Effect of nonlinearity on the dynamics of spinning spacecraft appendages with an offset

The paper considers dynamics of appendages connected to a spinning spacecraft with an offset from the spacecraft centre of mass. It is observed that; even if the so-called "premature linearization" is avoided and geometric nonlinearity as well as nonlinear terms in rotational rates are taken into account, neglecting second order terms in elastic displacements may still give incorrect information about the stability of the system. If the second and higher order terms involving the small elastic deformations are neglected, the system is stable for negative offset, but unstable for positive offset, However, if these higher order terms are retained, the system is stable for both types of offset. The cause of this anomaly is explained in the paper.