Fifth International Congress on Sound and Vibration December 15-18, 1997 Adelaide, South Australia Active Control of Nonlinear Vibration in a Flexible Cantilever Beam

The aim of this paper is firstly to address the consequences of the nonlinear interactions between higher order modes and the first order mode of a flexible cantilever beam. The tested cantilever beam exhibited numerous nonlinear phenomena that are commonly observed in many flexible structures. The experimental results have shown that active control of the nonlinear vibration in a flexible structure is effective. Secondly, the paper describes how the nonlinear vibration in the cantilever beam was cancelled using a digital feedback controller implemented in a dSpace TM Digital Signal Processing board. It has been demonstrated experimentally that the on-line feedback controller was capable of canceling the low frequency vibration generated in the flexible cantilever beam due to nonlinear interaction between the modes of the beam. This control scheme has considerable potential for canceling of nonlinear vibration in large structures such as aircraft, ships, etc. in order to reduce stress and fatigue of these structures.