This research work aims to investigate the presence of four nonlinear characteristics (i.e., hysteresis, saturation, creep, and uncertainty vibration) when a piezoelectric patch material acts as an actuator and sensor for the active vibration suppression of a cantilever beam. The parameters such as different operating frequencies and voltages are taken into account for the piezoelectric patch material characterization and the vibration before and after activation of a proportional–derivative–integral controller in an active vibration suppression system are measured. The effect of different proportional–derivative–integral controller tuning methods, frequency independent, and frequency dependency excitations are the three main contributions to evaluate the performance of active vibration suppression system. From the results, the piezoelectric actuator posed all the four nonlinearity effects while only three are observed in the sensor characteristics, and these effects increased significantly with the increase of operating frequencies and voltages. For the frequency-independent excitation of the active vibration suppression system, the vibration attenuation of the beam shows an improvement from low to higher excitation frequency, except at 500 Hz because of the saturation effect. In terms of controller performances, the proportional gain step-up method shows the best performance by scoring 3/5 of highest vibration attenuation percentages compared with manual and Ziegler–Nichols methods. For the frequency-dependent excitation, the effective frequency range for the active vibration suppression system is determined between 75 and 245 Hz with the highest vibration attenuation of 79.60% occurred at the second natural frequency of the beam.
Active Vibration Suppression in a Flexible Cantilever Beam Using Fuzzy Logic Controllers.(Dept.E)
