Vibration analysis of a cantilever beam with viscoelastic neutralizers using fiber Bragg gratings

Abstract

In this paper the vibration analysis of a cantilever beam with viscoelastic neutralizer using fiber Bragg gratings (FBG) is presented. The optimal design, of the neutralizer, is achieved through a robust methodology developed by the Research Group on Vibrations and Sound in Mechanical Systems (GVIBS) at Federal University of Paraná (UFPR). Such methodology uses the Finite Element Method (FEM) to obtain the modal analysis of the system that will be controlled. The Generalized Equivalent Parameters (GEP) and Nonlinear Optimization Techniques (NLOT) are applied. The viscoelastic neutralizer was projected to control the range of frequency 250 Hz to 470 Hz. To verify the efficiency of the neutralizer the response of the FBG was compared with the response of the piezoelectric accelerometer. Both systems were positioned close to the clamped part of the beam. The analysis presents the efficiency of the viscoelastic neutralizer, proven by decrease of amplitude for the analyzed range when using the optical technique (25 dB) and traditional sensor (32 dB). This study allows validating the effectiveness of the vibration measurements of the FBG to the viscoelastic neutralizers projects.