Methods and equipment for locating, separating, and integrating automotive components.
Patent Information
- Authority / Receiving Office
- TH · TH
- Patent Type
- Applications
- Current Assignee / Owner
- JFE STEEL CORP
- Filing Date
- 2021-10-01
- Publication Date
- 2025-11-24
AI Technical Summary
Existing methods for determining division positions and integration of vehicle body parts fail to efficiently and sufficiently improve vehicle performance, as they often result in deteriorated performance of adjacent parts despite improvements in some areas, due to fixed dividing positions and inadequate optimization of plate thickness and material properties.
A method and device that use sensitivity analysis to determine optimal division and integration positions of vehicle body parts by calculating the material density of each element, allowing for dynamic adjustment of plate thickness and material properties based on sensitivity, thereby improving vehicle body performance.
This approach enables efficient and substantial enhancement of vehicle body performance by accurately identifying high and low sensitivity regions, allowing for targeted adjustments that improve rigidity and reduce weight, while maintaining overall performance and minimizing manufacturing costs.
Smart Images
Figure 00000003_0000 
Figure 00000004_0000 
Figure 00000005_0000
Abstract
Description
Method and device for determining division position and integration of vehicle body parts
[0001] The present invention relates to a method and device for determining the dividing positions and integration of automotive body parts, which review and optimize the dividing positions of automotive body parts for an automotive body consisting of a plurality of automotive parts and which has predetermined joining points at which the body parts are joined as a parts assembly, and in particular to a method and device for determining the dividing positions and integration of automotive body parts, which can efficiently improve the performance of the vehicle body of an automobile or the like.
[0002] In recent years, the automotive industry has been promoting weight reduction of vehicle bodies due to environmental issues, and CAE (computer-aided engineering) analysis has become an essential technology for vehicle body design. CAE analysis includes stiffness analysis, crashworthiness analysis, and vibration analysis, and contributes greatly to improving vehicle body performance.
[0003] It is also known that CAE analysis is not limited to simple performance evaluation, but can also improve various vehicle body performances and reduce weight by using optimization analysis techniques such as mathematical optimization, size optimization, shape optimization, and topology optimization. As an example of such optimization analysis techniques, Patent Document 1 discloses a method for topology optimization of components of a complex structural body.
[0004] Furthermore, Patent Document 2 discloses a method for performing a sensitivity analysis of vehicle body parts with respect to vehicle body performance using optimization analysis technology, and for identifying vehicle body parts for which measures should be taken to improve vehicle body performance based on the results of the sensitivity analysis.
[0005] JP 2010-250818 A JP 2020-60820 A
[0006] The method disclosed in Patent Document 2 involves modeling vehicle body parts, calculating the sensitivity of each element used in the model to vehicle body performance through sensitivity analysis, determining the sensitivity for each vehicle body part based on the calculated sensitivity of each element, and clarifying the vehicle body parts that should be subject to measures such as changing the plate thickness or material properties.
[0007] In this method, the dividing positions of the body parts are given and fixed in advance, and even if there is a distribution of sensitivity within the same body part, the level of sensitivity is determined for each body part, so the plate thickness and material properties of the body part that is determined to require countermeasures are changed. Therefore, even if it is determined that the plate thickness, etc. of a body part should be changed, there may be parts within the body part where the plate thickness, etc. should not be changed, and because the dividing positions are fixed, there are cases in which changing the plate thickness, etc. of the body part does not sufficiently improve the vehicle performance.
[0008] Therefore, it is believed that by changing the position at which the vehicle body is divided into multiple body parts and appropriately setting the plate thickness and material properties for each of the newly divided or integrated body parts as a result of the change, it is possible to efficiently improve vehicle body performance.
[0009] One method for determining whether to separate or integrate body parts is based on the stress and strain generated by the load applied to the body parts. In this method, the boundary between areas of the body part with high and low stress is determined as the separation position, and body parts with similar stresses can be integrated.
[0010] However, even if this method is used to change the dividing position or the thickness of the body parts to be integrated, the performance of the body part in question may improve, but the performance of adjacent body parts may decrease, and there is no guarantee that the performance of the entire body will improve, so it has not been possible to efficiently and sufficiently improve body performance.
[0011] The present invention has been made in consideration of the above-mentioned problems, and its object is to provide a method and apparatus for determining the division positions and integration of vehicle body parts, which can efficiently and sufficiently improve vehicle body performance.
[0012] The method for determining the division positions and integration of vehicle body parts according to the present invention involves a computer performing the following steps for an automotive body model having a plurality of vehicle body parts to determine the division positions of the vehicle body parts and / or the vehicle body parts to be integrated, and includes an automotive body model acquisition step of acquiring the vehicle body model having the plurality of vehicle body parts modeled with a plurality of elements and joining points at which the plurality of vehicle body parts are joined as a component assembly; a sensitivity analysis step of setting objectives related to the vehicle performance of the vehicle body model, constraints related to the volume of the vehicle body model, and only loading and constraint conditions or loading conditions to be imposed on the vehicle body model, and determining the sensitivity of each of the elements in each of the vehicle body parts that satisfy the objective conditions under only the loading and constraint conditions or loading conditions and the constraint conditions; and a vehicle part division position / integration determination step of determining the positions at which the vehicle body parts will be divided and / or the vehicle body parts to be integrated based on the sensitivity of each of the elements in each of the vehicle body parts.
[0013] The sensitivity analysis step may calculate element densities of the elements that satisfy the target conditions, and use the calculated element densities as the sensitivities of the elements.
[0014] The vehicle body model acquisition step may set, in addition to the joint points, all additional joint points at which the component assemblies can be joined to the acquired vehicle body model.
[0015] The device for determining the division positions and integration of body parts of the present invention determines the division positions of the body parts and / or the body parts to be integrated for a body model having a plurality of body parts, and includes a body model acquisition unit that acquires the body model having the plurality of body parts modeled with a plurality of elements and joining points at which the plurality of body parts are joined as a part assembly, a sensitivity analysis unit that sets target conditions related to the body performance of the body model and constraint conditions related to the volume of the body model, and load / constraint conditions or load conditions only to be applied to the body model, and determines the sensitivity of each element in each body part that satisfies the target conditions under only the load / constraint conditions or load conditions and the constraint conditions, and a body part division position / integration determination unit that determines the positions at which the body parts will be divided and / or the body parts to be integrated based on the sensitivity of each element in each body part, in accordance with the operator's instructions.
[0016] The sensitivity analysis unit may calculate a material density of each of the elements in each of the vehicle body parts that satisfies the target condition, and may use the calculated material density as the sensitivity of each of the elements.
[0017] The vehicle body model acquisition unit may set, in addition to the joint points, all additional joint points at which the component assemblies can be joined to the acquired vehicle body model.
[0018] According to the present invention, the sensitivity to vehicle body performance is calculated for each element used to model the vehicle body part, and based on the calculated sensitivity of each element in the vehicle body part, the division positions of the predetermined vehicle body parts can be reviewed to determine the optimal division positions of the vehicle body parts and the vehicle body parts to be integrated.By appropriately changing the plate thickness and material properties for each new vehicle body part obtained by division or integration, vehicle body performance can be improved efficiently and sufficiently.
[0019] FIG. 1 is a block diagram of a division / integration determination device for determining division positions and integration of vehicle body parts according to an embodiment of the present invention. FIG. 2 is a diagram showing a vehicle body model to be analyzed in the embodiment of the present invention. FIG. 3 is a diagram showing joint points in the vehicle body model to be analyzed and all additional joint points that can be joined ((a) preset joint points, (b) all additional joint points that can be joined). FIG. 4 is a diagram showing an example of load / constraint conditions applied to the vehicle body model in the embodiment of the present invention. FIG. 5 is a diagram showing an example of determining division positions and integration of the vehicle body part based on the results of a sensitivity analysis of a vehicle body part (A-pillar) on the front side of the vehicle body model and the material density determined as a sensitivity by the sensitivity analysis ((a) front side view of the original vehicle body model given in advance, (b) material density determined by the sensitivity analysis, (c) front side view of the vehicle body model after division and integration). 6A and 6B are diagrams showing an example in which the division positions and integration of the vehicle body parts are determined based on the results of sensitivity analysis of the vehicle body parts on the rear side of the vehicle body model and the material density calculated as the sensitivity by the sensitivity analysis in an embodiment of the present invention ((a) a top view of the rear side of the original vehicle body model given in advance, (b) the material density calculated by the sensitivity analysis, and (c) a top view of the rear side of the vehicle body model after division and integration). Fig. 7A and 7B are diagrams showing an example in which the division positions and integration of the vehicle body parts are determined based on the results of sensitivity analysis of the vehicle body part (side sill outer) on the left side of the vehicle body model and the material density calculated as the sensitivity by the sensitivity analysis in an embodiment of the present invention ((a) a perspective view of the left side of the original vehicle body model given in advance, (b) the material density calculated by the sensitivity analysis, and (c) a perspective view of the left side of the vehicle body model after division and integration). 8A and 8B are diagrams showing an example of a divided and integrated vehicle body model in which the division positions and integration of vehicle body parts have been determined in an embodiment of the present invention ((a) a pre-given original vehicle body model, (b) a divided and integrated vehicle body model after division and integration). Fig. 9 is a flow chart showing the processing flow of a method for determining the division positions and integration of vehicle body parts according to an embodiment of the present invention.10 is a diagram showing an example of determining the division positions and integration of vehicle body parts based on the results of sensitivity analysis of vehicle body parts on the front side of a vehicle body model and the material density calculated as the sensitivity by the sensitivity analysis in another aspect of the embodiment of the present invention ((a) a side view of the front side of the original vehicle body model given in advance, (b) the material density calculated by the sensitivity analysis, (c) a side view of the front side of the vehicle body model after division and integration). FIG. 11 is a diagram showing an example of determining the division positions and integration of vehicle body parts based on the results of sensitivity analysis of vehicle body parts on the rear side of a vehicle body model and the material density calculated as the sensitivity by the sensitivity analysis in another aspect of the embodiment of the present invention ((a) a top view of the rear side of the original vehicle body model given in advance, (b) the material density calculated by the sensitivity analysis, (c) a top view of the rear side of the vehicle body model after division and integration). 12 is a diagram showing an example in which the division positions and integration of vehicle body parts are determined based on the results of sensitivity analysis of vehicle body parts on the left side of the vehicle body model and the material density determined as the sensitivity by the sensitivity analysis in another aspect of the embodiment of the present invention ((a) a perspective view of the left side of the original vehicle body model given in advance, (b) the material density determined by the sensitivity analysis, and (c) a perspective view of the left side of the vehicle body model after division and integration). FIG. 13 is a diagram showing an example of a divided and integrated vehicle body model in which the division positions and integration of vehicle body parts are determined in another aspect of the embodiment of the present invention ((a) the original vehicle body model given in advance, (b) the divided and integrated vehicle body model after division and integration).
[0020] Before describing the embodiments of the present invention, a vehicle body model to which the present invention is applied will be described.
[0021] <Vehicle Body Model> The vehicle body model 100 of the present invention includes a plurality of vehicle body parts, as shown in Fig. 2 as an example. The vehicle body parts include body frame parts such as an A-pillar lower 101, an A-pillar upper 103, a rear roof rail center 105, a rear roof rail side 107, a compartment center A 109, a compartment side A 111, a compartment center B 113, a compartment side B 115, a side sill outer 117, and a wheel house reinforcement 119, as well as suspension parts (not shown). These vehicle body parts are modeled using a plurality of shell elements and / or solid elements.
[0022] Furthermore, in the vehicle body model 100, as shown in Fig. 3(a) as an example, joint points 121 for joining a plurality of vehicle body parts as a part assembly are set at predetermined intervals. Note that in the vehicle body model 100, the joint points 121 are set at intervals of 25 to 60 mm.
[0023] The material properties and element information of each body part that constitutes the body model 100, as well as information regarding the joint points 121 (Figure 2(a)) in each part assembly, are stored in the body model file 21 (see Figure 1) described later.
[0024] <Division / Integration Determining Device> The configuration of a division / integration determining device for determining division positions and integration of vehicle body parts according to an embodiment of the present invention will be described below.
[0025] A division / integration determination device 1 according to this embodiment determines division positions of a plurality of body parts and / or which body parts to integrate for a vehicle body model having the body parts. As shown in Fig. 1, the division / integration determination device 1 according to this embodiment is configured by a PC (personal computer) or the like, and has a display device 3, an input device 5, a memory storage 7, a working data memory 9, and an arithmetic processing unit 11. The display device 3, the input device 5, the memory storage 7, and the working data memory 9 are connected to the arithmetic processing unit 11, and each function is executed in response to a command from the arithmetic processing unit 11.
[0026] Below, we will explain each component of the division / integration determination device 1 of this embodiment when the vehicle body model 100 shown in Figures 2 and 3 is used as the analysis target and the division positions of the vehicle body parts that make up the vehicle body model 100 and the vehicle body parts to be integrated are determined.
[0027] <Display Device> The display device 3 is used to display the analysis results and is configured by a liquid crystal monitor or the like.
[0028] <<Input Device>> The input device 5 is used for issuing display instructions for the vehicle body model file 21 and inputting conditions by the operator, and is composed of a keyboard, a mouse, and the like.
[0029] <Storage Device> The storage device 7 is used to store various files such as a vehicle body model file 21 that records various information related to the vehicle body model, as will be described later, and is configured with a hard disk or the like.
[0030] <Working Data Memory> The working data memory 9 is used for temporary storage of data used by the arithmetic processing unit 11 and for calculations, and is composed of RAM (Random Access Memory) and the like.
[0031] <<Calculation Processing Unit>> As shown in Fig. 1, the calculation processing unit 11 has a vehicle body model acquisition unit 13, a sensitivity analysis unit 15, and a vehicle body part division position / integration determination unit 17, and is configured by a CPU (central processing unit) such as a PC. Each of these units functions when the CPU executes a predetermined program. The functions of each of the above units in the calculation processing unit 11 are described below.
[0032] (Vehicle body model acquisition unit) The vehicle body model acquisition unit 13 acquires a vehicle body model 100 that includes vehicle body parts (such as the A-pillar lower 101) modeled with multiple elements, as shown in Figures 2 and 3(a), and joining points 121 that join multiple vehicle body parts as a component assembly.
[0033] In this embodiment, each vehicle body part constituting vehicle body model 100 is assumed to be modeled using shell elements, as an example, and information on the shell elements constituting each vehicle body part and the material properties of each vehicle body part (Young's modulus, specific gravity, Poisson's ratio, etc.) is recorded in a vehicle body model file 21 (see FIG. 1 ) stored in storage device 7. Therefore, vehicle body model acquisition unit 13 can acquire vehicle body model 100 by reading vehicle body model file 21.
[0034] (Sensitivity analysis unit) The sensitivity analysis unit 15 sets target conditions related to the body performance of the body model 100, constraint conditions related to the volume of the body model 100, and load / constraint conditions or only load conditions to be applied to the body model 100, and calculates the sensitivity of each element in each body part that satisfies the target conditions under the set load / constraint conditions or only the load conditions and constraint conditions.
[0035] In this embodiment, the target conditions related to vehicle body performance set by the sensitivity analysis unit 15 include minimizing the total strain energy in the vehicle body model 100, minimizing displacement, minimizing stress, maximizing rigidity, etc., and these target conditions can be selected appropriately depending on the vehicle body performance to be targeted.
[0036] Furthermore, constraint conditions on the volume of the vehicle body model 100 set by the sensitivity analysis unit 15 include a volume fraction ratio that defines the volume of the vehicle body parts.
[0037] As the load and constraint conditions to be set on the vehicle body model 100 by the sensitivity analysis unit 15, for example, the load and constraint conditions shown in Fig. 4 are set. The load and constraint conditions shown in Fig. 4 are such that the mounting positions (P in the figure) of the left and right front suspensions of the vehicle body model 100 are set as load points, a vertically upward load is applied to one and a vertically downward load to the other, and further the mounting positions (Q in the figure) of the left and right rear subframes of the vehicle body model 100 are constrained.
[0038] Furthermore, in this embodiment, the sensitivity analysis unit 15 may use topology optimization to which a densimetry is applied to calculate the material density of each element in each vehicle body part as the sensitivity of the element. The calculated material density of each element corresponds to the density ρ shown in Equation (1).
[0039]
[0040] The normalized density ρ in equation (1) is a virtual density that represents the filling state of the material in each element, and takes a value between 0 and 1. In other words, if the material density ρ of an element is 1, the element is completely filled with material, if the material density ρ is 0, the element is not filled with material and is completely hollow, and if the material density of an element is an intermediate value between 0 and 1, the element is in an intermediate state that is neither solid nor hollow.
[0041] The material density calculated by topology optimization is close to 1 for elements that have a large contribution to vehicle body performance, indicating a high sensitivity to vehicle body performance. In contrast, the material density of elements that have a small contribution to vehicle body performance is close to 0, indicating a low sensitivity to vehicle body performance. In this way, the material density of each element calculated by topology optimization is an index that represents the sensitivity of each element to vehicle body performance.
[0042] 5(b), 6(b), and 7(b) show, as an example of the sensitivity of elements calculated by the sensitivity analysis unit 15, an example of the result of material density calculated for the elements of each vehicle body part when a static torsion is applied to the vehicle body model 100 under the load and constraint conditions shown in FIG. 4 (absolute value of the load applied to each load point is 1000 N) with the target condition being maximization of rigidity and the constraint condition being a volume constraint rate of 25%.
[0043] Here, Figure 5(b) is a side view of the A-pillar lower 101 and A-pillar upper 103 (Figure 5(a)) on the front side of the vehicle body model 100, Figure 6(b) is a top view of the rear side (Figure 6(a)) of the vehicle body model 100, and Figure 7(b) is a perspective view of the side sill outer 117 and wheel house reinforcement 119 (Figure 7(a)) on the left side of the vehicle body model 100.
[0044] As shown in Figures 5(b), 6(b), and 7(b), it can be seen that even within the same body part, there are areas that are highly sensitive to static torsion and areas that are less sensitive (for example, the outer side sill 117 shown in Figure 7(b)), and that there are also different body parts that have roughly the same level of sensitivity overall (for example, the lower A-pillar 101 and upper A-pillar 103 shown in Figure 5(b)).
[0045] The sensitivity analysis unit 15 may use an inertia relief method to set only a load condition that takes into account the inertia force when a dynamic load is applied to the car body model 100. The inertia relief method is an analytical technique that determines stress and strain from the force acting on an object in constant acceleration motion in a state where the object is supported (free support) at a support point that serves as the reference for the coordinates of the inertia force, and is used in static analysis of airplanes and ships in motion.
[0046] Furthermore, analysis software that performs optimization analysis such as topology optimization can be used to calculate the material density of the elements by the sensitivity analysis unit 15. In this case, each vehicle body part that constitutes the vehicle body model 100 is set as a design space, material density is assigned as a design variable to the elements that constitute the vehicle body part set as the design space, and predetermined target conditions, constraint conditions, and load / constraint conditions are set, thereby calculating the material density as the sensitivity of the element.
[0047] However, when the optimization analysis is performed in the sensitivity analysis unit 15, an optimization analysis method other than topology optimization may be applied.
[0048] (Body part division position / integration determination unit) The body part division position / integration determination unit 17 determines the positions at which to divide the body parts and / or the body parts to be integrated, based on the sensitivity of each element in the body parts determined by the sensitivity analysis unit 15, in accordance with the operator's instructions.
[0049] When determining the division positions of body parts and the body parts to be integrated based on sensitivity, the difference in sensitivity is used as an indicator, and based on the operator's instructions, the position where the difference in sensitivity is large in the same body part is determined as the division position, and adjacent body parts where the difference in sensitivity is small are determined to be integrated.
[0050] In this embodiment, a position where the difference in sensitivity of a body part is 0.7 or more is determined as a dividing position, and if the difference in sensitivity of adjacent body parts is 0.3 or less, they are determined to be integrated.
[0051] Then, the body part division position / integration determination unit 17 divides the body part at the division position for the body part for which the division position has been newly determined to create a new body part, and integrates multiple body parts that have been determined to be integrated into one body part.
[0052] The division positions of the body parts and the body parts to be integrated are determined based on the sensitivity of the elements of each body part shown in Figures 5(b), 6(b), and 7(b), and the results of dividing and integrating the body parts are shown in Figures 5(c), 6(c), and 7(c), respectively.
[0053] On the front side of the vehicle body model 100 (FIG. 5(a)), as shown in FIG. 5(b), the difference in sensitivity (material density) between the A-pillar lower 101 and the A-pillar upper 103 was small, at 0.3 or less (dashed ellipse in the figure).
[0054] Therefore, it is decided to integrate the A-pillar lower 101 and the A-pillar upper 103, forming an A-pillar 201 as shown in FIG. 5(c).
[0055] On the rear side of the vehicle body model 100 (FIG. 6(a)), as shown by the dashed ovals in FIG. 6(b), the difference in sensitivity between the rear roof rail center 105 and rear roof rail side 107, the compartment center A 109 and compartment side A 111, and the compartment center B 113 and compartment side B 115 was small, at 0.3 or less.
[0056] Therefore, it was decided to integrate the rear roof rail center 105 and rear roof rail side 107, the compartment center A 109 and compartment side A 111, and the compartment center B 113 and compartment side B 115, respectively, to form the rear roof rail 203, compartment A 205, and compartment B 207, as shown in Figure 6 (c).
[0057] On the left side of the vehicle body model 100 (Figure 7(a)), as shown by the dashed ellipse in Figure 7(b), the difference in sensitivity between the front and rear sides of approximately the center of the side sill outer 117 was large, at 0.7 or more, while the difference in sensitivity between the rear part of the side sill outer 117 and the wheel house reinforcement 119 was small, at 0.3 or less.
[0058] 7C, the dividing position is determined to be approximately the center of the side sill outer 117 where the difference in sensitivity is greatest, and the front side is divided into a side sill outer front 209. Furthermore, the rear side of the dividing position in the side sill outer 117 is determined to be integrated with the wheel house reinforcement 119, and is formed into a side sill outer rear 211.
[0059] FIG. 8(b) shows an overall view of the divided and integrated vehicle body model 200 after the division positions and integration of the vehicle body parts have been determined based on the sensitivities shown in FIGS. 5(b), 6(b), and 7(b).
[0060] In this embodiment, the position where the difference in sensitivity of a body part is 0.7 or more is determined to be the dividing position, and adjacent body parts where the difference in sensitivity is 0.3 or less are determined to be integrated, but the difference in sensitivity that determines the dividing position or integration may be selected appropriately.
[0061] <Method of Determining Dividing Positions and Integration of Vehicle Body Parts> Next, a method of determining dividing positions and integration of vehicle body parts according to this embodiment will be described below.
[0062] In the method for determining the division positions and integration of vehicle body parts according to this embodiment, a computer performs the following steps for a vehicle body model including a plurality of vehicle body parts to determine the division positions of the vehicle body parts and / or the vehicle body parts to be integrated. As shown in FIG. 9 , this method includes a vehicle body model acquisition step S1, a sensitivity analysis step S3, and a vehicle body part division position / integration determination step S5. In this embodiment, each of the above steps is executed by a division / integration determination device 1 (see FIG. 1 ) configured by a computer. Each of the above steps will be described below.
[0063] <Vehicle Body Model Acquisition Step> The vehicle body model acquisition step S1 is a step of acquiring a vehicle body model including a plurality of vehicle body parts modeled with a plurality of elements and junctions at which the plurality of vehicle body parts are joined as a part assembly. In this embodiment, the vehicle body model acquisition unit 13 of the division / integration determination device 1 reads the vehicle body model file 21 (see FIG. 1 ) to acquire a vehicle body model 100 including a plurality of vehicle body parts (such as A-pillar lowers 101) modeled with a plurality of shell elements and junctions 121 at which the vehicle body parts are joined as a part assembly, as shown in FIGS. 2 and 3( a) as an example.
[0064] <Sensitivity Analysis Step> The sensitivity analysis step S3 is a step of setting objective conditions related to the vehicle body performance of the vehicle body model 100, constraint conditions related to the volume of the vehicle body model 100, and load / constraint conditions or only load conditions to be applied to the vehicle body model 100, and determining the sensitivity of each element in each vehicle body part that satisfies the objective conditions under the set load / constraint conditions or only the load conditions and constraint conditions. In this embodiment, the sensitivity analysis unit 15 of the division / integration determination device 1 sets the objective conditions, constraint conditions, and load / constraint conditions, and calculates the material density of each element as the sensitivity of each element.
[0065] In the sensitivity analysis step S3, an optimization analysis such as topology optimization may be performed. In this case, the vehicle body parts constituting the vehicle body model 100 are used as a design space, and material density is assigned as a design variable to the elements constituting the vehicle body parts in the design space to perform an optimization analysis process, thereby calculating the material density that satisfies the target conditions under the set constraint conditions and load / constraint conditions for each element in the vehicle body part.
[0066] <<Vehicle Body Component Dividing Position / Integration Determination Step>> In the vehicle body component dividing position / integration determination step S5, a computer determines the positions at which to divide the vehicle body components and / or the vehicle body components to be integrated, in response to instructions from an operator, based on the sensitivity of each element in the vehicle body component determined in the sensitivity analysis step S3. In this embodiment, this is performed by the vehicle body component dividing position / integration determination unit 17 of the dividing / integration determination device 1.
[0067] As described above, according to the method and apparatus for determining the division positions and integration of vehicle body parts in this embodiment, the sensitivity to vehicle body performance is calculated for each element used to model the vehicle body part, and the division positions of the vehicle body parts and the vehicle body parts to be integrated can be determined based on the calculated sensitivity of each element in the vehicle body part.
[0068] Furthermore, by appropriately setting the plate thickness and material properties of the divided body parts and the integrated body parts in accordance with the determination of the dividing positions of the body parts and the body parts to be integrated, it is possible to efficiently and sufficiently improve the performance of the body.
[0069] For example, when the thickness of a divided body part or an integrated body part is changed, the divided body part with a higher sensitivity can be made thicker since it contributes more to the body performance, and the divided body part or integrated body part with a lower sensitivity can be made thinner since it contributes less to the body performance.
[0070] The method and device for determining the dividing position and integration of a vehicle body part according to this embodiment determines the sensitivity of elements in the vehicle body part to the effect on vehicle body performance due to changes in plate thickness and material properties. Therefore, since highly sensitive parts have a large contribution to vehicle body performance, increasing the plate thickness improves vehicle body performance such as rigidity, while low sensitive parts have a small contribution to vehicle body performance, reducing the plate thickness does not reduce vehicle body performance such as rigidity.
[0071] In general, by dividing vehicle body parts into smaller parts and increasing the thickness of the divided body parts, vehicle body performance (weight efficiency) improves relative to the increase in mass. However, by dividing vehicle body parts into smaller parts, the number of dies used to press-form the vehicle body parts increases, and the number of spot welding points used to join the vehicle body parts as part assemblies also increases, resulting in problems such as higher total manufacturing costs. In contrast, according to the present invention, there is no need to divide vehicle body parts into smaller parts than necessary, and it is possible to increase weight efficiency related to vehicle body performance and suppress increases in manufacturing costs.
[0072] In the above explanation, sensitivity analysis is performed using the vehicle body model 100 with the junction points 121 set as is, but differences in the number of junction points 121 set in the vehicle body model may result in differences in sensitivity to vehicle body performance.
[0073] 3B, sensitivity analysis may be performed using a vehicle body model 150 that simulates continuous joining of multiple vehicle body parts by setting all additional joint points 151 that can join component assemblies in addition to joint points 121 spaced 25 to 60 mm apart in the acquired vehicle body model 100 to increase the density of joint points. Note that the vehicle body model 150 has 10,932 additional joint points 151 set at 10 mm intervals.
[0074] 10(b), 11(b), and 12(b) show the results of a sensitivity analysis performed using a vehicle body model 150 in which 10,932 additional joint points 151 have been added to the vehicle body model 100, and the results are used to determine the vehicle body part division positions and the vehicle body parts to be integrated. Here, FIG. 10(b) is a side view of the A-pillar lower 101 and A-pillar upper 103 (FIG. 10(a)) on the front side of the vehicle body model 150, FIG. 11(b) is a top view of the rear side (FIG. 11(a)) of the vehicle body model 150, and FIG. 12(b) is a perspective view of the left side sill outer 117 and wheel house reinforcement 119 (FIG. 12(a)) of the vehicle body model 150. The sensitivities shown in FIGS. 10(b), 11(b), and 12(b) are obtained by setting the same objective conditions, constraint conditions, and load / constraint conditions (see FIG. 4) as those of the present embodiment described above. The body parts in the body model 150 are given the same reference numerals as the body parts in the body model 100 shown in FIG.
[0075] On the front side of the vehicle body model 150 (FIG. 10(a)), as shown in FIG. 10(b), the difference in sensitivity was large, 0.7 or more, at positions other than the boundary between the A-pillar lower 101 and the A-pillar upper 103.
[0076] Therefore, the positions where the difference in sensitivity is greatest are determined as the division positions, which are the lower A-pillar 301 and the upper A-pillar 303 as shown in FIG. 10(c).
[0077] On the rear side of the vehicle body model 150 (Figure 11(a)), as shown in Figure 11(b), the differences in sensitivity between the rear roof rail center 105 and rear roof rail side 107, between compartment center A 109 and compartment side A 111, and between compartment center B 113 and compartment side B 115 were small, at 0.3 or less.
[0078] Therefore, as shown in Figure 11 (c), the rear roof rail center 105 and the rear roof rail side 107 are integrated to form the rear roof rail 305, the compartment center A109 and the compartment side A111 are integrated to form compartment A307, and the compartment center B113 and the compartment side B115 are integrated to form compartment B309.
[0079] On the left side of the vehicle body model 150 (FIG. 12(a)), as shown in FIG. 12(b), the difference in sensitivity of the side sill outer 117 was small, at 0.3 or less, while the difference in sensitivity between the rear part of the side sill outer 117 and the wheel house reinforcement 119 was large, at 0.7 or more. Furthermore, the difference in sensitivity between the A-pillar lower 101 and the front part of the side sill outer 117 was also small, at 0.3 or less.
[0080] Therefore, as shown in Figure 12 (c), the side sill outer 117 is not divided, and further, the side sill outer 117 and the wheel house reinforcement 119 are not integrated but remain divided, the side sill outer 117 is integrated with the A pillar lower 101 to form the A pillar lower 301, and the wheel house reinforcement 119 is not integrated with the side sill outer 117 but forms the wheel house reinforcement 311.
[0081] FIG. 13(b) shows an overall view of the divided and integrated vehicle body model 300 after the division positions and integration of the vehicle body parts have been determined based on the sensitivities shown in FIGS. 10(b), 11(b), and 12(b).
[0082] The difference in effect between using the vehicle body model 100 with the joint points 121 set as described in this embodiment as is and using the vehicle body model 150 with all the additional joint points 151 that can be joined as described in another aspect of this embodiment as being set will be explained in the examples below.
[0083] In the above description, the vehicle body performance is focused on improving the rigidity of the vehicle body. However, when the vehicle body performance is focused on improving crash worthiness or fatigue properties, the sensitivity analysis unit or the sensitivity analysis step may set target conditions related to the crash worthiness or fatigue properties. For example, when setting target conditions related to crash properties, minimizing displacement may be set as the target condition.
[0084] In the present embodiment, the sensitivity analysis unit 15 and the sensitivity analysis step S3 calculate the material density of each element as the sensitivity of each element. However, in the present invention, when a vehicle body part is modeled using a plurality of shell elements, the thickness of each shell element that satisfies predetermined target conditions, constraint conditions, and load / constraint conditions may be calculated, and the calculated thickness of the shell element may be used as the sensitivity of each element.
[0085] In this way, when the thickness of each shell element obtained in the sensitivity analysis is made sensitive, an element with a large thickness indicates a high sensitivity to vehicle body performance, and a shell element with a small thickness indicates a low sensitivity to vehicle body performance. As a result, the thickness of an element calculated in the sensitivity analysis can be an index that represents the sensitivity of each element to vehicle body performance.
[0086] Furthermore, in this embodiment, the sensitivity analysis unit 15 and the sensitivity analysis step S3 perform sensitivity analysis by setting load and constraint conditions that impart a static load. However, in the present invention, load and constraint conditions that correspond to a dynamic load that vibrates the vehicle body may also be set.
[0087] Specifically, prior to the sensitivity analysis, a frequency response analysis or the like is performed on the vehicle body model, and the position, direction, and magnitude of a load to be applied to the vehicle body model corresponding to the deformation state in the vibration mode of the vehicle body model obtained by the frequency response analysis, etc. are determined. Then, the determined position, direction, and magnitude of the load are set as load and constraint conditions, and the sensitivity analysis is performed.
[0088] An experiment was conducted to verify the effectiveness of the method and device for determining the dividing position and integration of vehicle body parts according to the present invention, and the results will be described below.
[0089] In this example, the divided and integrated vehicle body model 200 and the divided and integrated vehicle body model 300 described in the above embodiment were examined for improvements in vehicle body performance compared to the vehicle body model 100 before being divided and integrated.
[0090] In the split and integrated vehicle body model 200 and the split and integrated vehicle body model 300, the thickness of the vehicle body parts after splitting is the same as the thickness of the vehicle body parts before splitting, and the thickness of the integrated vehicle body parts is the thickness of the vehicle body part with the larger surface area among the vehicle body parts before integration.
[0091] The torsional stiffness was calculated by applying the static torsional load and constraint conditions shown in Fig. 4 to the divided and integrated vehicle body model 200 and the divided and integrated vehicle body model 300. Here, the load applied to the load point was set to 1000 N.
[0092] In this example, the torsional rigidity was calculated as follows. First, a line connecting the mounting positions of the left and right rear subframes (corresponding to Q in FIG. 4 ) of the split-integrated vehicle body model was used as a reference (angle 0°), and the mounting positions of the left and right front suspensions on the front side of the vehicle body (corresponding to P in FIG. 4 ) were used as load points. A vertically upward load (1000 N) was applied to one load point, and a vertically downward load (1000 N) was applied to the other load point. The vehicle body tilt angles as viewed from the front of the vehicle body were averaged across the fore-and-aft direction to determine an average tilt angle. The torsional rigidity was then determined by dividing the product of the load applied to the load point and the displacement by the average tilt angle.
[0093] Table 1 shows the results of mass change and torsional rigidity for the divided and integrated vehicle body model 200 and the divided and integrated vehicle body model 300. Note that the spacing between the joint points in each combination of each vehicle body part that constitutes the divided and integrated vehicle body model 200 and the divided and integrated vehicle body model 300 was set to be the same as the spacing between the joint points 121 of the original vehicle body model 100, which was given in advance.
[0094]
[0095] In Table 1, the reference example is the result when the original vehicle body model 100 given in advance before being divided and integrated is used, the invention example 1 is the result when the divided and integrated vehicle body model 200 is used, and the invention example 2 is the result when the divided and integrated vehicle body model 300 is used.
[0096] The mass changes shown in Table 1 are relative changes in the mass of the divided and integrated vehicle body model 200 or the divided and integrated vehicle body model 300 based on the mass of the vehicle body model 100 used as the reference example, and the divided and integrated vehicle body model 200 and the divided and integrated vehicle body model 300 were calculated from the plate thickness of the vehicle body parts.
[0097] Furthermore, the improvement rate of stiffness shown in Table 1 is a relative change in torsional stiffness calculated based on the torsional stiffness of the original vehicle body model 100 (reference example) before the vehicle body parts were divided or integrated, and was calculated using the following formula: Improvement rate of stiffness (%) = (torsional stiffness of invention example - torsional stiffness of reference example) / torsional stiffness of reference example × 100
[0098] The stiffness improvement rate per mass change in Examples 1 and 2 is calculated by dividing the stiffness improvement rate in each of Examples 1 and 2 by the mass change.
[0099] The mass change in invention example 1 was 2.3 kg, and the mass change in invention example 2 was 1.6 kg, and although the mass increased compared to the reference example by dividing and / or integrating the body parts, the rigidity improvement rate was approximately 13% in both invention examples 1 and 2. This shows that dividing and integrating body parts according to the present invention results in a significant improvement in torsional rigidity.
[0100] Furthermore, the stiffness improvement rate per mass change, calculated by dividing the stiffness improvement rate by the mass change, was 5.66% / kg for invention example 1, while it was 8.21% / kg for invention example 2. From these results, it was found that performing a sensitivity analysis using car body model 150 in which all additional joining points 151 that can be joined to car body model 100 are set, and determining the division positions of the car body parts and the car body parts to be integrated, eliminates the effect of the joint point arrangement on car body performance and makes it possible to more accurately calculate the sensitivity of each element of the car body part, thereby more efficiently improving car body performance with respect to the mass change due to division and integration.
[0101] According to the present invention, it is possible to provide a method and device for determining the dividing positions and integration of vehicle body parts, which can efficiently and sufficiently improve vehicle body performance.
[0102] 1 Division / integration determination device 3 Display device 5 Input device 7 Storage device 9 Working data memory 11 Arithmetic processing unit 13 Vehicle body model acquisition unit 15 Sensitivity analysis unit 17 Vehicle body part division position / integration determination unit 21 Vehicle body model file 100 Vehicle body model 101 A-pillar lower 103 A-pillar upper 105 Rear roof rail center 107 Rear roof rail side 109 Compartment center A 111 Compartment side A 113 Compartment center B 115 Compartment side B 117 Side sill outer 119 Wheel house reinforcement 121 Joint point 150 Vehicle body model 151 Additional joint point 200 Divided and integrated vehicle body model 201 A-pillar 203 Rear roof rail 205 Compartment A 207 Compartment B 209 Side sill outer front 211 Side sill outer rear 300 Split and integrated body model 301 A-pillar lower 303 A-pillar upper 305 Rear roof rail 307 Compartment A 309 Compartment B 311 Wheelhouse reinforcement
Claims
DEPCT661. Method for Locating, Separating, and Integrating Automotive Components. For locating the separation of automotive components and / or more than one automotive component to be integrated, the following steps are performed by a computer for a vehicle body model including more than one automotive component. The method includes: a process for acquiring a vehicle body model that includes more than one automotive component modeled by more than one component and connection point where more than one automotive component is connected as an assembly; and a process for target sensitivity analysis relating to the potential of the vehicle body model, limitations relating to the volume of the vehicle body model, and load conditions and limitations or simply load conditions applied to the vehicle body model.and the acquisition of the sensitivity of each component in each vehicle part that matches the target under load and limit conditions or just under load and limit conditions; and the vehicle part allocation, separation and integration site determination procedure of determining the location where the vehicle parts are separated and / or the vehicle parts to be integrated based on the sensitivity of each component in each vehicle part.
2. The vehicle part allocation, separation and integration site determination method according to claim 1, where, in the sensitivity analysis step, the component density of each target component is calculated, and the calculated component density is used as the sensitivity of each component.
3. The vehicle part allocation, separation and integration site determination method according to claim 1 or 2, where, in the vehicle body model acquisition step,All other connection points at which assembly parts can be connected are set to the acquired vehicle body model, apart from connection point 4. Vehicle part separation and integration positioning device for determining the separation of vehicle parts and / or more than one vehicle part to be integrated for a vehicle body model including more than one vehicle part as an assembly: a vehicle body model acquisition unit which is configured to acquire a vehicle body model including more than one vehicle part modeled by more than one component and connection points at which more than one vehicle part is connected as an assembly; a sensitivity analysis unit which is configured to set targets related to the vehicle body potential of the vehicle body model, limitations related to the volume of the vehicle body model, and load conditions and limitations or just load conditions applied to the vehicle body model.and obtain the sensitivity of each component in each target vehicle part under load and limit conditions or just the load and limit conditions; and the vehicle part separation and integration locating unit which is configured to determine the location where vehicle parts are separated and / or vehicle parts to be integrated by operator commands based on the sensitivity of each component in each vehicle part.
5. The vehicle part separation and integration locating unit under claim 4, where the sensitivity analysis unit is configured to calculate the component density of each component in each target vehicle part, and use the calculated component density as the sensitivity of each component.
6. The vehicle part separation and integration locating unit under claim 4 or 5, where the vehicle body model acquisition unit is configured to set all other connection points at which the component assembly can be connected to the acquired vehicle body model in addition to the connection points;