The inertial responses of five seated unembalmed midsize cadavers to sub-injury knee impact loading were characterized and compared to the inertial responses of the Hybrid III midsize male and THORNT ATDs collected under similar knee loading conditions. All impacts were performed using a 275- kg padded impactor to symmetrically load the left and right knees at velocities of either 1.2 or 3.5 m/s. At both knee impact velocities, the Hybrid III and THOR-NT produced peak knee impact forces that were substantially higher than those of the cadaver. At the 1.2 m/s impact velocity, the peak knee impact forces produced by the cadavers varied from 0.9 to 1.0 kN while the peak knee impact forces produced by the THOR and Hybrid III were 1.4 and 1.6 kN, respectively. The two cadavers tested at the 3.5 m/s impact velocity produced peak applied forces of 3.5 and 3.8 kN, while the THOR and Hybrid III produced peak applied forces averaging 5.5 and 6.1 kN, respectively.

For both knee impact velocities, femur and pelvis accelerations produced by both ATDs and the cadavers were similar in magnitude. However, peaks in cadaver femur and pelvis accelerations occurred substantially earlier than peaks in cadaver knee impact force, while peak Hybrid III and THOR femur and pelvis accelerations occurred at the time of peak force. These differences are most likely due to loosely coupled mass in the cadaver that is not represented in either ATD.