Nonlinear spacecraft dynamics with a flexible appendage damping and moving internal submasses

We study the attitude dynamics of a single-body spacecraft that is perturbed by the motion of small oscillating submasses a small flexible appendage constrained to undergo only torsional vibration and a rotor immersed in a viscous fluid. We are interested in the chaotic dynamics that can occur for certain sets of the physical parameter values of the spacecraft when energy dissipation acts to drive the body from minor to major axis spin. Energy dissipation which is present in all spacecraft systems and is the mechanism that drives the minor to major axis transition is implemented via the rotor. We not only obtain an analytical test for chaos in terms of satellite parameters using Melnikov's method but we also use extensive numerical simulation to check the range of validity of the Melnikov result.