A Human Body Model Study on Restraints for Side-Facing Occupants in Frontal Crashes of an Automated Vehicle

This study is to investigate kinematics and responses of side-facing seated occupants in frontal crashes of an automated minivan using Global Human Body Models Consortium (GHBMC) simplified occupant models (50th%ile male and 5th%ile female), and to develop new restraint concepts to protect the occupants. The latest GHBMC M50-OS and F05-OS models (version 2.1) were further validated with the Postmortem Human Subject (PMHS) side sled tests [Cavanaugh 1990] and the PMHS far-side sled tests [Formen 2013], with detailed correlations of the kinematics and the injury measures. Robustness and biofidelity of the GHBMC human models, especially for the pelvis and knee body regions, were further improved. Using the improved M50-OS and F05-OS models, we evaluated the body kinematics and injury measures of the side-facing seated occupants in frontal crashes at severities ranging from 15 mph to 35 mph. Three restraint conditions were studied: 1) no restraint; 2) lap belt only; 3) lap belt and conceptual inflatable device. An additional parametric study on the restraint design parameters of the #3 restraint concept was performed to “optimize” the restraint performance toward reducing the occupant injury risks. The kinematics and injury patterns differed significantly with the occupant size, crash severity, and restraint conditions. The unrestrained and lap belt only conditions did not prevent the increase of injury risks at the higher crash severity. The lap belt and “optimized” conceptual inflatable device reduced greatly the occupant injury risks compared to the other restraint conditions. This study demonstrated challenges and opportunities in the restraint designs for protecting the side-facing occupants in frontal crashes of automated vehicles.