Optimal Locations of Piezoelectric Patch on Wideband Random Point-Driven Beam for Energy Harvesting

Abstract

Inspired by the phenomenon of localized response intensification in wideband random vibration, a novel procedure is proposed to determine the optimal locations of piezoelectric patch attaching on wideband random point-driven beam for vibration energy harvesting application. The optimization objective is to maximize the mean output voltage, and the optimal locations lie on the vicinities of the excited point and its symmetric point. The optimal locations keep invariable regardless of typical symmetric boundary conditions (such as the clamped, simply supported, free, and torsional spring supports), the lower and upper cutoff frequencies of the band-limited white noise, and the external damping provided that the excited point is not too close to boundaries and the bandwidth of excitation covers enough modes of primary structure. The robustness of optimal locations is illustrated from an electromechanical coupling model and is qualitatively verified through experimental testing on a random-excited aluminum beam with piezoelectric patches attached on its surface.