Design optimization of piezoelectric energy harvesting cantilever for medical devices

Abstract

Energy harvesting from the human body is considered as an effective solution for powering biomedical systems. More particularly, the piezoelectric energy recovery from the human body associated mechanical vibrations is discovered to represent a highly promising solution. Relevant research works as perceived, in the related literature, turns out to reveal showed that the harvested power depends on several intervening factors such as the geometry, size and materials used in the construction of the piezoelectric cantilever. In addition, the reduction and the change of the design of the piezoelectric system appear to constitute important factors in output power enhancing process. In this context, the present work is conceived to propose a novel design of the piezoelectric cantilever. Accordingly, a special study dealing with conventional rectangular shape of the piezoelectric energy harvester is conducted. Hence, the major contribution of this study consists in an attempts to provide a newly designed cantilever of a new shape in a bid to enhance the scavenged power for low frequencies. To this end, various structures are tested and compared through implementation of the finite element method (FEM). The proposed associated performance is analyzed in terms of such factors as the von Mises stress, displacement, voltage and output power. The ultimate simulation results prove to indicate that the proposed architectural design turns out to be able to generate an electric power of a range of 14.11 ìW at a resonant frequency of 8.5 Hz. It is also worth noting that the advanced novel shape is discovered to exhibit the most effective performance levels in respect of some other observed designs subject of investigation.