Physical Reality in FE Head Models: Rotation and Strain

The object of this paper is to highlight the potential limitations of numerical procedures and the need to capture the relevant physics in the FEA models for head impact studies. This is accomplished through a discussion on stress update objectivity, which assumes particular importance because it affects the accuracy of stress and strain calculations when large displacements associated with rotations, as seen in head impacts, are involved. Inaccurate stress and strain results will also result due to material rotation if the objectivity is not maintained.