Determination of Physical Data of the Head. I. Center of Gravity and Moments of Inertia of Human Heads

摘要

A study was conducted on fresh, unpreserved human heads of 19 male and 2 female cadavers to determine the three-dimensional location of the center of gravity and the moments of inertia about any axis related to an anatomically based coordinate system. For X-ray anthropometry radiographs were taken in three positions. In the sample the ages at death range from 19 to 64 years, the body lengths from 156 to 185 cm, and the body weights from 53 to 95 Kg. The weights of the dissected heads range from 3,656 to 5,257 Kg. The center of gravity is located almost exactly in the mid-sagittal plane (+ or - 0.3 cm), 2.2 to 4.3 cm above the Frankfort plane, and 0.2 to 1.3 cm in front of an axis connecting the external auditory meati. The inertial ellipsoid is degenerated to a rotational ellipsoid with the axis pointing to the forehead under an angle of 45 to 69 degree to the Frankfort plane. The principal moments about this axis range from 110 to 198 Kg. sq cm, the others from 136 to 274 and 167 to 298 resp.