Part 581, IIHS Damageability and Lower Leg Impact Compliant Bumper - Challenges and Solutions

The worldwide involvement in global technical regulation (GTR) discussion shows the increasing importance of pedestrian safety as a global concern. In the US, bumper systems are designed for the Part 581 bumper standard and IIHS (Insurance Institute of Highway Safety) bumper structural test protocols. There has also been discussion in the North American automotive industry about the merits of incorporating some measure of pedestrian protection into their systems as well. Compliance with the potential pedestrian leg requirements creates a design conflict with current bumper damageability standards and possibly CAFÉ laws. The difficulties of designing a bumper system that is rigid enough to protect the vehicle in low speed crashes and, at the same time, compliant enough to protect a pedestrian raise questions as to whether these ideas are compatible.

This paper presents reasonable means by which to manage lower leg impact, Part 581 bumper standards and IIHS bumper damageability assessment criteria in a styling and cost structure way, which is typical of today's automotive industry. The proposed approach is validated over a generic vehicle platform through extensive computer-aided engineering (CAE) and subsystem level testing.