University of Michigan, Ann Arbor, Transportation Research Institute
Abstract
Technical Report FinalImproved padding or other countermeasures in vehicle rear compartments could reduce the incidence
of head trauma for child occupants. However, knowledge of likely child head impact locations for a
range of crash scenarios is needed to determine which areas and structures should be padded and
where a side curtain should be deployed to protect child occupants. The objective of this study is to
use a scalable MAthematical DYnamic MOdels (MADYMO) model of a child occupant to estimate the
distributions of possible head impact locations as a function of crash type, vehicle interior
characteristics, and child size. To achieve this goal, a series of simulations using a scalable MADYMO
child-ATD model was conducted. The geometries of the second-row compartment from 5 vehicles
were recorded using a laser scanner to provide high-resolution data for assessing probable head
contact zones. Distributions of lateral and longitudinal delta V were calculated as a function of PDOF
using the NASS-CDS dataset to provide proper simulation conditions based on real-world crashes.
Simulations of crashes ranging from pure frontal to pure side impact (9 o’clock to 3 o’clock) with child
ATDs with and without backless boosters were conducted using UMTRI’s parametric child ATD model
in MADYMO, UMTRI's child ATD positioning procedure, and UMTRI's automated belt-fit and crash
simulation system. The simulation results were used to create a model of the spatial distribution of
head trajectories based on child body size and crash direction. By combining the head motion model
and the vehicle second-row geometry models, the likely head contact zones with respect to interior
components were identified. The findings of this study provide a reference for future vehicle rear
compartment design to reduce head injuries for older children.National Highway Traffic Safety Administrationhttps://deepblue.lib.umich.edu/bitstream/2027.42/154006/1/UMTRI-2012-20.pd