Phase-Plane Analyses of Parametrically and Self Excited Mechanical Systems

In order to investigate the behaviors of parametrically and self-excited mechanical systems, graphically analytic methods in the phase plane are proposed. Unstable phenomena like parametric and self-excited vibrations happen to appear in rotating machinery with a crack, a rub, the looseness and so on. Such unfavorable vibrations should be detected and predicted as early as possible. In this paper, their characteristics are investigated and a fundamental view for describing and analyzing nonlinear models is presented