论文部分内容阅读
Nonlinear vibrations of a flexible square cross-section cantilever subjected to harmonic excitation has been experimentally investigated in this paper. The first six orders linear natural frequencies obtained mathematically have been compared with those of observation，by which phenomena of frequency division and doubling are found. Frequency response curve has been drawn based on the observed points. Nonlinear character of sensitivity toward initial values has been studied and regareded to cause the curve. In the zones of resonance，two modes of modal combination have been found. The waveforms and amplitude spectrum are introduced to show that this simple sysetm can exhibit complicate nonlinear dynamic characteristics including periodic doubling bifurcations and chaotic motions under certain conditions.