Vibration control of structures with self-sensing piezoelectric actuators incorporatingadaptive mechanisms

Abstract

In a piezo-based self-sensing actuation (SSA) configuration, the control signal is mixed withthe signal due to mechanical response. The success of SSA relies on the extraction ofthat mechanical response from the mixed signal. Owing to the relatively highamplitudes of those two signals and the ambience varying property of the equivalentcapacitance of the piezoelectric element, a fix designed bridge circuit in the SSAconfiguration would extract a corrupted mechanical response under the variation of thepiezoelectric capacitance. This would degrade the system performance or evendestabilize the closed loop system. In this paper, an adaptive compensation isproposed to combine with the SSA technique to develop a vibration controller thatis capable of extracting the true sensing signal due to structural deformation.The results of this study illustrate that the combined design can simultaneouslysuppress the structural vibration during the piezoelectric capacitance variation.