Numerical and experimental approach of various sectioned new concept of the crash-boxes to determine the reliability and crashworthiness of the vehicles during frontal impacts

Özet

Overview on vehicle collisions shows us a perspective to evaluate the impact behavior of the vehicles and occupant safety. To decrease the deformations of the vehicle body and occupant injuries, many products have been developed already. The mentioned safety measures can be defined via active and passive security systems. This study is about, passive safety systems used naming “the crash-box” for vehicles during accidents, are investigated experimentally to reduce the shock effects of the frontal impacts. For crash-boxes square, circular or other standard closed sections are preferred regularly due to ease of the production. For this research, open section crash-boxes are studied. Up to the manufacturing restrictions one of the designs in four, is preferred. The new concept of crash-box is, assembling the specimens in front of the chassis and just behind front bumper, instead of using it like regular crash-boxes. Cross-section type of w shape, steel, sheet-metal crash-boxes are manufactured as a shock absorber unit. Height of 2.88m drop test setup was used for the experiments. Considering the limitations of the test setup, one eighth of a real accident scenario for a 1200kg vehicle can be processed with this experimental system. The impact tests are handled with 150kg drop weight and one crash-box unit as an accepted collision scale. To understand the most appropriate thickness for the absorbers is decided between 2mm, 1.5mm, 1mm and 0.8mm thick samples. Finally, 1mm thick St37 w shape crosssectional sheet metal crash-box is strong enough to absorb the impact energy of the frontal collisions.