Optimizing Occupant Restraint Systems for Tactical Vehicles in Frontal Crashes

The objective of this study was to optimize the occupant restraint systems for a light tactical vehicle in frontal crashes. A combination of sled testing and computational modeling were performed to find the optimal seatbelt and airbag designs for protecting occupants represented by three size of ATDs and two military gear configurations. This study started with 20 sled frontal crash tests to setup the baseline performance of existing seatbelts, which have been presented previously; followed by parametric computational simulations to find the best combinations of seatbelt and airbag designs for different sizes of ATDs and military gear configurations involving both driver and passengers. Then 12 sled tests were conducted with the simulation-recommended restraint designs. The test results were further used to validate the models. Another series of computational simulations and 4 sled tests were performed to fine-tune the optimal restraint design solutions. The sled tests with the optimized seatbelt and airbag designs provided significant improvement of occupant protection from the baseline tests in terms of the head, neck, chest, and lower extremity injury measures. Using a baseline seatbelt without an airbag, the ATD tended to contact the steering wheel or the instrument panel, or sustained a significant head whipping motion inducing large head and neck injury measures. By adding the airbag and reducing the load limit in the seatbelt, the injury measures were improved significantly. This study demonstrated the benefit of adding a properly designed airbag and advanced seatbelt to improve the occupant protection in frontal crashes under an environment representing a light tactical vehicle.