Shape Optimization for Automotive Thin Sheet Structures

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Structural bodies, particularly those in automobiles, face challenges in applying optimization techniques due to difficulties in configuring thin sheet structures as independent design spaces and reflecting loads and constraints within these spaces, limiting the effectiveness of optimization methods like topology optimization.

Innovation Solution

A method and device for shape optimization that utilize two-dimensional and three-dimensional elements to create an optimization block model, connected to the structural body model, allowing for multi-body dynamics analysis to find an optimum shape, with specific material property settings and discretization techniques to accurately simulate load transmission and deformation.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Weight of moving object

If topology optimization is applied to thin sheet structures in automotive bodies, then weight reduction and stiffness improvement can be achieved, but it is difficult to configure thin sheet structures as independent design spaces and reflect loads and constraints within these spaces

Engineering Contradiction:
Improveweight of automotive bodyVSAvoidcomplexity of design space configuration
Core Design Contradiction:
Weight of moving objectVSDevice complexity

Solution Approach 1:

The patent divides the automotive body into multiple design spaces, each corresponding to a specific component or region (e.g., door inner panel, dashboard). This segmentation allows topology optimization to be applied independently to each thin sheet structure while maintaining proper load reflection and constraint application within each designated space.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The patent introduces an intermediary modeling approach where thin sheet structures are represented as three-dimensional solid models with equivalent stiffness properties. This intermediary representation enables proper load reflection and constraint application while maintaining the essential mechanical behavior of the original thin sheet structure.

Inventive Principle:
Principle #24Intermediary (Mediator)

2Measurement precision

If three-dimensional elements are used for optimization analysis, then accurate load reflection and shape optimization can be achieved, but it becomes difficult to appropriately reflect the optimized shape back in thin sheet structures

Engineering Contradiction:
Improveaccuracy of load reflectionVSAvoidease of implementing optimized shape in thin sheets
Core Design Contradiction:
Measurement precisionVSEase of manufacture

Solution Approach 1:

The patent transforms the optimized three-dimensional shape results into two-dimensional sheet metal forming parameters through coordinate extraction and surface fitting techniques. This parameter transformation enables the optimized shape to be accurately represented in terms of bending lines, curvature, and other sheet metal specific parameters that can be directly used in manufacturing.

Inventive Principle:
Principle #35Parameter changes

Solution Approach 2:

The patent performs dimensionality reduction by converting three-dimensional optimization results back into two-dimensional sheet metal representations. This involves extracting key geometric features from the 3D optimized model and representing them as 2D patterns with appropriate bend allowances and forming parameters suitable for thin sheet fabrication.

Inventive Principle:
Principle #17Another dimension (Dimensionality change)

3Strength

If mathematical optimization techniques are applied to structural bodies, then stiffness improvement and weight reduction can be achieved, but the techniques do not provide means for solving problems specific to thin sheet structures receiving external forces

Engineering Contradiction:
Improvestiffness of structural bodyVSAvoidadaptability to thin sheet structures under external force
Core Design Contradiction:
StrengthVSAdaptability or versatility

Solution Approach 1:

The patent incorporates dynamic loading conditions and constraint applications specific to thin sheet structures in the optimization process. By considering realistic external forces, boundary conditions, and deformation patterns that thin sheets experience in service, the optimization results are directly applicable to actual automotive body components under operational loads.

Inventive Principle:
Principle #15Dynamics

Solution Approach 2:

The patent applies localized optimization strategies tailored to thin sheet structures, considering region-specific material properties, thickness variations, and local loading conditions. This allows the optimization to account for the unique mechanical behavior of thin sheets in different areas of the automotive body, such as door panels versus dashboard components.

Inventive Principle:
Principle #3Local quality

Data Source

PatentEP2953041B1Method and device for analysis of shape optimization
Publication Date: 2024.12.11 JFE STEEL CORP
  • EP2953041B1 patent drawingFigure 1
  • EP2953041B1 patent drawingFigure 2
  • EP2953041B1 patent drawingFigure 3~4A

AI summary

When a part of a structural body model having a movable portion is optimized by using two-dimensional elements or three-dimensional elements, a portion to be optimized in the movable portion is set as a design space and an optimization block model formed of three-dimensional elements and to be subjected to analysis processing of optimization is generated in the set design space. The generated optimization block model is connected with the structural body model and a material property is set for the optimization block model. An optimization analysis condition for finding an optimum shape of the optimization block model is set, and a multi-body dynamics analysis condition for performing multi-body dynamics analysis on the structural body model, with which the optimization block model has been connected, is set. Based on the set optimization analysis condition and multi-body dynamics analysis condition, multi-body dynamics analysis is executed with respect to the optimization block model, and the optimum shape of the optimization block model is found.