Modeling of a deformable manikin neck for multibody dynamic simulation

The Articulated Total Body (ATB) is a rigid body dynamics computer model of the human body used at the Armstrong Laboratory (AL). The model is used to predict the kinetic response of the human body in different dynamic environments, such as aircraft pilot ejections, sled tests, etc. In order to predict the response accurately, however, a rigid body model may not be sufficient. This is particularly true for the more flexible segments such as the neck, and for cases where local segment vibrations occur. In this study, a deformable body dynamics option of the ATB is developed, which incorporates linear deformation of individual segments in the ATB model. The displacements due to deformation are determined using finite element modal analysis. The study concentrates on the modeling of manikin necks which have shown large deformation in certain environments. The Hybrid III manikin neck finite element model and modal solution are presented. Modal analysis results are incorporated into the ATB model. Selected parameters for quasi-static Hybrid III neck and several head-neck dynamic simulations are compared with the experimental results, where available. It is shown that the new model simulation results have excellent agreement with the experimental results, particularly when compared with the rigid model.