Improvement of Robustness of Vehicle Crashworthiness Relative to the Impact Angle

Improving the robustness of vehicle crashworthiness in relation to the impact angle may be quite important in enhancing vehicle safety under actual driving conditions. This importance can also be inferred from the fact that almost all of the accidents classified as frontal crashes in real-world driving have an impact angle. The first step of this research was to make clear the differences between inline offset impacts and oblique offset impacts, focusing on the behavior of the vehicle. Based on the results obtained, a feasibility study for improving the robustness of vehicle crashworthiness relative to the impact angle in frontal collisions was carried out. In order to analyze vehicle behavior and examine ways of improving robustness, oblique offset car-to-car (CTC) impact tests were conducted and simulations were run using finite element (FE) models. The method of evaluating vehicle body strength that was reported by Kitagawa et al. [7] was utilized to process the data. It was confirmed that this method yields useful results and that it can also be applied to oblique offset impacts. The results of the behavior analysis showed that the load paths and vehicle dynamic behavior differed substantially between inline offset impacts and oblique offset impacts. It was also found that a larger impact angle caused the load paths and vehicle dynamic behavior to change and that such changes were factors that contributed to greater or lesser body deformation; the extent of influence of each factor was observed to change as a result of changes in the impact angle. As a result of the feasibility study, it was confirmed that modification of the load paths of the front-end structure may improve the robustness of vehicle crashworthiness in relation to the impact angle.