A Comparison of the Hybrid III and BioRID II Dummies in Low-Severity, Rear-Impact Sled Tests

A BioRID II dummy and a Hybrid III dummy, each representative of a midsize adult male, were tested side-by-side in simulated rear-impact sled tests. In all tests the dummies were restrained by 3-point belt systems. The results of 4 test sets conducted at a nominal change in velocity (ΔV) of 16 km/hr are presented and discussed. In three of the test sets, bucket seats were used. The head restraints were placed in the up-position in two of the three test sets and in the down-position in the third set of tests. In the fourth test set, rigid seats without any head restraints were used. While analyzing the BioRID II data, the presence of an axial neck load acting on the head, which bypassed the upper neck load transducer, was discovered in all the reported tests. The implication of this observation is that the axial force and all the moments measured by the BioRID II upper neck load transducer could be erroneous. A second concern with the BioRID II data was the high frequency noise observed, especially on the T1 acceleration response which is used in the NIC calculation. The 18 Hz filter used to process the T1 acceleration data for the NIC calculation attenuated the peak NIC values by 15% as compared to the SAE 180 filtered values. The unmeasured neck loads and high-frequency noise issues need to be resolved before additional BioRID II testing is done. A third concern with the BioRID II is the initial position of its head in the automotive seating posture. It is higher and more forward than that of the 50^th percentile adult male.