Assessment of potential forearm fracture due to driver air bag deployment is examined through a series of static air bag deployments with a specially instrumented Hybrid III dummy. The objective of this study was to determine the feasibility of measuring accelerations and bending moments on the Hybrid III dummy forearm as a potential injury index for arm fracture. Study of the National Accident Sampling System (NASS) data has shown that in isolated circumstances, an air bag deployment can cause lower arm fractures while the driver is making a turn. To examine this phenomenon, the Hybrid III dummy was instrumented with accelerometers and strain gages to allow measurement of the accelerations and moments on the right arm. The testing indicated that measurement of meaningful accelerations and bending moments was feasible using the instrumented dummy arm. Wide differences in peak accelerations and bending moments were associated with air bag inflator rates, covers, and steering wheel clock orientation. The response measurements on the dummy's arm are compared with relevant biomechanical data. The results indicate that certain air bag modules produced bending moment levels in the dummy's arm which would exceed the published skeletal fracture reference values, whereas other modules resulted in responses at or below those thresholds.
Abstract