Abstract
Although modern body and head protective gears are well studied by experts, innovators, and manufacturers, incidence of sports-related injuries is still very high in the United States and all around the world. To reduce the negative effects from blunt impact, an impact reduction structure which contains a channel, shell, and dual-cells was designed and developed with the intention of improving existing helmet liners. This study utilized a previously proven interconnected-cells concept, where a primary cell compresses, then air inside the cell transfers to a secondary cell which expands accordingly, causing impact reduction. While the concept remained the same, a new dual-cells architecture was explored, with numerical and experimental studies for helmet liner impact reduction, and compared to a commercial Xenith helmet liner element. The simulation study began with exploring the effect of adding corrugation to the walls of both cells on impact behavior, then persisted with optimizing impact reduction structure design, and finalized with a comparison study. An experimental study was performed with the optimized structure, provided by simulation, and compared against commercial Xenith helmet liner element in terms of reaction force, linear acceleration, and impact duration. Experimental and simulation results showed that our impact reduction structure provides lower reaction force and linear acceleration.