AN EXPERIMENTAL METHOD FOR MULTI-VARIABLE ANALYSIS OF VEHICLE SAFETY SYSTEMS AND APPLICATION TO FRONT SEATS REAR OCCUPANT INTERACTION IN REAR IMPACTS

摘要

This study presents a combined experimental-analytical method for test efficient, and cost effective, multi-variable analysis of safety system performance related to occupant injury potential analyzed over wide parameter ranges. Experimental techniques such as the "two-level factorial" method, in combination with sled-buck test set-ups (that match vehicle crash characteristics), are applied to demonstrate the technique for front seat performance as it relates to injury potential of the front occupant and rear seated children during rear impacts. The surrogate data from the above test method is combined into a "polynomial response function", such as HIC, which is developed as a function of the many variables, and allows for analytical "interpolation and extrapolation" at variable combinations not tested. A minimum of 4 test combinations are used to establish the "polynomial injury curves" as functions of two variables (i.e. impact severity and front occupant weight) for a given seat type. Inclusion of a third variable for evaluation of "seat strength effects" can be accomplished with a minimum of 8 test combinations for the factorial method. Both front adult and rear child interactions are studied. Three year-old H-III surrogates are used for the study of rear child passengers. Plots of test generated "polynomial" multi-variable HIC level curves for the front adult and rear child surrogates are presented as functions of impact severity and front occupant weight, for various seat types. Accident case head injury data of rear-seated children is used to verify the experimental-analytical method.