The intention of this study was to compare the head-neck kinematics between a Hybrid III dummy equipped with a standard neck, a Hybrid III dummy equipped with a RID neck, volunteers and Post Mortal Test Objects (PMTOs) under similar rear end impact conditions by means of various sled tests. Two car seat types were used at impact velocities ranging from 6 to 15 km/h.The sled tests showed that movement of the head and neck of the standard Hybrid III dummy were quite different compared to volunteers and PMTOs. The RID neck seems to be better regarding biofidelity, but as several degrees of freedom are still missing compared to the human cervical spine, further improvements can still be made. The significant high degree of flexion between head and upper cervical spine during the PMTO test could not be observed for both dummy necks. Bending of the thoracic spine in volunteers and PMTOs appears to influence head and neck motion. This can not be reproduced by the rigid thoracic spine of the Hybrid III dummy. Another problem which arose during these tests was the insufficient modelling of the initial lordosis of the cervical spine in all dummy necks. (A)
Abstract