Method and device for determining residual aligning torque of tire pattern and electronic equipment

Abstract

The invention discloses a method and a device for determining residual aligning torque of a tire pattern and electronic equipment. The method comprises the steps that design parameters of a target tire are obtained, and the design parameters comprise pattern parameters used for reflecting geometrical characteristics of tire patterns of the target tire; determining the lateral force and the aligning torque of the tread pattern corresponding to the design parameters under the plurality of slip angles; the lateral force and the aligning torque are linearly fitted with the slip angle to obtain a fitting result, and the fitting result is used for reflecting the sensitivity degree of the lateral force and the aligning torque to the change of the slip angle; and under the condition that the lateral force is zero, determining a target aligning torque according to a fitting result, and taking the target aligning torque as the residual aligning torque of the tire pattern. According to the method and the device, the technical problem that the influence of a single pattern design factor on the residual aligning torque cannot be directly obtained through simulation when the residual aligning torque result of the tire is simulated by adopting a simulation method in related technologies is solved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of tire mechanical performance evaluation, in particular to a method and device for determining residual cornering force of tire pattern and electronic equipment. BACKGROUND

[0002] Tire is an important part of automobile, and the design of tire pattern directly affects the handling performance, safety and driving comfort of vehicle. In the field of tire design, residual cornering force is a key performance indicator, which reflects the ability of tire to automatically restore straight driving trend under small angle side slip. However, the related technology simulates the residual cornering force of tire by simulation method, but the simulation cannot directly obtain the influence of single pattern design factor on residual cornering force, and cannot meet the demand of tire design engineers to quickly and accurately predict the performance of pattern residual cornering force in the early design stage.

[0003] At present, no effective solution has been proposed for the above problems. SUMMARY

[0004] The embodiments of the present application provide a method and device for determining residual cornering force of tire pattern and electronic equipment, so as to at least solve the technical problem that the related technology simulates the residual cornering force of tire by simulation method, but the simulation cannot directly obtain the influence of single pattern design factor on residual cornering force.

[0005] According to an aspect of the embodiments of the present application, a method for determining residual cornering force of tire pattern is provided, comprising: obtaining design parameters of a target tire, wherein the design parameters include pattern parameters for reflecting geometric characteristics of tire pattern of the target tire; determining lateral force and cornering force of tire pattern corresponding to the design parameters under a plurality of side slip angles; linearly fitting the lateral force and cornering force with the side slip angle to obtain fitting results, wherein the fitting results are used to reflect the sensitivity of the lateral force and cornering force to the change of side slip angle; determining a target cornering force according to the fitting results in the case that the lateral force is zero, and taking the target cornering force as the residual cornering force of tire pattern.

[0006] In some embodiments of the present application, the lateral force and the aligning moment of the tire pattern corresponding to the design parameters under a plurality of cornering angles are determined by: obtaining an inertia principal axis corresponding to a target block in the tire pattern, wherein the target block is any one of a plurality of blocks in the tire pattern on a footprint of the target tire, and the inertia moment of the target block is minimum when the target block rotates around the inertia principal axis; determining a first coordinate system corresponding to the inertia principal axis, and determining a first longitudinal force and a first lateral force of the target block in the first coordinate system; converting the first longitudinal force and the first lateral force into a second longitudinal force and a second lateral force in a second coordinate system, wherein the second coordinate system is a Cartesian coordinate system determined along a running direction of the target tire; and determining the lateral force and the aligning moment of the tire pattern according to the second longitudinal force, the second lateral force and the corresponding cornering angle of each block.

[0007] In some embodiments of the present application, the aligning moment of the tire pattern is determined according to the second longitudinal force, the second lateral force and the corresponding cornering angle of each block, by: obtaining a longitudinal deformation index of the target block, wherein the longitudinal deformation index is used to represent the compression or stretching deformation amount of the target block in the rolling direction of the tire; determining a trail of the target tire, wherein the trail is used to represent the vertical distance from the lateral force action point of the target tire to the center axis of the target tire; determining a moment length of the target block according to the longitudinal deformation index, the trail and the cornering angle, wherein the moment length is used to represent the vertical distance between the center of the target block and the center axis of the target tire; and determining the aligning moment corresponding to the moment length.

[0008] In some embodiments of the present application, the trail of the target tire is determined by: determining a third lateral force and a viscous aligning moment corresponding to a target area of the target tire, wherein the target area includes an area formed by the contact surface of the target tire and the road surface without slip; and determining the ratio of the third lateral force to the viscous aligning moment as the trail.

[0009] In some embodiments of the present application, the lateral force and the aligning moment are linearly fitted with the cornering angle to obtain a fitting result, by: linearly fitting a plurality of cornering angles with the corresponding lateral force and aligning moment to obtain a first fitting result and a second fitting result, wherein the first fitting result is used to reflect the sensitivity of the lateral force to the change of the cornering angle, and the second fitting result is used to reflect the sensitivity of the aligning moment to the change of the cornering angle.

[0010] In some embodiments of the present application, the target aligning moment is determined according to the fitting result when the lateral force is zero, and the target aligning moment is taken as the residual aligning moment of the tire pattern, comprising: determining the target side slip angle corresponding to the first fitting result when the lateral force is zero, wherein the target side slip angle is used to simulate the state of the target tire maintaining straight driving by the tire pattern without any external lateral force intervention; the target side slip angle is brought into the second fitting result for calculation to obtain the target aligning moment, and the target aligning moment is taken as the residual aligning moment of the tire pattern.

[0011] In some embodiments of the present application, the design parameters of the target tire are obtained, comprising: obtaining a three-dimensional model of the target tire, and obtaining material parameters for reflecting the mechanical properties of the target tire from the three-dimensional model under the condition of applying air pressure and radial load; obtaining a pattern model of the target tire, and obtaining pattern parameters of the tire pattern from the pattern model, wherein the pattern parameters include the angle of the cross groove for determining the inertia principal axis of the pattern block; determining the design parameters corresponding to the material parameters and the pattern parameters.

[0012] According to another aspect of the embodiments of the present application, a device for determining the residual aligning moment of the tire pattern is also provided, comprising: an obtaining module for obtaining the design parameters of the target tire, wherein the design parameters include the pattern parameters for reflecting the geometric characteristics of the tire pattern of the target tire; an executing module for determining the lateral force and the aligning moment of the tire pattern corresponding to the design parameters under a plurality of side slip angles; a fitting module for linearly fitting the lateral force and the aligning moment with the side slip angle to obtain a fitting result, wherein the fitting result is used to reflect the sensitivity of the lateral force and the aligning moment to the change of the side slip angle; a determining module for determining the target aligning moment according to the fitting result when the lateral force is zero, and taking the target aligning moment as the residual aligning moment of the tire pattern.

[0013] According to still another aspect of the embodiments of the present application, an electronic device is also provided, comprising: a memory and a processor, the memory is used to store program instructions; the processor is connected with the memory and is used to execute the above-mentioned method for determining the residual aligning moment of the tire pattern.

[0014] According to still another aspect of the embodiments of the present application, a non-volatile storage medium is also provided, comprising a stored computer program, wherein the device where the non-volatile storage medium is located executes the above-mentioned method for determining the residual aligning moment of the tire pattern by running the computer program.

[0015] According to still another aspect of the embodiments of the present application, a computer program product is also provided, comprising computer instructions, which are executed by the processor to implement the above-mentioned method for determining the residual aligning moment of the tire pattern.

[0016] In the embodiment of the present application, the theoretical analysis and data modeling are combined, the quantitative relationship between the target tire pattern parameters and the lateral force and the self-aligning moment is analyzed, the purpose of accurately predicting the contribution degree of the tire pattern to the residual self-aligning moment is achieved, the technical effects of quickly positioning the optimal pattern design parameter combination and improving the straight-line driving performance of the tire are achieved, and the technical problem that the simulation method is used to simulate the residual self-aligning moment of the tire in the related art, but the simulation cannot directly obtain the influence of the single pattern design factor on the residual self-aligning moment is solved. BRIEF DESCRIPTION OF DRAWINGS

[0017] The drawings described herein are used to provide further understanding of the present application, and form 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 improper limitations on the present application. In the drawings:

[0018] Figure 1 Fig. 1 is a hardware structure block diagram of a computer terminal of a tire pattern residual self-aligning moment determination method according to an embodiment of the present application;

[0019] Figure 2 Fig. 2 is a flowchart of a tire pattern residual self-aligning moment determination method according to an embodiment of the present application;

[0020] Figure 3 Fig. 3 is a schematic diagram of a pattern block inertia principal axis of a tire pattern residual self-aligning moment determination method according to an embodiment of the present application;

[0021] Figure 4 Fig. 4 is a schematic diagram of a tire pattern assembly of a tire pattern residual self-aligning moment determination method according to an embodiment of the present application;

[0022] Figure 5 Fig. 5 is a schematic diagram of a footprint surface pattern of a tire pattern residual self-aligning moment determination method according to an embodiment of the present application;

[0023] Figure 6 Fig. 6 is a structural schematic diagram of a tire pattern residual self-aligning moment determination device according to an embodiment of the present application. DETAILED DESCRIPTION

[0024] In order for those skilled in the art to better understand the present application, the technical solutions in the embodiments of the present application will be described clearly and completely below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, not all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor should be within the scope of protection of the present application.

[0025] It is to be understood that the terms "first", "second", and the like, used in the description and the claims of the present application as well as the above description of the drawings merely refer to categories and do not necessarily imply a specific order or chronology unless explicitly stated otherwise. It is to be understood that the use of the term "or" in the description and the claims of the present application has the same meaning as "and / or" unless explicitly stated otherwise. It is to be understood that the use of the term "comprising" or "having" in the description and the claims of the present application has the same meaning as "consisting of" unless explicitly stated otherwise. Furthermore, the terms "comprising" and "including" and any variations thereof are intended to cover a non-exclusive inclusion, such that processes, methods, systems, articles, or apparatuses that comprise, have, include steps or units that are not expressly listed are still within the scope of the present application.

[0026] In order to better understand the embodiments of the present application, the technical terms involved in the embodiments of the present application are explained as follows:

[0027] Residual Restoring Moment (PRAT): The restoring moment caused by the asymmetry of the tire pattern when the tire is in a small side slip angle state and the lateral force is zero, which is independent of the lateral dynamic effect of the vehicle and is only generated by the pattern design and structural characteristics of the tire itself. In the embodiments of the present application, PRAT is a key indicator for evaluating the influence of tire pattern design on the straight-line driving stability and handling performance of the vehicle. By establishing a mathematical model between the pattern parameters and PRAT, the residual restoring moment can be predicted and optimized at the tire design stage.

[0028] Lateral Force: The force generated along the vertical direction to the driving direction when the tire is subjected to a lateral force, mainly caused by the side slip angle. In the embodiments of the present application, the lateral force is one of the important indicators of the influence of tire pattern on the overall performance of the tire at different side slip angles, and its linear relationship with the side slip angle is used to understand how the tire pattern changes the lateral response characteristics of the tire.

[0029] Restoring Moment (RM): The moment generated by the tire to try to return the vehicle to a straight-line driving state when the vehicle is turning or side slipping, such as the tendency to return the steering wheel to the center position. In the embodiments of the present application, RM can be calculated through the asymmetric deformation and contact characteristics of the tire pattern, and the residual restoring moment (PRAT) can be represented as the RM value when the lateral force is zero, directly reflecting the influence of the tire pattern design on the straight-line driving stability and restoring characteristics of the vehicle.

[0030] Side Slip Angle (SSA): The angle deviation between the center of the tire contact patch and the centerline of the tire, generated when the vehicle is accelerating laterally or turning. In the embodiments of the present application, SSA can be used to measure the lateral force and aligning torque changes of the tire pattern. By linear fitting the lateral force and aligning torque data obtained within a small SSA range, the subtle influence of the pattern design on the lateral performance of the tire can be quantified.

[0031] Tire Trail: The horizontal distance between the leading edge of the tire contact patch and the center point of the vehicle's turning. It plays a key role in the calculation of the tire's lateral force and aligning torque. In the embodiments of the present application, accurate calculation of the trail helps to understand how the pattern design affects the tire's lateral force and aligning torque at a small side slip angle, and thus affects the vehicle's handling stability and straight-line performance.

[0032] The straight-line performance of the vehicle directly affects the safety and comfort of driving, and the residual aligning torque (PRAT) derived from the angle effect plays a crucial role. The PRAT value is influenced by both the internal cord angle of the tire and the pattern design of the tread. However, the related art faces significant challenges in evaluating the PRAT characteristics of the tire.

[0033] On the one hand, traditional experimental methods for directly measuring the PRAT of the tire not only consume a large amount of time, but also have high costs. The reason is that the experimental process needs to accurately control multiple variables, including the material properties of the tire, the cord angle, the pattern design, and the test environment conditions, to ensure the accuracy and reliability of the results. In addition, experiments often require the use of dedicated tire testing equipment, which has high maintenance and operation costs, limiting the frequency and range of experiments.

[0034] On the other hand, although simulation technology is widely used in related tire design to predict dynamic performance parameters such as PRAT, the simulation model is highly dependent on the accuracy of input parameters and the rationality of model assumptions. For the subtle relationship between pattern design factors and PRAT, simulation often fails to provide intuitive and accurate analysis, and simulation cannot directly analyze the direct impact of individual pattern design factors on PRAT, which makes it difficult for designers to accurately identify and optimize key pattern design elements that affect PRAT.

[0035] To solve the above technical problems, the embodiments of the present application provide corresponding solutions, which are described in detail below.

[0036] The determination method for the residual aligning torque of the tire pattern provided by the embodiments of the present application can be executed in a mobile terminal, a computer terminal, or a similar computing device. Figure 1A hardware structure block diagram of a computer terminal for implementing the determination method of the tire pattern residual righting moment is shown. As shown in Figure 1 The computer terminal 10 can include one or more processors (processors can include but not limited to microprocessor MCU or programmable logic device FPGA processing device, etc.), a memory 104 for storing data, and a transmission module 106 for communication function through wired and / or wireless network connection. In addition, it can also include a display, a keyboard, a cursor control device, an input / output interface (I / O interface), a universal serial bus (USB) port (which can be included as one of the ports of the I / O interface), a network interface, a BUS bus. Those skilled in the art can understand that Figure 1 The structure shown is only schematic, which does not limit the structure of the above-mentioned electronic device. For example, the computer terminal 10 can include more or less components than those shown in Figure 1 or have a different configuration than that shown in Figure 1 .

[0037] It should be noted that the one or more processors and / or other data processing circuits described above can be referred to herein as "data processing circuits" in general. The data processing circuit can be embodied in whole or in part as software, hardware, firmware or any other combination. In addition, the data processing circuit can be a single independent processing module, or all or part of any one of the other elements combined into the computer terminal 10. As referred to in the embodiments of the present application, the data processing circuit is a processor control (for example, the selection of the variable resistance terminal path connected with the interface).

[0038] The memory 104 can be used to store software programs and modules of application software, such as the program instructions / data storage device corresponding to the determination method of the tire pattern residual righting moment in the embodiments of the present application. The processor executes the software programs and modules stored in the memory 104 to perform various functional applications and data processing, that is, to implement the determination method of the tire pattern residual righting moment described above. The memory 104 can include a high-speed random access memory, and can also include a non-volatile memory, such as one or more magnetic storage devices, flash memory, or other non-volatile solid-state memory. In some examples, the memory 104 can further include a memory remotely disposed with respect to the processor, which can be connected to the computer terminal 10 through 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.

[0039] The transmission module 106 is configured to receive or send data via a network. The network can include, for example, a wireless network provided by a communication provider of the computer terminal 10. In one example, the transmission module 106 includes a network interface controller (NIC) that can connect to other network devices through a base station to communicate with the Internet. In one example, the transmission module 106 can be a radio frequency (RF) module that is configured to communicate with the Internet via a wireless connection.

[0040] The display can 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.

[0041] It is noted that in some alternative embodiments, the above-mentioned Figure 1 The computer terminal can include hardware elements (including circuitry), software elements (including computer code stored on a computer readable medium), or a combination of both hardware and software elements. It should be noted that in some embodiments, the computer terminal can be comprised of a plurality of computer terminals that are connected together via a network. Figure 1 is merely one example of a particular implementation and is intended to illustrate the types of components that can be present in the computer terminal.

[0042] In the above-described operating environment, the embodiments of the present application provide a method for determining a residual positive aligning torque of a tire pattern, and it is noted that the steps shown in the flowchart of the accompanying drawings can be executed in a computer system such as a set of computer executable instructions, and although a logical order is shown in the flowchart, in some cases, the steps shown or described herein can be executed in an order different from that shown herein.

[0043] Figure 2 is a flowchart of a method for determining a residual positive aligning torque of a tire pattern according to an embodiment of the present application, as shown in Figure 2 The method includes the following steps:

[0044] In step S202, design parameters of a target tire are obtained, wherein the design parameters include pattern parameters that reflect geometric characteristics of a tire pattern of the target tire.

[0045] In step S202, the design parameters include, but are not limited to, tire specifications, material distribution, cord angle, and tire pattern parameters, which are used to comprehensively reflect the mechanical properties and dynamic performance characteristics of the tire, wherein the pattern parameters refer to geometric characteristics such as depth, width, pitch length, arrangement, shape of pattern blocks, groove angle, and direction of the tire pattern, which directly affect the contact form and mechanical interaction between the tire and the ground, thereby determining the size and variation trend of the PRAT.

[0046] In some embodiments of the present application, the design parameters can be automatically extracted from the target tire pattern drawing drawn from the CAD software, involving reading the pitch pattern, pattern depth, transverse groove angle and other geometric characteristics of the tire pattern.

[0047] In order to realize accurate prediction of the residual cornering moment of the tire pattern, the design parameters of the target tire can be obtained by: obtaining a three-dimensional model of the target tire, and obtaining material parameters for reflecting the mechanical characteristics of the target tire from the three-dimensional model under the condition of applying air pressure and radial load; obtaining a pattern model of the target tire, and obtaining pattern parameters of the tire pattern from the pattern model, wherein the pattern parameters include a transverse groove angle for determining the inertia principal axis of the pattern block; determining the design parameters corresponding to the material parameters and the pattern parameters.

[0048] The three-dimensional model is a digital expression of the structure and shape of the target tire, which contains detailed geometric information of the internal structure, material distribution and external pattern of the tire. The material parameters cover the physical and mechanical properties of each component of the tire, such as elastic modulus, Poisson's ratio, density, etc.

[0049] In some embodiments of the present application, the three-dimensional model of the tire can be established by using finite element analysis software according to the tire material distribution map. In this process, the tire can be regarded as a multi-material composite structure, and the corresponding material parameters are set for each material partition. By applying air pressure and radial load, the working state of the tire under actual use conditions is simulated, and the length and width of the tire static load mark and the stress-strain distribution of the material are obtained. When establishing the three-dimensional model, considering that the material properties of the tire may change with temperature and aging in actual use, a material parameter dynamic adjustment mechanism can be adopted for real-time updating according to the thermal and aging characteristics of the material, ensuring the adaptability and prediction accuracy of the calculation model.

[0050] The pattern model is a digital representation specially designed for the tire pattern, which contains details such as pattern pitch, pattern block shape, groove angle and depth. The transverse groove angle is the inclination angle of the transverse groove with respect to the rotation direction of the tire, which directly determines the direction of the inertia principal axis of the pattern block. In some embodiments of the present application, the pattern model of the target tire can be created in the CAD software, and the key pattern parameters such as pattern pitch, pattern block shape and transverse groove angle can be extracted from the pattern model.

[0051] In the process of obtaining the design parameters of the tire, if there is a mismatch between the material parameters and the pattern parameters, it may result in a large deviation between the PRAT value predicted by the theoretical model and the actual situation, affecting the accuracy of tire design. To solve this problem, a unified tire design parameter database can be established, in which each set of tire design parameters (including material parameters and pattern parameters) is strictly verified to ensure their matching and consistency. In the parameter matching process, the cross-validation method is used to compare the PRAT prediction results of the same pattern model under different material parameter configurations, and the configuration with the smallest difference is selected as the best match. The selected material parameters and pattern parameters are input into the tire performance simulation model to simulate the PRAT value, which is compared with the experimental data to ensure the consistency of the theoretical calculation and the actual performance. If a difference is found, the parameters are adjusted again until the performance requirements are met, thereby ensuring the integrity of the tire design parameters and the reliability of the prediction results.

[0052] In step S204, the lateral force and the aligning torque of the tire pattern corresponding to the design parameters under a plurality of side slip angles are determined.

[0053] In the above step S204, the side slip angle refers to the angular deviation between the tire running direction and the force direction. In some embodiments of the present application, the plurality of side slip angles refer to a series of small angle ranges set for comprehensive evaluation of the influence of the tire pattern on the residual aligning torque (PRAT), for example, between -0.4° and 1°.

[0054] The lateral force is the lateral force generated by the tire when it contacts the ground under the action of the side slip angle, i.e., the force generated by the tire in the direction perpendicular to the tire running direction under the action of the side slip angle, which is a key indicator for measuring the stability of the tire when the vehicle turns or the road surface is uneven. The aligning torque generated by the tire when subjected to the lateral force is the tendency of the tire to attempt to restore to a straight running direction.

[0055] In some embodiments of the present application, a method combining theoretical calculation and numerical simulation can be used to analyze the lateral force and the aligning torque of the tire under different side slip angles by establishing a mechanical model of the tire pattern block. This process involves calculating the deformation and stress distribution of a single pattern block under the action of the side slip angle, and then deducing the contribution of each pattern block to the overall lateral force and aligning torque of the tire.

[0056] It should be noted that after obtaining the lateral force and aligning torque of the tire pattern under each cornering angle, parameter sensitivity analysis can also be performed, that is, the degree of influence of small changes in design parameters (such as pattern depth, cross groove angle, etc.) on the lateral force and aligning torque is studied, so as to identify which pattern design features have the most significant influence on PRAT, thereby giving priority attention in tire design optimization. Sensitivity analysis solves the problem of difficult direct identification of key design points under the influence of multiple factors, and provides accurate guidance for tire pattern design.

[0057] In order to more accurately evaluate the contribution of each pattern block to the overall lateral force and aligning torque, the longitudinal force and lateral force can be calculated in the coordinate system corresponding to the principal axis of inertia of the pattern block, and then converted to the coordinate system in the direction of travel of the tire. Specifically: obtaining the principal axis of inertia corresponding to the target pattern block in the tire pattern, wherein the target pattern block is any one of the plurality of pattern blocks of the tire pattern in the footprint of the target tire, and the inertia moment of the target pattern block is smallest when rotating around the principal axis of inertia; determining a first coordinate system corresponding to the principal axis of inertia, and determining a first longitudinal force and a first lateral force of the target pattern block in the first coordinate system; converting the first longitudinal force and the first lateral force into a second longitudinal force and a second lateral force in a second coordinate system, wherein the second coordinate system is a Cartesian coordinate system determined along the direction of travel of the target tire; determining the lateral force and the aligning torque of the tire pattern according to the second longitudinal force, the second lateral force and the corresponding cornering angle of all pattern blocks.

[0058] The principal axis of inertia is an axis around which the tire pattern block has the smallest inertia moment when rotating, and this characteristic determines the rotational stability of the pattern block under the action of the cornering force. The direction of the principal axis of inertia is closely related to the geometric shape and material distribution of the pattern block.

[0059] The first coordinate system is a coordinate system established with the principal axis of inertia as a reference, which is used to describe the force distribution of the target pattern block in a natural state (without the influence of the cornering force). The second coordinate system is a Cartesian coordinate system established along the direction of travel of the tire, which ensures that all calculation results are based on the same reference direction, facilitating the comparison of the lateral force and the aligning torque of the tire pattern under different cornering angles, thereby providing a unified standard for dynamic performance analysis of the tire.

[0060] In some embodiments of the present application, the principal axis of inertia of the target pattern block can be determined through inertia moment analysis in theoretical mechanics, for example, by first calculating the center of mass of the pattern block, then calculating the inertia moment of the pattern block around different axes, and finally selecting the axis with the smallest inertia moment as the principal axis of inertia. After calculating the first longitudinal force and the first lateral force of the target pattern block in the first coordinate system, these forces are converted to the second coordinate system using a coordinate transformation matrix to obtain the second longitudinal force and the second lateral force. This conversion ensures a direct correlation between the calculation results of the forces and the direction of travel of the tire, simplifying the subsequent calculation of the aligning torque.

[0061] Figure 3 is a schematic diagram of the inertia principal axis of a pattern block according to a method for determining the residual aligning torque of a tire pattern of an embodiment of the present application, as shown in Figure 3 The PRAT of a tire pattern (i.e., the tread pattern) mainly comes from the torque caused by the non-parallel or non-perpendicular of the inertia principal axis of each pattern block to the driving direction of the tire.

[0062] Suppose the Cartesian coordinate system is xoy, the force generated by a single tread pattern along this axis is F x and F y ; the inertia principal axis coordinate system is XOY, the force generated by a single tread pattern along this axis is F X and F Y , then the force of the pattern in the inertia principal axis coordinate system is calculated as:

[0063]

[0064] The angle between the positive direction of the inertia principal axis X and the positive direction of the Cartesian coordinate system x is θ, according to the rotation formula, the direction of the force is rotated to the Cartesian coordinate system, then the longitudinal force and the lateral force in the driving direction of the tire can be represented as

[0065]

[0066] In the above formula 1 and formula 2, F X and F x represent the longitudinal force in the inertia principal axis coordinate system (i.e., the first longitudinal force) and the longitudinal force in the Cartesian coordinate system (i.e., the second longitudinal force), respectively, F Y and F y represent the lateral force in the inertia principal axis coordinate system (i.e., the first lateral force) and the lateral force in the Cartesian coordinate system (i.e., the second lateral force), respectively, K X and K Y represent the stiffness coefficients along the corresponding coordinate axis transverse and longitudinal directions, reflecting the ability of the pattern block to resist deformation under external force, U X and U Y represent the displacement along the corresponding coordinate axis transverse and longitudinal directions, which is the deformation of the pattern block under force.

[0067] Once the second longitudinal force and the second lateral force of all pattern blocks are determined in the second coordinate system, the aligning torque formed by the longitudinal force and the lateral force of each pattern block when the tire is purely rolling forward can be determined.

[0068] The geometry of tire blocks is complex and varied, and different pattern designs can make the calculation of the principal axis of inertia complex, especially when the block size is small or irregular in shape, the accurate identification of the principal axis of inertia becomes a challenge. In order to solve this problem, deep learning and image analysis algorithms can be used to automatically identify and accurately calculate the geometric characteristics of the tire block, including the center of mass position and contour, so as to accurately determine the principal axis of inertia thereof; for the preliminary calculated principal axis of inertia, the geometric parameters of the block are adjusted in time by comparing with the simulation results of the overall performance of the tire, until the calculation results of the principal axis of inertia are consistent with the performance of the tire.

[0069] The aligning moment of the tire pattern is determined according to the corresponding second longitudinal force, second lateral force and corresponding side slip angle of all the blocks, specifically: obtaining a longitudinal deformation index of a target block, wherein the longitudinal deformation index is used to represent the compression or stretching deformation amount of the target block in the rolling direction of the tire; determining a trail of the target tire, wherein the trail is used to represent the vertical distance from the lateral force action point of the target tire to the center axis of rotation of the target tire; determining a moment length of the target block according to the longitudinal deformation index, the trail and the side slip angle, wherein the moment length is used to represent the vertical distance between the center of the target block and the center axis of rotation of the target tire; determining an aligning moment corresponding to the moment length.

[0070] The longitudinal deformation index represents the deformation degree of the tire block in the rolling direction of the tire, that is, the compression or stretching degree, which directly affects the pressure distribution and friction force of the block in contact with the ground, thereby affecting the lateral force and aligning moment of the tire. In some embodiments of the present application, the longitudinal deformation amount of each block on the contact surface of the tire is calculated by loading different side slip angles in the simulation conditions of the tire in the three-dimensional model, and then the longitudinal deformation index is obtained.

[0071] The trail is the vertical distance from the lateral force action point of the tire to the center axis of rotation of the tire, which is an important parameter for calculating the aligning moment of the tire. In the case of small side slip angle (such as-0.4° to 1°), the contact surface of the tire is almost completely in the viscous region, and the size of the trail determines the degree of influence of the lateral force on the aligning tendency of the tire.

[0072] The trail can be determined by: determining a third lateral force and a viscous aligning moment corresponding to a target area of the target tire, wherein the target area includes an area formed by the contact surface of the target tire and the road surface without slip; determining the ratio of the third lateral force to the viscous aligning moment as the trail.

[0073] Since the corresponding side slip angle of the residual aligning moment is very small, it is assumed that the entire stick zone in the tire footprint (referring to the state that the contact surface of the tire (i.e., the contact area between the tire tread pattern and the road surface) is in a state of adhesion rather than slip when the tire is in contact with the road surface) does not slip, and the overall tire lateral force and aligning moment corresponding to the stick zone are:

[0074]

[0075] In the above formula 3 and formula 4, is the third lateral force, is the stick aligning moment, C y is the tire lateral stiffness, b is the tire width, and l is the crown footprint length.

[0076] The ratio of the third lateral force to the stick aligning moment is determined as the drag distance, that is, the tire drag distance

[0077] The moment length is the vertical distance between the center of the pattern block and the rotation center axis of the tire, and the change of the moment length reflects the influence of the tire pattern design on the aligning moment. After determining the moment length, in some embodiments of the present application, the aligning moment can be calculated by the following formula:

[0078]

[0079] In the above formula 5, M z is the aligning moment, F xi , F yi is the longitudinal force and lateral force of the i th pattern block (N in total) in the footprint surface, which can be obtained according to formula 1 and formula 2, l xi , l yi = f(u x , t trail , a) is the moment length corresponding to the lateral force and longitudinal force of the i th pattern block in the footprint surface, f(x) is a function of the pattern longitudinal deformation u x , the tire side slip angle a, and the tire drag distance t trail , and the longitudinal deformation of the tire tread pattern can be determined by the tire load condition, the road surface friction and the stiffness.

[0080] In some embodiments of the present application, given the side slip angle a is -0.4° to 1°, the lateral force and aligning moment of the tire tread pattern at the corresponding side slip angle can be calculated according to the above formula 1 to formula 5.

[0081] In step S206, the lateral force and the aligning moment are linearly fitted with the side slip angle to obtain a fitting result, wherein the fitting result is used to reflect the sensitivity of the lateral force and the aligning moment to the change of the side slip angle.

[0082] In step S206, the least square linear regression can be used to find the best fitting line by minimizing the sum of squared residuals, or robust linear regression (e.g., least absolute deviation regression) or ensemble learning methods such as random forest can be used, which are not limited herein.

[0083] In some embodiments of the present application, the plurality of side slip angles can be linearly fitted with the corresponding lateral forces and aligning moments, respectively, to obtain first fitting results and second fitting results, wherein the first fitting results are used to reflect the sensitivity of the lateral force to the change of the side slip angle, and the second fitting results are used to reflect the sensitivity of the aligning moment to the change of the side slip angle.

[0084] For example, the lateral force F y and the aligning moment M z respectively, can be fitted with the side slip angle a by the following formulas:

[0085] F y = λ1·a + b1 (Formula 6)

[0086] M z = λ2·a + b2 (Formula 7)

[0087] In the above formulas 6 and 7, λ1 and λ2 represent the slope, reflecting the sensitivity of the lateral force and the aligning moment to the change of the side slip angle, and b1 and b2 represent the intercept, representing the baseline value of the lateral force and the aligning moment in the absence of the side slip angle. The best (λ1, λ2, b1, b2) value is found by the least square method, so that the deviation between the fitted line and the data points is minimized, thereby obtaining the linear fitting results (formula 6 corresponds to the first fitting result, and formula 7 corresponds to the second fitting result).

[0088] In step S208, the target aligning moment is determined according to the fitting results when the lateral force is zero, and the target aligning moment is taken as the residual aligning moment of the tire pattern.

[0089] In the above step S208, the case where the lateral force is zero means that the tire as a whole does not show a tendency to move laterally under the action of the lateral force, and in this case, the aligning moment of the tire is investigated, which can more purely evaluate the influence of the tire pattern design on the residual aligning moment without being disturbed by other factors.

[0090] The target aligning moment is the aligning moment caused by the tire pattern design when the lateral force is zero, which directly reflects the self-correcting ability of the tire when driving in a straight line.

[0091] In the case of zero lateral force, the target aligning torque is determined according to the fitting result, and the target aligning torque is taken as the residual aligning torque of the tire pattern. Specifically, in the case of zero lateral force, the corresponding target side slip angle in the first fitting result is determined, wherein the target side slip angle is used to simulate the state of the target tire maintaining straight driving relying on the tire pattern without any external lateral force intervention; the target side slip angle is brought into the second fitting result for calculation to obtain the target aligning torque, and the target aligning torque is taken as the residual aligning torque of the tire pattern.

[0092] The target side slip angle is the side slip angle corresponding to zero lateral force, which simulates the angle of the tire maintaining straight driving only relying on the tire pattern design without external lateral force intervention.

[0093] In the case of zero lateral force, the change of the side slip angle can be very small, which can weaken the prediction ability of the linear fitting model in this interval, resulting in inaccurate calculation results of the target side slip angle and the residual aligning torque. To this end, before linear fitting, ensure that enough and high-precision data points are collected in the interval of the side slip angle close to zero; in the interval close to zero, the linear model can not fully describe the complex relationship between force and torque, at this time, higher order polynomial regression or nonlinear model (such as neural network model) can be considered to improve the fitting accuracy; the prediction ability of different models in the interval of extremely small lateral force is evaluated by cross-validation, and the model is calibrated according to the actual test results to adjust the model parameters, so as to ensure that the model can also provide accurate lateral force and aligning torque prediction when the side slip angle is close to zero.

[0094] Through the above steps S202 to S208, by combining theoretical analysis and data modeling, the quantitative relationship between the target tire pattern parameters and the lateral force and the aligning torque is analyzed, the purpose of accurately predicting the contribution degree of the tire pattern to the residual aligning torque is achieved, thereby realizing the technical effects of quickly positioning the optimal pattern design parameter combination and improving the straight driving performance of the tire, and further solving the technical problem that the related art uses simulation method to simulate the residual aligning torque of the tire, but the simulation cannot directly obtain the influence of the single pattern design factor on the residual aligning torque.

[0095] In order to facilitate the understanding of the above process, some specific embodiments are explained below. In some embodiments of the present application, the technical route for calculating the pattern PRAT based on the pattern drawing paper drawn by the target software is as follows:

[0096] (1) Obtain the pattern model and basic information;

[0097] (2) Assemble the pattern according to the pattern arrangement information;

[0098] (3) automatically draw the print surface;

[0099] (4) extract the pattern information in the print surface to calculate the pattern PRAT;

[0100] (5) output the result.

[0101] In step (1), the pattern information includes: pattern pitch length, arrangement information, and pattern rubber used; in step (2), the whole tire is assembled automatically in the target software according to the arrangement information in step (1), as shown in Figure 4 ; in step (3), the print is automatically drawn in the target software according to the print information in step (1), as shown in Figure 5 ; and in step (4), the pattern PRAT in the print surface is calculated according to the theoretical calculation formula (i.e., the above formula 1 to formula 7) and the corresponding pattern information.

[0102] Figure 4 is a tire pattern assembly schematic diagram of a method for determining the residual righting moment of a tire pattern according to an embodiment of the present application, as shown in Figure 4 , which shows the assembly layout of the tire pattern, i.e., the arrangement of the pattern blocks on the tire circumference, including the shape, size, and relative position of each pattern block, presenting the designer's design concept of the tire pattern, including the repeating unit of the pattern, the shape of the pattern block, and the spatial configuration.

[0103] Figure 5 is a pattern in the print surface schematic diagram of a method for determining the residual righting moment of a tire pattern according to an embodiment of the present application, as shown in Figure 5 , which shows a detailed view of the pattern in the tire ground print area. The tire ground print refers to the area of the tire in contact with the ground under load, which reflects the pattern distribution and morphology when the tire contacts the ground, and provides an intuitive view of the tire pattern under actual working conditions (i.e., in the ground print area).

[0104] Take the specific tire specification 205 / 60R16 as an actual case, and calculate the pattern PRAT according to the above steps and compare it with the simulation result.

[0105] 1. Obtain the print information of the tire: the print information can be obtained by simulation or experiment. In this embodiment, a simulation model is established according to the material distribution map of the designed 205 / 60R16 tire. After uniform air pressure and radial load are applied, the specific data of the tire ground print are obtained as follows: print length 165 mm, print width 155 mm, and print length at 80% of the shoulder 141 mm.

[0106] 2. Arrange and assemble according to the pattern information and the model, as shown in Figure 4 ;

[0107] 3. Get the pattern in the footprint plane according to the simulated footprint information, see Figure 5 ;

[0108] 4. Calculate the pattern PRAT result according to the information extracted in the model.

[0109]

[0110] Since PRAT is essentially a moment of force, the moments of force in the same direction can be directly superimposed, and the PRAT result caused by the pattern can be indirectly calculated from the PRAT calculated by the whole tire and the PRAT calculated by the pure longitudinal groove tire. The PRAT simulation and theoretical results of the present specification and the pattern are as follows:

[0111] PRAT / (N mm) Simulation results 12.05 Theoretical results 12.78 Error 6.12％

[0112] The present application establishes a tire tread pattern PRAT analysis algorithm, which can directly establish the relationship between the tire tread pattern design factor and the PRAT performance from the perspective of theoretical analysis, predict the pattern PRAT performance at the design stage, and conduct targeted pattern design, reduce the pattern design cost, and improve the pattern design efficiency. Tire design engineers can quickly locate the optimal design parameter combination through multi-scheme design, which has important application value, and also provides a certain reference for the relationship between belt angle and PRAT performance. Compared with simulation, the PRAT prediction method provided by the present application does not need to rely on simulation calculation, nor does it need to repeatedly experiment and verify, saving time and economic costs.

[0113] Figure 6 is a structural diagram of a determination device for a residual righting moment of a tire pattern according to an embodiment of the present application, as shown in Figure 6 , the device comprises:

[0114] The acquisition module 602 is configured to acquire design parameters of a target tire, wherein the design parameters comprise pattern parameters for reflecting geometric characteristics of a tire pattern of the target tire.

[0115] The execution module 604 is configured to determine lateral forces and righting moments of the tire pattern corresponding to the design parameters at a plurality of side slip angles.

[0116] The fitting module 606 is configured to linearly fit the lateral forces and the righting moments with the side slip angles to obtain a fitting result, wherein the fitting result is used to reflect the sensitivity of the lateral forces and the righting moments to changes in the side slip angles.

[0117] The determination module 608 is configured to determine a target righting moment according to the fitting result when the lateral force is zero, and take the target righting moment as the residual righting moment of the tire pattern.

[0118] It should be noted that, Figure 6The tire pattern residual aligning moment determination device shown is used to execute Figure 2 The tire pattern residual aligning moment determination method shown, therefore Figure 2 The relevant explanations in the tire pattern residual aligning moment determination method in Figure 6 The tire pattern residual aligning moment determination device shown, which is not described here.

[0119] The electronic device includes a memory and a processor, wherein the memory is configured to store program instructions; the processor is connected with the memory and is configured to execute steps of the tire pattern residual aligning moment determination method in various embodiments of the present application.

[0120] For example, the processor executes the following functions by executing the program instructions stored in the memory: obtaining a design parameter of a target tire, wherein the design parameter includes a pattern parameter used to reflect a geometric feature of a tire pattern of the target tire; determining a lateral force and an aligning moment of the tire pattern corresponding to the design parameter under a plurality of side slip angles; linearly fitting the lateral force and the aligning moment with the side slip angles to obtain a fitting result, wherein the fitting result is used to reflect a sensitivity of the lateral force and the aligning moment to a change in the side slip angle; determining a target aligning moment according to the fitting result in a case where the lateral force is zero, and taking the target aligning moment as a residual aligning moment of the tire pattern.

[0121] The non-volatile storage medium includes a stored computer program, wherein a device in which the non-volatile storage medium is located executes steps of the tire pattern residual aligning moment determination method in various embodiments of the present application by running the computer program.

[0122] The computer program product includes computer instructions, which, when executed by a processor, implement steps of the tire pattern residual aligning moment determination method in various embodiments of the present application.

[0123] The computer program, when executed by a processor, implements steps of the tire pattern residual aligning moment determination method in various embodiments of the present application.

[0124] The above sequence numbers of the embodiments of the present application are only for description, and do not represent advantages or disadvantages of the embodiments.

[0125] In the above embodiments of the present application, the description of each embodiment has its own focus, and the parts not described in detail in a certain embodiment can be referred to the relevant description of other embodiments.

[0126] In several embodiments provided in the present application, it should be understood that the disclosed technology can be implemented by other ways. Among them, the above-described device embodiments are only schematic, for example, the division of the units can be a logical function division, and actual implementation can have another division manner, for example, a plurality of units or components can be combined or integrated into another system, or some features can be ignored or not executed. In addition, the coupling or direct coupling or communication connection between the displayed or discussed units can be indirect coupling or communication connection through some interfaces, units or modules, and can be electrical or other forms.

[0127] The units described as separate components can or can not be physically separate, and the components shown as units can or can not be physical units, i.e. can be located in one place or can be distributed to multiple units. Part or all of the units can be selected according to actual needs to achieve the purpose of the embodiment.

[0128] In addition, the functional units in each embodiment of the present application can be integrated in one processing unit, or each unit can be physically present separately, or two or more units can be integrated in one unit. The integrated unit can be realized in the form of hardware or in the form of a software functional unit.

[0129] The integrated unit, if realized in the form of a software functional unit and sold or used as an independent product, can be stored in a computer readable storage medium. Based on this understanding, the technical solutions of the present application essentially or the part that contributes to the prior art or the whole or part of the technical solutions can be embodied in the form of a software product. The computer software product is stored in a storage medium, including a plurality of instructions for causing a computer device (which can be a personal computer, a server or a network device, etc.) to execute all or part of the steps of the method described in each embodiment of the present application. The foregoing storage medium includes: U disk, read-only memory (ROM, Read-Only Memory), random access memory (RAM, Random Access Memory), mobile hard disk, magnetic disk or optical disk and various program codes that can be stored in the medium.

[0130] The above is only the preferred embodiment of the present application, and it should be pointed out that for ordinary skilled in the art, without departing from the principles of the present application, a number of improvements and refinements can be made, and these improvements and refinements should be considered as the protection scope of the present application.

Claims

1. A method of determining residual regenerative torque of a tire pattern, characterized in that, The method comprises: obtaining design parameters of a target tire, wherein the design parameters include pattern parameters reflecting geometric characteristics of a tire pattern of the target tire; determining lateral forces and aligning moments of the tire pattern corresponding to the design parameters at a plurality of side slip angles; linearly fitting the lateral forces and the aligning moments with the side slip angles to obtain a fitting result, wherein the fitting result reflects the sensitivity of the lateral forces and the aligning moments to the change of the side slip angles; determining a target aligning moment according to the fitting result when the lateral force is zero, and taking the target aligning moment as a residual aligning moment of the tire pattern.

2. The method of claim 1, wherein, The method comprises: obtaining an inertia principal axis corresponding to a target block of the tire pattern, wherein the target block is any one of a plurality of blocks of the tire pattern on a footprint surface of the target tire, and the target block has the smallest inertia moment when rotating around the inertia principal axis; determining a first coordinate system corresponding to the inertia principal axis, and determining a first longitudinal force and a first lateral force of the target block in the first coordinate system; converting the first longitudinal force and the first lateral force into a second longitudinal force and a second lateral force in a second coordinate system, wherein the second coordinate system is a Cartesian coordinate system determined along a running direction of the target tire; determining the lateral force and the aligning moment of the tire pattern according to the second longitudinal force, the second lateral force and the corresponding side slip angle of all blocks.

3. The method of claim 2, wherein, The method comprises: obtaining a longitudinal deformation index of the target block, wherein the longitudinal deformation index represents the compression or stretching deformation amount of the target block in the tire rolling direction; determining a trail of the target tire, wherein the trail represents the vertical distance from the lateral force action point of the target tire to the center axis of the target tire; determining a moment length of the target block according to the longitudinal deformation index, the trail and the side slip angle, wherein the moment length represents the vertical distance between the center of the target block and the center axis of the target tire; determining the aligning moment corresponding to the moment length.

4. The method of claim 3, wherein, The method comprises: determining a third lateral force and a viscous aligning moment corresponding to a target area of the target tire, wherein the target area includes an area formed when the contact surface of the target tire and the road surface does not slip; determining the trail as the ratio of the third lateral force to the viscous aligning moment.

5. The method of claim 1, wherein, The method comprises: linearly fitting the plurality of side slip angles with corresponding lateral forces and aligning moments respectively to obtain first fitting results and second fitting results, wherein the first fitting results are used to reflect sensitivity of the lateral forces to changes in the side slip angles, and the second fitting results are used to reflect sensitivity of the aligning moments to changes in the side slip angles.

6. The method of claim 5, wherein, In a case where the lateral force is zero, determining a target aligning moment according to the fitting results, and taking the target aligning moment as a residual aligning moment of the tire pattern, comprising: In a case where the lateral force is zero, determining a target side slip angle corresponding to the first fitting results, wherein the target side slip angle is used to simulate a state in which the target tire maintains straight driving by the tire pattern without any external lateral force intervention; linearly fitting the plurality of side slip angles with corresponding lateral forces and aligning moments respectively to obtain first fitting results and second fitting results, wherein the first fitting results are used to reflect sensitivity of the lateral forces to changes in the side slip angles, and the second fitting results are used to reflect sensitivity of the aligning moments to changes in the side slip angles.

7. The method of claim 1, wherein, obtaining design parameters of a target tire, comprising: obtaining a three-dimensional model of the target tire, and obtaining material parameters reflecting mechanical properties of the target tire from the three-dimensional model under the conditions of applied air pressure and radial load; obtaining a pattern model of the target tire, and obtaining pattern parameters of the tire pattern from the pattern model, wherein the pattern parameters include a cross groove angle used to determine an inertia principal axis of a pattern block; determining design parameters corresponding to the material parameters and the pattern parameters.

8. A device for determining the residual regenerative moment of a tire pattern, characterized in that it comprises: comprising: an obtaining module, configured to obtain design parameters of a target tire, wherein the design parameters include pattern parameters reflecting geometric characteristics of a tire pattern of the target tire; an executing module, configured to determine lateral forces and aligning moments of the tire pattern corresponding to the design parameters respectively under a plurality of side slip angles; a fitting module, configured to linearly fit the lateral forces and the aligning moments with the side slip angles to obtain fitting results, wherein the fitting results are used to reflect sensitivity of the lateral forces and the aligning moments to changes in the side slip angles; a determining module, configured to, in a case where the lateral force is zero, determine a target aligning moment according to the fitting results, and take the target aligning moment as a residual aligning moment of the tire pattern.

9. An electronic device, comprising: comprising: a memory and a processor, the memory is used to store program instructions; the processor is connected with the memory, and is used to execute a tire pattern residual aligning moment determination method in any one of claims 1 to 7.

10. A non-volatile storage medium, comprising: The non-volatile storage medium comprises a stored computer program, wherein the device where the non-volatile storage medium is located executes the tire pattern residual aligning moment determination method in any one of claims 1 to 7 by running the computer program.

11. A computer program product comprising computer instructions, characterized in that, The computer instructions are executed by the processor to implement the tire pattern residual aligning moment determination method in any one of claims 1 to 7.

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