自動車車体における構造知見の効率的発見のための設計支援技術の開発

（2）荷重伝達指標（U*）を基にした動的可視化分析手法の提案

抄録

We propose the dynamic visualization method using load transfer analysis (U*).It is important to find an effective countermeasure structure by analyzing the causes of the bottleneck about car body stiffness for weight reduction. Important parts of car body stiffness are bottlenecks for weight reduction in automotive product development. As a method to predict the load transfer, load transfer analysis (U*) has been proposed. However, it is difficult to predict the load path only from the contour lines of U* values for complex structures such as car body structures. Therefore, we propose the dynamic visualization method that divides the U* value evenly and visualizes it continuously and dynamically from 1.0 to 0.0 in U*. This method expresses artificially the load transfer flow and make designers and engineers find weak structures based on the difference from the designer's concept or hypothesis in automotive body design. As a result of applying this method to car body structure for body stiffness, it was found that the weak points were concentrated in the parts on the side of the vehicle structure. Furthermore, by changing the joining method of the side parts of car body structure, we were able to improve the load transfer flow of U* and found the structure that was 9kg lighter than the base structure, subject to body stiffness, side crash and low frequency eigenvalue.