Although extensive modeling efforts have been made in the past decades topredict occupant/pedestrian knee-thigh-hip (KTH) injuries, prediction forthe injuries at the tissue level for various loading conditions observed in automotive crashes is still challenging. This study develops model-based tissue injury criteria and a tool to predict occupant KTH injuries subject to different postures and loading rates. An effective plastic strain based injury criterion with a defined universal threshold was developed for identification of the potential injury locations in the KTH body region. The published cadaver KTH low-rate impact tests at three postures of neutral, adduction, and flexion by UMTRI (University of Michigan Transportation Research Institute) have been simulated with the Takata 50th% male human model. Using the defined criteria, the model predicted the hip-bone and hip-joint fractures for the three postures, were well correlated to those observed from the tests. The KTH impacts were also simulated at two loading rates. The simulation results indicated a possible mode shift of the impactrate-associated injury with assumptions of viscous effects on hip-joint. A high rate impact more likely generates a fracture at the femur shaft; and the impact at a lower rate more likely fractures the hip-joint. The validated KTH injury criteria and tool were thus applied for accident reconstruction of two vehicle crash cases (full frontal and offset frontal impacts) selected from the NASS/CDS & CIREN database, which caused occupant KTH injuries at AIS 2-3 scale. The simulations match the injury outcomes of thereported field observations. The full text of this paper may be found at:http://www-nrd.nhtsa.dot.gov/pdf/esv/esv21/09-0334.pdf For the covering abstract see ITRD E145407.
Samenvatting