Development and Testing of a Prototype Pregnant Abdomen for the Small-Female Hybrid III ATD

A new prototype pregnant abdomen for the Hybrid III small-female ATD is being developed and has been evaluated in a series of component and whole-dummy tests. The new abdomen uses a fluid-filled silicone-rubber bladder to represent the human uterus at 30-weeks gestation, and incorporates anthropometry based on measurements of pregnant women in an automotive driving posture. The response of the new pregnant abdomen to rigid-bar, belt, and close-proximity airbag loading closely matches the human cadaver response, which is thought to be representative to the response of the pregnant abdomen. In the current prototype, known as MAMA-2B (Maternal Anthropomorphic Measurement Apparatus, version 2B), the risk of adverse fetal outcome is determined by measuring the peak anterior pressure within the fluid-filled bladder. Peak internal bladder pressures measured in a series of sled-test simulations of frontal crashes of different severities and occupant-restraint conditions have been correlated to the likelihood of adverse fetal outcome based on risk curves developed from in-depth investigations of real-world crashes involving pregnant occupants. Compared to the original pregnant abdomen, the new prototype has improved geometry and improved impact response to a range of potential in-vehicle loading conditions, However, additional instrumentation development and more rigorous testing are needed before the MAMA-2B can be confidently used to assess restraint system performance with regard to reducing the likelihood of adverse fetal outcome in motor-vehicle crashes.