Design and Experiment of Inerter-Rubber Vibration Isolator Based on Parallel Inerter-Spring-Damper System

Since an inerter has been widely used in the field of vibration isolation, the combination of the inerter and the rubber part inevitably becomes a trend. In this work, a parallel inerter-spring-damper system (II-ISD) was introduced and analyzed for its performance on vibration isolation. Then, the optimal inertance-mass ratio and the frequency ratio at the minimum transmissibility were obtained. Based on the II-ISD system, an integrated vibration isolator was designed where the rubber part paralleled to the inerter, which was named as the inerter-rubber vibration isolator (IR). Then, its mechanical properties were simulated, and the mathematical model was established by considering the vibration isolation performance and the service life. Afterward, it was optimized by a programmed multi-objective genetic algorithm, and the optimal design parameters of IR were got finally. The experimental prototype of IR was processed, and its performance experiment was performed on the Mechanical Testing System (MTS) test bed. Experimental results show that the theoretical model of IR based on the II-ISD system is accurate; the resonant peak of IR is clearly lower than that of the rubber vibration isolator; the natural frequency decreases obviously. This work provides a design method for the serial product development, which has a practical engineering significance. With the development of machinery industry, vibrations (especially low frequency vibration) have become a big challenge for engineers (Xia et al. 2016a, 2016b; Sun et al. 2017). Scholars used various methods to weaken vibrations, such as the research of dynamic vibration absorber (Deng et al. 2006; Acar & Yilmaz 2012; Shen et al. 2016c, 2017) and rubber vibration isolator (Huang et al. 2014; Wang et al. 2014; Jin et al. 2015; Kim et al. 2015). In some special machinery areas, such as shipbuilding, wind power, and marine industry, the rubber vibration isolator has been commonly used and studied for years. However, a fatal shortcoming limits its development; that is, its vibration isolation performance at low frequencies is poor (Wen 2015). Therefore, the topic of solving this problem has been put on the agenda.