Summary

Proceedings of the 2013 International Symposium on Nonlinear Theory and its Applications

2013

Session Number:B3L-D

Session:

Number:338

Intrinsic Localized Oscillations and Their Interactions in an Articulated Structure with Softening Elastic Couplers

Yosuke Watanabe,  Fuminori Hata,  Nobumasa Sugimoto,  

pp.338-340

Publication Date:

Online ISSN:2188-5079

DOI:10.15248/proc.2.338

PDF download (578KB)

This paper demonstrates numerically excitation of intrinsic localized modes (ILMs) and their interactions in transverse oscillations of an articulated structure with free ends. The structure consists of many, identical rigid members, which are connected to adjoining ones by elastic couplers yielding nonlinear restoring moments in angular displacements, and are supported by linear springs at center of mass of each member. The structure extends straight in equilibrium and the displacements are restricted in a plane. Eigen-frequencies of the linearized system are confined in a band with a lower limit determined by the elastic supports. Here concerned is a case that the coupler is of soft-spring type in angular displacements between adjacent members, where the restoring moment has the maximum or minimum. For a certain range of parameters involved in the system and initial conditions, a movable ILM can be excited at a frequency lower than the smallest eigenfrequency. If two ILMs of equal amplitude are excited simultaneously, it is revealed that (1) they are coalesced into a single ILM, (2) they are collapsed into ripples or (3) they are separated to be trapped at both ends.

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