Abstract
In the authors' previous report, a self-sensing actuator with laminated piezoelectric films was proposed, and the validty of the proposed method was shown by performing their vibration control experiment of a beam and a rectangular plate. However, the slight difference between circuit components such as piezoelectric capacitance and their variation with time and temparature made the closed-loop system unstable. Therefore, variable resistors needed to be fine-tuned manually so as to keep the bridge circuit balanced. However, this adjustment work was cumbersome and complicated in that it was needed to be done by trial and error. In this study, a distributed smart damper using four laminated piezoelectric films is developed by using an analog multiplier and a digital signal processor in order to provide the bridge circuit with self-tuning function. In the experiment, this smart damper is applied to a cantiliver beam. After operating the self-tuning function according to the least-mean-square algorithm, free vibration control of the first mode of a cantilever beam is performed with a convergent parameter. It is verified that enough control effect is actually obtained and this control effect is almost equal to the effect obtained in cases where the bridge circuit is tuned manualy.
