The Effects of Added Mass on the Dynamic Motions of the Head and Trunk During Running and Walking

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Abstract

The addition of mass to the head has applications from the design of football helmets to the placement of loads on head mounted displays. Determining the effects of mass placed on the head ensures that the design of these systems can be optimized to reduce the effects on the user and to reduce the change of injury occurring.

A testing protocol was developed to determine the effect of mass added to the head which causes changes to total mass, moment of inertia, and torque applied. This testing protocol asked subjects to walk and run on a treadmill with different helmets and masses attached to their heads which changed the moment of inertia and torque applied. Position, velocity, and acceleration sensors were attached to the head and trunk in order to determine how the positioning and dynamic motions of the head and trunk were affected.

The results showed that the addition of mass to the head had very little effect on the positioning and dynamic motions of the head and trunk and there was no correlation between mass, moment of inertia, or torque applied and the positioning and dynamic motions exhibited by the subjects.

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