The objective of this research was to develop a pregnancy insert for the Hybrid III female dummy which would allow evaluation of various restraint conditions on energy transmission to the fetus. The pregnancy insert includes a urethane “abdomen-uterus" surrounding an ellipsoidal “amniotic fluid” gel and simulated 28-32 week “fetus,“ and fits into a 5th percentile Hybrid III female dummy. The “fetus” is instrumented with accelerometers in the head and thorax. A load-measuring reaction plate records force on the abdomen. Thirty-nine crash tests were run in the driver and right front passenger position on a Hyge sled under eleven different belt restraint and airbag conditions at 10-25 mph (4.5-112 m/s). in the first series, feta! and maternal responses for recommended lap-shoulder belt placement were compared to improper placement of the lap or shoulder belt. In the second series, several driver airbag restraint conditions were studied.

Placement of the lap belt over the "uterus" or shoulder belt behind the back resulted in more than a three-fold increase in force transmission through the abdomen in comparison to proper belt placement. increasing the speed of crash resulted in greater acceleration of the "fetus." Airbag deployment with or without belt use resulted in relatively low force transmission to the “uterus,” but “out-of-position” airbag deployments resulted in high fetal acceleration. The fetal responses are assessed in terms of abdominal force, acceleration of the fetal head and chest, relative acceleration between the fetus and mother, and relative acceleration between the fetal head and chest. The new pregnant dummy demonstrates higher responses in all conditions of improper placement of the lap or shoulder belt. Proper use of the lap-shoulder belt and airbag appears to reduce the likelihood of crash injury to the unborn baby and mother.