Biofidelity of an original and modified sidiis upper extremity matched cadaver and dummy compression tests

Approximately 8,000 automobile occupants are killed and 24,000 seriously injured each year in automotive side impact collisions. In order to accurately predict injury of human occupants, the response of automotive side impact anthropometric test dummies must be as biofidelic as possible. The upper arm serves as a load path to the thorax, and the response characteristics of the upper arm can influence the thoracic response in side impact test dummies. Therefore, the purpose of the study is to characterize the compressive response of male and female humeri with all soft tissue attached, an original SIDIIs arm, and a modified SID-IIs arm to evaluate the biofidelity of the side impact dummy arm. A series of compression tests were performed at two dynamic rates, 2.34 m/s and 3.81 m/s, on a total of eight male and female humeri with all soft tissues attached. Matched compression tests were preformed on the original SID-IIs and a modified SID-IIs upper arm segment using a drop tower. The impact direction for all tests was from lateral to medial in order to simulate an automotive side impact collision. In order to correct for the loss in the cadaver arm tissue thickness resulting from the horizontal test orientation, the upper arms of 35 male and 35 female volunteers were measured. The results show that for both rates the modified Sid-IIs arm force vs. compression response was more representative of the cadaver humeri force vs. compression responses than the original Sid-IIs arm. The more realistic response characteristics of the modified Sid-IIs arm could improve the biofidelity of the overall thoracic response in side impact anthropometric test dummies.