Effect of Trigger Variation on Frontal Rail Crash Performance

The frontal rail is one of the most important components of a vehicle in determining crash performance, especially for a body on frame vehicle. Prior research [1] has shown that the frontal rail absorbs a significant amount of impact energy in a crash condition. In order to optimize crash performance, a component level sensitivity study was conducted to determine the effect different types of triggers would have on the performance of the frontal rail. The objective of this study is to determine the sensitivity of trigger size, trigger shape, and trigger orientation as well as to improve corresponding trigger modeling methodology by comparing crushed components to crushed CAE models. In this sensitivity study, the location of the triggers was held fixed, while the size, shape, and orientation were varied. The metric that will be used to compare the performance of these different trigger shapes is the overall stiffness of the frontal rail. This sensitivity study indicates that the trigger size has a more significant effect on the crush performance of a frontal rail than those of the trigger shape and trigger orientation. Of the trigger shapes studied, further analysis of Square #1 is recommended. A comparison of CAE simulations to component level tests show that by following a step-by-step process, one can achieve a good correlation.