Development and validation of a lateral MREs isolator Zhi-Wei Xing a , Miao Yu* a , Jie Fu a , Lu-Jie Zhao a a Key Laboratory for Optoelectronic Technology and Systems of Ministry of Education, College of Optoelectronic Engineering, Chongqing University, Chongqing, China 400044 ABSTRACT A novel lateral vibration isolator utilizing magnetorheological elastomers (MREs) with the field-dependent damping and stiffness was proposed in order to improve the adaptive performance. First, soft silicone rubber MREs with a highly adjustable shear storage modulus was fabricated. Then, the lateral MREs isolator was developed with a unique laminated structure of MRE layers and steel plates, which enables to withstand large vertical loads and adapts to the situation of large lateral displacement. Also, the electromagnetic analysis and design employed electromagnetic finite element method (FEM) to optimize magnetic circuit inside the proposed device. To evaluate the effectiveness of the lateral MREs isolator, a series of experimental tests were carried out under various applied magnetic fields. Experimental results show that the proposed MREs isolator can triumphantly change the lateral stiffness and equivalent damping up to 140% and 125%, respectively. This work demonstrates the performance of the designed lateral MREs isolator and its capacity in vibration mitigation for the complex situation. Keywords: Magnetorheological elastomers, finite element method, isolator, vibration mitigation 1. INTRODUCTION Lateral base isolators have been widely employed in the manufacture procedure of semiconductors and optical components to guarantee the quality of ultra-precision products for the high-tech equipment, due to the requirements of a restrictive environment with extremely limited vibration. The main objective of using the base isolator is to reduce the inertia force transmitted into the superstructures so as to avoid related damage phenomena 1 . However, due to the passive nature of existing lateral base isolators, once the base isolation system has been designed and installed, it cannot change the performance of structures against different types of vibrations. To overcome this challenge, it is extremely desired to develop a smart lateral base isolator which enables to withstand large vertical loads while possessing controllable lateral stiffness. In addition, variable damping and stiffness isolators are prepared to avoid resonant response during complex excitation motions by altering the properties of the structure. Magnetorheological elastomers (MREs) have the potential to be adopted as semi-active controllable elements in base isolation, because their damping and stiffness change when subjected to an external magnetic field. MREs are solid analogous to magnetorheological fluids (MRFs), with micron-sized magnetic ferromagnetic particles dispersed in a polymer matrix 2-4 . Due to the advantages of no-sedimentation of particles in certain matrix, fast response, and wide range of operation frequency, a great deal of efforts have been made by investigators and researchers in recent years to employing MREs to design smart adaptive absorbers or isolators, such as adaptive tuned vibration absorber 5 , real-time tunable stiffness and damping mount 6 , vehicle seat suspension isolator 7 , seismic base isolator 8,9 , variable stiffness and damping isolator (VSDI) 10 . All of the above MREs devices have achieved controllable performance under external applied electric current. In this paper, we explore the feasibility of a novel lateral MREs isolator incorporating MREs materials. The adjustable base isolator is then fabricated utilizing a traditional laminated bearing structure. Also, the electromagnetic analysis employed electromagnetic finite element method (FEM) to optimize magnetic circuit inside the proposed device. Comprehensive experimental testing was conducted to evaluate the performance of the proposed lateral MREs isolator. *yumiao@cqu.edu.cn; phone 86 23 65111016; fax 86 23 65111016 Ninth International Symposium on Precision Engineering Measurement and Instrumentation edited by Jiubin Tan, Xianfang Wen Proc. of SPIE Vol. 9446, 944645 · © 2015 SPIE CCC code: 0277-786X/15/$18 doi: 10.1117/12.2181830 Proc. of SPIE Vol. 9446 944645-1 Downloaded From: http://proceedings.spiedigitallibrary.org/ on 03/23/2015 Terms of Use: http://spiedl.org/terms