C. Gregory Shaw

Comparative evaluation of the THOR advanced frontal crash test dummy

Abstract Ten 48 km/h frontal sled tests were conducted to evaluate the biofidelity of the THOR dummy. Three replicate tests were conducted with THOR, three with a 50 th percentile male Hybrid III dummy, and four with post-mortem human surrogates (PMHS). The tests, conducted in a buck representing a mid-size US sedan, included a force-limited three-point belt system with buckle-side pretensioner and a driver side airbag. Following the tests, select parameters were used to compare THORs responses with those of the Hybrid III dummy and the PMHS. The tesults were mass scaled in order to account for size differences between the subjects. Based on cadaveric response corridors, the sled test results provided evidence that THOR is more biofidelic than the Hybrid III dummy. THOR lap belt loads, head acceleration, and movement of the anterior chest wall were more similar to those of the PMHS than were those of the Hybrid III. However, THOR recorded less head forward movement and pelvic acceleration than did the PMHS.

Kinematics of the unrestrained vehicle occupants in side-impact crashes.

A test series involving direct right-side impact of a moving wall on unsupported, unrestrained cadavers with no arms was undertaken to better understand human kinematics and injury mechanisms during side impact at realistic speeds. The tests conducted provided a unique opportunity for a detailed analysis of the kinematics resulting from side impact. Specifically, this study evaluated the 3-dimensional (3D) kinematics of 3 unrestrained male cadavers subjected to lateral impact by a multi-element load wall carried by a pneumatically propelled rail-mounted sled reproducing a conceptual side crash impact. Three translations and 3 rotations characterize the movement of a solid body in the space, the 6 degrees of freedom (6DoF) kinematics of 15 bone segments were obtained from the 3D marker motions and computed tomography (CT)-defined relationships between the maker array mounts and the bones. The moving wall initially made contact with the lateral aspect of the pelvis, which initiated lateral motion of the spinal segments beginning with the pelvis and moving sequentially up through the lumbar spine to the thorax. Analyzing the 6DoF motions kinematics of the ribs and sternum followed right shoulder contact with the wall. Overall thoracic motion was assessed by combining the thoracic bone segments as a single rigid body. The kinematic data presented in this research provides quantified subject responses and boundary condition interactions that are currently unavailable for lateral impact.

External biofidelity in lateral impact measurement of global and local forces

A study was conducted to develop high-resolution external biofidelity data for the response of post-mortem human surrogates (PMHS) in side-impact loading. This study implemented stationary PMHS (N = 3) impacted by a wall moving at a constant velocity. The wall was subdivided into 15 impact plates, each instrumented to record the normal and shear forces as well as reaction moments about the shear axes. A method to determine the time-history of the centre of pressure (COP) of each load plate was developed and validated in both quasi-static and dynamic loading conditions. A validation test demonstrated that the COP can be predicted to within 1 cm for loads generally achieved by the shoulder and pelvis. The repeatability of COP was very good for the pelvis, where maximum variation was 1.44 cm, but higher for the thorax (3.4 cm) and shoulder (4.1 cm). Patterns of COP motion on the pelvis plate were consistent for all subjects.