The low-speed crash is used for type classification RCAR/AZT. In this scenario, the vehicle hits a 10° inclined barrier at 15 km/h. The vehicle’s front covers 40% of the barrier, representing minor accidents. Crash elements in the front help limit damage, protecting components behind them to allow for more cost-effective repairs. This scenario is used as an insurance case to determine maintenance costs.
The crash box of the Honda Accord model (Source: LS-DYNA model – National Highway Traffic Safety Administration NHTSA) is made of two sheets of metal welded together. Its purpose is to absorb all the kinetic energy for this scenario. The energy to be absorbed depends on the vehicle mass and initial speed. Geometrical patterns (e.g. beads and indentations) can be applied to initiate robust folding and buckling. The goal is to keep the force level between components low enough to prevent further damage. So-called trigger mechanisms, usually changes in shape, surface, or corners, can create an imperfection. Slight pre-damages can also be used. Besides energy absorption, requirements for towing load cases must be considered.
The image shows a possible inlay structure (green) involved in deformation. The internal bracing of the three-dimensional frame structure is automatically generated according to the loads. The outer shell is designed to be very flexible, and energy absorption occurs through combined deformation of the shell and inlay structure. The goal of the optimization process is to minimize contact force, with a permissible displacement of the impactor not exceeding 110 mm.
