Front-End Structural Crash Energy Management Concept for a Sport Utility Like Aluminum Vehicle

Abstract

Abstract Front-end structural concepts used to enhance the crash energy management of a sport utility like aluminum vehicle are discussed in this paper. These structural concepts were applied to the front-end rails, subframe, and subframe extension. Epoxy-based foam reinforcement was applied to the 5754 aluminum front end rails, shearing was applied to the cast-hydro formed tubular subframe, and a new load path was implemented in the front end structure in the form of a subframe extension. Deceleration-time response was developed and benchmarked against target double plateau square pulse at the early stage of the design. Vehicle front-end design and analysis for US-NCAP 35 mph full frontal crash were conducted using concept and detailed nonlinear finite element codes. Concept modeling tools that were used in the initial design stages involve collapsible nonlinear beam finite element, strength and stability, and spring mass system codes. Detailed finite element code RADIOSS was applied to the analysis of the final front-end structural design. Occupant responses and injury numbers were evaluated using MADYM03D rigid body and finite element code. Concept vehicle crash safety protection was evaluated and star-rated then benchmarked against 2000 and 2001 production SUVs. A paper study was conducted on a higher strength less ductile 6111T6 stamped aluminum alloy to further enhance the structure and enhance dash and floor intrusion. Structural collapse mode, deceleration-time response, and occupant simulation results show a good performance of aluminum front-end structures in managing crash energy and protecting vehicle occupants.