Mesh Variables Mapping Method And Its Application In Design And Manufacturing For Car Body

The research of automotive body crashworthiness and lightweight has a greatsignificance for automobile industry. Based on car body crashworthiness analysis andinfluence of stamping die for lightweight body, we did the research on the meshvariables mapping method and its application in car body design and manufacture bythis paper, which can be described as follow:First of all, a new mapping method for mesh variables is proposed in this study. Itcontains two aspects: one is a new mapping method for mesh variables based on aninverse isoparametric mapping. In this method, the mesh variables, such as thicknessdistribution, stress and strain, which are transfered from the sheet metal formingmodel to crash model. Another is a load mapping method for die structure analysis. Itestablishes a relationship of load mapping between deformed sheet metal and thestamping die.Secondly, a case study is conducted to adopt the new mapping method in thecrash simulation analysis for a car front bumper bar, to analyze how the sheet metalforming effects, which retained in parts, influence the crash simulation. We comparedthe analysis result between the traditional model and crash model with the formingeffects. Obviously, it is necessary to consider the forming effects in car crashsimulation analysis. The accuracy for vehicle crash simulation is improved with thisapproach.Finally, through the load mapping method, the load distribution as load boundaryconditions on the surface of the die can be attained for topology optimization analysisof stamping die structures. According to the topology optimization results, were-design the stamping die structure. Then, based on the optimized design and theinitial stamping die in the same boundary conditions, we also make a structurestrength analysis and compare displacement, stress and strain distribution between twodesigns, in which the optimized design die fully meets the stiffness requirement.The research results indicate that the new proposd method can accurately deliverthe mesh variables between different models and it is valuable to improve theprecision of the crash simulation analysis and die structure optimized design.