IDENTIFICATION OF COUPLED NON-LINEAR MODES FROM FREE VIBRATION USING TIME-FREQUENCY REPRESENTATIONS
✍ Scribed by S. BELLIZZI; P. GUILLEMAIN; R. KRONLAND-MARTINET
- Publisher
- Elsevier Science
- Year
- 2001
- Tongue
- English
- Weight
- 489 KB
- Volume
- 243
- Category
- Article
- ISSN
- 0022-460X
No coin nor oath required. For personal study only.
✦ Synopsis
A new method based on time}frequency representations is presented for identifying the non-linear modal parameters of a multi-degree-of-freedom non-linear lightly damped mechanical system. The coupled non-linear modes are "rst introduced. It is shown that, by using the coupled non-linear modes, the free response can be expressed as a linear combination of frequency and amplitude modulated components. This suggests the use of time}frequency methods to characterize these modulation laws and then identify the coupled non-linear modes. These modulation laws are extracted by using an extended de"nition of the so-called &&ridges'' of the continuous Gabor transform, which enables a more accurate estimation. An identi"cation procedure of the coupled non-linear modes is proposed and the validity of the whole process is con"rmed by performing computer simulations of di!erent types of non-linear elastic dynamic systems.