Stability of Rotating Space Vehicles

The problem of stabilizing space vehicles is considered, and it is shown that at least for some important applications the intrinsic stabilization obtained by rotation of the entire vehicle is advantageous. Investigations which have been made of natural methods for damping nutational vibrations of such rotating vehicles are discussed in the following manner. A laboratory simulator is described which has been found very useful in testing the various devices suggested for nutation damping. A number of references to recent analytical studies of nutation dampers are given. One approach, a rigorous attack on a simplified arrangement, is described in some detail. Also, formulas based on an intuitive approach are derived for the design of both the pendulum and the mercury dampers. Finally, an interesting and, it is believed, entirely new basic design criterion for stable operation of coupled rotating bodies, such as a space vehicle with pendulum nutation dampers, is demonstrated.