The Naval Biodynamics Laboratory (NBDL) in New Orleans has conducted an extensive research program over the past years to determine the head-neck response of volunteer subjects to impact acceleration. These subjects were exposed to impacts in frontal, lateral and oblique directions. An analysis of a limited number of frontal and lateral tests from a test series conducted in the late seventies with two subjects showed that the observed head-neck dynamics can be described by means of a relatively simple 2-pivot analog system (1,2)* .

The present study extends this analysis to a more recent NBDL test program with 16 human subjects. The database consists of 119 frontal, 72 lateral and 62 oblique tests. The research methodology used for this analysis includes a detailed description of three-dimensional kinematics as well as load calculations near T1 and the occipital condyles. A description of this research methodology and a summary of the major test results will be presented. Special attention is given to the influence of impact severity and impact direction on the head-neck dynamics. It will be shown that a similar analog system as proposed earlier for frontal and lateral impacts, is suitable for all impact directions. Geometrical properties of this analog have been determined by means of newly developed numerical techniques rather than through the graphical techniques that were used earlier. findings of this analysis will be discussed in view of future omni-directional mechanical neck developments.