Assessment of Motorcycle Helmet Chin Bar Design Criteria with Respect to Basilar Skull Fracture using FEM

Statistical studies showed that the chin bar of full-face helmets is the region with the highest number of impacts. In an Australian research, fifty percent of severe impacts took place to the front of the helmet and forty percent of these resulted in Basilar Skull Fracture (BSF). There are two standards, which include criteria for assessing the performance of the helmet’s chin bar, Snell M2015 and ECE 22.05. These standards have developed some methods for testing the chin bar in order to protect the head from facial impact during motorcycle accidents, but they do not seem to consider head and neck injuries. The present work has utilized the finite element method to assess the Snell M2015 and ECE 22.05 criteria for chin bar design with respect to the injuries at the base of the skull. In the first step, the fem model has been mounted on a headform to simulate the chin bar test for both standards. In the next step, the Hybrid III dummy model has been coupled to the helmet to simulate the response of the whole body, in particular at head and neck connection, to the facial impact. Finally, the results obtained from the dummy model simulations have been utilized to assess if the standards could provide reasonable criteria for BSF. The simulations are performed with LS-Dyna and the focus of the assessment is about the injuries at the intersection between skull and spine.