Statistical Dependance of Human Occupant Accelerations on Vehicle Impact Measures in Rear-End Impacts

Abstract

Interest in the mitigation of whiplash associated disorders (WAD) has increased over the last 10 years, and an increasing number of human subject rear-end collision tests have been conducted to assist in the understanding of WAD. Traditionally this testing has examined the effects of variations in occupant characteristics (age, height, gender, etc.), seat characteristics (geometrical and constitutive), and impact severity; however no controlled study has examined the singular effect of incremental velocity change increases on occupant kinematics. Moreover, while vehicle velocity change (Delta V) is typically employed as a singular measure of impact severity, it is of interest to examine whether this or other impact-related parameters, such as energy or acceleration, are also correlated with occupant kinematics. A series of 43 instrumented human subject rear-end impact tests were conducted to monitor the effects of increasing impact severity on occupant accelerations. Target vehicle Delta V, average vehicle acceleration, peak vehicle acceleration, and vehicle kinetic energy change were statistically evaluated for their influence on various occupant response parameters which have been suggested to be associated with WAD causation in prior literature. Significantly (p < .001) strong positive correlations were found between vehicle parameters and human occupant variables.