Automated Vehicle Occupant Kinematics Phase 1: Upright and Reclined Frontal Impacts with Male PMHS

Abstract

This study gathered biomechanical response and injury data from male post-mortem human subjects (PMHS) to provide data for establishing performance targets for anthropomorphic test device (ATD) testing and human body model simulations in reclined and upright postures with belt-only restraint. Tests were conducted on a laboratory sled in a frontal impact condition at 32 and 50 km/h nominal delta V. At each test speed, three PMHS were tested at a nominal 25 ̊ recline posture and three at a 45 ̊ recline, for a total of 12 tests. Three tests were conducted at the 45 ̊, 50 km/h condition with a simulated knee bolster placed 100 mm from the pre-test knee position. Corridors were computed for key dependent measures, including head and pelvis excursion. Contrary to expectations, clear submarining was observed in only one 50 km/h, 25 ̊ test. All tests produced injury. Recline increased the frequency of injury, with greater increases in the number of injuries at the higher test speed. Rib fractures were common, with the number increasing with test speed and recline. No lumbar spine fractures were observed in the tests at 32 km/h, but an average of two lumbar vertebrae were fractured at 50 km/h and 25 ̊ and at least three were fractured in the tests at 50 km/h and 45 ̊. Adding a knee bolster 100 mm from the pre-test knee location in the 45 ̊, 50 km/h condition reduced the maximum AIS to 3 from 5 by reducing the mean number of rib fractures from 36 to 19, approximately the same number observed in the 45 ̊, 32 km/h test without the bolster. Lumbar spine fractures were observed only at the higher recline angle.