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Car accidents have become the world's threatened harm humans a big nuisance. Accident not only caused huge casualties, and gave the world bring huge economic losses. In all types of vehicle accidents, the body is most commonly seen in the head and neck injury site, which in the car's rear-end collisions are particularly common. In the rear-end collision, the neck injury as high as 77.1%, and most of the accidents are rear-end collisions at low speeds (less than 25km / h) cases occurred. Thus, through the neck injury research, to guide automobile structural safety design to prevent low-speed rear-end collision caused neck injury, thus reducing or even eliminating the crew neck injury and other types of damage, with obvious economic and social significance. In this paper, a virtual computer simulation as the main means of head and neck in a rear-end collision in the dynamic response were studied: using multi-body rear-end crash dummy model BioRID Ⅱ, in MADYMO multibody dynamics software platform built on rear-end collision Crew neck dynamics analysis model. Model includes bodywork and seat multi-body model, the hybrid model of three-point seat belts, as well as multi-body occupant dummy BioRID Ⅱ model. Based on the established model, by adjusting the parameters of the backrest angle, position and angle of the headrest, backrest contact stiffness distribution, adjusting the rotation angle of the yield strength and stiffness characteristics of the seat parameters on the dynamic response of the neck. Model output parameters include acceleration of the head and T1, the relative rotational angle of the adjacent cervical vertebrae, the neck of the shear force, axial force and bending moment. NIC with neck injury criteria to evaluate the value and the Nkm values ??and evaluation of the risk of neck injury car seat neck injury protection performance levels. The results show that the seat on the rear-end collision characteristic parameters of the dynamic response of the neck and neck injury has an important impact. The greater the inclination of the backrest, the backrest of the trunk and the lower point of contact, the head and the greater the distance between the headrest, the higher the likelihood of neck injury; headrest is high and close to the head, and appropriate increase head angle, can provide effective support for the head, the neck helps reduce damage; large back on the small stiffness distribution also advantageously reduce neck injuries; have greater yield strength and smaller stiffness the variability of the adjuster, the head and the chest can be reduced differences in relative movement, reducing the damage to the neck. Based on the above analysis, the occupant restraint system can be achieved by improved design, as well as by preventing rear-end collision protection system designed to reduce the incidence of rear-end collisions and reduce rear-end collision occurred when the crew damage.
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