Controller design for piezo devices

A smart material is known to be able to generate large force in broad bandwidth in a compact size. In this paper, first, we tried modeling of the dynamics of the smart material. ARX model was used to model the dynamics of the smart material. We applied rectangular waves to the smart material and measured its responses with a strain gauge and a signal processing circuit. A 3^rd order model was obtained applying identification algorithm to the input/output data. Secondly, we designed a PID controller based on the obtained model to improve the characteristics of the smart material. Finally, we tested a performance of PID controller.