Pulse Sensitivity of a Child Restraint System, Near-Side Impact Fixture

The National Highway Traffic Safety Administration (NHTSA) has utilized a two part sled fixture to evaluate a near side test protocol for child restraint systems (CRS). The test was designed to impact the CRS with a fixed door at nearly 20 mph. This paper examines the affects of various fixture parameters on the acceleration and velocity profiles of the two part system during the impact event. It was determined that the kinematic time histories are sensitive to crush energy dissipation (as evaluated with variance in aluminum honeycomb volume) and fixture weight. It was also determined that payload weight, impact speed, and impact plane alignment have a small effect on the acceleration and velocity profiles. Even though the kinematics of the secondary carriage was small with the change in the impact plane alignment, it was determined that the CRS utilized in the standard test would have a 23% reduction in impact energy when compared to the CRS with the impact planes aligned.