Abstract
Research and/or Engineering Questions/Objective:
In the previous platform development process, it is often design a single model, based on this model to make changes, derived from other models, this will lead to common structure doesn’t suitable for the late development of models, and it must be maintained couldn’t be changed, so the change and optimize space is very small. If from the early concept design phase, using the implicit parametric modeling and CAE automatic optimization technology, optimize the overall performance of all the models within the program developed, can obtained the common structure of each vehicle performance reach the best, avoid mass recall.
Methodology:
A full parametric BIW model is built by SFE Concept software. The parameters model can be changed fast, and remain continuity, automatically divided into mesh, and which can generate the weld and glue, according to the connection information. The model consists of three parts:the common parts of the hatchback and sedan, the tail structure of hatchback and the tail structure of sedan. Hatchback and sedan tail structure can be replaced by each other, connection with the common parts, get the complete BIW of hatchback or sedan. Design and optimize mode, bending and torsion stiffness, dynamic stiffness, crash performance and weight of the hatchback and sedan BIW at the same time, include topology optimization, shape optimization, thickness optimization and crash performance verification. Because the tail of the structure is independent, and the performance of the other models is not affected by each other, so the optimization of each steps are only for the common structure.
Results:
Mode, bending and torsion stiffness, dynamic stiffness as constraints, mass as the target of optimization, compared with the initial design of BIW, all of the performance including crash performance can meet the design requirements, and the mass reduce 15.16kg.
Limitations of this study:
In the early phase of development, should be as much as possible to consider the needed to develop models, all the models should be designed and optimized at the same time, otherwise it may cause the problem of optimizing difficult or over design. Otherwise, on this basis need more detail and reasonable optimization for tail structures of hatchback and sedan.
What does the paper offer that is new in the field including in comparison to other work by the authors?
Optimize common parts at the same time, to ensure that the results for each vehicle's performance are good. And based on the method proposed previously by the authors, optimization of the dynamic stiffness performance was added to the automatic optimization process.
Conclusions:
Implicit parametric modeling and CAE technology provide better support for platform and modularization development. The structure of each position can constitute a module, and in the same position can be replaced easily and quickly, while remain continuity, and it can be used repeatedly to reduce duplication modeling. With the increase of structures, the model database can be formed.Because of it occupy large computer resources, and the accuracy of the approximate mathematical model is not enough, suggest that optimize crash performance by artificial, doesn’t considered in the automatic optimization process.
KEYWORDS : Platform development, Modular, Parametric modeling, Lightweight, SFE Concept