Crash box

About: Crash box is a research topic. Over the lifetime, 516 publications have been published within this topic receiving 3771 citations.

Energy Absorption of Thin-Walled Square Tubes With a Prefolded Origami Pattern—Part I: Geometry and Numerical Simulation

Abstract: Thin-walled tubes subjected to axial crushing have been extensively employed as energy absorption devices in transport vehicles. Conventionally, they have a square or rectangular section, either straight or tapered. Dents are sometimes added to the surface in order to reduce the initial buckling force. This paper presents a novel thin-walled energy absorption device known as the origami crash box that is made from a thin-walled tube of square cross section whose surface is prefolded according to a developable origami pattern. The prefolded surface serves both as a type of geometric imperfection to lower the initial buckling force and as a mode inducer to trigger a collapse mode that is more efficient in terms of energy absorption. It has been found out from quasi-static numerical simulation that a new collapse mode referred to as the completed diamond mode, which features doubled traveling plastic hinge lines compared with those in conventional square tubes, can be triggered, leading to higher energy absorption and lower peak force than those of conventional ones of identical weight. A parametric study indicates that for a wide range of geometric parameters the origami crash box exhibits predictable and stable collapse behavior, with an energy absorption increase of 92.1% being achieved in the optimum case. The origami crash box can be stamped out of a thin sheet of material like conventional energy absorption devices without incurring in-plane stretching due to the developable surface of the origami pattern. The manufacturing cost is comparable to that of existing thin-walled crash boxes, but it absorbs a great deal more energy during a collision. [DOI: 10.1115/1.4024405]

Body structure for motor vehicle

Abstract: A side body structure of a motor vehicle includes a first and second crash boxes at the connecting portion of a side sill and a rear wheel arch. The first crash box is provided outside of a side sill reinforcement and the second crash box is inside the side sill reinforcement. The second crash box is connected with a cross member extended in a transversal direction of the vehicle. In the event of a side impact, first the first crash box collapses and then the second crash box does. Finally, the impact energy is transferred to and absorbed by other body structures through the cross member. The side sill portion and the rear wheel arch portion can be prevented from intruding into a rear compartment so as to save passengers from serious injury.