A multidimensional approach to the generation of helmets' design criteria: a preliminar study

The design and development process of helmets incorporates systematically design criteria related to safety to accomplish European and local standards for the commercialization. However, there are few studies focused on user's comfort and adaptation. Present study tackles a multidimensional approach to gain better understanding of the interaction between helmet and user to generate design criteria for the internal helmet surface. Morphological characteristics of the target population, pressure distribution over head and subjective perception of fitting and discomfort are the factors considered to establish the criteria that assure a proper fit. Ten men corresponding to helmet size M and usual drivers of motorbike wore two helmet models in three sizes (S, M and L). The head shape of participants was acquired using the head scanner of I-Ware laboratory and an instrumented pad was used to measure pressure in five head regions. After wearing the helmet, users filled in a perception questionnaire about fitting, comfort and usability considering the five regions. Users' fitting perception provided the relation between pressure levels and the comfort felt in the five regions. This study constitutes a first approach to a new methodology to generate criteria to improve the design of helmets under a multidimensional approach.