Feedback Control of Piezoelectric Actuator Elastic Properties in a Vibration Isolation System

The design of a vibration isolation system utilizing a method to control the effective elastic stiffness of piezoelectric materials has been realized. The vibration isolation system consists of a piezoelectric actuator and an active analog circuit with an operational amplifier. The problem of a low stability of this system is analyzed and the method for the automatic stabilization and adjustment of the analog circuit by an additional feedback control is introduced. The impact of the proposed method on the transmissibility of vibrations through the vibration isolation system is experimentally verified on a preliminary device. It is shown that using the proposed method, it is possible to decrease the transmissibility of vibrations by an additional 20 dB compared to the transmissibility values achieved by a manual adjustment of the analog circuitry.