Vehicle Front Structure in Consideration of Compatibility

A structure which effectively improves compatibility in a vehicle-to-vehicle frontal impact has been considered focusing on sub-frame structure that disperses applied force with multiple load paths. Evolved sub-frame structure has been studied by CAE with RADIOSS to search the possibility to reduce aggressivity and to improve self-protection at the same time.

Vehicle models used for this compatibility study were a large saloon car with sub-frame and a small family car without sub-frame. The large saloon car had three different front structures: original, forward-extended sub-frame, and original with 25%-stiffness reduced structures. The types of collision contained four different crash modes in a combination of lateral overlap rate difference and side member height difference. With these three different structures in four different crash modes, crash simulations were conducted to evaluate aggressivity and self-protection based on front structure and compartment deformations, energy absorption amount, and Average Height of Force (AHOF).

As a result, it was found that the front structure with forward-extended sub-frame improved both aggressivity and self-protection by preventing override effect through structural interaction enhancement.