Abstract
Keywords:
ASF(Aluminum Space Frame), RSM(Response Surface Model), Multidisciplinary design constraints
Abstract
This paper presents an Aluminum Space Frame (ASF) vehicle body design optimization, which minimizes the B.I.W. weight and satisfies the multidisciplinary design constraints such as static stiffness, vibration characteristics, low- and high-speed crash performances, and occupant safety. As only one cycle CPU time for all the analyses is 11 hours, the ASF design having 11-design variable is a large scaled problem. In this study, ISCD-II and conservative least square fitting method were used for efficiently constructing the quadratic response surface models (RSM). Likewise, the ALM method was used to solve the approximate optimization problem based on the RSM. The approximate optimum was sequentially added to remodel the RSM for the next iteration. The proposed optimization strategy requires only 20 analyses to solve the 11-design variable design optimization problem. Moreover, the optimal design can achieve 15.7% weight reduction compared to the ASF base model while satisfying all the multidisciplinary design constraints.