A method, application and program product for automatically extracting tire numerical simulation contact patch information

Abstract

The present invention relates to the field of tire design technology, and more particularly to a method, application, and computer program product for automatically extracting tire numerical simulation contact patch information. A method for automatically extracting tire numerical simulation contact patch information comprises the following steps: 1) obtaining node coordinate information after deformation of the tire model; 2) obtaining unit composition information in the tire model; 3) obtaining contact pressure or pressure information of the node; 4) obtaining the coordinate extreme value node of the contact node; 5) obtaining the adjacent nodes of the coordinate extreme value point of the contact node; 6) interpolating the coordinate extreme value point of the contact node with the adjacent nodes to obtain the length and width of the contact patch; and 7) calculating the average degree of contact pressure. The above method can realize the automatic extraction of tire numerical simulation contact patch information, which is convenient for comparison with experimental test results and tire solution evaluation.

Description

Technical Field

[0001] The present invention relates to the technical field of tire design, and in particular to a method, application and computer program product for automatically extracting tire numerical simulation contact patch information. Background Art

[0002] Tires are the only part of a vehicle that comes into contact with the road. Many of the vehicle's performance capabilities, such as braking, traction, and steering, are achieved through the tiny contact patch between the tire and the road. Furthermore, a tire's rolling resistance, noise, and wear resistance are also related to its contact patch. Therefore, contact patch has always been the first test item for tire performance evaluation, and its importance is self-evident. With the development of computers and computational mechanics, numerical simulation technology has been successfully applied to tire performance analysis and has become increasingly mature. Currently, numerical simulations of tire performance are generally based on general commercial software systems, such as Abaqus, Ansys, and Marc. The post-processing capabilities of these commercial software programs can directly and conveniently obtain information such as the tire contact patch area and contact pressure distribution cloud map. However, this information is not comprehensive or intuitive enough for tire design engineers.

[0003] In particular, information such as the length and width of the contact patch is difficult to accurately extract. This is primarily due to the fact that numerical simulation results are nodal data, requiring interpolation along the contact patch's length and width. This means that the outermost node A, with a pressure value in the calculated results, is generally not a true edge. Node B, located adjacent to it and farther from the center of the contact patch, has a pressure value of 0, but it is also not a true edge. The true edge lies between these two nodes. If point A is used as an edge point, the extracted contact patch information is smaller, while if point B is used as an edge point, the extracted contact patch information is larger. Furthermore, because the tire numerical simulation model has a longer circumferential mesh size and a different mesh size across the tire width, depending on the engineer's meshing goals, manual selection can result in significant errors, leading to varying measurement results between different engineers. Furthermore, general commercial numerical simulation software for processing tire contact patch cloud images can only provide qualitative visual perception and cannot accurately provide quantitative parameter indicators. The lack of a unified standard hinders performance analysis and evaluation.

[0004] Therefore, it is necessary to invent a method for automatically extracting tire numerical simulation contact patch information to achieve fast, accurate and standardized extraction of tire contact patch information. Summary of the Invention

[0005] In order to solve the above technical problems, the purpose of the present invention is to provide a method for automatically extracting tire numerical simulation contact patch information, thereby achieving fast, accurate and standardized extraction of tire contact patch information.

[0006] In order to achieve the above-mentioned purpose, the present invention adopts the following technical solutions:

[0007] A method for automatically extracting tire numerical simulation contact patch information, the method comprising the following steps:

[0008] 1) Obtain node coordinate information after tire model deformation

[0009] Read the tire numerical simulation result file, the node coordinate information of the surface nodes in the tire model that may contact the road surface, including the node number N i , the node's x i ,y i and z i Coordinate value;

[0010] 2) Obtain unit composition information in the tire model

[0011] Mainly refers to the surface unit composition information that may come into contact with the road in the tire model, including the unit number E j , the node numbers of the four nodes that make up the surface, N j1 , N j2 , N j3 , N j4 ;

[0012] 3) Obtain the ground pressure or pressure information of the node

[0013] Read the numerical simulation calculation result file of the tire model to obtain the ground pressure information of the ground node, including the node number N k , and its corresponding ground pressure p k ;

[0014] 4) Get the coordinate extreme node of the ground node

[0015] The road surface plane is the xy plane, the y direction is the tire contact patch width direction, and the x direction is the tire contact patch length direction. The grounding node can be obtained through step 3), and then the x and y coordinates of the grounding are compared to obtain the two nodes with the largest and smallest x coordinates. Their node numbers are recorded as N and N respectively. xmax and N xmin , and the two nodes with the largest and smallest y coordinates, whose node numbers are denoted as N ymax and N ymin ;

[0016] 5) Get the adjacent nodes of the extreme value point of the coordinate of the ground node

[0017] Compare the node coordinates obtained in step 3) to find the value of N in step 4) xmax and N xmin The node is closest to the point in the x direction, and the absolute value of its x coordinate is greater than Nxmax and N xmin The absolute value of the x-coordinate of the node, whose number is N oxmax and N oxmin , similarly, find the same N in step 4) ymax and N ymin The point closest to the node in the y direction is numbered N oyma x and N oymin ;

[0018] 6) Interpolate the coordinate extreme point of the grounding node and the adjacent nodes to obtain the length and width of the grounding footprint

[0019] N oxmax and N xmax Nodes are linearly interpolated, and N oxmin and N xmin The nodes are linearly interpolated and the ground pressure value at the edge of the actual ground footprint is set to p edge , which is generally the resolution of the equipment used to test tire contact, p edge The value range of is 10kPa~50kPa, and the ground length L is calculated according to the following formula:

[0020]

[0021] The ground width W is calculated according to the following formula:

[0022]

[0023] 7) Calculate the average ground pressure

[0024] According to the node data obtained in step 3), the coefficient of variation of the ground pressure is used to characterize the uniform distribution of the ground pressure, taking into account the comparability between different schemes. p The calculation method is:

[0025]

[0026] Where u is the mean value of the ground pressure; the smaller the Cp value, the more uniform the ground pressure distribution.

[0027] Through the above method, the automatic extraction of tire numerical simulation contact footprint information can be achieved, which is convenient for comparison with experimental test results and tire solution evaluation.

[0028] Furthermore, the present invention also discloses the application of the method in tire simulation modeling.

[0029] 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.

[0030] 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.

[0031] 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. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Figure 1 This is the technical flow chart of this application;

[0033] Figure 2 A schematic diagram of the surfaces and coordinate axes in the tire model that may come into contact with the road surface;

[0034] Figure 3 The node numbers and coordinate information of the surface of the tire model that may come into contact with the road surface;

[0035] Figure 4 Information about the surface elements in the tire model that may come into contact with the road surface;

[0036] Figure 5 Node ground pressure (pressure) information, node number and ground pressure value;

[0037] Figure 6 Schematic diagram of the coordinate extreme node position of the obtained grounding node;

[0038] Figure 7 Obtain a schematic diagram of the positions of the adjacent nodes of the coordinate extreme point of the grounding node;

[0039] Figure 8 is the ground pressure distribution of two different tires and C p value. DETAILED DESCRIPTION

[0040] 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.

[0041] Take the Abaqus calculation file of 21550R15 tire as an example:

[0042] (1) Obtain the node coordinate information of the tire model after deformation. Read the tire numerical simulation result .dat file, and the coordinate information of the surface nodes in the tire model that may contact the road surface (such as Figure 2 ), including the node number N i , the node's x i ,yi and z i Coordinate values, such as Figure 3 .

[0043] (2) Obtaining the unit composition information in the tire model. This mainly refers to the surface unit composition information in the tire model that may come into contact with the road surface (such as Figure 2 ), including unit number E j , the node numbers of the four nodes that make up the surface, N j1 , N j2 , N j3 , N j4 ,like Figure 4 .

[0044] (3) Obtain the ground pressure (pressure) information of the node. Read the numerical simulation calculation result file .dat of the tire model to obtain the ground pressure information of the ground node, including the node number N k , and its corresponding ground pressure p k ,like Figure 5 .

[0045] (4) Obtain the coordinate extreme node of the ground contact node. The road surface plane is the xy plane, the y direction is the width direction of the tire contact patch, and the x direction is the length direction of the tire contact patch (e.g. Figure 2 ), the grounding node can be obtained through step (3), and then the x and y coordinates of the grounding are compared to obtain the two nodes with the largest and smallest x coordinates, whose node numbers are recorded as N xmax =500458 and N xmin =400458, and the two nodes with the largest and smallest y coordinates, whose node numbers are respectively denoted as N ymax =450767 and N ymin =450309, such as Figure 6 .

[0046] (5) Obtain the adjacent nodes of the coordinate extreme point of the grounding node. Compare the node coordinate values ​​obtained in step (3) and find the node with the N in step (4). xmax and N xmin The node is closest to the point in the x direction, and the absolute value of its x coordinate is greater than N xmax and N xmin The absolute value of the x-coordinate of the node, whose number is N oxmax =510458 and N oxmin =390458, similarly, find the same as (4)

[0047] Chinese N ymax and N ymin The point closest to the node in the y direction is numbered N oymax =450766 and N oymin=450308, such as Figure 7 .

[0048] (6) Interpolate the coordinate extreme point of the grounding node and the adjacent nodes to obtain the length and width of the grounding footprint. oxmax and N xmax Nodes are linearly interpolated, and N oxmin and N xmin The nodes are linearly interpolated and the ground pressure value at the edge of the actual ground footprint is set to p edge =50kpa=0.05Mpa. The ground length L and width W are calculated according to the following formula:

[0049]

[0050]

[0051] x Nxmax =61.724

[0052] x Nxmin =-61.722

[0053] x oNxmax =72.108

[0054] x oNxmin =-72.106

[0055] y Nymax =58.581

[0056] y Nymi =-58.402

[0057] y oNymax =64.671

[0058] y oNymin =-64.492

[0059] p Nxma =0.0571Mpa

[0060] p Nxmin =0.0571Mpa

[0061] p Nymax =0.1047Mpa

[0062] p Nymin =0.1124Mpa

[0063] L=126.028mm

[0064] W=123.546mm

[0065] (7) Calculate the average degree of ground pressure. In order to quantify and index the ground pressure information, the uniform distribution of ground pressure is an important indicator that tire design engineers pay attention to. The uniform distribution of ground pressure is strongly correlated with tire wear, rolling resistance and braking performance. According to the node data obtained in step (3), the coefficient of variation of ground pressure is used to characterize the uniform distribution of ground pressure, taking into account the comparability between different schemes, and the coefficient of variation of ground pressure C is used to characterize the uniform distribution of ground pressure. p The calculation method is:

[0066]

[0067] The number of grounding nodes n = 297, where u is the average grounding pressure of 0.46177 MPa, and the calculated C p =0.55296.

[0068] Through the above method, the automatic extraction of tire numerical simulation contact patch information can be achieved, which is convenient for comparison with experimental test results and tire solution evaluation. The contact length and width values ​​can be accurately obtained using this patented method, and the error compared with the experimental test results is less than 1mm. However, if the color area is assigned according to the Abaqus cloud map, the contact patch length and width are 144.2mm and 129mm respectively, which is nearly 20mm different from the maximum error of the experimental results. It is also very convenient to use this patented method to compare the uniformity of the contact pressure distribution, such as Figure 8 The two contact prints shown belong to two different tires. It is difficult to judge the uniformity of the contact pressure between the two tires from the intuitive cloud map. p The values ​​can be compared intuitively, the C of the right tire contact patch p Smaller values ​​indicate more uniformity.

[0069] The foregoing are merely preferred embodiments of the present invention. These embodiments are all different implementations based on the overall concept of the present invention. The scope of protection of the present invention is not limited thereto. Any changes or substitutions that can be easily conceived by a person skilled in the art within the technical scope disclosed in the present invention should be included within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be based on the scope of protection of the claims.

Claims

1. A method for automatically extracting tire numerical simulation contact patch information, characterized in that: The method comprises the following steps: 1) Obtain node coordinate information after tire model deformation Read the tire numerical simulation result file, the node coordinate information of the surface nodes in the tire model that may contact the road surface, including the node number N i , the node x i , y i and z i Coordinate value; 2) Obtaining unit composition information in the tire model The composition information of the surface elements in contact with the road in the tire model, including the element number E j , the node numbers of the 4 nodes that make up the surface, N j1 , N j2 , N j3 , N j4 ; 3) Obtain the ground pressure or pressure information of the node Read the numerical simulation calculation result file of the tire model to obtain the ground pressure information of the ground node, including the node number N k , and its corresponding ground pressure p k ; 4) Get the coordinate extreme node of the ground node The road surface plane xy flat, y The direction is the width of the tire contact patch. x The direction is the length direction of the tire contact patch. The grounding node can be obtained through step 3) and then compared with the grounding node. x and y Coordinates, get x The two nodes with the largest and smallest coordinates are numbered as N xmax and N xmin ,as well as y The two nodes with the largest and smallest coordinates are numbered as N ymax and N ymin ; 5) Get the adjacent nodes of the extreme coordinate point of the ground node Compare the node coordinate values ​​obtained in step 3) to find the value that matches the node coordinates obtained in step 4). N xmax and N xmin The node is closest to the point in the x direction, and the absolute value of its x coordinate is greater than N xmax and N xmin The absolute value of the x-coordinate of the node, which is numbered as N oxmax and N oxmin , similarly, find the same N ymax and N ymin The point closest to the node in the y direction is numbered N oymax and N oymin ; 6) Interpolate the coordinate extreme points of the grounding node and the adjacent nodes to obtain the length and width of the grounding footprint right N oxmax and N xmax Nodes are linearly interpolated. N oxmin and N xmin The nodes are linearly interpolated and the ground pressure value at the edge of the actual ground footprint is set to p edge , the resolution of the equipment used to test tire contact p edge The value range is 10kPa~50kPa, and the grounding length L Calculated according to the following formula: Ground width W Calculate according to the following formula: 7) Calculate the average ground pressure According to the node data obtained in step 3), the coefficient of variation of the ground pressure is used to characterize the uniform distribution of the ground pressure, taking into account the comparability between different schemes. C p The calculation method is: Where u is the mean value of the ground pressure; the smaller the Cp value, the more uniform the ground pressure distribution.

2. Application of the method according to claim 1 in tire simulation modeling.

3. 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 of claim 1.

4. 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 claim 1 is implemented.

5. 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 claim 1 is implemented.

Images