Host: The Japan Society of Mechanical Engineers
Name : Dynamics and Design Conference 2018
Date : August 28, 2018 - August 31, 2018
This paper describes natural frequency reduction of a seismic isolator table using the negative viscous damping and negative Coulomb friction. Noo et al. proposed the seismic isolator table using a DC motor and electrical circuit. The natural frequency and the damping ratio of the isolator can be tuned using the electrical circuit. In addition, the resonance is suppressed by the vibration absorber using an LRC circuit. The problem of the deflection and buckling of a spring was solved by this method; however, the natural frequency of the isolator could not be reduced sufficiently because a viscous damping and Coulomb friction were not negligible. Therefore, we proposed a new electrical circuit that cancels the viscous damping and Coulomb friction in this research. The effectiveness of the proposed method was verified through the simulations and experiments.
