基于可制造性约束的车身变截面梁关联优化设计

Associated optimization for the variable cross-section beam of vehicle body based on the manufacturability constraints

在车身主断面设计过程中,变截面梁的设计一直存在较多问题,其形状设计受到结构性能和可制造性因素的多重约束。文中对车身变截面梁的设计问题进行了研究,通过构造基于工程约束的形状优化关联设计变量,建立了车身薄壁结构的多截面关联优化设计算法,实现了考虑可制造性约束的变截面梁优化设计方法,还可支持多种材料设计。同时提出了适合工程优化的最优解选择评分公式,实现了最优解的自动选取。该方法既可以应用于正向设计过程中车身主断面的变截面梁轮廓线的确定,也可对现有梁的结构性能的改进优化,实现制造成本降低和车身轻量化设计。文中给出具体的变截面梁关联优化算法,并通过某车型B柱截面优化实例验证了该算法的有效性。

For the design of the main section of vehicle body,many problems are found in terms of the variable cross-section beam.Its shape is subject to multiple constraints,such as structural performance and manufacturability.In this article,the analysis is conducted on the design of the variable cross-section beam of vehicle body.Those shape-associated optimization variables are identified based on the engineering constraints,in order to work out the algorithm of multi-section associated optimization,which is suitable for the thin-walled body structure,and thus the variable cross-section beam is optimized with the manufacturability constraints taken into account.Besides,this method creates favorable conditions for the design of multiple materials.At the same time,the formula for selection and scoring of the optimal solution is worked out,which is used for engineering optimization,and thus the optimal solution is selected in an automatic manner.This method can be applied to identify the contour of the variable cross-section beam of the main section in the process of forward design on one hand and improve the existent beam’s structural performance on the other hand,so as to reduce the manufacturing cost and ensure the lightweight design of vehicle body.This specific algorithm of associated optimization is illustrated,and an example of the B-pillar cross-section optimization proves that this algorithm is effective.