Abstract
This paper presents an experiment on chaotic oscillation of a thin annular plate. The plate is clamped at internal boundary and is free along outer circumference. When the plate is subjected to periodic excitation, a large-amplitude response is generated by resonance. The time response is measured by a laser displacement sensor and is examined by the Poincare maps and the Lyapunov Exponent. Predominant response is confirmed to be chaos due to internal resonance. Furthermore, the time response of the plate is measured at four points simultaneously and principal components were obtained by the Karhunen-Loeve transformation. It is found that vibration mode of one nodal diameter and mode without node contribute to the chaotic oscillation. Principal component analysis for the short time period of the chaotic response shows that nodal lines in the first mode of vibration irregularly propagates to the circumferential direction, which suggests the existence of the traveling waves in the chaotic response of the annular plate.
