## 摘要

An experiment with a test rig consisting of a symmetric rotor suspended by a spring device and excited by a series of nonlinear electromagnetic forces has been performed by Chang and Tung [Sound & Vib. 214 (1998) 853], to investigate the effects of an electromagnet processing highly nonlinear characteristics on general mechanical systems. A nonlinear mathematical model has been obtained by applying a modified conventional identification technique based on the principle of harmonic balance. In this study, analytical work is carried out on this identified nonlinear model by applying the first-harmonic approximation solution and the Floquet theory. The resulting criteria for bifurcations can be used to evaluate the operational range of a system employing such a nonlinear actuator. We also employ the method of Lyapunov exponents to show the occurrence of chaotic motion and to verify the above analyses. A comparison of the analytical results with those of the cxperimemt shows that the identified nonlinear model obtained from the experiment can predict and characterize the dynamics of a real electromagnetic system.

原文 | ???core.languages.en_GB??? |
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頁（從 - 到） | 2173-2174 |

頁數 | 2 |

期刊 | Japanese Journal of Applied Physics, Part 2: Letters |

卷 | 38 |

發行號 | 4 A |

出版狀態 | 已出版 - 1999 |