Biomechanics research and volunteer testing has quantified and described injury mechanisms and thresholds for many types of injuries throughout the human body. However, little if any mechanism or threshold quantification exists for minor injuries or injuries that can only be diagnosed based upon a patient’s complaints of pain. A method commonly used to evaluate the effects of a minor automotive accident on the occupants of the vehicles involved is to compare the forces and accelerations the occupants were exposed to in the accident with the forces and accelerations experienced when performing a variety of daily living type activities, or while riding amusement park rides. There are few studies that have been conducted using human volunteers to measure their linear head accelerations during various activities of daily living. Presently, no studies have been found that measure the angular acceleration of the head during minor accidents or during activities of daily living. There are, however, studies that attempt to associate various head, neck, and brain injuries to these minor accidents with or without a head impact.

The present work is being conducted to quantify the linear and angular head accelerations humans experience during various activities of daily living. This work is being performed in order to, among other things, compare these accelerations to those experienced by an occupant involved in a minor vehicular accident. The work presented here briefly details the design of a head mounted accelerometer array fixture, derivation of the system of equations for this array, and quasi-planar validation of the fixture and calculation methodology. Planar validation testing indicates that up to an event duration of 0.200 seconds the angular acceleration and linear acceleration at the center of gravity can be determined by measuring the triaxial acceleration at three different locations on the head and then applying the relative velocity and relative acceleration equations. Events with durations longer than 0.200 seconds require the direct measurement of angular velocity on each coordinate axis in order to determine the head angular accelerations and the head center of gravity linear accelerations.