Vibration Control Of Flexible Beams On Electroheological Elastomers

Electrorheological fluids is a class of special material which could act prominently as actuators whose rheological properties can be readily controlled using an external electric field. These sandwich structures filled with Electrorheological fluids have adaptive control capabilities of varying the damping and stiffness of the beam by changing the intensity of applied electric field. They have been widely applied in vibration control of flexible structures. However, the electrorheological fluids, a suspension material is consisting of base and dispersed particles and many materials with high ER activity in use, the poor sedimentation and poor stability of most particles limit the potential applications to industry.ER elastomers is a new generation of ER materials. They are mixed with polarized particle and elastomers and solidified in electric field. The particles are polarized and form chain or fibrous structures in the two poles because of the electrorheological effect and they continue to gather bunches and columnar. ER elastomers is superior to ER fluids in sedimentation, coagulation, and stability of the particles. Furthermore, ER elastomers is more flexible, light, and easily prepared, all desirable properties in their applications. ER elastomers will have more potential application than ER fluids in engineering filed.The research is supported by the National Natural Science Fundation of China (No. 10802029). A general dynamics model is developed for a sandwich beam filled with ER elastomers undergoing large overall flexible beams. In electric field or no electric field are the ER elastomers consisted of silicone rubber, starch and silicon oil in fixed proportion and their mechanical properties were measured. They are prepared for the three-layer sandwich beams filled with the ER elastomers. In order to evaluate the vibration control effect of flexible beams with an ER elastomers material layer, the comparison and experimental tests are made to investigate the dynamic characteristics and vibration control of ER elastomers sandwich beam subjected to different electric field and extinction frequency, and experimental study on the feasibility and validity of the vibration control in the flexible beams filled with ER elastomers. By describing the ER elastomers as the viscoelastic materials with controllable complex shear modulus, a dynamic model of a sandwich beam filled with ER elastomers is developed by Hamilton principles and sandwich beam theories. By stetting up the theoretical model, the dynamics of the different electric field and geometric Dimension is simulated and analyzed and the relation between the natural frequency and loss factors and different electric field is explored. It is found that the model loss factors of the sandwich beam will increase as the applied electric fields and thickness of the ER elastomers layer increase; the natural frequencies will increase with an increase in the applied electric fields and decrease with the thickness of ER elastomers layer. The results indicate that the ER elastomers materials layer has a significant effect on the vibration suppression of the flexible beams when subjected to an electric field.