In contrast, in an ongoing test program led by one of the authors, porcine subjects placed fully inside the shock tube resulted in negligible head accelerations and little evidence of neurological trauma, even with more than double the peak overpressure of the other tests. For military helmets, the shell serves the dual purpose of both blunt impact and foreign body penetration protection. Appl Math Comput 96 1: Ongoing research with collegiate football teams 49 and joint Department of Defense and National Football League data collection efforts should result in prospective data that will provide valuable insights into the threshold loads for brain injuries that occur in the absence of a skull fracture. Next, the vertical petals of the head form create a rigid boundary condition that influences the back face deformation measurement. Previous studies have indicated that impact with the ground secondary injury would also result in higher global head accelerations, but this and other tests, supported by pathological data that lack reports of secondary insults, suggest otherwise.
Guo [ 37 ] also gave the same conclusion as Baker.
Considering the similarity between impact crater and explosion crater and the impact pressure attenuation, Kadono and Fujiwara [ 41 ] established a crater depth calculation method for projectile ranges from unbroken to eroded by introducing a dimensionless coefficient: In low-velocity wounds, the injury is made primarily by either crushing or cutting tissue along the path. Unfortunately, although the PEEPsite head form addresses the issue of rigid boundary conditions, issues with respect to clay calibration and achieving accurate measurements of back face deformation remain, as well as the lack of clinical validation. Animal testing has the advantage of providing a means of obtaining physiological response data. Plast Reconstr Surg 6: The WSTC predicts injury based upon the maximum acceleration over a given duration that can be tolerated without leading to a skull fracture. The crater depth is not related to the impact velocity but projectile length and where and are the densities of projectile and target, resp.