Automotive Body Components Structural Optimization Based On Robust Design

As one of four assemblies of the automotive, the body has an important influenceon the performance of the automotive. With the development of the automotiveindustry, the requirements of the body performance are increased. The body structuraloptimization has been the research focus of automotive industry. Actually, there aremany uncertain factors in the process of manufacture and use of the body, such asmanufacturing precision, material properties, environmental conditions and so on.Unfortunately, because of neglecting these uncertainty factors, the body structuralperformance is unstable. Under certain conditions, the design may beyond theconstraints and fails. With the robust design achieved a very significant effect inmany areas of scientific research and production, researchers also introduced therobust design to the automotive industry. In this paper, robust design method isintroduced to the process of body structural optimization. The main contents are asfollow.(1) Some researches about ensemble of surrogates. By numerical examples, westudy the feasibility of ensemble of surrogates and its prediction accuracy is verified.The results show that, compared with single surrogate model, though ensemble ofsurrogates has no obvious advantage, but it is not sensitive to sampling method andcan be more stability. When build ensemble of surrogates, u sing high predictionaccuracy single surrogate will improve the prediction accuracy of ensemble ofsurrogates.(2) Body crashworthiness robust optimization based on dual response surfacemethod. We study the crashworthiness robust optimization of one automotive frontthin wall structure. For existing studies only consider only a single type of uncertaintyfactors, in this paper, we consider the uncertainty of panel thickness and materialparameters. Also, we propose a new kind of quality characteristics mean and standarddeviation calculation method. Ensemble of surrogates is used in this research. Theresults show that, after robust optimization, not only the front rail crashworthinessperformance meets the design requirements but also the robustness is improved andthe front rail’s weight also is reduced.(3) The application of Taguchi parameter design in automotive door structur aloptimization is presented in this paper, considering the fluctuations of the materialparameters and load cases. Through Taguchi method, the door panels which are sensitive to the automotive door sag stiffness and the fundamental frequency arefound. The automotive door robustness improves by reasonable panel thicknesscombination, while reducing the weight of the door.The results of this study show that, by using robust design method, not only theperformance of the body structure can be improved, but also reduces the impact ofuncertainties, improves the robustness of the performance of the body structure, androbust design method has a strong engineering practicality. This paper also provides areference method for body lightweight design.