Evaluation of Head Impacts on Football, Hockey & Lacrosse Helmets

Despite improvements in helmet design over the years, traumatic brain injury cases (TBI) from heavy contact sports have increased drastically. Newer understanding of said cranial injuries has granted scientists and engineers the capability to develop acceleration measuring devices to precisely quantify and simulate real life impacts. In this research, various football, lacrosse and hockey helmets were stricken on a head form using an impulse hammer that measures transient accelerations. Once data was collected, specifically defined metric plots were generated that provided a normalized analysis of all the helmets’ mitigation abilities. These plots revealed that the lowest translational acceleration metric hailed from the lacrosse CPRX-3 which was approximately 0.3 and the highest value came from the hockey Bauer-3 which was around 1.4. The respective rotational acceleration metrics had a low of 0.45 (CPRX-3) and a high of around 1.85 (Bauer-3). The Bauer helmet clearly developed a trend of having a lower impact mitigating ability than the lacrosse across all helmets tested. These experiments affirmed that helmets in general were better at mitigating translational accelerations than rotational accelerations – the latter being known notoriously for causing concussions

Development of Standard Criteria to Evaluate the Effectiveness of Helmets at Decreasing the Risk of Concussions

In many sports, such as American football, accumulations of mild traumatic brain injuries have been suggested as a possible link to neurodegeneration and future mental disorders. With head impacts occurring at all levels of competition and in different sports, it is critical to develop an accurate method for quantifying the effects of head impacts and determining the efficacy of helmets. This study examines the derivation of different dimensionless numbers and ascertains the critical factors needed to predict the effects of head impacts, specifically the resulting accelerations from an impact. Given a known force of impact, parameters such as peak translation acceleration and impact duration were collected for a total of 200 impacts at 10 locations around the head. These parameters were used in conjunction with dimensionless numbers to compare various helmet designs across sports. Five input and four output criteria, or π variables, were derived using fundamental variables of total mass, width of neck, and the difference between muscle reaction time and the impact duration. By determining the coefficients of the governing equations for each output π variable, the impulse of impacts had a consistent effect on helmet efficacy, while the masses and radii of helmets contained confounding variables that made it difficult to predict the effectiveness of attenuating the head accelerations

Comparative Analysis of Impact Attenuation Properties from Soccer Headgear

Athletes suffering from long-term neurocognitive deficiency due to subconcussive impacts is a major concern for football and soccer players today. Football players wear helmets that can help reduce injury risks like skull fractures, and these helmets must meet standard criteria that determinines how well a functional helmet should reduce accelerations of the player’s head. Currently no standard exists for testing soccer headgear despite studies demonstrating soccer players experience similar magnitudes of impacts. In this study, a modal impact hammer was used in conjunction with a Hybrid III 50th percentile test dummy head to simulate impacts experienced by soccer players to quantify the effectiveness of headgear in attenuating head acceleration due to direct impacts. The study found one device to be functional, and able to reduce the translational acceleration for an average hit experienced by a soccer player by 20%. Devices need to be developed and common testing standards need to be established to allow for a more widespread implementation of similar devices to protect players from short and long-term injuries due to impacts