Designing a Mechanical Linkage Capable of Decreasing Force Transfer from the Facemask to the Protective Helmet when Loading Occurs

摘要

IntroductionSports that involve extensive personal contact have a high incidence of injury. The introduction of regulations mandating the use of personal protective equipment in these sports is the most common injury control strategy (Marshall et al., 2002). Negligible attention has been paid to the mechanical linkage between the facemask and helmet as a means of reducing force transfer from the facemask, through the helmet, and to the head and or neck of the athlete.MethodsA novel prototype mechanical linkage of reasonable simplicity that provides 360° of freedom in motion capable of decreasing force transfer from the facemask to the protective helmet when loading occurs was designed. Force was applied at three angulations to the long axis of the a control and prototype mechanical linkage, under both compressive and tensile force, generating six experimental groups: Tension at 0°, Tension at 45°, Tension at 90°, Compression at 0°, Compression at 45°, and Compression at 90°. For each experimental group, the force transferred from the facemask connector to the helmet connector and deflection of the mechanical linkage at failure was evaluated.ResultsFor each condition measured under both compressive and tensile force; maximum force transfer within the limits of the theoretical range of motion, force transfer at failure and linkage deflection at failure statistically significant differences between the control and prototype groups were observed with a t test for independent samples with unequal variance (p u3c 0.001), α = 0.05.ConclusionWhen compared to currently available designs, the prototype mechanical linkage designed and tested as part of this project is of reasonable simplicity, displays increased flexibility and provides 360° of freedom in motion. Under compressive and tensile forces, force transfer from the facemask component to helmet component was decreased significantly.