Method, application and program product for identifying and visualizing slip and adhesion zones of tire contact patch

Abstract

The present invention relates to the field of tire simulation design technology, and more particularly to a method, application, and program product for identifying and visualizing the slip and adhesion zones of a tire's contact patch. This method processes numerical simulation data to determine the slip state of tire nodes within the contact patch and uses a program to visualize this state, providing technical support for tire design engineers.

Description

Technical Field

[0001] The present invention relates to the technical field of tire simulation design, and in particular to a method, application and program product for identifying and visualizing a slip zone and an adhesion zone of a tire contact patch. Background Art

[0002] One of the primary functions of a tire is to enable vehicle steering. When a vehicle turns, the tire deforms sideways, and the tread inevitably slips against the road surface. This slip is closely related to tire wear and lateral force loss, making it crucial for understanding and modeling tire dynamics. Identifying a tire's slip and adhesion zones allows for assessing tire wear and sideways characteristics, further providing a basis for tire structural design.

[0003] However, currently, the only way to identify the slip and adhesion zones between tires and the road surface is through experimental observation. This involves excavating a hole of a defined area in the center of the road surface, covering the hole with a high-strength glass plate, and placing a high-speed camera beneath the plate. As the tire rolls over the plate, the camera captures an image of the contact patch, which is then identified through image processing. This experimental method has drawbacks such as long processing times and high costs. Furthermore, adjustments to the tire structure require remanufacturing and retesting, which is labor-intensive and resource-intensive. Finite element method numerical simulation is a promising approach to this problem, but general-purpose simulation software cannot directly obtain the target data, let alone visualize it. Summary of the Invention

[0004] To address the aforementioned technical issues, the present invention provides a method for identifying and visualizing the slip and adhesion zones of a tire's contact patch. This method processes numerical simulation calculation results to determine the slip state of tire nodes within the contact patch, and uses a program to visualize the state, providing technical support for tire design engineers.

[0005] In order to achieve the above-mentioned purpose, the present invention adopts the following technical solutions:

[0006] A method for identifying a slip zone and an adhesion zone of a tire contact patch, the method comprising the following steps:

[0007] The first step is to extract the tire numerical simulation results

[0008] By compiling a program, the tangential force τ1i in the 1st direction and the tangential force τ2i in the 2nd direction of the tire tread at each node in the tire-road contact surface and the vertical pressure value pi are extracted, where i is the node number;

[0009] The second step is to determine the node slip state

[0010] Determine the node slip state according to the following formula and assign the node a slip state variable h i :

[0011]

[0012] τ i =p i ×u i , node slip h i =1

[0013] τ i <p i ×u i , node adhesion h i =2

[0014] Other untouched nodes, h i =0;

[0015] where u i is the friction coefficient between the material of the node and the road surface.

[0016] Preferably, the first step is extracted by programming in Python language.

[0017] Furthermore, the present invention provides a method for visualizing the slip zone and adhesion zone of a tire contact patch, the method comprising the above method and the following steps:

[0018] The third step is to display the node slip state variables

[0019] The coordinates of the contact nodes between the tire tread and the road surface are extracted. A relationship is formed between the nodes and elements of the contact surface, with element numbers: node 1, node 2, node 3, and node 4. The four nodes are connected by straight line segments, i.e., node 1-node 2-node 3-node 4-node 1. A grid is drawn using a graphics display program, and variable values ​​are set at the nodes. Based on the results of the second step, if the node slips, the node value is assigned to 1; if the node is adhered, the node value is assigned to 0.2; and if the node does not contact the road surface, the node value is assigned to 0. The program is used to perform two-dimensional interpolation within the contact surface to display a visual graph of the node slip state variable hi within the contact surface.

[0020] Preferably, in step three, a program is compiled using Python PyVista to perform two-dimensional interpolation within the contact surface and display a visual graph of the node slip state variables hi within the contact surface.

[0021] Furthermore, the present invention provides an application of the method in tire simulation design.

[0022] Furthermore, the present invention also discloses a computer device, comprising a memory, a processor, and a computer program stored in the memory, wherein the processor executes the computer program to implement the method.

[0023] Furthermore, the present invention also discloses a computer-readable storage medium having a computer program or instruction stored thereon, which implements the method when the computer program or instruction is executed by a processor.

[0024] Furthermore, the present invention also discloses a computer program product, comprising a computer program or instructions, which implement the method when executed by a processor.

[0025] The present invention adopts the above-mentioned technical solution. The method obtains the slip state of the tire nodes in the contact patch by processing the numerical simulation calculation result data, and uses a program to realize visual display, providing technical support for tire design engineers. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 This is the contact surface diagram between the tread of the 21550R15 tire and the road surface;

[0027] Figure 2 The contact surface between the tread and the road surface of the 21550R15 tire after deformation;

[0028] Figure 3 This is a schematic diagram of the contact points between the 21550R15 tire and the road surface;

[0029] Figure 4 The slip zone and adhesion zone of a 21550R15 tire with a 2-degree lateral deviation.

[0030] Figure 5 The slip zone and adhesion zone of the 21550R15 tire during straight-line braking;

[0031] Figure 6 This is the adhesion area when the 21550R15 tire is statically grounded, and there is no slip area. DETAILED DESCRIPTION

[0032] The present invention will be further described in detail below with reference to the accompanying drawings: This embodiment is implemented on the premise of the technical solution of the present invention, and a detailed implementation method is given, but the protection scope of the present invention is not limited to the following embodiments.

[0033] The present invention takes 21550R15 tire as an example.

[0034] The first step is to extract the tire numerical simulation results. The Python language is used to compile a program to extract the tire and road contact surface (such as Figure 1 and Figure 2 As shown) each node of the tire tread (as shown) Figure 3 ) 1 direction tangential force τ 1i and 2-direction tangential force τ 2i , vertical pressure value p i , where i is the node number. Some results are shown in Table 1.

[0035] Table 1 Normal force and tangential force values ​​at the contact point between the 21550R15 tire and the road

[0036] Unit number i <![CDATA[τ1]]> <![CDATA[τ2]]> p 750 5.4898E-02 4.5785E-02 3.032 752 0.1240 4.9874E-02 4.333 754 0.1824 4.9292E-02 5.051 756 0.1751 4.6418E-02 4.465 758 5.4197E-02 4.4839E-02 3.624 760 -9.1036E-02 4.4821E-02 2.933 762 -8.9643E-02 4.6206E-02 2.248 764 -5.6370E-02 4.3183E-02 1.5 766 -2.3701E-02 2.9278E-02 0.858 768 -3.1184E-03 1.6103E-02 0.4295 770 -3.9117E-04 1.8801E-03 5.55E-02 776 -5.8788E-04 1.5808E-03 5.59E-02 777 -6.4134E-03 1.3956E-02 0.4583 778 -1.2581E-02 1.9646E-02 0.6719 782 -1.9457E-02 2.2122E-02 0.842 783 -2.4026E-02 2.1537E-02 0.9414 784 -2.8260E-02 2.0392E-02 1.067 790 -2.8078E-02 1.0872E-02 1.035 791 -1.9268E-03 -1.9058E-03 9.23E-02

[0037] The second step is to determine the node slip state. Determine the node slip state according to the following formula and assign the node a slip state variable h i :

[0038]

[0039] τ ic =p i ×u i

[0040] τ i =τ ic Node slip Node adhesion h i =0.2

[0041] Other untouched nodes h i =0

[0042] where u i is the friction coefficient between the material of the node and the road surface.

[0043] Taking node 750 as an example, the friction coefficient is 0.5.

[0044]

[0045] τ 750c =3.032*0.5=1.5016

[0046] τ 750 <τ 750c

[0047] Therefore, the node numbered 750 is in a sticky state and is assigned a value of h. 750 =0.2.

[0048] Taking node 1719 as an example, τ1=1.5461E-03, τ2=-6.2217E-04, p=3.3333E-02, and the friction coefficient is 0.5.

[0049]

[0050] τ 1719c =(3.3333E-02)*0.5=0.00166659

[0051] τ 1719 =τ 1719c

[0052] Therefore, the node numbered 1719 is in a sliding state and is assigned a value of h. 1719 =1.

[0053] The calculation results of some other nodes are shown in Table 2.

[0054] Table 2 Slip state variable values ​​of some nodes on the tread of 21550R15 tire

[0055]

[0056]

[0057] The third step is to display the node slip state variables. The coordinates of the contact nodes between the tire tread and the road are extracted as shown in Table 3. The relationship between the nodes and elements of the contact surface is shown in Table 4, i.e., (element number: Node 1, Node 2, Node 3, Node 4). The four nodes are connected by straight lines: Node 1 - Node 2 - Node 3 - Node 4 - Node 1.

[0058] Table 3 Coordinate values ​​of some nodes on the tread of 21550R15 tire

[0059] Node number X coordinate Y coordinate Z coordinate 200829 -56.530428 46.801977 -300.27102 200828 -56.533074 49.030297 -300.19498 200827 -56.536916 51.264021 -300.11028 200826 -56.54064 53.505075 -300.01545 200825 -56.542074 55.758262 -299.90674 200824 -56.537549 58.029318 -299.78045 200823 -56.506847 60.325424 -299.60402 200806 -56.420927 62.752243 -299.2669 200805 -56.274236 65.140076 -298.81234 200802 -56.122422 66.990137 -298.40602 200801 -55.950148 68.839188 -297.96628 200796 -55.795688 70.481188 -297.54341 200793 -55.620437 72.423997 -296.9844 200792 -55.450366 74.367409 -296.34552 200787 -55.27415 76.321037 -295.60778 200779 -55.024724 78.937037 -294.51169 200778 -54.749427 81.513721 -293.25128 200777 -54.446899 84.009127 -291.83252 200776 -54.11105 86.41993 -290.2316

[0060] Table 4 Relationship between elements and nodes of the contact surface between the tread and the road of the 21550R15 tire

[0061]

[0062]

[0063] A grid was drawn using a graphics display program, and variable values ​​were set at the nodes. Based on the results of the second step, if the node slipped, the node value was assigned to 1; if the node was sticking, the node value was assigned to 0.2; if the node was not in contact with the road surface, the node value was assigned to 0. A program was compiled using Python PyVista to perform two-dimensional interpolation within the contact surface and display the node slip state variable h within the contact surface. i Visual graphics, such as Figure 4-Figure 6 shown.

[0064] According to the above method, the adhesion area and slip area when the tire contacts the road surface can be obtained and visualized. Figure 6 The contact state at the static tire load shows that no nodes slip, which is consistent with general experience, and Figure 4 and Figure 5 It is also consistent with the literature test and theoretical results, proving the validity of the patent of this invention.

[0065] The above is a description of the embodiments of the present invention. The above description of the disclosed embodiments will enable professionals in the field to implement or use the present invention. Various modifications to these embodiments will be apparent to professionals in the field. The general principles defined herein can be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention will not be limited to the embodiments shown herein, but should conform to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A method for visualizing the slip zone and adhesion zone of a tire contact patch, characterized in that: The method comprises the following steps: The first step is to extract the tire numerical simulation results By programming the system, the tangential force τ of each node on the tire tread in the contact area between the tire and the road is extracted. 1i and 2-direction tangential force τ 2i , vertical pressure value p i , where i is the node number; The second step is to determine the node slip state Determine the node slip state according to the following formula and assign the node a slip state variable h i : τ i = p i × u i , node slip h i =1 τ i < p i × u i , node adhesion h i =2 Other untouched nodes, h i =0; in u i is the friction coefficient between the material to which the node belongs and the road surface; Extract the coordinates of the contact nodes between the tire tread and the road surface. Form a relationship between the nodes and elements of the contact surface, number the elements: node 1, node 2, node 3, and node 4. Connect the four nodes with straight lines, i.e., node 1-node 2-node 3-node 4-node 1. Use a graphics display program to draw a grid and set variable values ​​at the nodes. Based on the results of the second step, if the node slips, the node value is assigned to 1; if the node is adhered, the node value is assigned to 0.2; if the node does not contact the road surface, the value is assigned to 0. Use the program to perform two-dimensional interpolation within the contact surface to display the node slip state variable h within the contact surface. i Visual graphics of .

2. The method for visualizing the slip zone and adhesion zone of a tire contact patch according to claim 1, characterized in that: The first step is to extract the data by programming in Python.

3. The method for visualizing the slip zone and adhesion zone of a tire contact patch according to claim 1, wherein: Step 3: Use Python PyVista to write a program to perform two-dimensional interpolation within the contact surface and display the node slip state variables within the contact surface. h i Visual graphics of .

4. Application of the method according to any one of claims 1 to 3 in tire simulation design.

5. A computer device comprising a memory, a processor, and a computer program stored in the memory, characterized in that: The processor executes the computer program to implement the method according to any one of claims 1 to 3.

6. A computer-readable storage medium having a computer program or instruction stored thereon, characterized in that: When the computer program or instruction is executed by a processor, the method according to any one of claims 1 to 3 is implemented.

7. A computer program product comprising a computer program or instructions, characterized in that When the computer program or instruction is executed by a processor, the method according to any one of claims 1 to 3 is implemented.

Images