Assessment and Measurment of Potential Blunt Trauma Under Ballistic Helmets

This paper investigates measurement techniques to evaluate ballistic impact protection in terms of head contact loads from non penetrating impacts on helmets. An aluminium head form instrumented with piezo-electric transducers, film sensors and accelerometers was used to measure impact forces applied by the back face deformation of helmets after ballistic impacts. The head form and an instrumented accelerated weight machine are also used to measure impact forces applied to the helmet and forces transmitted behind the helmet.Radius of curvature of back face deformation data were also collected from ballistic impacts on helmets mounted on conditioned plastilina® and was shown to correlate with published studies from Wilber [4] and Byers [5] which established a correlation between the force required to fracture a human skull and radius of curvature of the striker. It is shown that backface deformation of potentially damaging levels can be generated behind typical ballistic helmets.