Experimental and Numerical Studies of Crash Trigger Sensitivity in Frontal Impact

Advanced High Strength Steels (AHSS) along with innovative design and manufacturing processes are effective ways to improve crash energy management. Crash trigger hole is another technology which can been used on front rails for controlling crash buckling mode, avoiding crash mode instability and minimizing variations in crash mode due to imperfections in materials, part geometry, manufacturing, and assembly processes etc. In this study, prototyped crash columns with different trigger hole shapes, sizes and locations were physically tested in frontal crash impact tests. A corresponding crash computer simulation model was then created to perform the correlation study. The testing data, such as crash force-displacement curves and dynamic crash modes, were used to verify the FEA crash model and to study the trigger sensitivity and effects on front rail crash performance. The correlation between the physical tests and FEA prediction using non-linear dynamic software (LS-DYNA) was conducted, and reasonable agreement was achieved. The test results and the correlated FEA model can be used to provide guidelines for an optimal trigger design in future front rail development.