Numerical approximation of the scaled frontal impact scenario of a vehicle to optimize the crash-boxes validated via experiments to reduce the collision effects

Accidents happen in various ways in everyday use in transportation vehicles. Although extensive numbers of precaution methods are applied for prevention, the accidents are still inevitable. Especially in the field of vehicle design, many safety techniques are being developed to prohibit accidents and to reduce the loss of life and vehicle damages in the event of an accident. These security measures can be grouped under two headings as active and passive security systems. In this study, passive safety system which comprises material changes and structural improvements on the vehicle in the event of an scaled accident scenario, are examined in order to reduce as much as possible the adverse effects of the collision. Circle, hexagonal, square and the new W shaped cross-sectional steel sheet-metal crash-boxes are designed to absorb the shock waves and deformation energy between the chassis and the bumper of the vehicle as a new perspective focusing on the crash-boxes. For the frontal impact scenario, 2.88m high drop test setup was used. The designs are optimized via using thickness differences of the uniform material and shape. The deformation amounts and shock accelerations are keys to define the absorbed shock energy during the impact process. All these procedures carried out by the explicit finite element simulations also. Finally, 1mm thick St37 w shaped cross-sectional sheet metal crash-box perceived to absorb the enough amount of impact energy of the scaled version of frontal collisions with a speed around 25km/h. Keywords: Vehicle Crashworthiness, Crash-box and Safety, Energy Absorption, Impact Simulation.