FE Modeling of Innovative Helmet Liners

A key component of a safety helmet is the energy absorbing liner, which absorbs the greatest portion of impact energy during an accident. The aim of the present work was to study innovative structures for energy absorption that minimize the likelihood of head injuries for standard impact cases. The innovative helmet liner consists of an ABS plastic lamina with deformable cones on it. Energy is absorbed via a combination of folding and collapsing of the cones. The main advantage that such liner may introduce over common EPS pads is that it allows a better optimization of energy absorption for different impact sites and configurations. Numerical crash simulations of the novel liner employed in a ski helmet were carried out with LS-DYNA®. The model reproduced the testing conditions defined by the standards EN1077. Experimental and numerical results were compared and possible causes of discrepancies were discussed. The finite element model so validated paves the way for a future numerical parametric optimization of the novel structure. Keywords: Helmet, Crashworthiness, Energy Absorbing Structures, Drop testing