Non-planar, non-linear oscillations of a beam II. Free motions

Steady and unsteady free motions of compact beams with fixed ends are examined. It is found that in certain situations planar motions are unstable to out-of-plane perturbations and whirling motions occur. In resonant cases these whirling motions are of the beating type, whereas in non-resonant situations they have a steady-state behaviour.