Vibration Analysis of a Cantilever Composite Beam by Equivalent MassSpring-Damper Systems

Composite materials are widely used in industrial structures such as manipulators because they are lightweight and durable. In this work, the vibration analysis of a cantilever composite beam with [0/90] lay-up was studied. An end point mass was added to the structure. An initial displacement was applied to the end point and the free vibration was analyzed experimentally first. Exponential decay was found. Natural frequencies were determined by taking the Fast Fourier Transform of the vibration signal. The system was analyzed in ANSYS and simulation results were obtained. The damping coefficient was determined by trial using the experimental exponential decay. An equivalent massspring-damper model (MSD) was established using static deflection, natural frequency and exponential decay obtained experimentally or by simulation. MSD-analytical results were obtained by the Laplace transform method. The experimental, simulation, and analytical results were compared for different end point initial displacement values. It was observed that the results are in good agreement.