Technical Paper
A Finite Element and Multi-body Model of the Pregnant Female Occupant for the Analysis of Restraint Effectiveness
2003-03-03
2003-01-0157
A finite element model of a 7-month pregnant uterus was created and integrated into a multi-body human model. The uterine model contains 11,632 elements and 16,335 nodes. The pregnant occupant model was validated using known abdominal response corridors. Unrestrained, 3-pt belt, and 3-pt belt plus airbag tests were simulated at speeds ranging from 13 kph to 55 kph. Peak uterine strain was found to be a good predictor of fetal outcome (R2= 0.85). The strain in the uterine wall exceeded 60%, sufficient to cause placental abruption, in simulations of no restraint at 35 kph and 3-pt belt tests at 45 kph and 55kph. These tests represent a greater than 75% risk of adverse fetal outcome. For matched tests at 35 kph, strains of 60.8% for the unrestrained occupant, 52.6% strain for the 3-pt seatbelt and only 33.0% strain for the 3-pt seatbelt and airbag combination were recorded.
