The safe performance of current helmet for American football is evaluated by the standard of NOCSAE, National Operating Committee on Standards for Athletic Equipment. However the evaluation does not consider that head injury is developed by repeated impacts and a risk of shortened protection performance by the aged deterioration of buffer materials. Therefore, final objective of this study is to establish a new standard considering the influence of them. However in evaluation of helmet, a dummy head which can get acceleration is necessary. Accordingly, this paper intends to create it which indicates the acceleration reply like a conventional dummy head and to evaluate it by drop test. Self-making dummy head is made of urethane foam because it is easy to work and mold. As a result of drop test, the buffering performance of self-making dummy head is not suitable for the evaluation of head injury. Then it is necessary to ensure the buffering performance by changing physical property of urethane foam. From compression test for urethane foam, it is found that young's modulus and yield point are correlated to density. Therefore, after this, it is necessary to inspect the density that is suitable for dummy head under impact load.
衝撃荷重下における人頭模型の緩衝性能
jsme_2015_G0300504
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