Establishing Initial Equilibrium Positions for Crash Victim Simulators

In the utilization of crash victim computer simulations, the task of establishing the initial equilibrium position of the seated occupant or anthropomorphic dummy is usually tedious. This paper presents the derivation of the system of nonlinear equations required for obtaining equilibrium, the computer code for the solution of these equations, and a number of sample solutions for various vehicle interior geometries using a typical seat force-deflection curve and occupant size. A sensitivity study that shows the effect of deviations from equilibrium on results obtained from simulations utilizing the MVMA 2-D crash victim simulation program (1)* is also presented. The computer code was tested in conjunction with MVMA 2-D simulations and was found to be advantageous as compared to manual methods, in terms of establishing standardized procedures and saving time.