Full-scale vertical drop test and numerical simulation of a crashworthy helicopter seat/occupant system

A full-scale vertical drop test of a crashworthy helicopter seat/occupant system was performed to evaluate the energy-absorption capability of a new-type crashworthy seat, and to study its influence under impact conditions on the occupant responses and human tolerance. In order to gain a better understanding of the physics behind the impact, a numerical simulation of the crashworthy seat structure was carried out and the simulation results were compared with the test data. In the numerical simulation, a full-scale three-dimensional multi-rigid body model of the seat/occupant structure was developed using a commercial code, Mathematical Dynamic Model (MADYMO), associated with non-linear finite element code (LS-DYNA). Emphasis of the numerical simulation was placed on predicting the dynamic response of seat/occupant system, including the occupant motion that may lead to injuries due to intensive whipping of human body, the acceleration-time histories and the energy-absorbing behaviour of the inversion tubes and seat pan.