An alternative interpretation of the Grioli gyroscope suspension points

Abstract: We present a detailed analysis of all possible regular precessions of a heavy asymmetric body with a fixed point not coinciding with the center of mass. The calculations are done in terms of the rotation matrix, by writing the Euler-Poisson equations with all involved vectors parameterized in the Laboratory frame. It is shown that a regular precession is possible if the suspension point is chosen on the straight lines (lying in the principal plane) which are frontiers of the regions where, as the distance from the center of mass increases, the permutation of intermediate and largest moments of inertia occurs. Like the spin of an electron in quantum mechanics, the frequency of regular precession in classical mechanics turns out to be rigidly fixed by two values, i.e., quantized.