Development of Open-Source Dummy and Impactor Models for the Assessment of American Football Helmet Finite Element Models
The objective of this study was to develop and validate a set of Hybrid-III head and neck (HIII-HN) and impactor models that can be used to assess American football design modifications with established dummy-based injury metrics. The model was validated in two bare-head impact test configurations used by the National Football League and research groups to rank and assess helmet performance. The first configuration was a rigid pendulum impact to three locations on the HIII head (front, rear, side) at 3 m/s. The second configuration was a set of eight 5.5 m/s impacts to the HIII head at different locations using a linear impactor with a compliant end cap. The ISO/TS 18571 objective rating metric was used to quantify the correlation between the experimental and model head kinematics (linear and rotational velocity and acceleration) and neck kinetics (neck force and moment). The HIII-HN model demonstrated good correlation with overall mean ISO scores of 0.69–0.78 in the pendulum impacts and 0.65–0.81 in the linear impacts. These publically available models will serve as an in silico design platform that will be useful for investigating novel football helmet designs and studying human head impact biomechanics, in general.
KeywordsHybrid-III Anthropomorphic test device Helmet impact testing Computational model Material properties
The research presented in this paper was made possible by a grant from Football Research, Inc. (FRI) and Biomechanics Consulting and Research, LLC (Biocore). The views expressed are solely those of the authors and do not represent those of Biocore, FRI, or any of their affiliates or funding sources. The authors would like to thank our collaborators in the “Engineering Roadmap: Numerical Crowdsourcing Project” for their support and feedback of this work (teams from Wake Forest University, University of Waterloo, and KTH Royal Institute of Technology). The authors also acknowledge Virginia Tech Helmet Lab and BioKinetics and Associates, Ltd. for generating the pendulum and linear impactor test data.
Conflict of interest
Co-author Kent is co-owner of Biomechanics Consulting and Research, LLC (Biocore). All other authors declare no conflicts of interest.
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