CABIN GEOMETRY FACTORS AND FAR-SIDE OCCUPANT INJURIES: A BIOMECHANICAL CORRELATION STUDY

The primary source of injury to far-side occupants in side impacts is contact with the interior of the cabin environment, while the extent to which different environmental geometry factors and restraint system parameters in the cabin are associated with far-side occupant injury remains unclear. To address variations in far-side occupant injury patterns induced by vehicle structural layout parameters, this study employed the Stochastic Finite Element Method (SFEM) to conduct random sampling of four cabin environmental factors. The resulting sample injury data were subsequently analyzed within a Grey Relation Analysis (GRA) framework. This methodology enabled the quantitative evaluation of the correlations between the specified cabin environmental factors and far-side occupant injury metrics through the calculation of grey relation coefficients. The results show that in pure lateral impact, the most critical environmental factor influencing far-side occupant injury was identified as the center console position (including console height and lateral distance to the occupant). Specifically, head acceleration, head offset, and thoracic spine acceleration had the strongest correlations with console height, with relation coefficients of 0.78 or more, while chest and abdominal deflection had the highest relation coefficients with console-to-occupant distance, at 0.8 and 0.82, respectively. In oblique impact, however, various environmental factors collectively influenced occupants, with an average distribution of relation coefficients between the factors and injury indicators. There was a relative decrease in the correlation between center console position and injuries to all parts of the occupant, while the correlation between belt limit peak force and thoracic and abdominal injuries increased, especially the chest and abdominal deflection and the acceleration of the lower thoracic portion of T8 and T12. This study provides insights into the biomechanical injury mechanisms of the head, chest, and abdomen in far-side occupants, informing protective strategy enhancements.