PMHS impact response in low and high-speed nearside impacts

Abstract

Lateral impact tests were performed using seven male post-mortem human subjects (whole, unembalmed cadavers) to further characterize the response of the body, and in particular the force-deflection response of the lower abdomen, to lateral impact. All tests were performed using a dual-sled, side-impact test facility. A multi-segmented impactor was mounted on a sled that was pneumatically accelerated into a second, initially stationary sled on which a cadaver subject was seated facing perpendicular to the direction of impact. Sizes and heights of impactor segments were adjusted for each subject so that forces applied to different anatomic regions including thorax, abdomen, greater trochanter, iliac wing, and thigh could be independently measured on each cadaver. For all tests, the impactor contact surfaces were located in the same vertical plane except that the abdomen plate was offset 5.1 cm toward the subject. Each subject was first impacted on one side of the body using an initial impactor speed of 3 m/s. Following the five of these tests that did not result in injury, the contralateral side of the body was impacted at a speed of either 8 m/s or 10 m/s. The masses of the sleds and the force-deflection characteristics of the energy-absorbing material that acted as the interface between the sleds were set so that the velocity history of the impactor sled matched the average driver door velocity history produced in a series of side NCAP tests. Impactor padding was also selected so that average ATD pelvis and thorax responses from the same series of side NCAP tests were reproduced when the ATD used in these tests was impacted using the average door-velocity history. Results of these tests were used to develop force-deflection response targets for the abdomen, force history response targets for the pelvis (iliac wing and greater trochanter), the midthigh, and the thorax at each of the three impact velocities. Response targets for the lateral acceleration of the pelvis were also developed. Future work will compare side impact ATD responses to these response targets.