Thoracic biofidelity assessment of the THOR mod kit ATD

Parent, Daniel P.<sup>1</sup>; Craig, Matthew<sup>1</sup>; Ridella, Stephen A.<sup>1</sup>; McFadden, Joseph D.<sup>1</sup>

During the upgrade of the 50th percentile male THOR anthropomorphic test device (ATD) from the Alpha level to the NT level, the low-speed Kroell hub impact corridor was selected as the design requirement for blunt thoracic impact response. Although this requirement was reiterated during the development of the THOR Mod Kit, it has been documented that the response of the thorax does not meet the design requirement. There were three objectives to this study: first, to quantify the thoracic biofidelity of frontal impact ATDs; second, to demonstrate that the Mod Kit design level of the THOR ATD meets the intended the low-speed blunt thoracic impact biomechanical response requirement; and third, to evaluate the influence of the SD-3 shoulder design on the performance of the THOR ATD in blunt thoracic impact. Data were collected from low-speed (4.3 meters per second) blunt thoracic impact tests of several variations of 50th percentile male ATDs: Hybrid III, THOR-NT, THOR Mod Kit, and THOR Metric. The latter two THOR variations were tested both with and without an updated shoulder (“SD- 3”) used in the European Union’s THORAX project demonstrator. The thoracic force-deflection responses were qualitatively compared to the existing low-speed thoracic impact response corridors: the Kroell corridor, based on internal deflection, and the Lebarbé corridor, based on external defelction. The THOR-NT and THOR Mod Kit responses showed force levels similar to the biomechanical response requirements, but deflections lower than desired. The repeatability array carried out on one THOR Mod Kit ATD showed no notable variations in force or deflection. Quantitative comparison of the ATD impact response to the biofidelity corridors was carried out using a biofidelity ranking system, which was used to demonstrate that the response of the THOR ATDs are not differentiable from the human subjects used to develop the corridors. The low-speed blunt thoracic impact response requirement for the THOR Mod Kit design level was met both qualitatively and quantitatively. The installation of the SD-3 shoulder influenced the resulting biofidelity ranking system results, but did not change the order of ranking of either the THOR Mod Kit or the THOR Metric ATDs. This study is limited by the volume, quality, and specificity of the PMHS data.

Year

Entry

2005

Shams T, Rangarajan N, McDonald J, Wang Y, Platten G, Spade C, Pope P, Haffner M. Development of THOR NT: enhancement of THOR Alpha-the NHTSA advanced frontal dummy. In: Proceedings of the 19th International Technical Conference on the Enhanced Safety of Vehicles (ESV). June 6-9, 2005; Washington, DC.

2004

Lessley D, Crandall J, Shaw G, Kent R, Funk J. A normalization technique for developing corridors from individual subject responses. In: Proceedings of the SAE World Congress & Exhibition. March 8-11, 2004; Detroit, MI. Warrendale, PA: Society of Automotive Engineers. SAE 2004-01-0288.

2007

Instrumentation for impact test, I: electronic instrumentation. Society for Automotive Engineers International; July 2007. SAE J211-1.

2012

Saunders J, Craig M, Parent D. Moving deformable barrier test procedure for evaluating small overlap/oblique crashes. SAE Int J Commer Veh. July 2012;5(1):172-195. SAE 2012-01-0577.

1974

Neathery RF. Analysis of chest impact response data and scaled performance recommendations. In: Proceedings of the 18th Stapp Car Crash Conference. December 4-5, 1974; Ann Arbor, MI. Warrendale, PA: Society of Automotive Engineers:459-493. SAE 741188.