A full-process joint simulation method and system for parameterized self-piercing riveting forming process

Abstract

The present invention discloses a full-process joint simulation method and system for a parameterized self-piercing rivet forming process, which builds a self-piercing rivet forming process simulation model, parameterizes the coordinates of mobile nodes in the self-piercing rivet forming process simulation model, builds a parameterized simulation model, and characterizes the changes in process parameters of the self-piercing rivet forming process simulation model through changes in the coordinates of mobile nodes; meshes the parameterized simulation model of the self-piercing rivet forming process, and solves and calculates the mesh-reconstructed parameterized simulation model of the self-piercing rivet forming process based on a batch script to obtain the node coordinate information of each component of the forming process; based on the node coordinate information of each component of the forming process, the cross-sectional characteristic mass size of the self-piercing rivet forming process simulation model is obtained. The present invention shortens the time for building a self-piercing rivet forming process simulation model under different process parameters and improves the efficiency of extracting simulation results.

Description

Technical Field

[0001] The present invention belongs to the technical field of metal material connection performance analysis, and in particular relates to a full-process joint simulation method and system for a parameterized self-piercing riveting forming process. Background Art

[0002] As a cold connection technology, the self-piercing riveting process can effectively solve the connection of the same or different materials and is widely used in multi-material hybrid vehicles. The quality of the self-piercing riveting forming process is directly related to the connection strength and connection reliability of the rivet point. The quality of the self-piercing riveting forming process is usually evaluated by measuring the profile characteristic quality dimensions (i.e., interlocking value, rivet head height, bottom thickness, etc.). There are many parameters that affect the quality of the self-piercing riveting forming process. In the actual production process, it is usually necessary to determine the reasonable self-piercing riveting process parameters through "multiple rounds of trial riveting", which leads to long cycles and high production costs.

[0003] As an efficient and visual analysis method, numerical simulation technology can intuitively observe the self-piercing riveting process and measure the quality dimensions of the section characteristics after forming. However, in order to determine the reasonable riveting process parameters (i.e., mold and rivet dimensions, etc.), the traditional analysis process requires manual modification of parameters, and then manual extraction of the section characteristic dimensions of the simulation model after numerical simulation. This manual processing method is still a time-consuming process, especially for data modification and result extraction of hundreds or thousands of simulation samples. Summary of the invention

[0004] In view of the shortcomings in the prior art, the present invention provides a full-process joint simulation method and system for a parameterized self-piercing rivet forming process, which can realize the construction of a parameterized self-piercing rivet forming process simulation model and the automatic measurement of the cross-sectional feature quality dimensions of the forming simulation model.

[0005] The present invention achieves the above technical objectives through the following technical means.

[0006] A full-process joint simulation method for parameterized self-piercing riveting forming process:

[0007] Build a simulation model of the self-piercing riveting process;

[0008] Parameterizing the coordinates of the moving nodes in the self-piercing rivet forming process simulation model, building a parameterized simulation model of the self-piercing rivet forming process, and characterizing the changes in the process parameters of the self-piercing rivet forming process simulation model through the changes in the coordinates of the moving nodes;

[0009] Reconstructing the mesh of the parametric simulation model of the self-piercing riveting forming process;

[0010] Based on the batch script, the parametric simulation model of the self-piercing riveting forming process after the computational grid reconstruction is solved to obtain the node coordinate information of each component in the forming process;

[0011] Based on the node coordinate information of each component in the forming process, the cross-sectional characteristic mass size of the parametric simulation model of the self-piercing riveting forming process is obtained.

[0012] Furthermore, the self-piercing riveting forming process simulation model includes the following components: a punch, a blank holder, a rivet, an upper plate, a lower plate and a die.

[0013] Furthermore, the process parameters of the self-piercing riveting forming process simulation model include: rivet size, mold size, upper plate thickness and lower plate thickness, the rivet size includes rivet length, rivet tip forward tilt angle, rivet tip backward tilt angle, and the mold size includes mold depth and mold inner diameter.

[0014] Furthermore, the coordinates of the moving nodes in the self-piercing riveting forming process simulation model are parameterized as follows:

[0015] Define the fixed nodes and mobile nodes of each component of the self-piercing riveting forming process simulation model and number them; the mobile nodes include key mobile nodes and impact area mobile nodes;

[0016] Extract all node information of each component in the self-piercing riveting forming process simulation model and group them according to the components;

[0017] The coordinate values ​​of the moving nodes in each component are defined as variables, and the process parameters of the self-piercing rivet forming process simulation model are changed by changing the coordinate values ​​of the moving nodes of each component, so as to obtain a parameterized simulation model of the self-piercing rivet forming process.

[0018] Furthermore, the fixed nodes and mobile nodes of each component include rivet fixed nodes and mobile nodes, upper plate fixed nodes and mobile nodes, lower plate fixed nodes and mobile nodes, and mold fixed nodes and mobile nodes; and:

[0019] The rivet fixed nodes are defined as M1 and M5, the key mobile nodes are defined as M2, M3 and M4, and the influence zone mobile nodes are defined as influence1, influence2, influence3, influence4 and influence5;

[0020] The upper plate fixed node is defined as M6, the key mobile node is defined as M7, and the influence zone mobile node is defined as influence6;

[0021] The fixed node of the lower plate is defined as M8, the key mobile node is defined as M9, and the mobile node of the influence area is defined as influence7;

[0022] The mold fixed node is defined as M10, the key mobile node is defined as M11, and the influence area mobile node is defined as influence8. Furthermore, all node information of each component in the model is extracted and grouped according to the components, specifically:

[0023] (1) Define the local coordinate system of the self-piercing riveting process simulation model, with the intersection of the upper surface of the rivet head and its symmetry center as the origin of the local coordinate system, the direction opposite to the movement of the punch as the positive direction of the Y axis, and the rivet thickness direction as the positive direction of the X axis;

[0024] (2) Extract all nodes of each component in the model and group them by component

[0025] For the rivet fixed node M1, traverse all the node coordinates of the rivet component and take the node with the smallest Y coordinate value as M1; for the key mobile node, define all the nodes of the rivet outer diameter as set A, and take the node with the smallest Y value in set A as the key mobile node M2; define all the nodes of the rivet inner diameter as set B, and take the node with the smallest Y value in set B as the key mobile node M3;

[0026] For the rivet length key mobile node M4, select the node whose Y coordinate value is greater than the largest node Y value in set A as M4; for the rivet fixed node M5, select the node whose Y coordinate value is less than or equal to the key mobile node M3 as the rivet fixed node M5;

[0027] For the mobile node influence1 in the influence area, traverse all nodes of the rivet component, select nodes whose Y coordinate values ​​are less than the key moving point M2 and define them as set C, and select nodes in set C whose X coordinate values ​​and Y coordinate values ​​are less than the key moving point M2 and the difference is less than the length of the grid unit as node 1; based on the same screening method, use node 1 to find the next node whose X coordinate value and Y coordinate value are less than node 1, and the difference between the X and Y coordinates of node 1 and node 1 is less than the length of the grid unit, as node 2, and iterate in sequence until all mobile nodes in the influence area of ​​influence1 are found;

[0028] For the mobile node influence2 in the influence area, the nodes whose Y coordinate value is less than the key mobile node M3 are filtered and defined as set D. In set D, the nodes whose X coordinate value and Y coordinate value are less than the key mobile node M3 and the difference is less than the length of the grid unit are filtered out in sequence until all the points of the mobile node influence2 in the influence area are found; the mobile node influence3 in the influence area is all the nodes in set A after removing M2; the mobile node influence4 in the influence area is all the nodes in set B after removing M3; the mobile node influence5 in the influence area is all the nodes whose Y coordinate value is greater than the rivet key mobile node M3 and less than the maximum Y coordinate value of the node in set A;

[0029] For the upper plate fixed node M6, traverse all the node coordinates of the upper plate component, and select the node with the smallest Y coordinate value as M6; for the key mobile node, traverse all the nodes of the upper plate component, and select the node with the largest Y coordinate value of the upper plate component and all the nodes of the rivet, punch, and blank holder as the key mobile point M7; the influence area mobile node influence6 is all the nodes of the upper plate component except M5 and M6;

[0030] For the fixed node M8 of the lower plate, all the node coordinates of the lower plate components are traversed, and the node with the smallest Y coordinate value is selected as the fixed node M8; for the key mobile node, all the nodes of the lower plate components are traversed, and the node with the largest Y coordinate value of the lower plate components, as well as the rivet, punch, blank holder and all the nodes of the upper plate are selected as the key mobile node M9; the mobile node influence7 in the influence area is all the nodes of the lower plate components except M8 and M9;

[0031] For the mold fixed node M10, traverse all the nodes of the mold component, select the node with the smallest X coordinate value and the node with the largest X coordinate value as M10; for the influence area mobile node influence8: traverse all the nodes of the mold component, define the node with the smallest X coordinate value and the largest Y coordinate value as base point 1, find the point with the same Y coordinate as base point 1 and the largest X coordinate value, and define it as end point 1, select the node with an X coordinate value greater than base point 1 and less than end point 1, and define it as a subset 1 of the influence area mobile node influence8; traverse all the nodes of the mold component, and define the node with the smallest X coordinate value and the largest Y coordinate value as base point 1. The node with the largest X coordinate value and the largest Y coordinate value is defined as base point 2. The point with the same Y coordinate as base point 2 and the smallest X coordinate value is found and defined as end point 2. The nodes with X coordinate values ​​greater than end point 2 and less than base point 2 are screened and defined as subset 2 of the influence area mobile node influence8. Subset 1 of the influence area mobile node influence8 and subset 2 of the influence area mobile node influence8 constitute the influence area mobile node influence8. The key mobile node M11 is all nodes of the mold component except M10 and influence8.

[0032] Furthermore, the coordinate values ​​of the moving nodes in each component are defined as variables, and the changes in the process parameters of the self-piercing riveting forming process simulation model are realized by changing the coordinate values ​​of the moving nodes of each component. In this process, the changes in each process parameter need to comply with different change criteria, and the change criteria of each component are:

[0033] (1) Rivet size change criteria

[0034] For the rivet length, the control of the rivet length parameter is achieved by changing the Y coordinate value of M4, and the change in the Y coordinate value of the corresponding node influence5 is: the change in the Y coordinate value of M4 divided by L0, where: L0 is the grid unit layer number definition of the mobile node influence5 in the influence area;

[0035] For the rivet tip rake angle, the rivet rake angle variable is converted into the Y value change of node M2: Δβ = Where Δβ is the change in the rivet forward angle, Δy 1 is the change in the Y value of node M2, Y 1 is the initial difference between the Y value of node M2 ​​and the fixed node M1, δ 1 is the absolute value of the initial difference between the X value of node M2 ​​and the fixed node M1, and β is the initial forward tilt angle;

[0036] For the rivet tip back tilt angle, the rivet back tilt angle variable is converted into the Y value change of node M3: Δα = Where Δα is the change in the rivet back angle, α is the initial inclination angle, Δy2 is the Y value change of node M3, Y 2 is the initial difference between the Y value of node M3 and the fixed point M1, δ 2 is the absolute value of the initial difference between the X value of node M3 and the fixed point M1, and β is the initial caster angle;

[0037] The change of the influence zone mobile node influence1 is:

[0038] Δy 3 =tan(Δβ+β)*(δ 3 )-Y 3

[0039] Among them, Δy 3 is the Y value change of the mobile node influence1 in the influence area, Y 3 is the difference between the Y value of the mobile node influence1 in the influence area and the initial value, δ 3 is the difference between the X value of the mobile node influence1 in the influence area and the initial value of the corresponding node;

[0040] The change of the influence zone mobile node influence2 is:

[0041] Δy 4 =tan(Δα+α)*(δ 4 )-Y 4

[0042] Among them, Δy 4 is the Y value change of the mobile node influence2 in the influence area, Y 4 is the difference between the Y value of the mobile node influence2 in the influence area and the initial value, δ 4 is the difference between the X value of the mobile node influence2 in the influence area and the initial value of the corresponding node;

[0043] The change in the Y coordinate value of the mobile node influence3 in the influence area is: the change in the Y coordinate value of the node M2 ​​divided by the number of nodes of the mobile node influence3 in the influence area;

[0044] The change in the Y coordinate value of the mobile node influence4 in the influence area is: the change in the Y coordinate value of the node M3 divided by the number of grid unit layers of the mobile node influence4 in the influence area;

[0045] The change in the Y coordinate value of the influence zone mobile node influence5 is: the change in the Y coordinate value of the node M4 divided by the number of nodes of the influence zone mobile node influence5;

[0046] (2) Mold size change criteria

[0047] For the inner diameter of the mold, the change of the inner diameter parameter of the rivet mold is achieved by controlling the change of the X coordinate value of the key mobile node M11. The change of the X coordinate value of the corresponding influence zone mobile node influence8 is: the change of the X value of the key mobile node M11 divided by L3, where L3 is defined by the number of grid unit layers of the influence zone mobile node influence8;

[0048] (3) Criteria for variation of upper plate thickness

[0049] The change of the thickness parameter of the upper plate is achieved by controlling the change of the Y coordinate value of M7. The corresponding change of the Y coordinate value of the node of influence6 is: the change of the Y coordinate value of M5 divided by L1, where L1 is the definition of the number of layers of the grid unit of the upper plate;

[0050] (4) Criteria for variation of lower plate thickness

[0051] The change of the thickness parameter of the lower plate is achieved by controlling the change of the Y coordinate value of M9. The corresponding change of the Y coordinate value of the node of influence7 is: the change of the Y coordinate value of M9 divided by L2, where L2 is defined as the number of layers of the grid unit of the lower plate.

[0052] Furthermore, the cross-sectional characteristic quality dimensions include rivet head height, interlocking value, remaining thickness and bottom thickness.

[0053] Furthermore, the automatic extraction of the cross-sectional characteristic quality dimensions of the parametric simulation model of the self-piercing riveting forming process is specifically:

[0054] (1) Determine the location of the measurement points of the cross-section characteristic quality dimensions of the parametric simulation model of the self-piercing riveting forming process

[0055] For the rivet head height measurement points P1 and P2, traverse the rivet component node set, filter all nodes whose node X coordinate values ​​are the rivet diameter, and compare the corresponding node Y coordinate values ​​in turn. The node with the largest Y coordinate value is P1. Similarly, filter all nodes whose node X coordinate values ​​are the width of the upper layer in the rivet component node set, and compare the corresponding node Y coordinate values ​​in turn. The node with the largest Y coordinate value is P2.

[0056] For the interlocking value measurement points P3 and P4, traverse the node set of the rivet component, filter all nodes whose Y coordinate values ​​are less than the upper surface of the mold and greater than the step surface of the mold, and the node with the largest X coordinate value is P3; filter all nodes whose X coordinate value is 0, and the node with the largest Y coordinate value is correction point 1. If the Y coordinate value of correction point 1 is greater than the Y value of P3, the P4 screening condition becomes: find all nodes whose Y value of the node of the lower plate component is greater than correction point 1, whose X value is less than P3 and greater than P7, compare the X coordinate values ​​of the nodes in turn, and define the node with the largest X coordinate value as P4; if the Y coordinate value of correction point 1 is less than the Y coordinate value of P3, the P4 screening condition becomes: find all nodes whose Y coordinate value of the node of the lower plate component is greater than P3, whose X coordinate value is less than P3 and greater than P7, compare the X coordinate values ​​of the nodes in turn, and define the node with the smallest X coordinate value as P4;

[0057] For the remaining thickness measurement points P5 and P6, all nodes in the upper plate and the lower plate are traversed, and then the relative distances between all nodes of the upper plate and each node in the lower plate are calculated. When the relative distance between two nodes is the smallest, the two nodes are defined as P5 and P6 respectively.

[0058] For the bottom thickness measurement points P7 and P8, traverse the rivet component node set, and select the node with the smallest Y coordinate value, which is P7; similarly, traverse the lower plate component node set, select all nodes whose X coordinate value and the X coordinate value of P7 are less than the grid unit length, and compare the corresponding node Y coordinate values ​​in turn. The node with the smallest Y coordinate value is P8.

[0059] (2) Calculation of the cross-sectional characteristic mass dimensions of the parametric simulation model of the self-piercing riveting process

[0060] The rivet head height is: the absolute value of the difference between the Y coordinates of the measuring point P1 and the measuring point P2;

[0061] The interlock value is: the absolute value of the difference between the X coordinates of the measuring point P3 and the measuring point P4;

[0062] The remaining thickness is: the relative distance between the measuring point P5 and the measuring point P6;

[0063] The bottom thickness is: the absolute value of the Y coordinate difference between the measuring point P7 and the measuring point P8.

[0064] A full-process joint simulation system for parameterized self-piercing riveting forming process, including:

[0065] Model building module, used to build a simulation model of the self-piercing riveting forming process;

[0066] The parametric model building module parameterizes the coordinates of the moving nodes in the self-piercing riveting forming process simulation model and builds a parametric simulation model;

[0067] Mesh reconstruction module, which reconstructs the mesh of the parametric simulation model of the self-piercing riveting forming process;

[0068] The solution module uses batch scripts to solve and calculate the parametric simulation model of the self-piercing riveting forming process;

[0069] The module for extracting cross-section feature quality dimensions is used to obtain the cross-section feature quality dimensions of the self-piercing riveting forming process simulation model.

[0070] The beneficial effects of the present invention are as follows: the present invention can realize the parameterization of the self-piercing rivet forming process simulation model, the batch calculation and solution of the parameterized simulation model, and the automation of the measurement of the cross-sectional feature quality dimensions of the simulation model, thereby shortening the time for building the self-piercing rivet forming process simulation model under different process parameters, improving the efficiency of extracting simulation results, and being able to provide technical support for application scenarios that require a large amount of sample data, such as the process parameter optimization design of self-piercing rivets, the establishment of a process matching window, and the construction of a process prediction model. BRIEF DESCRIPTION OF THE DRAWINGS

[0071] Figure 1 It is a full-process joint simulation flow chart of the parametric self-piercing riveting forming process of the present invention;

[0072] Figure 2 This is a simulation model diagram of the self-piercing riveting forming process of the present invention;

[0073] Figure 3 It is a schematic diagram of the fixed nodes and the movable nodes of the rivet forward angle and backward angle according to the present invention;

[0074] Figure 4 A schematic diagram of a fixed node and a mobile node for controlling the length of a rivet according to the present invention;

[0075] Figure 5 It is a schematic diagram of the fixed nodes and mobile nodes of the upper plate of the present invention;

[0076] Figure 6 This is a schematic diagram of the fixed nodes and mobile nodes of the lower board of the present invention;

[0077] Figure 7 This is a schematic diagram of the mold fixed nodes and mobile nodes of the present invention;

[0078] Figure 8 It is a schematic diagram of the locations of the characteristic quality dimension measurement points of the cross-section of the simulation model of the self-piercing riveting forming process described in the present invention. DETAILED DESCRIPTION

[0079] The present invention will be further described below in conjunction with the accompanying drawings. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0080] Figure 1 The present invention provides a full-process joint simulation method for a parameterized self-piercing riveting forming process, which specifically includes the following steps:

[0081] Step (1), building a self-piercing riveting forming process simulation model.

[0082] The self-piercing riveting forming process simulation model is established using HyperMesh commercial software. The model includes a punch, a blank holder, a rivet, an upper plate, a lower plate, and a die. The self-piercing riveting forming process simulation model can be a 2D axisymmetric model or a 3D model. In this embodiment, a 2D axisymmetric model is used, such as Figure 2 shown.

[0083] Step (2), parameterizing the coordinates of the moving nodes in the self-piercing rivet forming process simulation model, building a parameterized simulation model, and characterizing the changes in the process parameters of the self-piercing rivet forming process simulation model by the changes in the coordinates of the moving nodes; wherein the process parameters of the self-piercing rivet forming process simulation model include: rivet size, mold size, upper plate thickness and lower plate thickness, the rivet size includes rivet length, rivet tip forward tilt angle and rivet tip backward tilt angle, and the mold size includes mold depth and mold inner diameter.

[0084] Step (2.1), define the fixed nodes and mobile nodes of each component of the self-piercing riveting forming process simulation model and number them; wherein, the fixed nodes and mobile nodes of each component include: rivet fixed nodes and mobile nodes, upper plate fixed nodes and mobile nodes, lower plate fixed nodes and mobile nodes, mold fixed nodes and mobile nodes, and mobile nodes include key mobile nodes and impact zone mobile nodes; the definition method of these nodes is:

[0085] The rivet fixed nodes are defined as M1 and M5, the key mobile nodes are defined as M2, M3 and M4, and the influence area mobile nodes are defined as influence1, influence2, influence3, influence4 and influence5. The rivet forward inclination angle, backward inclination angle fixed nodes and mobile nodes are as follows Figure 3 As shown, the rivet length controls the fixed nodes and the mobile nodes as shown in Figure 4 shown.

[0086] The upper plate fixed node is defined as M6, the key mobile node is defined as M7, and the influence area mobile node is defined as influence6; Figure 5 shown.

[0087] The fixed node of the lower plate is defined as M8, the key mobile node is defined as M9, and the mobile node of the influence area is defined as influence7; Figure 6 shown.

[0088] The mold fixed node is defined as M10, the key mobile node is defined as M11, and the influence area mobile node is defined as influence8; Figure 7 shown.

[0089] Step (2.2) extracts all node information of each component in the model and groups them according to the components. The specific steps are as follows:

[0090] Step (2.2.1), define the local coordinate system of the self-piercing riveting forming process simulation model, take the intersection of the upper surface of the rivet head and its symmetry center as the origin of the local coordinate system, take the direction opposite to the movement of the punch as the positive direction of the Y axis, and take the rivet thickness direction as the positive direction of the X axis.

[0091] Step (2.2.2) extracts all nodes of each component in the model. The specific method is:

[0092] For the rivet fixed node M1, traverse all the node coordinates of the rivet component and take the node with the smallest Y coordinate value as M1; for the key mobile node, define all the nodes of the rivet outer diameter as set A, and take the node with the smallest Y coordinate value in set A as the key mobile node M2; define all the nodes of the rivet inner diameter as set B, and take the node with the smallest Y value in set B as the key mobile node M3;

[0093] For the rivet length key mobile node M4, select the node whose Y coordinate value is greater than the maximum Y coordinate value of the node in set A as M4; for the rivet fixed node M5, select the node whose Y coordinate value is less than or equal to the key mobile node M3 as the rivet fixed node M5;

[0094] For the mobile node influence1 in the influence area, traverse all nodes of the rivet component, select nodes whose Y coordinate values ​​are less than the key moving point M2, and define them as set C; select nodes in set C whose X coordinate values ​​and Y coordinate values ​​are less than the key moving node M2 ​​and the difference is less than the length of the grid unit as node 1; based on the same screening method, use node 1 to find the next node whose X coordinate value and Y coordinate value are less than node 1, and the difference between the X and Y coordinates of node 1 and node 1 is less than the length of the grid unit, as node 2, and iterate in sequence until all mobile nodes in the influence area of ​​influence1 are found;

[0095] For the mobile node influence2 in the influence area, the nodes whose Y coordinate values ​​are less than the key mobile node M3 are filtered and defined as set D. In set D, the nodes whose X coordinate values ​​and Y coordinate values ​​are less than the key mobile node M3 and the difference is less than the length of the grid unit are filtered out in sequence, and the process is repeated until all the points of the mobile node influence2 in the influence area are found; the mobile node influence3 in the influence area is all the nodes in set A after removing M2; the mobile node influence4 in the influence area is all the nodes in set B after removing M3; the mobile node influence5 in the influence area is all the nodes whose Y coordinate value is greater than the rivet key mobile node M3 and less than the maximum point of the node Y coordinate value in set A; the number of grid unit layers of the mobile node influence5 in the influence area is defined as L0.

[0096] For the fixed node M6 of the upper plate, traverse the coordinates of all nodes of the upper plate component, and select the node with the smallest Y coordinate value as M6; for the key mobile node, traverse all nodes of the upper plate component, and select the node with the largest Y coordinate value of the upper plate component and all nodes of the rivet, punch, and blank holder as the key mobile node M7; the influence area mobile node influence6 is all nodes of the upper plate component except M5 and M6; the number of grid unit layers of the upper plate is defined as L1.

[0097] For the fixed node M8 of the lower plate, traverse the coordinates of all nodes of the lower plate component, and select the node with the smallest Y coordinate value as the fixed node M8; for the key mobile node, traverse all nodes of the lower plate component, and select the node with the largest Y coordinate value of the lower plate component as well as the rivet, punch, blank holder and all nodes of the upper plate as the key mobile node M9; the influence area mobile node influence7 is all nodes of the lower plate component except M8 and M9; the number of grid unit layers of the lower plate is defined as L2.

[0098] For the mold fixed node M10, traverse all the nodes of the mold component, select the node with the smallest X coordinate value and the node with the largest X coordinate value as M10; for the influence area mobile node influence8: traverse all the nodes of the mold component, define the node with the smallest X coordinate value and the largest Y coordinate value as base point 1, find the point with the same Y coordinate as base point 1 and the largest X coordinate value, and define it as end point 1; select the nodes with X coordinate values ​​greater than base point 1 and less than end point 1, and define them as subset 1 of the influence area mobile node influence8; traverse all the nodes of the mold component, and define the node with the largest X coordinate value and the largest Y coordinate value as The node is defined as base point 2; find the point with the same Y coordinate as base point 2 and the smallest X coordinate value, and define it as end point 2; filter out nodes with X coordinate values ​​greater than end point 2 and less than base point 2, and define them as subset 2 of influence area mobile node influence8; subset 1 of influence area mobile node influence8 and subset 2 of influence area mobile node influence8 constitute influence area mobile node influence8; key mobile node M11 is all nodes of the mold component except M10 and influence8; the number of grid unit layers of influence area mobile node influence8 is defined as L3.

[0099] Step (2.3) defines the coordinate values ​​of the moving nodes in each component as variables, and changes the coordinate values ​​of the moving nodes of each component to achieve the change of the process parameters of the self-piercing riveting forming process simulation model. In this process, the change of each process parameter needs to comply with different change criteria. The change criteria of each component are:

[0100] The rivet size variation criteria are:

[0101] For the rivet length, the control of the rivet length parameter is achieved by changing the Y coordinate value of M4, and the change in the Y coordinate value of the node corresponding to influence5 is: the change in the Y coordinate value of M4 divided by L0;

[0102] For the rivet tip rake angle, the rivet rake angle variable can be converted into the Y value change of node M2: Where Δβ is the change in the rivet forward angle, Δy 1 is the change in the Y value of node M2, Y 1 is the initial difference between the Y value of node M2 ​​and the fixed node M1, δ 1 is the absolute value of the initial difference between the X value of node M2 ​​and the fixed node M1, and β is the initial forward tilt angle;

[0103] For the rivet tip back angle, the rivet back angle variable can be converted into the Y value change of node M3: Where Δα is the change in the rivet back angle, α is the initial inclination angle, Δy2 is the change in the Y value of node M3, Y 2 is the initial difference between the Y value of node M3 and the fixed point M1, δ 2 is the absolute value of the initial difference between the X value of node M3 and the fixed point M1, and β is the initial caster angle;

[0104] When the front and rear tilt angles change, the mesh smoothness will be affected accordingly. In order to improve the mesh smoothness, the corresponding influence area will also change accordingly. The specific change criteria are as follows:

[0105] When the forward tilt angle changes, the change of node influence1 is:

[0106] Δy 3 =tan(Δβ+β)*(δ 3 )-Y 3

[0107] Among them, Δβ is the change in the rivet front tilt angle, β is the initial front tilt angle, Δy 3 is the Y value change of the mobile node influence1 in the influence area, Y 3 is the difference between the Y value of the mobile node influence1 in the influence area and the initial value, δ 3 It is the difference between the X value of the mobile node influence1 in the influence area and the initial value of the corresponding node.

[0108] When the tilt angle changes, the change of node influence2 is:

[0109] Δy 4 =tan(Δα+α)*(δ 4 )-Y 4

[0110] Among them, Δα is the change in the rivet back tilt angle, α is the initial back tilt angle, Δy 4 is the Y value change of the mobile node influence2 in the influence area, Y 4 is the difference between the Y value of the mobile node influence2 in the influence area and the initial value, δ 4 It is the difference between the X value of the mobile node influence2 in the influence area and the initial value of the corresponding node.

[0111] The change in the Y coordinate value of the influence zone mobile node influence3 is: the change in the Y coordinate value of the node M2 ​​divided by the number of nodes of the influence zone mobile node influence3; the change in the Y coordinate value of the influence zone mobile node influence4 is: the change in the Y coordinate value of the node M3 divided by the number of nodes of the influence zone mobile node influence4; the change in the Y coordinate value of the influence zone mobile node influence5 is: the change in the Y coordinate value of the node M4 divided by the number of grid unit layers of the influence zone mobile node influence5.

[0112] The mold size change criterion is: for the mold inner diameter, the change of the rivet mold inner diameter parameter is achieved by controlling the change in the X coordinate value of the key mobile node M11, and the change in the X coordinate value of the corresponding influence area mobile node influence8 is: the change in the X value of the key mobile node M11 divided by L3.

[0113] The criterion for the change of the thickness of the upper plate is: the change of the thickness parameter of the upper plate is achieved by controlling the change of the Y coordinate value of M7, and the corresponding change of the Y coordinate value of the node of influence6 is: the change of the Y coordinate value of M5 divided by L1.

[0114] The thickness change criterion of the lower plate is: the change of the thickness parameter of the lower plate is achieved by controlling the change of the Y coordinate value of M9, and the corresponding change of the Y coordinate value of the node of influence7 is: the change of the Y coordinate value of M9 divided by L2.

[0115] Step (2.4), output the parameterized self-piercing riveting forming process simulation model file.

[0116] Step (3), reconstructing the mesh of the parametric simulation model of the self-piercing rivet forming process, and repairing the parametric simulation model of the self-piercing rivet forming process.

[0117] The present invention calls the commercial software ANSA and realizes the mesh reconstruction of the parameterized simulation model of the self-piercing riveting forming process by writing a mesh redrawing script.

[0118] Step (4), based on the LS-DYNA solver, a batch script is used to solve the parametric simulation model of the self-piercing riveting forming process after the computational mesh reconstruction, and obtain the node coordinate information of each component in the forming process.

[0119] Step (5), based on the node coordinate information of each component in the forming process, obtain the cross-sectional characteristic quality dimensions of the parametric simulation model of the self-piercing riveting forming process, wherein the cross-sectional characteristic quality dimensions include the interlocking value int, the rivet head height hh, the remaining thickness rt, and the bottom thickness dt.

[0120] Step (5.1), define the cross-sectional characteristic quality dimension measurement points P1-P8 of the self-piercing riveting forming process simulation model, where P1 and P2 are the rivet head height measurement points, P3 and P4 are the interlocking value measurement points, P5 and P6 are the remaining thickness measurement points, and P7 and P8 are the bottom thickness measurement points.

[0121] Step (5.2) determines the position of the measurement point of the cross-section characteristic quality dimension of the parametric simulation model of the self-piercing riveting forming process. The specific method is as follows:

[0122] For the rivet head height measurement points P1 and P2, traverse the rivet component node set, filter all nodes whose node X coordinate values ​​are the rivet diameter, and compare the corresponding node Y coordinate values ​​in turn. The node with the largest Y coordinate value is P1. Similarly, filter all nodes whose node X coordinate values ​​are the width of the upper layer in the rivet component node set, and compare the corresponding node Y coordinate values ​​in turn. The node with the largest Y coordinate value is P2. The specific position is as follows: Figure 8 As shown;

[0123] For the interlocking value measurement points P3 and P4, traverse the rivet component node set, filter all nodes whose Y coordinate values ​​are less than the upper surface of the mold and greater than the step surface of the mold, and the node with the largest X coordinate value is P3; filter all nodes whose X coordinate value is 0, and the node with the largest Y coordinate value is correction point 1. If the Y coordinate value of correction point 1 is greater than the Y value of P3, the P4 screening condition becomes: find all nodes whose Y value of the lower plate component node is greater than correction point 1, whose X value is less than P3 and greater than P7, compare the X coordinate values ​​of the nodes in turn, and the node with the largest X coordinate value is defined as P4; if the Y coordinate value of correction point 1 is less than the Y coordinate value of P3, the P4 screening condition becomes: find all nodes whose Y coordinate value of the lower plate component node is greater than P3, whose X coordinate value is less than P3 and greater than P7, compare the X coordinate values ​​of the nodes in turn, and the node with the smallest X coordinate value is defined as P4. The specific positions are as follows: Figure 8 As shown;

[0124] For the remaining thickness measurement points P5 and P6, all nodes in the upper plate and the lower plate are traversed, and then the relative distances between all nodes in the upper plate and each node in the lower plate are calculated. When the relative distance between two nodes is the smallest, the two nodes are defined as P5 and P6 respectively. The specific positions are as follows: Figure 8 As shown;

[0125] For the bottom thickness measurement points P7 and P8, traverse the rivet component node set, and select the node with the smallest Y coordinate value, which is P7; similarly, traverse the lower plate component node set, select all nodes whose X coordinate value and the difference between the X coordinate value of P7 are less than the grid unit length, and compare the corresponding node Y coordinate values ​​in turn. The node with the smallest Y coordinate value is P8. The specific location is as follows: Figure 8 shown.

[0126] Step (5.3), calculate the characteristic mass dimensions of the cross-section of the self-piercing riveting forming process simulation model.

[0127] The rivet head height measurement point, interlocking value measurement point, remaining thickness measurement point and bottom thickness measurement point obtained in step (5.2) are calculated according to the cross-sectional characteristic quality dimension calculation standard (Table 1) to obtain the cross-sectional characteristic quality dimension of the self-piercing riveting forming process simulation model.

[0128] Table 1 Calculation standard of section characteristic quality dimensions

[0129]

[0130] The following uses 100 sets of self-piercing riveting forming process simulation models with different process parameter combinations, and compares the results of the manual method (manual adjustment of process parameters and manual calculation to obtain the quality dimensions of the cross-section characteristics) and the full-process joint simulation method of a parameterized self-piercing riveting forming process of the present invention. The process parameter combinations are: the range of the forward tilt angle of the rivet is ±0.2°, the range of the backward tilt angle of the rivet is ±0.2°, the range of the rivet length is ±0.6mm, the range of the thickness of the upper plate is ±0.4mm, the range of the thickness of the lower plate is ±0.2mm, and the range of the inner diameter of the mold is ±0.4mm. The process parameters of each component can take any rational number within the range of variation. Table 2 shows the time comparison of different processing methods of the self-piercing riveting forming process simulation model. For building simulation model samples with 100 different process parameter combinations, the time required by the present invention is 0.2 hours, which is 96.7% higher than the manual processing efficiency; for extracting the cross-sectional characteristic quality dimensions of the simulation result models with 100 different process parameter combinations, the time required by the present invention is 2 hours, which is 50% higher than the manual processing efficiency.

[0131] Table 2 Time comparison of different processing methods in the simulation model of self-piercing riveting process

[0132]

[0133] The full-process joint simulation method of a parametric self-piercing rivet forming process proposed in this embodiment can realize the full-process automation of the self-piercing rivet forming process, including automatically constructing a parametric simulation model of the self-piercing rivet forming process, automatically submitting a solution to calculate the parametric simulation model of the self-piercing rivet forming process, and automatically extracting the cross-sectional feature quality dimensions of the simulation model. It is no longer necessary to manually build the model and extract the simulation result data, which improves the data processing efficiency and reduces human errors. In addition, the present invention can provide technical support for application scenarios that require a large amount of sample data, such as the process parameter optimization design of self-piercing rivets, the construction of process matching windows, and the construction of process prediction models.

[0134] A full-process joint simulation system for parameterized self-piercing riveting forming process, including:

[0135] Model building module, used to build a simulation model of the self-piercing riveting forming process;

[0136] The parametric model building module parameterizes the coordinates of the moving nodes in the self-piercing riveting forming process simulation model and builds a parametric simulation model;

[0137] Mesh reconstruction module, which reconstructs the mesh of the parametric simulation model of the self-piercing riveting forming process;

[0138] The solution module uses batch scripts to solve and calculate the parametric simulation model of the self-piercing riveting forming process;

[0139] A module for obtaining cross-section feature quality dimensions is used to obtain cross-section feature quality dimensions of a self-piercing riveting forming process simulation model.

[0140] Based on the same inventive concept as a full-process joint simulation method for a parameterized self-piercing riveting forming process, the present application also provides an electronic device, which includes one or more processors and one or more memories, wherein a computer-readable code is stored in the memory, wherein the computer-readable code, when executed by one or more processors, implements a full-process joint simulation method for a parameterized self-piercing riveting forming process of the present invention. Among them, the memory may include a non-volatile storage medium and an internal memory; the non-volatile storage medium may store an operating system and a computer-readable code. The computer-readable code includes program instructions, which, when executed, can enable the processor to execute any full-process joint simulation method for a parameterized self-piercing riveting forming process. The processor is used to provide computing and control capabilities to support the operation of the entire electronic device. The memory provides an environment for the operation of the computer-readable code in the non-volatile storage medium, and when the computer-readable code is executed by the processor, the processor can execute any full-process joint simulation method for a parameterized self-piercing riveting forming process.

[0141] It should be understood that the processor may be a central processing unit (CPU), and the processor may also be other general-purpose processors, digital signal processors (DSP), application-specific integrated circuits (ASIC), field-programmable gate arrays (FPGA) or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc. Among them, the general-purpose processor may be a microprocessor or the processor may also be any conventional processor, etc.

[0142] The computer-readable storage medium may be an internal storage unit of the electronic device described in the aforementioned embodiment, such as a hard disk or memory of the computer device. The computer-readable storage medium may also be an external storage device of the electronic device, such as a plug-in hard disk, a smart memory card (SmartMedia Card, SMC), a secure digital (Secure Digital, SD) card, a flash card (Flash Card), etc. equipped on the electronic device.

[0143] The above embodiments are only used to illustrate the design ideas and features of the present invention, and their purpose is to enable those skilled in the art to understand the content of the present invention and implement it accordingly. The protection scope of the present invention is not limited to the above embodiments. Therefore, any equivalent changes or modifications made based on the principles and design ideas disclosed by the present invention are within the protection scope of the present invention.

Claims

1. A full-process joint simulation method for parameterized self-piercing riveting forming process, characterized in that: Build a simulation model of the self-piercing riveting process; Parameterizing the coordinates of the moving nodes in the self-piercing rivet forming process simulation model, building a parameterized simulation model of the self-piercing rivet forming process, and characterizing the changes in the process parameters of the self-piercing rivet forming process simulation model through the changes in the coordinates of the moving nodes; Reconstructing the mesh of the parametric simulation model of the self-piercing riveting forming process; Based on the batch script, the parametric simulation model of the self-piercing riveting forming process after the computational grid reconstruction is solved to obtain the node coordinate information of each component in the forming process; Based on the node coordinate information of each component in the forming process, the cross-sectional characteristic mass size of the parametric simulation model of the self-piercing riveting forming process is obtained; The coordinate parameterization of the moving nodes in the self-piercing riveting forming process simulation model is as follows: Define the fixed nodes and mobile nodes of each component of the self-piercing riveting forming process simulation model and number them; the mobile nodes include key mobile nodes and impact area mobile nodes; Extract all node information of each component in the self-piercing riveting forming process simulation model and group them according to the components; The coordinate values ​​of the moving nodes in each component are defined as variables, and the process parameters of the self-piercing rivet forming process simulation model are changed by changing the coordinate values ​​of the moving nodes of each component, so as to obtain a parameterized simulation model of the self-piercing rivet forming process; The process parameters of the self-piercing riveting forming process simulation model include: rivet size, mold size, upper plate thickness and lower plate thickness, the rivet size includes rivet length, rivet tip forward angle, rivet tip backward angle, and the mold size includes mold depth and mold inner diameter; The fixed nodes and mobile nodes of each component include rivet fixed nodes and mobile nodes, upper plate fixed nodes and mobile nodes, lower plate fixed nodes and mobile nodes, and mold fixed nodes and mobile nodes; and: The rivet fixed nodes are defined as M1 and M5, the key mobile nodes are defined as M2, M3 and M4, and the influence zone mobile nodes are defined as influence1, influence2, influence3, influence4 and influence5; The upper plate fixed node is defined as M6, the key mobile node is defined as M7, and the influence zone mobile node is defined as influence6; The fixed node of the lower slab is defined as M8, the key mobile node is defined as M9, and the mobile node in the influence area is defined as influence7; The mold fixed node is defined as M10, the key mobile node is defined as M11, and the influence area mobile node is defined as influence8.

2. The full-process joint simulation method of the parametric self-piercing riveting forming process according to claim 1 is characterized in that: The self-piercing riveting forming process simulation model includes the following components: Punch, blank holder, rivet, upper plate, lower plate and die.

3. The full-process joint simulation method of the parametric self-piercing riveting forming process according to claim 1 is characterized in that: The method of extracting all node information of each component in the model and grouping them according to the components is as follows: (1) Define the local coordinate system of the self-piercing riveting process simulation model, with the intersection of the upper surface of the rivet head and its symmetry center as the origin of the local coordinate system, the direction opposite to the movement of the punch as the positive direction of the Y axis, and the rivet thickness direction as the positive direction of the X axis; (2) Extract all nodes of each component in the model and group them by component For the rivet fixed node M1, traverse all the node coordinates of the rivet component and take the node with the smallest Y coordinate value as M1; for the key mobile node, define all the nodes of the rivet outer diameter as set A, and take the node with the smallest Y value in set A as the key mobile node M2; define all the nodes of the rivet inner diameter as set B, and take the node with the smallest Y value in set B as the key mobile node M3; For the rivet length key mobile node M4, select the node whose Y coordinate value is greater than the largest node Y value in set A as M4; for the rivet fixed node M5, select the node whose Y coordinate value is less than or equal to the key mobile node M3 as the rivet fixed node M5; For the mobile node influence1 in the influence area, traverse all nodes of the rivet component, select nodes whose Y coordinate values ​​are less than the key moving point M2 and define them as set C, and select nodes in set C whose X coordinate values ​​and Y coordinate values ​​are less than the key moving point M2 and the difference is less than the length of the grid unit as node 1; based on the same screening method, use node 1 to find the next node whose X coordinate value and Y coordinate value are less than node 1, and the difference between the X and Y coordinates of node 1 and node 1 is less than the length of the grid unit, as node 2, and iterate in sequence until all mobile nodes in the influence area of ​​influence1 are found; For the mobile node influence2 in the influence area, the nodes whose Y coordinate value is less than the key mobile node M3 are filtered and defined as set D. In set D, the nodes whose X coordinate value and Y coordinate value are less than the key mobile node M3 and the difference is less than the length of the grid unit are filtered out in sequence until all the points of the mobile node influence2 in the influence area are found; the mobile node influence3 in the influence area is all the nodes in set A after removing M2; the mobile node influence4 in the influence area is all the nodes in set B after removing M3; the mobile node influence5 in the influence area is all the nodes whose Y coordinate value is greater than the rivet key mobile node M3 and less than the maximum Y coordinate value of the node in set A; For the upper plate fixed node M6, traverse all the node coordinates of the upper plate component, and select the node with the smallest Y coordinate value as M6; for the key mobile node, traverse all the nodes of the upper plate component, and select the node with the largest Y coordinate value of the upper plate component and all the nodes of the rivet, punch, and blank holder as the key mobile point M7; the influence area mobile node influence6 is all the nodes of the upper plate component except M5 and M6; For the fixed node M8 of the lower plate, all the node coordinates of the lower plate components are traversed, and the node with the smallest Y coordinate value is selected as the fixed node M8; for the key mobile node, all the nodes of the lower plate components are traversed, and the node with the largest Y coordinate value of the lower plate components, as well as the rivet, punch, blank holder and all the nodes of the upper plate are selected as the key mobile node M9; the mobile node influence7 in the influence area is all the nodes of the lower plate components except M8 and M9; For the mold fixed node M10, traverse all the nodes of the mold component, select the node with the smallest X coordinate value and the node with the largest X coordinate value as M10; for the influence area mobile node influence8: traverse all the nodes of the mold component, define the node with the smallest X coordinate value and the largest Y coordinate value as base point 1, find the point with the same Y coordinate as base point 1 and the largest X coordinate value, and define it as end point 1, select the node with an X coordinate value greater than base point 1 and less than end point 1, and define it as a subset 1 of the influence area mobile node influence8; traverse all the nodes of the mold component, and define the node with the smallest X coordinate value and the largest Y coordinate value as base point 1. The node with the largest X coordinate value and the largest Y coordinate value is defined as base point 2. The point with the same Y coordinate as base point 2 and the smallest X coordinate value is found and defined as end point 2. The nodes with X coordinate values ​​greater than end point 2 and less than base point 2 are screened and defined as subset 2 of the influence area mobile node influence8. Subset 1 of the influence area mobile node influence8 and subset 2 of the influence area mobile node influence8 constitute the influence area mobile node influence8. The key mobile node M11 is all nodes of the mold component except M10 and influence8.

4. The full-process joint simulation method of the parametric self-piercing riveting forming process according to claim 3 is characterized in that: The coordinate values ​​of the moving nodes in each component are defined as variables, and the changes in the process parameters of the self-piercing riveting forming process simulation model are achieved by changing the coordinate values ​​of the moving nodes of each component. In this process, the changes in each process parameter need to comply with different change criteria. The change criteria of each component are: (1) Rivet size change criteria For the rivet length, the control of the rivet length parameter is achieved by changing the Y coordinate value of M4, and the change in the Y coordinate value of the corresponding node influence5 is: the change in the Y coordinate value of M4 divided by L0, where: L0 is the grid unit layer number definition of the mobile node influence5 in the influence area; For the rivet tip rake angle, the rivet rake angle variable is converted into the Y value change of node M2: Where Δβ is the change in the rivet front tilt angle, αy1 is the change in the Y value of node M2, Y1 is the initial difference between the Y value of node M2 ​​and the fixed node M1, δ1 is the absolute value of the initial difference between the X value of node M2 ​​and the fixed node M1, and β is the initial front tilt angle; For the rivet tip back angle, the rivet back angle variable is converted into the Y value change of node M3: Where Δα is the change in the rivet back-tilt angle, α is the initial inclination angle, Δy2 is the change in the Y value of the node M3, Y2 is the initial difference between the Y value of the node M3 and the fixed point M1, δ2 is the absolute value of the initial difference between the X value of the node M3 and the fixed point M1, and β is the initial back-tilt angle; The change of the influence zone mobile node influence1 is: Δy3=tan(Δβ+β)*(δ3)-Y3 Among them, Δy3 is the change in the Y value of the mobile node influence1 in the influence area, Y3 is the difference between the Y value of the mobile node influence1 in the influence area and the initial value, and δ3 is the difference between the X value of the mobile node influence1 in the influence area and the initial value of the corresponding node; The change of the influence zone mobile node influence2 is: Δy4=tan(Δα+α)*(δ4)-Y4 Among them, Δy4 is the change in the Y value of the mobile node influence2 in the influence area, Y4 is the difference between the Y value of the mobile node influence2 in the influence area and the initial value, and δ4 is the difference between the X value of the mobile node influence2 in the influence area and the initial value of the corresponding node; The change in the Y coordinate value of the mobile node influence3 in the influence area is: the change in the Y coordinate value of the node M2 ​​divided by the number of nodes of the mobile node influence3 in the influence area; The change amount of the Y coordinate value of the influence area mobile node influence4 is: the change amount of the Y coordinate value of the node M3 divided by the number of nodes of the influence area mobile node influence4; The change in the Y coordinate value of the mobile node influence5 in the influence area is: the change in the Y coordinate value of the node M4 divided by the number of grid unit layers of the mobile node influence5 in the influence area; (2) Mold size change criteria For the inner diameter of the mold, the change of the inner diameter parameter of the rivet mold is achieved by controlling the change of the X coordinate value of the key mobile node M11. The change of the X coordinate value of the corresponding influence zone mobile node influence8 is: the change of the X value of the key mobile node M11 divided by L3, where L3 is defined by the number of grid unit layers of the influence zone mobile node influence8; (3) Criteria for variation of upper plate thickness The change of the thickness parameter of the upper plate is achieved by controlling the change of the Y coordinate value of M7. The corresponding change of the Y coordinate value of the node of influence6 is: the change of the Y coordinate value of M5 divided by L1, where L1 is the definition of the number of layers of the grid unit of the upper plate; (4) Criteria for variation of lower plate thickness The change of the thickness parameter of the lower plate is achieved by controlling the change of the Y coordinate value of M9. The corresponding change of the Y coordinate value of the node of influence7 is: the change of the Y coordinate value of M9 divided by L2, where L2 is defined as the number of layers of the grid unit of the lower plate.

5. The full-process joint simulation method of the parametric self-piercing riveting forming process according to claim 1 is characterized in that: The cross-sectional characteristic quality dimensions include rivet head height, interlock value, remaining thickness and bottom thickness.

6. The full-process joint simulation method of the parametric self-piercing riveting forming process according to claim 5 is characterized in that: The step of obtaining the cross-sectional characteristic quality dimensions of the parametric simulation model of the self-piercing riveting forming process is specifically as follows: (1) Determine the location of the measurement points of the cross-section characteristic quality dimensions of the parametric simulation model of the self-piercing riveting forming process For the rivet head height measurement points P1 and P2, traverse the rivet component node set, filter all nodes whose node X coordinate values ​​are the rivet diameter, and compare the corresponding node Y coordinate values ​​in turn. The node with the largest Y coordinate value is P1. Similarly, filter all nodes whose node X coordinate values ​​are the width of the upper layer in the rivet component node set, and compare the corresponding node Y coordinate values ​​in turn. The node with the largest Y coordinate value is P2. For the interlocking value measurement points P3 and P4, traverse the rivet component node set, filter all nodes whose Y coordinate values ​​are less than the upper surface of the mold and greater than the upper step surface of the mold, and the node with the largest X coordinate value is P3; filter all nodes whose X coordinate value is 0, and the node with the largest Y coordinate value is correction point 1. If the Y coordinate value of correction point 1 is greater than the Y value of P3, the P4 screening condition becomes: find all nodes whose Y value of the lower plate component node is greater than correction point 1, whose X value is less than P3 and greater than P7, and compare the X coordinate values ​​of the nodes in turn. The node with the largest X coordinate value is defined as P4; If the Y coordinate value of correction point 1 is less than the Y coordinate value of P3, the P4 screening condition becomes: find all nodes whose Y coordinate value of the lower plate component node is greater than P3, whose X coordinate value is less than P3 and greater than P7, compare the X coordinate values ​​of the nodes in turn, and the node with the smallest X coordinate value is defined as P4; For the remaining thickness measurement points P5 and P6, all nodes in the upper plate and the lower plate are traversed, and then the relative distances between all nodes of the upper plate and each node in the lower plate are calculated. When the relative distance between two nodes is the smallest, the two nodes are defined as P5 and P6 respectively. For the bottom thickness measurement points P7 and P8, traverse the rivet component node set, and select the node with the smallest Y coordinate value, which is P7; similarly, traverse the lower plate component node set, select all nodes whose X coordinate value and the X coordinate value of P7 are less than the grid unit length, and compare the corresponding node Y coordinate values ​​in turn. The node with the smallest Y coordinate value is P8. (2) Calculation of the cross-sectional characteristic mass dimensions of the parametric simulation model of the self-piercing riveting process The rivet head height is: the absolute value of the difference between the Y coordinates of the measuring point P1 and the measuring point P2; The interlock value is: the absolute value of the difference between the X coordinates of the measuring point P3 and the measuring point P4; The remaining thickness is: the relative distance between the measuring point P5 and the measuring point P6; The bottom thickness is: the absolute value of the Y coordinate difference between the measuring point P7 and the measuring point P8.

7. A system for implementing the full-process joint simulation method of the parametric self-piercing riveting forming process according to any one of claims 1 to 6, characterized in that: include: Model building module, used to build a simulation model of the self-piercing riveting forming process; The parametric model building module parameterizes the coordinates of the moving nodes in the self-piercing riveting forming process simulation model and builds a parametric simulation model; Mesh reconstruction module, which reconstructs the mesh of the parametric simulation model of the self-piercing riveting forming process; The solution module uses batch scripts to solve and calculate the parametric simulation model of the self-piercing riveting forming process; A module for obtaining cross-section feature quality dimensions is used to obtain cross-section feature quality dimensions of a self-piercing riveting forming process simulation model.

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