The Effect Of Muscle Activation On The Dynamic Response Of The Head And Neck In Front Crash

The proportion of neck injuries is large and still on the rise in modern traffic accident according to related statistic. It's difficult to diagnose and cure the neck injury as its mechanism of injury is not clear enough, though neck injury is not fatal injury. FE models are not only can simulate volunteers test to restore occupant crash scene, but also have higher biological fidelity and repeatability than mechanical dummy in experiment. And the FE models are not strictly limited by the test risk and ethics. So, a FE dummy which has good biological fidelity can help understanding the mechanism of head-neck injuries more in-depth.This study was focusing on the development of a dummy FE model, which had accurate geometic information of human as well as the active response of neck muscles. A detailed analysis of how the muscle active force and how the dummy awareness affect the response of head-neck was done.Firstly, the research history and current situation was inviewed. The injury mechanism of neck, related FE modeling literatures as well as neck biomechanics were summarized as well. A FE model of a car was developed by using hypermesh. A simulation of the front impact of the car was carried out in LS-dyna and the reliability of the car was analyzed. The front impact model for driver restraint system of the coach was established. This model includes the driver seat, three-point safety belt and the floor. Basing on the Hybrid III dummy and the Head-Neck FE model, a mixed dummy which is suitable for front collision simulation analysis was established. The mixed dummy was then validated by reconstructing 15 g front impact experiment conducted by Ewing et al. The effect of the neck muscle active force and awareness on the head-neck response in low, medium and high speed front crash was studied. Dynamic response of the mixed dummy showed that neck active force can help reduce the kinetic parameters of the head and the strain of the neck biological tissue. The awareness of the mixed dummy was also. In other words, the injury risk of the head-neck was reduced because of the preloaded of neck muscle active force.In this paper, as the amplitude of the neck muscle response data in front collision is very limited. The neck muscle activation degree curve was estimated according to the response of the mixed dummy in this study. The future study will focus on the electromyography magnitude of neck muscles in front collision.