EVALUATION OF THE ROBUSTNESS PERFORMANCE OF A FUZZY LOGIC CONTROLLER FOR ACTIVE VIBRATION CONTROL OF A PIEZO-BEAM VIA TIP MASS LOCATION VARIATION


Tezin Türü: Yüksek Lisans

Tezin Yürütüldüğü Kurum: Orta Doğu Teknik Üniversitesi, Fen Bilimleri Enstitüsü, Türkiye

Tezin Onay Tarihi: 2019

Tezin Dili: İngilizce

Öğrenci: ERDEM RAHMİ ŞENÖZ

Danışman: Melin Şahin

Özet:

This thesis presents a study in which a robust Fuzzy Logic Controller (FLC) is designed to suppress both free and the first resonance of a piezo-beam even if the position of the tip mass located on the beam varies. The cantilever aluminum piezo-beam involves the piezoelectric patches bonded on the surfaces to be used as a sensor and actuator for the vibration control and the displaceable tip mass attached to the free end of the piezo-beam and used to change the system parameters for checking the robustness of the designed controller. At first, the experimental setup for actively controlled piezo-beam is introduced and the system identification of the piezo-beam for all positions of the tip mass is performed. The frequency response functions are then investigated via the System Identification Toolbox in Matlab in order to be used in the simulation studies. Then, a FLC is designed via Fuzzy Logic Toolbox in Matlab. The performance of the FLC is the evaluated through various simulation and experimental studies such as free vibration suppression, forced vibration suppression at the first resonance frequency and the forced vibration suppression within the frequency span covering the first resonance of the piezo-beam. Moreover, the performance in the robustness of the FLC is investigated by changing the position of the tip mass. This thesis shows that the first resonance of the piezo-beam is suppressed by the designed FLC developed for a certain position of the tip mass even if the dynamics of the piezo-beam is changed due to change in the position of the tip mass by providing a certain degree of robustness.