Bifurcation phenomena of a forced self-oscillatory system with hard characteristics.

There are many reports on the bifurcation phenomena of a forced self-oscillatory system and a hard oscillator. One of them suggested the formation of a forced self-oscillatory system by the Duffing–van der Pol equation with linear restoring term. When the restoring force has a suitable negative linear term, the system has hard characteristics as well as soft oscillation. This paper deals with the bifurcation phenomena of subharmonic and higher-harmonic oscillations corresponding to the hard characteristics in the system. It is found that the frequencies at the unstable periodic points synchronize with the external force. © 1999 Scripta Technica, Electron Comm Jpn Pt 3, 82(9): 1–9, 1999 [ABSTRACT FROM AUTHOR]