A vehicle body simulation method and related device

Abstract

The present application discloses a vehicle body simulation method and related devices, relating to the field of data processing. The present application determines the material constitutive curve groups of each first casting simulation unit of each vehicle body part involved in the vehicle body to be simulated by using the mechanical property prediction results at a specified strain rate obtained from the vehicle body part casting simulation, which reflect the mechanical properties of each position of each vehicle body part at different strain rates. Based on this mapping, the material constitutive curve groups of each vehicle body simulation unit constituting the vehicle body to be simulated are obtained, providing detailed data support for subsequent vehicle body simulation calculations, and improving the accuracy of vehicle body simulation by means of differential material property parameters that match the actual situation.

Description

Technical Field

[0001] The present application relates to the technical field of data processing, and particularly relates to a vehicle body simulation method and related devices. Background Art

[0002] Vehicle body simulation may refer to predicting and calculating the mechanical behavior of a vehicle body structure under conditions such as collision, for example, finite element collision simulation. When performing vehicle body simulation, it is necessary to import material data of the vehicle body. The currently imported material data is generally uniform, that is, it is assumed that the material properties at each vehicle body position are the same.

[0003] However, the vehicle body parts are mainly manufactured by casting processes. During the casting process of parts that gradually change from a liquid state to a solid state, affected by factors such as material properties, flow process, and solidification process, the finally manufactured castings often have different material properties and exhibit different mechanical properties at different parts, that is, there are differences in the actual material properties at each vehicle body position.

[0004] Therefore, the vehicle body simulation results obtained based on uniform material data usually deviate greatly from the actual results; based on this, how to improve the accuracy of vehicle body simulation has become a technical problem that needs to be urgently solved by those skilled in the art. Summary of the Invention

[0005] In view of the above problems, the present application provides a vehicle body simulation method and related devices to improve the accuracy of vehicle body simulation.

[0006] The specific solutions are as follows:

[0007] The first aspect of the present application provides a vehicle body simulation method, including:

[0008] Obtaining casting simulation data that matches the mechanical test results of each vehicle body part; each of the vehicle body parts is a part related to the vehicle body to be simulated, and the casting simulation data of each vehicle body part includes the mechanical property prediction data of each first casting simulation unit that constitutes the current part at a specified strain rate, and the specified strain rate is the strain rate corresponding to the mechanical test result;

[0009] Determining the mechanical property data of each first casting simulation unit based on the obtained casting simulation data, and generating a material constitutive curve group for each first casting simulation unit; the material constitutive curve corresponding to the specified strain rate in the material constitutive curve group of each first casting simulation unit matches the mechanical property data of the current first casting simulation unit;

[0010] Mapping, based on the material constitutive curve groups of the first casting simulation units, to obtain material constitutive curve groups of each vehicle body simulation unit for performing vehicle body simulation calculations; each of the vehicle body simulation units constitutes the vehicle body to be simulated.

[0011] In a possible implementation, determining the mechanical property data of each first casting simulation unit based on the obtained casting simulation data includes:

[0012] Taking the mechanical property prediction data of each first casting simulation unit in the obtained casting simulation data as data objects to be clustered, and performing clustering processing;

[0013] Determining the mechanical property data of each first casting simulation unit; the mechanical property data of each first casting simulation unit is the mechanical property data of the clustering center to which the current first casting simulation unit belongs, and the mechanical property data of each clustering center is determined based on the data objects constituting the cluster where the current clustering center is located.

[0014] In a possible implementation, the mechanical property data of each clustering center is the mean value of the data objects constituting the cluster where the current clustering center is located.

[0015] In a possible implementation, generating the material constitutive curve groups of each first casting simulation unit includes performing the following steps on each first casting simulation unit:

[0016] Determining a geometric transformation method; the curve obtained by performing geometric transformation on a specified reference curve according to the geometric transformation method matches the mechanical property data of the current first casting simulation unit, and the specified reference curve is the material constitutive curve in the reference material constitutive curve group corresponding to the specified strain rate;

[0017] Performing geometric transformation on each curve in the reference material constitutive curve group according to the geometric transformation method to obtain the material constitutive curve group of the current first casting simulation unit.

[0018] In a possible implementation, mapping to obtain the material constitutive curve groups of each vehicle body simulation unit based on the material constitutive curve groups of each first casting simulation unit includes:

[0019] Determining the data storage nodes of the material constitutive curve groups of each first casting simulation unit as first nodes, and forming a first node set from the first nodes;

[0020] Performing the following steps on each vehicle body simulation unit:

[0021] Determining the data storage node of the current vehicle body simulation unit as a second node;

[0022] Determining n1 first nodes around the second node from the first node set; where n1 is a preset positive integer;

[0023] Interpolate the material constitutive curve groups of the determined n1 first nodes to obtain the material constitutive curve groups of the current vehicle body simulation units.

[0024] In a possible implementation, the casting simulation data of each vehicle body part further includes: the predicted data of the casting residual stress of each second casting simulation unit that makes up the current part, and the predicted data of the casting residual stress is obtained through casting deformation simulation; the method further includes:

[0025] Map the predicted data of the casting residual stress of each second casting simulation unit to obtain the casting residual stress data of each vehicle body simulation unit for performing the vehicle body simulation calculation.

[0026] In a possible implementation, the mapping the predicted data of the casting residual stress of each second casting simulation unit to obtain the casting residual stress data of each vehicle body simulation unit includes:

[0027] Determine the data storage nodes of the predicted data of the casting residual stress of each second casting simulation unit as the third nodes, and form a third node set by each third node;

[0028] Perform the following steps for each vehicle body simulation unit:

[0029] Determine the data storage node of the current vehicle body simulation unit as the second node;

[0030] Determine n2 third nodes around the second node from the third node set; where n2 is a preset positive integer;

[0031] Interpolate the predicted data of the casting residual stress of the determined n2 third nodes to obtain the casting residual stress data of the current vehicle body simulation unit.

[0032] The second aspect of the present application provides a vehicle body simulation device, including:

[0033] A data acquisition unit, configured to acquire casting simulation data matching the mechanical test results of each vehicle body part; each vehicle body part is a part related to the vehicle body to be simulated, and the casting simulation data of each vehicle body part includes the mechanical property prediction data of each first casting simulation unit that makes up the current part at a specified strain rate, and the specified strain rate is the strain rate corresponding to the mechanical test result;

[0034] A data processing unit, configured to determine the mechanical property data of each first casting simulation unit according to the acquired casting simulation data, and generate a material constitutive curve group of each first casting simulation unit; the material constitutive curve corresponding to the specified strain rate in the material constitutive curve group of each first casting simulation unit matches the mechanical property data of the current first casting simulation unit;

[0035] The data processing unit is further configured to map, according to the material constitutive curve groups of the first casting simulation units, to obtain the material constitutive curve groups of the body simulation units for performing body simulation calculations; the body simulation units constitute the body to be simulated.

[0036] In a possible implementation, the data acquisition unit includes a casting simulation unit, which is configured to perform the following steps for each body part related to the body to be simulated:

[0037] Configure the casting simulation parameters of the current body part;

[0038] Perform a casting simulation on the current body part to predict the mechanical properties of the current body part;

[0039] Determine whether the casting simulation data of the current body part predicted is matched with the mechanical test result of the current body part. If so, output the casting simulation data of the current body part; otherwise, return to execute the step of configuring the casting simulation parameters of the current body part.

[0040] A third aspect of the present application provides an electronic device, including at least one processor and a memory connected to the processor, where:

[0041] The memory is used to store a computer program;

[0042] The processor is configured to execute the computer program so that the electronic device can implement the body simulation method according to the first aspect or any implementation manner of the first aspect.

[0043] A fourth aspect of the present application provides a computer program product, including computer-readable instructions, which when running on an electronic device, enable the electronic device to implement the body simulation method according to the first aspect or any implementation manner of the first aspect.

[0044] By means of the above technical solution, the body simulation solution provided by the present application uses the mechanical property prediction results at a specified strain rate obtained from the casting simulation of body parts to determine the material constitutive curve groups of the first casting simulation units of each body part involved in the body to be simulated, reflecting the mechanical properties at different positions of each body part at different strain rates. Based on this, the material constitutive curve groups of the body simulation units constituting the body to be simulated are mapped, providing detailed data support for subsequent body simulation calculations, and improving the accuracy of body simulation by means of differentiated material property parameters that match the actual situation. Description of the Drawings

[0045] With reference to the accompanying drawings and the following specific embodiments, the features, advantages and other aspects of the embodiments of the present disclosure will become clear to those of ordinary skill in the art. Throughout the drawings, the same or similar reference numerals denote the same or similar elements. It should be understood that the drawings are schematic and are only used to show the preferred embodiments, and are not considered to be a limitation on the present application. In the drawings:

[0046] Figure 1 It is a schematic flow chart of a vehicle body simulation method provided by the present application;

[0047] Figure 2 It exemplifies a schematic diagram of a material constitutive curve;

[0048] Figure 3 It shows a schematic diagram of the uniaxial tensile strength distribution of a vehicle body to be simulated;

[0049] Figure 4 It shows a schematic diagram of the yield strength distribution of a vehicle body to be simulated;

[0050] Figure 5 It shows a schematic diagram of the elongation distribution of a vehicle body to be simulated;

[0051] Figure 6 It shows a schematic flow chart of integrated chain simulation of a cast vehicle body;

[0052] Figure 7 It is a schematic structural diagram of a vehicle body simulation device provided by the present application;

[0053] Figure 8 It is a schematic structural diagram of an electronic device provided by the present application. Specific embodiments

[0054] The technical solutions in the embodiments of the present application will be described below with reference to the accompanying drawings in the embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present application without creative efforts shall fall within the protection scope of the present application.

[0055] The embodiments of the present application provide a vehicle body simulation method and related devices to solve the problem of data loss in vehicle body simulation tasks, especially the problem of data loss of material properties, so as to improve the accuracy of vehicle body simulation.

[0056] Figure 1 It is a schematic flow chart of a vehicle body simulation method shown according to the embodiments of the present application. Combining Figure 1 As shown, the method may include:

[0057] Step S101: Obtain casting simulation data that matches the mechanical test results of each vehicle body part.

[0058] Among them, each vehicle body part is a part related to the vehicle body to be simulated. It should be noted that since the casting processes, material properties, etc. of different vehicle body parts are often different, casting simulations are usually carried out on a part-by-part basis; while for vehicle body simulations, such as finite element collision simulations, the entire set of components related to the vehicle body in white need to be connected into a whole through element binding for simulation calculations. That is, the simulation scope of the subsequent vehicle body simulation includes each vehicle body part related to the vehicle body to be simulated. Based on this, obtaining the casting simulation data of each vehicle body part can provide data support for the subsequent vehicle body simulation.

[0059] In addition, when performing casting simulations on vehicle body parts, the vehicle body parts to be simulated are usually divided into several mesh elements for numerical simulation calculations. Among them, the mesh elements can be called casting simulation units. It should be noted that based on different types of casting parameters predicted by the casting simulation, the mesh division methods may vary. Based on this, the mesh elements used when predicting the mechanical properties of castings based on vehicle body parts can be called the first casting simulation units. It should be noted that this application does not limit the simulation units, and the forms, data storage methods, etc. of the simulation units can all refer to existing simulation operations. Based on the foregoing content, the casting simulation data of each vehicle body part can include the mechanical property prediction data of each first casting simulation unit that makes up the current part at a specified strain rate, where the specified strain rate is the strain rate corresponding to the mechanical test result. Specifically, the parameter types involved in the mechanical test results, mechanical property prediction data, mechanical property data, etc. described in this application can include: uniaxial tensile strength, yield strength, and elongation.

[0060] The mechanical tests of vehicle body parts are generally carried out according to certain standards to ensure the consistency and comparability of the test results. The obtained mechanical test results are the test results under the corresponding standards. The mechanical test results of vehicle body parts are obtained by testing the test samples according to the standards. Exemplarily, the test samples can correspond to specified points on the vehicle body parts. The mechanical test results of the test samples can only reflect the actual mechanical properties of the vehicle body parts to a certain extent. Limited by the casting process, they cannot reflect the actual mechanical properties at each part location.

[0061] To ensure the accuracy and reliability of the prediction results obtained from the casting simulation of vehicle body parts, the prediction results can be corrected by combining the mechanical test results of the vehicle body parts. Specifically, the casting simulation process can be adjusted to make the predicted mechanical property results obtained from the casting simulation match the mechanical test results, such as the predicted mechanical property results at specified points matching the mechanical test results. Exemplarily, the above adjustment of the casting simulation process can be carried out according to the test standard followed by the mechanical test results. On the basis of the foregoing content, taking a certain vehicle body part A as an example, the casting simulation data of the vehicle body part A obtained in step S101 that matches the mechanical test results of the vehicle body part A can refer to the data under the current mechanical test result standard, or can also be called the data under the first test standard, and the first test standard is the test standard followed by the mechanical test results in step S101.

[0062] Based on this, the casting simulation data matching the mechanical test results of each vehicle body part in this embodiment provides accurate, reliable and rich predicted mechanical property data for the subsequent vehicle body simulation, providing a basis for improving the accuracy of the vehicle body simulation.

[0063] Step S102, determine the mechanical property data of each first casting simulation unit according to the obtained casting simulation data, and generate a set of material constitutive curves for each first casting simulation unit.

[0064] Each of the first casting simulation units in step S102 includes each first casting simulation unit of each vehicle body part related to the vehicle body to be simulated. Exemplarily, determining the mechanical property data of each first casting simulation unit according to the obtained casting simulation data may include: respectively determining the predicted mechanical property data of each first casting simulation unit obtained as the mechanical property data of each first casting simulation unit.

[0065] It should be noted that there is a large gap between the mechanical data obtained from the casting simulation and the mechanical data required for the vehicle body simulation. When performing vehicle body simulation, each unit requires a set of material constitutive curves. This set of material constitutive curves (that is, the material constitutive curve set described in this application, or can also be called the material constitutive curve family) is composed of material constitutive curves at different strain rates. Any material constitutive curve has stress as the vertical axis and strain as the horizontal axis, so it can also be called a stress-strain curve. Based on this, compared with the mechanical data required for the vehicle body simulation, the mechanical data obtained from the casting simulation has a large lack in terms of data volume and data information, and cannot directly map to obtain the data required for the vehicle body simulation; that is to say, it is necessary to expand and rewrite the mechanical data obtained from the casting simulation to generate a set of material constitutive curves.

[0066] The generated set of material constitutive curves satisfies the following conditions: the material constitutive curve corresponding to the specified strain rate in the set of material constitutive curves of each first casting simulation unit matches the mechanical property data of the current first casting simulation unit; this condition is also the basis for generating the set of material constitutive curves in step S102.

[0067] Next, the types of mechanical property parameters involved in this application (uniaxial tensile strength, yield strength, and elongation) will be described separately. The uniaxial tensile strength may refer to the maximum engineering stress that a component can withstand under unidirectional tension, corresponding to the peak point on the stress-strain curve; the yield strength may refer to the minimum stress value when the component begins to undergo permanent plastic deformation. In practical applications, the stress when the component produces 0.2% plastic strain can also be used as the yield strength. In addition, the upper yield strength or the lower yield strength can also be used as the yield strength. The upper yield strength refers to the maximum stress before the force first drops when the component yields, and the lower yield strength refers to the minimum stress when the initial instantaneous effect is not considered during the yield of the component. The specific definition of the yield strength is not limited in this application; the elongation may refer to the percentage of permanent elongation of the gauge length after the component fractures under tension, reflecting the plastic deformation ability, corresponding to the maximum strain value in the stress-strain curve.

[0068] Based on the above content, Figure 2 A schematic diagram of a material constitutive curve is exemplified. Figure 2 The shown curve has stress as the vertical axis with the stress unit being megapascals (MPa) and strain as the horizontal axis with the strain unit being millimeters per millimeter (mm / mm), in which the data point P1 representing the uniaxial tensile strength, the data point P2 representing the yield strength, and the data point P3 representing the elongation are shown.

[0069] The set of material constitutive curves of each first casting simulation unit is in the same form as the material data required for subsequent body-in-white simulation. However, when performing body-in-white simulation on the overall body-in-white formed by connecting each body part, the mesh division method adopted is different from that in casting simulation, so that the set of material constitutive curves of each first casting simulation unit generated in step S102 cannot be directly provided for body-in-white simulation. To solve this problem, the following step S103 is executed.

[0070] Step S103: Based on the set of material constitutive curves of each first casting simulation unit, map to obtain the set of material constitutive curves of each body-in-white simulation unit for performing body-in-white simulation calculations.

[0071] Among them, each body-in-white simulation unit constitutes the body-in-white to be simulated.

[0072] In this embodiment, by using the mechanical property prediction results at a specified strain rate obtained from the casting simulation of body parts, the material constitutive curve groups of each first casting simulation unit of each body part involved in the body to be simulated are determined, which reflect the mechanical properties of each body part at different positions under different strain rates. Based on this, the material constitutive curve groups of each body simulation unit constituting the body to be simulated are mapped, providing detailed data support for subsequent body simulation calculations and improving the accuracy of body simulation by means of differential material property parameters that match the actual situation.

[0073] In addition, since casting defects will deteriorate the part performance, such as making the part brittle, reducing the strength, and decreasing the toughness, etc., and the defect situation of the casting can be reflected by the mechanical property parameters of the casting, that is, the mechanical property prediction data obtained through casting simulation can reflect the defect situation of the body part to a certain extent. This enables the body simulation scheme provided in this embodiment to utilize the defect data obtained from the casting stage through the material constitutive curve groups of each body simulation unit, taking into account the influence of part defects on body simulation, and thereby improving the accuracy of body simulation.

[0074] In one or more embodiments provided in the present application, the above step S101, obtaining the casting simulation data matching the mechanical test results of each body part, may include: performing the following steps A1 - A4 for each body part related to the body to be simulated:

[0075] Step A1, configuring the casting simulation parameters of the current body part.

[0076] Step A2, performing a casting simulation on the current body part to predict the mechanical properties of the current body part.

[0077] Exemplarily, the casting simulation performed when predicting the mechanical properties of a body part may include: casting filling simulation and casting solidification simulation. In addition, the above casting simulation task can be implemented based on die casting mold flow analysis software.

[0078] Step A3, determining whether the predicted casting simulation data of the current body part matches the mechanical test results of the current body part. If so, perform Step A4; otherwise, return to perform Step A1.

[0079] Step A4, outputting the casting simulation data of the current body part.

[0080] Based on the above content, a connection is established between independent casting simulation and body simulation, realizing an integrated chain simulation task for casting and body; and data transmission between casting simulation and body simulation is realized through steps S102 - S103, providing data support for achieving a high - accuracy body simulation task.

[0081] Exemplarily,Figures 3 - 5 respectively show a schematic diagram of the uniaxial tensile strength distribution, a schematic diagram of the yield strength distribution, and a schematic diagram of the elongation distribution of a vehicle body to be simulated, where the numerical values of the mechanical property prediction results of the vehicle body to be simulated at different positions are shown in different colors. As Figures 3 - 5 shown, there are significant differences in the numerical values at different vehicle body positions, and the material types of the first casting simulation units related to the vehicle body to be simulated may be as high as several million. Based on this, if the mechanical property prediction results are directly used as mechanical property data, it may lead to a large data processing pressure in subsequent generation of material constitutive curve groups and mesh parameter mapping; in addition, the simulation software relied on for vehicle body simulation may not be able to accommodate data at the million level.

[0082] To solve the above problems, in one or more embodiments provided in the present application, the above step S102, determining the mechanical property data of each first casting simulation unit according to the obtained casting simulation data, may include:

[0083] Step B: Using the mechanical property prediction data of each first casting simulation unit in the obtained casting simulation data as data objects to be clustered, and performing clustering processing.

[0084] Exemplarily, the data object corresponding to a certain first casting simulation unit (denoted as unit i) can be expressed as {σ b_i , σ s_i , δ i}, where σ b_i represents the predicted value of the uniaxial tensile strength of unit i, σ s_i represents the predicted value of the yield strength of unit i, and δ i represents the predicted value of the elongation of unit i. The data objects corresponding to each first casting simulation unit constitute a data space.

[0085] Step C: Determining the mechanical property data of each first casting simulation unit.

[0086] Specifically, the mechanical property data of each first casting simulation unit is the mechanical property data of the clustering center to which the current first casting simulation unit belongs, and the mechanical property data of each clustering center is determined according to the data objects constituting the cluster where the current clustering center is located.

[0087] Based on the above content, in this embodiment, the number of material types is reduced through clustering processing, the data processing pressure and calculation complexity in the process of configuring material attribute data for vehicle body simulation are reduced, and the complexity of the import parameters for vehicle body simulation is reduced, which helps to improve the efficiency of vehicle body simulation.

[0088] Optionally, the mechanical property data of each clustering center is the mean value of the data objects constituting the cluster where the current clustering center is located.

[0089] Taking K-means clustering as an example, the clustering process will be illustrated below. The above-mentioned clustering process may include the following steps B1-B5:

[0090] Step B1: Randomly select K data objects from the data space as the initial clustering centers.

[0091] Among them, K represents the number of clusters (or clusters) specified by the K-means clustering algorithm adopted. Each selected data object represents a clustering center.

[0092] Step B2: Calculate the distances (such as Euclidean distance) between each data object in the data space and each clustering center respectively, determine the cluster to which each data object belongs according to the nearest distance principle, and calculate the objective function value.

[0093] Specifically, the cluster to which any data object belongs is the cluster to which the clustering center closest to the current data object belongs. The objective function of K-means may refer to: minimizing the sum of the squares of the distances from each data object to the corresponding clustering center, and the calculated objective function value is the sum of the squares of the distances from each data object to the corresponding clustering center.

[0094] Step B3: Update the clustering centers based on the clustering results of Step B2 and calculate the new objective function value.

[0095] Exemplarily, for each of the K clusters, calculate the data means corresponding to the data objects belonging to the current cluster, specifically including the mean of the uniaxial tensile strength, the mean of the yield strength, and the mean of the elongation rate, and then use the calculated means as the new clustering centers of the current cluster to achieve the update of the clustering centers of the current cluster. Correspondingly, the clustering centers of the current cluster used in Step B2 can be called the previous clustering centers of the current cluster. Optionally, the clustering centers can also be updated based on other characteristic values corresponding to each data object, and the specific update method is not limited in this application.

[0096] Step B4: Determine whether the re-clustering condition is satisfied. If so, return to execute Step B2 based on the updated clustering centers, otherwise execute Step B5.

[0097] Among them, the re-clustering conditions include: the value change of the objective function (that is, the objective function value calculated in Step B2 is inconsistent with the new objective function value calculated in Step B3, or the difference degree between the two exceeds the preset first difference threshold), or, the clustering centers of at least one of the K clusters change (that is, the new clustering center is inconsistent with the previous clustering center, or the difference degree between the two exceeds the preset second difference threshold).

[0098] Step B5: Output the current clustering centers and the classification situation of the data objects as the clustering processing results.

[0099] Combined Figures 3 - 5 As shown, the predicted results of the mechanical properties of the body parts generally tend to be relatively concentrated within a relatively narrow parameter range. Based on this, when using K-means for clustering, the defect of poor clustering effect caused by noise can be avoided to a certain extent, that is, K-means clustering can be applied to achieve the clustering task required by this application.

[0100] Optionally, the value range of the above parameter K can be in the range of dozens to hundreds of magnitudes, and the specific value of K can be set according to the actual situation. In addition, other clustering algorithms can also be adopted during the clustering process, and this application does not limit this.

[0101] In one or more embodiments provided by this application, the above step S102, generating the material constitutive curve groups of each first casting simulation unit, may include: performing the following steps D1-D2 on each first casting simulation unit:

[0102] Step D1, determining the geometric transformation method.

[0103] Among them, the above geometric transformation method satisfies: the curve obtained by performing geometric transformation on the specified reference curve according to the geometric transformation method matches the mechanical property data of the current first casting simulation unit, and the specified reference curve is the material constitutive curve corresponding to the specified strain rate in the reference material constitutive curve group. It should be noted that the reference material constitutive curve group can be obtained by experimental testing of the body parts, and the test standard corresponding to the reference material constitutive curve group matches the test standard of the above mechanical test results, that is, the first test standard described above. Accordingly, it can be ensured that the material constitutive curve group expanded from the mechanical property data tends to be consistent with the actual material properties, thereby ensuring the accuracy and reliability of the material property data.

[0104] In addition, the above geometric transformation method may specifically include transformation methods such as stretching, scaling, and translation.

[0105] Step D2, performing geometric transformation on each curve in the reference material constitutive curve group according to the geometric transformation method to obtain the material constitutive curve group of the current first casting simulation unit.

[0106] Based on the specified reference curve in the constitutive curve group of the reference material, the geometric transformation method is determined, and then the constitutive curve group of the reference material is transformed accordingly to generate a constitutive relation curve group that meets the current mechanical property results, realizing the task of curve rewriting based on mechanical property data and providing a basis for meeting the data requirements of vehicle body simulation. Moreover, in this embodiment, by using the same geometric transformation method to transform each curve in a curve group, the direct relative relationship between the curves in the same group is ensured.

[0107] In one or more embodiments provided by the present application, the above step S103, mapping the material constitutive curve groups of the respective first casting simulation units to obtain the material constitutive curve groups of the respective vehicle body simulation units, may include the following steps E-F:

[0108] Step E: Determine the data storage nodes of the material constitutive curve groups of the respective first casting simulation units as the first nodes, and form a first node set from the respective first nodes.

[0109] It should be noted that when implementing simulation tasks for different purposes, different grid forms of simulation units are adopted, and the data storage nodes are also different. Exemplarily, the grid form of the first casting simulation unit may be a hexahedron; the data storage node of the hexahedron unit may be the center point, that is, the data of a hexahedron unit specifically refers to the data at the center point of the hexahedron.

[0110] Step F: Execute the following steps F1-F3 for each vehicle body simulation unit:

[0111] Step F1: Determine the data storage node of the current vehicle body simulation unit as the second node.

[0112] Exemplarily, the grid form of the vehicle body simulation unit may be a shell; the data storage node of the shell unit grid may be the shell center, that is, the data of a shell unit grid specifically may refer to the data at the shell center.

[0113] Step F2: Determine n1 first nodes around the second node from the first node set.

[0114] Wherein, the n1 is a preset positive integer. In a possible implementation, indexing may be performed based on the position of the second node, that is, multi-dimensional space search is performed. Exemplarily, a kd-tree (abbreviation for k-dimensional tree) may be used for spatial retrieval to ensure the calculation efficiency.

[0115] Step F3: Perform interpolation calculation on the material constitutive curve groups of the determined n1 first nodes to obtain the material constitutive curve group of the current vehicle body simulation unit.

[0116] Exemplarily, the above interpolation calculation may adopt a linear interpolation method. The present application does not limit the value of n1, the method for determining n1 first nodes, or the interpolation calculation method, which can be set according to actual requirements.

[0117] In this embodiment, the data of the casting simulation unit is mapped to the body simulation unit through grid interpolation, realizing the task of transmitting mechanical property data between different unit forms.

[0118] In one or more embodiments provided by the present application, the casting simulation data of each body part may further include: the predicted data of the casting residual stress of each second casting simulation unit constituting the current part.

[0119] Among them, the predicted data of the casting residual stress is obtained through casting deformation simulation, and this simulation can be carried out after the casting solidification simulation. It should be noted that the basis for the carried out casting deformation simulation can be the casting solidification simulation that obtains the above mechanical test results. That is to say, both the mechanical property prediction data and the predicted data of the casting residual stress constituting the casting simulation data are data after correction and match the test results.

[0120] On the above basis, the body simulation method provided by the embodiments of the present application may further include step S104:

[0121] Step S104: Map the predicted data of the casting residual stress of each second casting simulation unit to obtain the casting residual stress data of each body simulation unit for performing the body simulation calculation.

[0122] Among them, the second casting simulation unit may refer to the grid unit used when predicting the casting residual stress based on the body part.

[0123] Based on the above solution, the residual stress data of the body part obtained by casting simulation provides further data support for body simulation.

[0124] Optionally, each casting simulation parameter involved in the present application may be obtained through casting simulation. Based on this, Figure 6 shows a schematic flow chart of an integrated casting-body chain simulation. Combining Figure 6As shown in the figure, during the casting simulation stage of vehicle body parts, the casting filling simulation, casting solidification simulation, and casting deformation simulation can be successively performed on the vehicle body parts to be simulated. Through the casting solidification simulation, the mechanical property prediction data is obtained, specifically including uniaxial tensile strength, yield strength, and elongation data. Through the casting deformation simulation, the casting residual stress prediction data is obtained. The mechanical property prediction data and the casting residual stress prediction data together constitute the casting simulation data of the vehicle body parts to be simulated. On this basis, data correction is performed based on the mechanical test results of the vehicle body parts. If the predicted casting simulation data does not match the mechanical test results, the casting simulation parameters are adjusted and the casting simulation is performed again until the casting simulation data that matches the mechanical test results is obtained. Then, it enters the data transmission and processing stage. In this stage, the mechanical property prediction data of each vehicle body part obtained is successively subjected to clustering and dimensionality reduction processing (to obtain the mechanical property data of each casting simulation unit), curve rewriting processing (to obtain the material constitutive curve group of each casting simulation unit), and grid interpolation processing (to obtain the material constitutive curve group of each vehicle body simulation unit) to obtain the material property data required for vehicle body simulation. Specifically, during the curve rewriting processing, the reference material constitutive curve group is used, and this curve group can be derived from the casting stress-strain curve data obtained through testing. During the grid interpolation processing, the casting body grid file is used to indicate each vehicle body simulation unit. In addition, during the data transmission and processing stage, grid interpolation processing is also performed on the casting residual stress prediction data of each vehicle body part obtained to obtain the residual stress data required for vehicle body simulation. In addition, it should be noted that the above casting simulation tasks can be implemented based on casting simulation software (such as Zhizhu Supercloud Software). In a possible implementation, each step in the data transmission and processing stage can be integrated into the casting simulation software to further process the data output by the casting simulation module for output through the output port. Finally, it enters the vehicle body simulation stage to perform vehicle body simulation calculations. It should be noted that since vehicle body simulation and casting simulation are usually implemented based on different software, to ensure data compatibility, such as data format compatibility, before importing the output data of the data transmission and processing stage into vehicle body simulation software (such as vehicle body collision simulation software LS-Dyna, Abaqus, etc.), commercial software can be used for secondary development of the data import interface, and then the processed data is imported into the vehicle body simulation software, finally realizing the chain simulation process of integrated casting and vehicle body.

[0125] Based on the above, first, the filling, solidification, and deformation simulations of the body parts are carried out, and the mechanical property prediction results corrected by the mechanical test data (specifically including uniaxial tensile strength, yield strength, and elongation) and the casting residual stress prediction results are obtained. On this basis, grid interpolation processing is performed on the casting residual stress prediction results, and clustering and dimensionality reduction processing are performed on the mechanical property prediction results to significantly reduce the material types. Then, the mechanical results are rewritten in curves to meet the needs of body simulation. Finally, grid interpolation processing is performed for body simulation calculation.

[0126] In one or more embodiments provided by the present application, the above step S104, mapping the casting residual stress prediction data of each second casting simulation unit to obtain the casting residual stress data of each body simulation unit, may include the following steps G - H:

[0127] Step G: Determine the data storage nodes of the casting residual stress prediction data of each second casting simulation unit as the third nodes, and form a third node set from each third node.

[0128] Exemplarily, the grid form of the second casting simulation unit may be a tetrahedron; the data storage nodes of the tetrahedron unit may be vertices, that is, the data of a tetrahedron unit specifically refers to the data at the vertices of the tetrahedron.

[0129] Step H: Execute the following steps H1 - H3 for each body simulation unit:

[0130] Step H1: Determine the data storage node of the current body simulation unit as the second node.

[0131] Step H2: Determine n2 third nodes around the second node from the third node set.

[0132] Wherein, the n2 is a preset positive integer.

[0133] Step H3: Perform interpolation calculation on the casting residual stress prediction data of the determined n2 third nodes to obtain the casting residual stress data of the current body simulation unit.

[0134] It should be noted that the present application does not limit the value of n2, the method of determining n2 third nodes, and the method of interpolation calculation, which can be set according to actual needs. In addition, the interpolation process of the residual stress data is similar to that of the mechanical data (such as the material constitutive curve group), and can be referred to correspondingly.

[0135] In this embodiment, the data of the casting simulation unit is mapped to the body simulation unit through grid interpolation, and the task of transmitting the residual stress data between different unit forms is realized.

[0136] The following takes n2 = 4 as an example to illustrate step S104. When step S104 is executed, the old mesh includes each third node, and the new mesh includes each second node. Step S104 is intended to map the residual stress data of the old mesh to the new mesh. Exemplarily, "element-node" tables, "node-coordinate (such as Cartesian coordinates)" tables, and "node-data" tables of the new mesh and the old mesh can be constructed. Among them, the element can be represented by an element identifier, and the node can be represented by a node identifier. The data value in the "node-data" table of the new mesh needs to be determined by mesh interpolation. On this basis, a node of the new mesh can be taken as the current node, and then the spatial coordinates of the current node can be indexed from the "node-coordinate" table according to the identifier of the current node. Next, the position of the current node in the old mesh is determined, and this position is represented by the third node identifier of the old mesh and the relative position relationship; optionally, 4 third nodes of the old mesh can be extracted, and the position relationship between the element formed by the 4 extracted third nodes and the current node is judged through the coordinates of the current node and the 4 extracted third nodes. After traversing all combinations of the third nodes, 4 third nodes related to the current node can be determined, which are denoted as reference nodes. Then the relative position relationship refers to the position relationship between the reference element formed by the reference nodes and the current node, which can specifically include: the current node is inside the reference element, the current node is at the junction of multiple elements, etc. Based on this, the weighting coefficient is determined by using the distance relationship between the current node and the reference nodes, and then the residual stress data of the current node is calculated.

[0137] The body simulation device provided by the embodiment of the present application will be described below. The body simulation device described below can be mutually corresponded and referred to with the body simulation method described above.

[0138] Figure 7 It is a schematic structural diagram of a body simulation device disclosed in an embodiment of the present application. As Figure 7 shown, the device may include:

[0139] A data acquisition unit 11, configured to acquire casting simulation data that matches the mechanical test results of each body part; each body part is a part related to the body to be simulated, and the casting simulation data of each body part includes the mechanical property prediction data of each first casting simulation unit that constitutes the current part at a specified strain rate, and the specified strain rate is the strain rate corresponding to the mechanical test result;

[0140] A data processing unit 12, configured to determine the mechanical property data of each first casting simulation unit according to the acquired casting simulation data, and generate a material constitutive curve group of each first casting simulation unit; the material constitutive curve corresponding to the specified strain rate in the material constitutive curve group of each first casting simulation unit matches the mechanical property data of the current first casting simulation unit;

[0141] The data processing unit 12 is further configured to map, according to the material constitutive curve groups of the first casting simulation units, material constitutive curve groups of the vehicle body simulation units for vehicle body simulation calculation; the vehicle body simulation units constitute the vehicle body to be simulated.

[0142] In one or more embodiments provided by the present application, the data acquisition unit 11 may include a casting simulation unit, which is configured to perform the following steps for each vehicle body part related to the vehicle body to be simulated:

[0143] Configure the casting simulation parameters of the current vehicle body part;

[0144] Perform casting simulation on the current vehicle body part to predict the mechanical properties of the current vehicle body part;

[0145] Determine whether the casting simulation data of the predicted current vehicle body part matches the mechanical test result of the current vehicle body part. If so, output the casting simulation data of the current vehicle body part; otherwise, return to the step of configuring the casting simulation parameters of the current vehicle body part.

[0146] In one or more embodiments provided by the present application, the process by which the data processing unit 12 determines the mechanical property data of the first casting simulation units based on the acquired casting simulation data may include:

[0147] Take the mechanical property prediction data of the first casting simulation units in the acquired casting simulation data as data objects to be clustered, and perform clustering processing;

[0148] Determine the mechanical property data of the first casting simulation units; the mechanical property data of each first casting simulation unit is the mechanical property data of the clustering center of the cluster to which the current first casting simulation unit belongs, and the mechanical property data of each clustering center is determined based on the data objects constituting the cluster where the current clustering center is located.

[0149] In one or more embodiments provided by the present application, the mechanical property data of each clustering center is the mean value of the data objects constituting the cluster where the current clustering center is located.

[0150] In one or more embodiments provided by the present application, the process by which the data processing unit 12 generates the material constitutive curve groups of the first casting simulation units may include performing the following steps for each first casting simulation unit:

[0151] Determine the geometric transformation method; the curve obtained by performing geometric transformation on the specified reference curve according to the geometric transformation method matches the mechanical property data of the current first casting simulation unit, and the specified reference curve is the material constitutive curve corresponding to the specified strain rate in the reference material constitutive curve group;

[0152] Perform geometric transformation on each curve in the reference material constitutive curve group according to the described geometric transformation method to obtain the material constitutive curve group of the current first casting simulation unit.

[0153] In one or more embodiments provided by the present application, the process of the data processing unit 12 mapping to obtain the material constitutive curve groups of each body simulation unit based on the material constitutive curve groups of the first casting simulation units may include:

[0154] Determine the data storage nodes of the material constitutive curve groups of the first casting simulation units as first nodes, and form a first node set from the first nodes;

[0155] Execute the following steps for each body simulation unit:

[0156] Determine the data storage node of the current body simulation unit as the second node;

[0157] Determine n1 first nodes around the second node from the first node set; where the n1 is a preset positive integer;

[0158] Perform interpolation calculation on the material constitutive curve groups of the determined n1 first nodes to obtain the material constitutive curve group of the current body simulation unit.

[0159] In one or more embodiments provided by the present application, the casting simulation data of each body part further includes: the predicted data of the casting residual stress of each second casting simulation unit constituting the current part, and the predicted data of the casting residual stress is obtained through casting deformation simulation.

[0160] On the above basis, the data processing unit 12 can also be used to: map to obtain the casting residual stress data of each body simulation unit based on the predicted data of the casting residual stress of each second casting simulation unit for performing the body simulation calculation.

[0161] In one or more embodiments provided by the present application, the process of the data processing unit 12 mapping to obtain the casting residual stress data of each body simulation unit based on the predicted data of the casting residual stress of each second casting simulation unit may include:

[0162] Determine the data storage nodes of the predicted data of the casting residual stress of the second casting simulation units as third nodes, and form a third node set from the third nodes;

[0163] Execute the following steps for each body simulation unit:

[0164] Determine the data storage node of the current body simulation unit as the second node;

[0165] Determine n2 third nodes around the second node from the third node set; where n2 is a preset positive integer;

[0166] Perform interpolation calculation on the predicted data of the casting residual stress of the determined n2 third nodes to obtain the casting residual stress data of the current vehicle body simulation unit.

[0167] The vehicle body simulation device provided by the embodiments of the present application can be applied to electronic devices, such as terminals with data processing capabilities: such as mobile phones, computers, servers, etc. Optionally, Figure 8 The hardware structure block diagram of the electronic device is shown. Refer to Figure 8 , the hardware structure of the electronic device may include: at least one processor 1, at least one communication interface 2, at least one memory 3, and at least one communication bus 4;

[0168] In the embodiments of the present application, the number of the processor 1, the communication interface 2, the memory 3, and the communication bus 4 is at least one, and the processor 1, the communication interface 2, and the memory 3 complete mutual communication through the communication bus 4;

[0169] The processor 1 may be a central processing unit CPU, or a specific integrated circuit ASIC (Application Specific Integrated Circuit), or one or more integrated circuits configured to implement the embodiments of the present invention, etc.;

[0170] The memory 3 may include a high-speed RAM memory, and may also include a non-volatile memory, etc., such as at least one disk memory;

[0171] Among them, the memory is used to store a computer program, and the processor is used to execute the computer program so that the electronic device can implement any of the above vehicle body simulation methods.

[0172] In the embodiments of the present application, a storage medium is further provided. The storage medium carries one or more computer programs. When the one or more computer programs are executed by an electronic device, the electronic device can be enabled to implement any of the vehicle body simulation methods provided by the embodiments of the present application.

[0173] In the embodiments of the present application, a computer program product is further provided, including computer-readable instructions. When the computer-readable instructions run on an electronic device, the electronic device can be enabled to implement any of the vehicle body simulation methods provided by the embodiments of the present application.

[0174] Finally, it should also be noted that in this text, relational terms such as first and second are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any actual relationship or order between these entities or operations. Moreover, the term "comprising", "including" or any other variant thereof is intended to cover non-exclusive inclusion, such that a process, method, article or device comprising a series of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such process, method, article or device. Without further limitation, an element defined by the statement "comprising an..." does not exclude the presence of additional identical elements in the process, method, article or device comprising said element.

[0175] The various embodiments in this specification are described in a progressive manner, with each embodiment focusing on the differences from other embodiments. The embodiments can be combined as needed, and the same or similar parts can be referred to each other.

[0176] The above description of the disclosed embodiments enables those skilled in the art to implement or use the present application. Various modifications to these embodiments will be obvious to those skilled in the art, and the general principles defined herein can be implemented in other embodiments without departing from the spirit or scope of the present application. Therefore, the present application will not be limited to these embodiments shown herein, but will be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A vehicle body simulation method, characterized in that, Including: Obtaining casting simulation data that matches the mechanical test results of each vehicle body part; each of the vehicle body parts is a part related to the vehicle body to be simulated, and the casting simulation data of each vehicle body part includes the mechanical property prediction data of each first casting simulation unit that makes up the current part at a specified strain rate, and the specified strain rate is the strain rate corresponding to the mechanical test result; Determining the mechanical property data of each first casting simulation unit based on the obtained casting simulation data, and generating a material constitutive curve group for each first casting simulation unit; The material constitutive curve corresponding to the specified strain rate in the material constitutive curve group of each first casting simulation unit matches the mechanical property data of the current first casting simulation unit; Mapping to obtain a material constitutive curve group for each vehicle body simulation unit based on the material constitutive curve groups of the first casting simulation units for performing vehicle body simulation calculations; the vehicle body simulation units constitute the vehicle body to be simulated; Wherein, the generating of the material constitutive curve group for each first casting simulation unit includes: performing the following steps on each first casting simulation unit: Determining a geometric transformation method; the curve obtained by geometrically transforming a specified reference curve according to the geometric transformation method matches the mechanical property data of the current first casting simulation unit, and the specified reference curve is the material constitutive curve corresponding to the specified strain rate in the reference material constitutive curve group; Performing geometric transformation on each curve in the reference material constitutive curve group according to the geometric transformation method to obtain the material constitutive curve group of the current first casting simulation unit.

2. The vehicle body simulation method according to claim 1, characterized in that, The determining of the mechanical property data of each first casting simulation unit based on the obtained casting simulation data includes: Taking the mechanical property prediction data of each first casting simulation unit in the obtained casting simulation data as data objects to be clustered, and performing clustering processing; Determining the mechanical property data of each first casting simulation unit; the mechanical property data of each first casting simulation unit is the mechanical property data of the clustering center to which the current first casting simulation unit belongs, and the mechanical property data of each clustering center is determined based on the data objects that make up the cluster where the current clustering center is located.

3. The vehicle body simulation method according to claim 2, wherein, The mechanical property data of each clustering center is the mean value of the data objects that make up the cluster where the current clustering center is located.

4. The vehicle body simulation method according to claim 1, characterized in that The mapping to obtain a material constitutive curve group for each vehicle body simulation unit based on the material constitutive curve groups of the first casting simulation units includes: Determining the data storage nodes of the material constitutive curve groups of the first casting simulation units as first nodes, and forming a first node set by the first nodes; Performing the following steps on each vehicle body simulation unit: Determining the data storage node of the current vehicle body simulation unit as a second node; Determining n1 first nodes around the second node from the first node set; where n1 is a preset positive integer; Performing interpolation calculation on the material constitutive curve groups of the determined n1 first nodes to obtain the material constitutive curve group of the current vehicle body simulation unit.

5. The vehicle body simulation method according to any one of claims 1-3, characterized in that, The casting simulation data of each vehicle body part further includes: the predicted data of the casting residual stress of each second casting simulation unit that constitutes the current part, and the predicted data of the casting residual stress is obtained through casting deformation simulation; this method further includes: Based on the predicted data of the casting residual stress of each second casting simulation unit, mapping to obtain the casting residual stress data of each vehicle body simulation unit for performing the vehicle body simulation calculation.

6. The vehicle body simulation method according to claim 5, wherein The mapping to obtain the casting residual stress data of each vehicle body simulation unit based on the predicted data of the casting residual stress of each second casting simulation unit includes: Determine the data storage nodes of the predicted data of the casting residual stress of each second casting simulation unit as the third nodes, and form a third node set by each third node; Perform the following steps for each vehicle body simulation unit: Determine the data storage node of the current vehicle body simulation unit as the second node; Determine n2 third nodes around the second node from the third node set; where n2 is a preset positive integer; Perform interpolation calculation on the predicted data of the casting residual stress of the determined n2 third nodes to obtain the casting residual stress data of the current vehicle body simulation unit.

7. A vehicle body simulation device, characterized in that, Include: A data acquisition unit for acquiring casting simulation data that matches the mechanical test results of each vehicle body part; each vehicle body part is a part related to the vehicle body to be simulated, and the casting simulation data of each vehicle body part includes the predicted mechanical property data of each first casting simulation unit that constitutes the current part at a specified strain rate, and the specified strain rate is the strain rate corresponding to the mechanical test result; A data processing unit for determining the mechanical property data of each first casting simulation unit based on the acquired casting simulation data and generating a material constitutive curve group for each first casting simulation unit; The material constitutive curve corresponding to the specified strain rate in the material constitutive curve group of each first casting simulation unit matches the mechanical property data of the current first casting simulation unit; The data processing unit is further configured to map to obtain a material constitutive curve group for each vehicle body simulation unit based on the material constitutive curve groups of each first casting simulation unit for performing vehicle body simulation calculation; each vehicle body simulation unit constitutes the vehicle body to be simulated; Among them, the process of the data processing unit generating the material constitutive curve group for each first casting simulation unit includes: performing the following steps for each first casting simulation unit: Determine the geometric transformation method; the curve obtained by performing geometric transformation on the specified reference curve according to the geometric transformation method matches the mechanical property data of the current first casting simulation unit, and the specified reference curve is the material constitutive curve corresponding to the specified strain rate in the reference material constitutive curve group; Perform geometric transformation on each curve in the reference material constitutive curve group according to the geometric transformation method to obtain the material constitutive curve group of the current first casting simulation unit.

8. An electronic device, characterized in that, Includes at least one processor and a memory connected to the processor, where: The memory is used to store computer programs; The processor is used to execute the computer program so that the electronic device can implement the vehicle body simulation method according to any one of claims 1 to 6.

9. A computer program product, characterized in that, It includes computer-readable instructions that, when running on an electronic device, enable the electronic device to implement the vehicle body simulation method according to any one of claims 1 to 6.

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