absolute values ​​of the lateral forces at the sideslip angles of ±2°, ±4°, and ±8° are extracted respectively, and then divided by the front axle load F1. The side slip index coefficient of the rear axle load is used to call the lateral force sub-function FyFit again to obtain the value of the lateral force Fy changing with the sideslip angle SA under the rear axle load F2. F_r(2°), F_r(2°), F_r(4°), and F_r(8°) respectively extract the average and absolute values ​​of the lateral forces at the sideslip angles of ±1°, ±2°, ±4°, and ±8°, and then divide by the rear axle load F2.

[0163] In some embodiments, the load transfer sensitivity index coefficient can be represented by G, and there are 6 coefficients in total, including coefficients under 6 working conditions composed of 2 loads (front axle load F1, rear axle load F2) and 3 sideslip angles (1 degree, 2 degrees, and 4 degrees). Taking the first sideslip coefficient G_f(1°) as an example (G represents the load transfer sensitivity index coefficient, f represents the front axle, and 1° represents the sideslip angle), the lateral force sub-function FyFit(SA,SR,IA,Fz) is called, and the variable SA is defined as -15°: 15°, S R is 0, IA is 0, and Fz is the front axle load F1. Then, the value of the lateral force Fy under load F1 changing with the slip angle SA can be obtained. In addition, the sub-function FyFit needs to be called again to extract the value of the lateral force changing with the slip angle SA under 0.8Fz and 1.2Fz. Finally, the lateral force at the slip angle of -1° and 1° under 3 loads of 0.8Fz, Fz, and 1.2Fz is obtained. The absolute value of the average value is taken and then substituted into the following formula to obtain the load transfer sensitivity index coefficient G_f(1°). The calculation formula of the load transfer sensitivity index coefficient is:

[0164]

[0165] Where Δ is the load transfer amount of the front or rear axle, which is determined by the selected slip angle α. When α is 1 degree, 2 degrees, and 4 degrees, Δ is 0.2, 0.5, and 0.65, respectively. The calculation process of G_f(2°) and G_f(4°) is the same as that of G_f(1°), except that the lateral forces under different loads and slip angles are taken according to the requirements of the formula. The load transfer sensitivity index coefficients of the rear axle load G_r(1°), G_r(2°), and G_r(4°) are used again to call the lateral force sub-function FyFit to obtain the values ​​of the lateral force Fy changing with the slip angle SA under the rear axle load F2 and the rear axle load required by the formula multiplied by different coefficients, and then substitute them into the formula to complete the calculation.

[0166] In some embodiments, the load sensitivity index coefficient can be represented by H, and there are 2 of them, including the coefficients under two working conditions composed of two loads (front axle load F1, rear axle load F2) and 1 side slip angle (1 degree). Taking the first load sensitivity index coefficient H_f(1°) as an example (H represents the load sensitivity index, f represents the front axle, and 1° represents the side slip angle), calling the lateral force sub-function FyFit(SA,SR,IA,Fz), the variable SA is defined as -15°:15°, SR is 0, IA is 0, and Fz is the front axle load F1, the value of the lateral force Fy under the load F1 changing with the side slip angle SA can be obtained, calling the lateral force sub-function FyFit, the value of the lateral force under the load of 0.8F1 changing with the side slip angle, extracting the lateral forces under the two loads when the side slip angles are -1° and 1°, subtracting the absolute values ​​of the average values, and then dividing by the front axle load F1*0.2, the side slip index coefficient H_f(1°) can be obtained. The calculation formula of load sensitivity index coefficient is:

[0167]

[0168] The calculation process of the load sensitivity index coefficient H_r(1°) is the same as that of H_f(1°). The lateral force sub-function FyFit is called again to obtain the value of the lateral force Fy changing with the sideslip angle SA under the two loads of rear axle load F2 and 0.8F2. The lateral force under the two loads when the sideslip angle is -1° and 1° is extracted, the absolute value of the average value is subtracted, and then divided by the rear axle load F2*0.2.

[0169] In some embodiments, the righting moment index coefficient can be represented by AT, and there is a total of 1, which is the coefficient AT_f(1°) obtained under the front axle load F1 and the sideslip angle of 1 degree, where AT represents the righting moment index coefficient, f represents the front axle, and 1° represents the sideslip angle. The righting moment sub-function MzFit(SA,SR,IA,Fz) is called, and the variable SA is defined as -15°:15°, SR is 0, IA is 0, and Fz is the front axle load F1. The value of the righting moment Mz under the load F1 that changes with the sideslip angle SA can be obtained. The righting moment when the sideslip angle is -1° and 1° is extracted, the absolute value of the average value is taken, and then divided by the front axle load F1 to obtain the righting moment index coefficient AT_f(1°). The calculation formula of the righting moment index coefficient is:

[0170]

[0171] Among them, M z (F z , α) represents the self-aligning torque.

[0172] After completing the calculation of the above 17 tire handling performance index coefficients, create an Excel file in the specified directory, use the MATLAB function to read the Excel file, output the specified coefficients to the specified Excel table location, save and exit, and complete the automatic generation of the Excel report. The generated tire handling performance index coefficient result report is as follows: Figure 5 shown.

[0173] In some embodiments, the longitudinal force may be fitted in a similar manner to calculate other tire index coefficients, which will not be described in detail here.

[0174] The embodiments of the present application have at least the following beneficial effects: by automatically reading various parameters in the tire dynamics model file, and then using the modulus formula through MATLAB's forces and moments under various working conditions, the corresponding load, force or moment under the sideslip angle is calculated according to the various index coefficient formulas, and the various handling index coefficients are automatically calculated through the program and output to a preset result document to form a report. It can automatically generate several accurate tire handling performance index coefficients in a short time, greatly improving the calculation efficiency.

[0175] See also Figure 6 The embodiment of the present application also provides a tire handling performance index coefficient automatic generation system, which can implement the above-mentioned tire handling performance index coefficient automatic generation method and system method, and the system includes:

[0176] The first module 101 is used to generate a tire dynamics model using vehicle dynamics simulation software to obtain a model file;

[0177] The second module 102 is used to obtain the load parameters input by the user; wherein the load parameters include the front axle load and the rear axle load;

[0178] The third module 103 is used to read the model file and obtain the first calculation coefficient of the tire from the model file;

[0179] The fourth module 104 is used to substitute the first calculation coefficient into the magic formula to obtain a first fitting function;

[0180] The fifth module 105 is used to call the first fitting function, calculate the force and moment of each working condition according to the load parameter, and obtain a first calculation result;

[0181] A sixth module 106 is used to calculate the tire handling index coefficient under each of the working conditions by using an index calculation formula according to the first calculation result and the load parameter;

[0182] The seventh module 107 is used to output the tire handling index coefficient to a preset result file to generate a tire handling performance index coefficient result report.

[0183] It can be understood that the contents of the above method embodiments are all applicable to the present system embodiments, the functions specifically implemented by the present system embodiments are the same as those of the above method embodiments, and the beneficial effects achieved are also the same as those achieved by the above method embodiments.

[0184] The embodiment of the present application also provides an electronic device, the electronic device includes a memory and a processor, the memory stores a computer program, and the processor implements the above-mentioned tire handling performance index coefficient automatic generation method and system method when executing the computer program. The electronic device can be any intelligent terminal including a tablet computer, a car computer, etc.

[0185] It can be understood that the contents of the above method embodiments are all applicable to the present device embodiments, the functions specifically implemented by the present device embodiments are the same as those of the above method embodiments, and the beneficial effects achieved are also the same as those achieved by the above method embodiments.

[0186] See also Figure 7 , Figure 7 The hardware structure of an electronic device of another embodiment is illustrated, and the electronic device includes:

[0187] The processor 201 may be implemented by a general-purpose CPU (Central Processing Unit), a microprocessor, an application-specific integrated circuit (ASIC), or one or more integrated circuits, and is used to execute relevant programs to implement the technical solutions provided in the embodiments of the present application;

[0188] The memory 202 can be implemented in the form of a read-only memory (ROM), a static storage device, a dynamic storage device, or a random access memory (RAM). The memory 202 can store an operating system and other application programs. When the technical solution provided in the embodiment of this specification is implemented by software or firmware, the relevant program code is stored in the memory 202, and the processor 201 calls and executes a method and system method for automatically generating a tire handling performance index coefficient in the embodiment of this application;

[0189] Input / output interface 203, used to implement information input and output;

[0190] The communication interface 204 is used to realize the communication interaction between the device and other devices. The communication can be realized through a wired manner (such as USB, network cable, etc.) or a wireless manner (such as mobile network, WIFI, Bluetooth, etc.);

[0191] Bus 205 , which transmits information between various components of the device (e.g., processor 201 , memory 202 , input / output interface 203 , and communication interface 204 );

[0192] The processor 201 , the memory 202 , the input / output interface 203 and the communication interface 204 are connected to each other in communication within the device via the bus 205 .

[0193] An embodiment of the present application also provides a computer-readable storage medium, which stores a computer program. When the computer program is executed by a processor, the above-mentioned method and system method for automatically generating tire handling performance index coefficients are implemented.

[0194] It can be understood that the contents of the above method embodiments are all applicable to the present storage medium embodiments, the functions specifically implemented by the present storage medium embodiments are the same as those of the above method embodiments, and the beneficial effects achieved are also the same as those achieved by the above method embodiments.

[0195] The memory, as a non-transient computer-readable storage medium, can be used to store non-transient software programs and non-transient computer executable programs. In addition, the memory may include a high-speed random access memory, and may also include a non-transient memory, such as at least one disk storage device, a flash memory device, or other non-transient solid-state storage device. In some embodiments, the memory may optionally include a memory remotely disposed relative to the processor, and these remote memories may be connected to the processor via a network. Examples of the above-mentioned network include, but are not limited to, the Internet, an intranet, a local area network, a mobile communication network, and combinations thereof.

[0196] The embodiments described in the embodiments of the present application are intended to more clearly illustrate the technical solutions of the embodiments of the present application and do not constitute a limitation on the technical solutions provided in the embodiments of the present application. Those skilled in the art will appreciate that with the evolution of technology and the emergence of new application scenarios, the technical solutions provided in the embodiments of the present application are also applicable to similar technical problems.

[0197] Those skilled in the art will appreciate that the technical solutions shown in the figures do not constitute a limitation on the embodiments of the present application, and may include more or fewer steps than shown in the figures, or a combination of certain steps, or different steps.

[0198] The system embodiments described above are merely illustrative, and the units described as separate components may or may not be physically separated, that is, they may be located in one place or distributed on multiple network units. Some or all of the modules may be selected according to actual needs to achieve the purpose of the present embodiment.

[0199] Those skilled in the art will appreciate that all or some of the steps in the methods disclosed above, and the functional modules / units in the systems and devices may be implemented as software, firmware, hardware, or a suitable combination thereof.

[0200] The terms "first", "second", "third", "fourth", etc. (if any) in the specification 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 sequence. 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 an order 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.

[0201] It should be understood that in the present application, "at least one (item)" means one or more, and "plurality" means two or more. "And / or" is used to describe the association relationship of associated objects, indicating that three relationships may exist. For example, "A and / or B" can mean: only A exists, only B exists, and A and B exist at the same time, where A and B can be singular or plural. The character " / " generally indicates that the objects associated before and after are in an "or" relationship. "At least one of the following" or similar expressions refers to any combination of these items, including any combination of single or plural items. For example, at least one of a, b or c can mean: a, b, c, "a and b", "a and c", "b and c", or "a and b and c", where a, b, c can be single or multiple.

[0202] In the several embodiments provided in the present application, it should be understood that the disclosed devices and methods can be implemented in other ways. For example, the system embodiments described above are only schematic. For example, the division of the above units is only a logical function division. There may be other division methods in actual implementation, 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 an indirect coupling or communication connection through some interfaces, devices or units, which can be electrical, mechanical or other forms.

[0203] The units described above as separate components may or may not be physically separated, and the components shown as units may or may not be physical units, that is, they may be located in one place or distributed on multiple network units. Some or all of the units may be selected according to actual needs to achieve the purpose of the solution of this embodiment.

[0204] In addition, each functional unit in each embodiment of the present application may be integrated into one processing unit, or each unit may exist physically separately, or two or more units may be integrated into one unit. The above-mentioned integrated unit may be implemented in the form of hardware or in the form of software functional units.

[0205] 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 prior art, or all or part of the technical solution can be embodied in the form of a software product, and the computer software product is stored in a storage medium, including multiple instructions to enable a computer device (which can be a personal computer, server, or network device, etc.) to execute all or part of the steps of the methods of various embodiments of the present application. The aforementioned storage medium includes: U disk, mobile hard disk, read-only memory (Read-Only Memory, referred to as ROM), random access memory (Random Access Memory, referred to as RAM), disk or optical disk and other media that can store programs.

[0206] The preferred embodiments of the present invention are described above with reference to the accompanying drawings, but the scope of the rights of the present invention is not limited thereto. Any modification, equivalent substitution and improvement made by a person skilled in the art without departing from the scope and essence of the present invention should be within the scope of the rights of the present invention.

Claims

1. A method and system method for automatically generating tire handling performance index coefficients, characterized in that: The following steps are involved: Generate a tire dynamics model using vehicle dynamics simulation software to obtain a model file; Obtaining load parameters input by a user; wherein the load parameters include front axle load and rear axle load; Reading the model file, and acquiring a first calculation coefficient of the tire from the model file; Substituting the first calculation coefficient into the magic formula to obtain a first fitting function; Calling the first fitting function, calculating the force and moment of each working condition according to the load parameters, and obtaining a first calculation result; Calculating the tire handling index coefficient under each of the working conditions by using an index calculation formula according to the first calculation result and the load parameter; The tire handling index coefficient is output to a preset result file to generate a tire handling performance index coefficient result report.

2. The method according to claim 1, characterized in that The method of using vehicle dynamics simulation software to generate a tire dynamics model and obtain a model file includes the following steps: Obtain tire test data and tire specifications; Based on the tdft tool of ADAMS software, a tire PAC2002 dynamic model is generated according to the test data and the tire specifications to obtain a model file.

3. The method according to claim 1, characterized in that The step of reading the model file and obtaining the first calculation coefficient of the tire from the model file comprises the following steps: Configuring a key tag string, and determining a key position of the model file according to the key tag string; wherein the key tag string includes a first tag string, a second tag string, a third tag string and a fourth tag string; Continue reading the model file from the key position corresponding to the first mark character string to obtain a first result character string, and perform character string segmentation and numerical conversion on the first result character string to obtain a tire radius parameter; Continue reading the model file from the key position corresponding to the second mark character string to obtain a second result character string, and perform character string segmentation and numerical conversion on the second result character string to obtain a tire standard load parameter; Continue reading the model file from the key position corresponding to the third mark character string to obtain a third result character string, and perform character string segmentation and numerical conversion on the third result character string to obtain a plurality of lateral force calculation coefficients; Continue reading the model file from the key position corresponding to the fourth mark character string to obtain a fourth result character string, and perform character string segmentation and value conversion on the fourth result character string to obtain a plurality of self-aligning torque calculation coefficients; The tire radius parameter, the tire standard load parameter, the lateral force calculation coefficient and the self-aligning moment calculation coefficient are used as the first calculation coefficient of the tire.

4. The method according to claim 1, characterized in that: Substituting the first calculation coefficient into the magic formula to obtain a first fitting function comprises the following steps: Obtaining a lateral force calculation coefficient and a self-aligning moment calculation coefficient from the first calculation coefficient; Construct the magic formula; Taking the slip angle, longitudinal slip rate, roll angle and target load as input variables, a lateral force fitting function is constructed in MATLAB software; wherein the lateral force fitting function is obtained by substituting the lateral force calculation coefficient into the magic formula; Taking the sideslip angle, the longitudinal slip rate, the roll angle and the target load as input variables, a self-aligning moment fitting function is constructed in MATLAB software; wherein the self-aligning moment fitting function is obtained by substituting the self-aligning moment calculation coefficient into the magic formula; The lateral force fitting function and the self-aligning moment fitting function are used as the first fitting function.

5. The method according to claim 1, characterized in that The first fitting function includes a lateral force fitting function and a aligning moment fitting function, wherein: The expression of the lateral force fitting function is: F y =F y0 (a, c, F z ); F y0 =D y sin[C y silver{B y α y -AND y (B y α y -arctane(B y α y ))}]+S Vy ; The expression of the aligning moment fitting function is: M′ z =M z0 (a, c, F z ); M z0 =-t·F y0 +M zr ; t(a t )=D t cos[C t arctan{B t a t -E t (B t a t -arctan(B t a t ))}]cos(α); Among them, F y is the lateral force obtained by fitting; M′ z is the fitting return torque; F y0 is the lateral force fitting function; α, α y and α t is the slip angle; γ is the roll angle; F z is the load; D y and D t is the peak factor; C y and C t is the shape factor; B y and B t is the stiffness factor; E y and E t Curvature factor; S Vy It is the lateral force caused by the longitudinal slip rate.

6. The method according to claim 1, characterized in that The index coefficient calculation formula includes the side slip coefficient index coefficient calculation formula, the load transfer sensitivity index coefficient calculation formula, and the load sensitivity index coefficient calculation formula, wherein: The calculation formula of the cornering coefficient index coefficient is: The load transfer sensitivity index coefficient calculation formula is: The load sensitivity index coefficient calculation formula is: Among them, F(α) is the sideslip coefficient index coefficient; Fy is the lateral force fitting function; α is the sideslip angle; Fz is the load parameter; G(Fz, α) is the load transfer sensitivity index coefficient; Δ is the left and right load transfer amount of the front axle or rear axle; H(Fz, α) is the load sensitivity index coefficient.

7. The method according to claim 1, characterized in that The step of outputting the tire handling index coefficient to a preset result file to generate a tire handling performance index coefficient result report comprises the following steps: Create an Excel file in the target directory and get the preset result file; The excel file reading function of MATLAB is called to output the calculation result to the preset result file, and the file is saved to obtain a tire handling performance index coefficient result report.

8. A tire handling performance index coefficient automatic generation system, characterized in that: include: The first module is used to generate a tire dynamics model using vehicle dynamics simulation software to obtain a model file; The second module is used to obtain the load parameters input by the user; wherein the load parameters include the front axle load and the rear axle load; A third module is used to read the model file and obtain a first calculation coefficient of the tire from the model file; A fourth module is used to substitute the first calculation coefficient into the magic formula to obtain a first fitting function; A fifth module is used to call the first fitting function, calculate the force and moment of each working condition according to the load parameter, and obtain a first calculation result; A sixth module, configured to calculate the tire handling index coefficient under each of the working conditions by using an index calculation formula according to the first calculation result and the load parameter; The seventh module is used to output the tire handling index coefficient to a preset result file and generate a tire handling performance index coefficient result report.

9. An electronic device, characterized in that: including a processor and a memory; The memory is used to store programs; The processor executes the program to implement the method according to any one of claims 1 to 7.

10. A computer storage medium storing a program executable by a processor, characterized in that: The program executable by the processor is used to implement the method according to any one of claims 1 to 7 when executed by the processor.

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