This paper describes new mathematical formulations, in the MADYMO-format, of the neck and the upper and lower torso elements of the Hybrid-III dummy. The modifications are assumed to improve the mathematical predictions of experimental results.

Like the dummy neck the suggested mathematical neck has five pivots, whose elastic properties have been established through measurements on the mechanical neck. The energy-dissipating properties have been tuned to obtain a response in agreement with the calibration requirements on the mechanical neck.

In addition to the improved correspondence with mechanical tests, the more detailed neck representation is assumed to improve the understanding of the neck response to various impacts. Furthermore, it has the potential to increase the biofidelity of the Hybrid-III dummy, at least indirectly, since it can link between results obtained from mechanical tests and results from simulations with the present, two-pivot neck, which has previously been shown to have a higher degree of biofidelity in comparison with the mechanical neck.

The upper torso has been made flexible by means of two connected elements, and the relevant properties of this system have been tuned to meet the calibration requirements on the mechanical chest.

For the lower torso, finally, a contact contour that well resembles the corresponding contour of the mechanical dummy has been designed. Since the lower torso is heavy as well as exposed to very high forces during a crash, a correct contact contour in this area is considered to be essential for obtaining a proper response from the mathematical model.