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Two Highway Safety Research Institute (HSRI) dummies were tested and evaluated. Based on the analysis given, the HSI dummy should not be used for vehicle qualification testing. However, many of its components offer viable alternatives for future dummy development. The dummy was found to have inadequate biomechanical fidelity in the head, neck, and chest, although its characteristics were very promising and, as a whole, biomechanically superior to the Hybrid II. Its repeatability and reproducibility in dynamic component tests were better than the Hybrid II dummy. In particular, the HSRI friction joints were outstanding in repeatability and had a significant advantage in usability in that they do not require resetting between tests. In three-point harness and ACRS systems tests, the values of injury criteria produced by the HSRI dummy were generally lower than those obtained with the Hybrid II, especially the femur loads in the ACRS tests.

A viscoelastic neck structure that responds to impact environments in a manner similar to the human neck is described. The neck structure consists of four ball-jointed segments and one pin-connected “nodding” segment with viscoelastic resistive elements inserted between segments that provide bending resistance as well as the required energy dissipation. Primary emphasis was placed on developing appropriate flexion and extension responses with secondary emphasis placed on axial, lateral, and rotational characteristics. The methods used to design the resistance elements for the neck structure are discussed. Three variations of the resistive elements have been developed that meet the response characteristics based on the data of Mertz and Patrick. However, no single resistive element has satisfied the flexion and extension characteristics simultaneously, but such an element appears to be feasible.

The principal objectives of this study were first to obtain experimental curves of angulation versus moment of resistance of the human neck in hyperextension and lateral flexion, and second to determine angular limits short of significant injury observable in the unembalmed subjects employed in the study. The first of the tests were of the “static” type with load applied over a period of approximately 1s. To determine the applicability of the data to dynamic conditions, tests were also made of the dissected neck at angulation velocities comparable with those of typical accidental injury. Overall resisting moment and injury threshold were similar under the dynamic loading, but somewhat greater moment of resistance was noted during the (earlier) portion of the loading cycle when angular velocity was greatest.