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Optimal parameters estimation and vibration control of a viscoelastic adaptive sandwich beam incorporating an electrorheological fluid layer

The complex shear modulus of an electrorheological (ER) adaptive sandwich beam is optimally estimated to model the system for vibration control. In the composition of a three layered beam, the ER fluid layer is embedded between two constraining layers. Using finite element (FE) method, the governing equations of the composite viscoelastic beam are derived. The developed model is compared with the results found in the literature. In addition, for a fabricated ER sandwich beam, the ASTM E756 standard is employed to estimate the complex shear modulus of the viscoelastic layer in different electric fields. An optimization procedure is conducted based on particle swarm optimization (PSO). In this process, the rough estimation of complex shear modulus extracted by ASTM E756 is modified to correlate the results of the FE model and the experimental tests. The updated FE model is mapped into an appropriate form that can be used for control objectives. Finally, a semi-active sliding mode control is utilized to attenuate the vibration of the adaptive sandwich beam by tuning its electric field dependent characteristics.