Analysis of child dummy responses and CRS performance in frontal NCAP tests

The new car assessment program (NCAP) conducted 95 frontal crashes with child dummies in child restraint systems (CRS) in the rear seat. In addition to the two mid-size male dummies in the front seat, there were one or two child dummies in the rear seat area. The child dummies were (1) 12-month-old, (2) 3-year-old, and (3) 6-year-old. The child dummies were restrained in a CRS or a booster. This research focused on comparing the response of the child dummies with the adult dummy. The study examined the dynamic readings of the head acceleration, chest acceleration, chest deflection, and upper neck loading. In terms of the customary injury assessment reference values (IARVs) for the adult and child dummies, the adult dummy had an easier time going under the IARVs than the child dummies. The passing rate for the adult was almost 100% while the passing rate was 60 - 70% for the child dummies. In short, the different dummy sizes in their respective seating location do not show the same relative level of protection as measured by body motion and instrumentation inside the dummy occupant. The 3-year-old and 6-year-old child dummies show relatively elevated head response because their heads are not restrained in the sense that the adult’s head is cushioned by the airbag. Some device or concept is needed to reduce the rotational motion of the head for the forward-facing child. The child dummies do not take advantage of the ride down (connecting the occupant to the initial crushing of the vehicle structure to slow down the occupant) as capably as the adult dummy. Some device or concept - such as the pre-tensioner for the adult in the front seat - is needed to reduce the free motion of the forward-facing child. The motion and response of the 6-year old child dummy appear to vary more than the other crash test dummies.