Optimization of Bumper Beam Structure for Pedestrian Protection and Low Speed Bumper Impact

The biggest challenge in vehicle BIW design today is to make a light, cost effective and energy absorbing structure. With the increasing competition as well as increasing customer awareness, today’s vehicle has to satisfy several aesthetic and functional requirements besides the mandatory regulatory requirements. While working on global platform, it is challenging to comply with both pedestrian protection and low speed bumper impact (ECE-R42) and at the same time meeting the styling intent of reducing the front overhang. Pedestrian lower leg compliance demands space between bumper member and bumper, a condition that reduces the space available for energy absorption during low speed impact (ECE-R42). Therefore, reduction in front overhang poses a problem in meeting both the requirements with limited space. This paper outlines vehicle case study in order to optimize the design of Bumper Beam structure, for complying with regulatory requirements while satisfying the styling intent. Various combinations of sections have been checked in simulations for evaluating strength, weight and cost. Research has also been done on material and thickness variations to reach an optimized structure. The paper throws light on the various combinations of bumper beam structures such as pipes and sheet metal structures to prevent investment in costly process technology like hot forming or Advance high strength steels. The result showcases a balance of cost, weight and strength for Bumper Beam.