Evaluation of the Head Protection Abilities of Helmets under Impact Loadings by FE Analysis.

Abstract

Many requirements such as safety, lightness and comfort are necessary to helmets for sports and riding. Many studies regarding basic functions of helmets including safety problems were reported. In the previous studies on safety problems, however, it seems to be difficult to say that those studies were accurate reviews because a helmet model integrated with a headform model or a simplified helmet model different from a real one had been used in their simulations. In this paper, FE models were made from the real shapes of the full face type helmet of JIS C Snell and the headform of the Hybrid-III dummy model, which were used in the drop impact tests. Computer simulations for the falling impact of helmets with headform onto playing surfaces were conducted by using FE models. In simulations, the material properties of shell and liner of helmet were determined as elastic and the headform was assumed as a rigid body. As a result, the acceleration responses of headform from the simulated results were compared with those of drop impact tests to evaluate the head protection abilities of the helmet by comparing HIC values. Additionally, the parametric studies were conducted to investigate the factors that affect mainly the headform acceleration. From this study, the main physical parameters, which are important in the optimal design of helmets under impact loadings, can be decided.