Energy Harvesting Using MEMS Porous Functionally Graded Piezoelectric Cantilever Beam

This study deals with the analytical design of a vibrational energy harvester which is com-posed of functionally graded piezoelectric material. The effects of porosity existence on the responses of the FG piezoelectric MEMS bimorph cantilever beam is investigated with both axial and transverse deformations. Furthermore, Hamilton’s principle is utilized in order to obtain the governing equations of motion and also, they are solved by Galerkin method. Since the effect of elastic mode shapes related to lower frequencies are overcoming the high-er frequencies mode shapes, some of the first mode shapes are utilized for studying the trans-verse shape changing of Euler-Bernoulli beam. Moreover, the frequency response is carried out for the case of near resonance frequencies due to the effects of volume fraction index and porosity coefficient with different values. The output power of the energy harvester is pre-sented with respect to the output resistance in order to obtain the enhanced efficiency.

Keywords:

piezoelectric , functionally graded materials , porosity , bimorph cantilever beam.