Perpustakaan Digital ITB

Indonesia's projected population growth drives a rising demand for passenger cars, increasing the risk of traffic accidents. Frontal collision is among the most frequent and severe crash case, coinciding with the rising trend of severely injured casualties. Restraint systems such as airbags and seat belts consistently reduce the risk of severe injury. However, to protect occupant during a crash, studies have shown that airbag protection depends strongly on its inflation characteristics. This undergraduate thesis presents a parametric study of airbag pressure, conducted by varying the inflator mass flow rate, to analyze its effect on the injury levels and potential of the driver's head, neck, thorax, and femur. A simplified finite element model of a 2020 Nissan Rogue with a driver’s side Hybrid III 50th percentile male dummy was simulated in LS-DYNA following the NCAP full-frontal rigid barrier configuration at 56 km/h. The mass flow rate was varied from 1 to 4 kg/s, with a noairbag configuration as reference. HIC15, neck axial force, neck bending moment, 3 ms thoracic acceleration, thoracic deflection, and femur axial force values were extracted, and the model was verified through energy balance and validated against experimental test data. The results showed that the mass flow rate has a significant, non-monotonic influence on driver injury. At 1 kg/s the airbag remained only partially inflated at head contact, producing a punchout effect and a higher HIC15 than the no-airbag case, while neck and thoracic responses varied with airbag-to-driver timing. Increasing the rate generally improved protection, with 4 kg/s giving the most favorable overall injury mitigation. Whereas earlier studies varied a single parameter or limited body regions, this work evaluates head, neck, thorax, and femur together across inflation rates, contributing inflation-rate-specific guidance for restraint-system development and recommendation toward safer driver protection.