Research On Occupant Injury Prevention From Vehicle Impacts And Essential Elements Of Intelligent Airbag

In the area of automobile passive safety, over the past four decades, it is an essential problem for occupant to be protected from vehicle frontal impacts. The airbag is an effective protective device for occupants in vehicle crashes and is widely equipped in modern cars. However, its deployment can introduce new injury mechanisms while they save lives and decrease the severity of major injuries. This thesis described the present study to confirm the essential elements of an intelligent driver airbag system that will make the driver airbag adaptive to crash conditions. The performance of the intelligent driver airbag system will be improved to cover a wide range of occupant protections.1. A literature study was carried out for airbag and related topics, such as traffic accident injury epidemiology, crash biomechanics, mathematical and experimental models of the airbag systems. Furthermore, the driver airbag effectiveness and the airbag-induced injuries in frontal crash were analyzed and discussed.2. The thesis is based on a visiting study in Sweden to investigate the key parameters of intelligent airbag assembled into a passenger car, and the useful methods for the research of intelligent airbag essential elements using experiment and simulation technology were presented.3. Based on the literature study, a combined injury criteria index is used to evaluate the performance of various configurations of a driver airbag system. Parameter analysis was carried out for occupant collision response, including a sensitivity analysis of the models with selected variables. The result achieved from this study indicated that the correlations of airbag key parameters with injury responses is comparable with that of other similar researches.4. A new study idea that makes the occupant injury prevention research and CAD/CAE technology on an integrate mathematical model by means of feature theories and feature design technologies was brought, and it is maybe useful if we study automobile passive safety on a new view of point.The conclusions of this thesis included that what are the main factors of airbag-related injuries and the preventive measures, based on the research of the relationships between injury parameters, such as HIC, chest acceleration, neck force, neck moment, femur axial force etc, and impact speed, belt-use, occupant size (50th and 5th), sitting position and so on. The thesis evaluated whether the effectiveness of the airbag can be increased by making the airbag adaptive to the crash conditions, and points out that the size of the ventilation hole has the dominating influence on the performance of the airbag and is a key factor for intelligent airbag, multi-stage and lower-power inflator can cost effectively minimize the risk of injury to occupants from crashes. It is important for the researchers of intelligent airbag to keep the small size unbelted occupants in focus and it is necessary to study deeply the influence of airbag fold patterns and the extremity out-of-position situation. These topics are important in the study of occupant injury prevention and vehicle safety design.