Exploring irregular vibrations and chaos by the wavelet method
Ülo Lepik · Proceedings of the Estonian Academy of Sciences Engineering · 2003
The paper cosiders possibilities of exploring nonlinear structural vibrations and detecting chaos by the wavelet method.The signal is decomposed into several lower resolution components.Some numerical quantities for characterizing the signal (wavelet energy distribution, Shannon and threshold entropy, similarity index, self-similarity) are introduced.Noisy systems are discussed.An example, in which the noise transfers chaotic motion to regular vibrations, is described.The wavelet packet method is applied; it is shown that such an approach allows to decrease the width of the frequency bands and gives the possibility to distinguish chaotic vibrations from random motion.