The objectives of this study are: (1) to evaluate the External Peripheral Instrument for Deformation Measurement (EPIDM), and to arrive at a methodology to be used in impact experiments; and (2) to conduct sled tests on an unembalmed human cadaver and a 50th percentile Hybrid III manikin to determine the thoracic deformation contours and, using these contours, to evaluate injury criteria such as normalized chest compression and viscous response. The EPIDM methodology used was based on three steps: (i) prior to any testing, zero all gauges on a flat surface; (ii) instrument the surrogate last before conducting the sled experiment; and (iii) after the test, repeat the calibration procedure to ensure a proper working of all the gauges. A three-point belt restrained human cadaver and a Hybrid III manikin surrogate underwent sled tests at 48 kph velocities. These tests indicated that the EPIDM device can follow the dynamic thoracic deformations at impact. The deformation contours also permitted the computation of the following variables: (a) normalized compression histories; (b) chest compressive velocities; and (c) the viscous response (product of the normalized compression and the compressive velocity) characteristics. The studies suggest the potential of the EPIDM to derive injury criteria in an attempt to assess the crashworhtiness of vehicular structures.
Abstract