HORK Enterprises
3221 Quick Road
Holly, MI 48442, USA
 +1 (248) 328-0231
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Crash Dummy Models

Involvement with developing numerical models for Crash Test Dummies (formally known as Anthropomorphic Test Devices, or ATD's) started in 1991, when Henk was leading a database development program jointly sponsored by the TNO Crash-Safety Research Center and the Organization of German vehicle manufacturers F.A.T.

During this 18 month program, dummy databases were created for the DoT Side Impact Dummy and the 5th and 95th percentile Hybrid III dummies. Traveling between The Netherlands, Germany, and the United States an extensive program of analysis and validation testing was conducted. These tests included detailed geometrical and inertial measurements, as well as determination of deformation characteristics of vital joints and dummy segments. These measurements were conducted partly by the TNO Crash laboratory and by the CALSPAN Corporation working under contract to the US Government at Wright Patterson AFB., in Dayton, Ohio. Involvement with the dummy databases continued through regular updates and improvements, made possible by new features of the MADYMO program.
This culminated at the end of 1994 in a combined Multi-Body/Finite Element model of the DoT Side Impact Dummy, using the original MADYMO database and a database made available by the US National Highway Traffic Safety Administration (NHTSA). Finite Element descriptions allow for more accurate modeling of highly deformable structures, such as the rib cage of this dummy. They do, however, put a greater demand on compute resources, which in 1994 was still a concern for dummy models. The MADYMO Finite Element capabilities were being expanded though, following the successful implementation of finite element code for airbag analysis in prior years.

Dummy database development was picked-up again as part of the smart restraint system development at Breed Technologies, Inc. Using the existing dummy databases and the human geometry database program, GEBOD (developed by CALSPN at the Wright Patterson AFB), new dummy models for numerical analysis were developed, through scaling techniques based on the research of Bert Mertz, et. al. (SAE 890756).

The full set of adult simulation models consisted of a small female, an average female, an average male, a heavy male, and a tall male. Scaled models help in accident reconstruction research, when the crash victim can not be classified as either a "Small Adult Female", an "Average Adult Male", or a "Large Male".

With the ever increasing power of computers, the use of Finite Element techniques to describe the dummies, was becoming less of an issue. Finite element techniques discretize the surface in many small facets, which can give a more accurate desciption of the shape of the dummy than the geometric shapes, traditionally used by multi-body programs. This plays an important role in the areas of the head, neck, shoulders, and chest. As pointed out earlier, the Finite Element Method also allows for a better description of highly deformable parts such as the rib cage and the neck.

Based on a mesh released by the National Crash Analysis Center at George Washington University, Henk developed a series of dummy models. First for MSC.Dytran, which didn't have any dummy models at that time. This first model was extensively used for evaluation of ocupant interaction with a deploying airbag, for which MSC.Dytran provided the necessary computational fluid dynamics. Then the dummy models were also coded for Pam-Safe and LS-Dyna as there was a distinct advantage in using the same dummy models for all different solvers. The Dytran dummy models were released into the public domain through MSC.Software.

Now a full set of robust dummy models, used in the "Advanced Airbag Rule" testing is available, comprising the 3-year old and 6-year old child dummies, 5th percentile adult female and, 50th percentile adult male dummies. In addition our set of crash dummy models also comprises the 18-month old child and the 95th percentile adult male dummy, used in other performance testing. Of course, these models too, all are scalable. They are deployed in our occupant crash safety analysis facility at VirtualCrash.com