Shape Optimization to Improve Energy Absorption Ability of Cylindrical Thin-Walled Origami Structure

Abstract

During car frontal crash, crush energy is absorbed by the parts of front bumper, front side member, front panel member and so on. Previous research has indicated that front side member plays major role in energy absorption. For protecting the passengers, the front side member is expected to absorb crush energy as much as possible. In this study, we adopt cylindrical thin-walled structure using origami engineering as front side member instead of structure with rectangular cross section which is generally used. We develop an optimization system of the cylindrical thin-walled origami structure, in which the objective function is to maximize the energy absorption of origami structure; the design variables are structural parameter, number of divisional sections along axis, number of edges of polygonal cross section and number of subdivision levels; the weight and initial peak load of optimal structure must be less than those of structure with rectangular cross section. We then discuss the optimization results that the optimal structure is capable of absorbing energy 91% more than that of original rectangular cross sectional structure which is usually bended on the way of being crushed, 37% more than that of original structure which is ideally crushed to 70% length without bending.