Internal Fluid Characteristics of Cylinder-Type Air-Safety Cushion as a Function of Dummy-Drop Height

In this study, we analyzed the relationship between the internal pressure rise of a cylinder-type air-safety cushion and the drop height of a dummy. The volume change in relation to the increase in the internal pressure was evaluated using the ideal gas equation of state. A prototype cylinder-type air cushion with dimensions of 3.7 × 3.7 × 1.7 m3 was used in the experiments. A dummy weighing 75 kg was dropped from heights of 8, 12, and 16 m, and the internal pressure of the cylinder and the resulting volume reduction were analyzed. The internal pressure of the air safety mat increased by 7.3%~10.7%, while its volume decreased by 4.2%~10.1%. The results of this study can be applied as research data to evaluate the acceleration value for the head injury criterion for air safety cushions.