Hood development of internal structures in vehicles is an
important alternative to minimize the injuries to pedestrians in
case of a running over accident. In fact, according to Berg et al
(2002), about 17% of head impacts occur on the hood. Moreover,
according to Farooq and Schuster (2003), 62% of fatal injuries are
caused by head trauma.
This study focuses on evaluating the influence of free space
between the hood and rigid components, considering cut out hood
inner panel design, which is one of the geometries most commonly
used by auto industries. The major advantage of this structure is
its weight, leading, however, to small stiffness.
Injuries to the head of a pedestrian is measured through a
finite element model, in accordance with the European Committee for
improvement in vehicle safety. There are several ways to measure
the damage caused by the deceleration of the head. Here, the
measure HIC (Head Injury Criteria), created by the NHTSA (National
Highway Transport Safety Association) in 1971, is chosen, since it
is still the most used and recommended method in the
literature.
Finally, the analyses of the numerical results lead to practical
suggestions for auto industry.