On exploiting the transition of nonlinear characteristics of a broadband piezoelectric energy harvester for tuning it to low and high-frequency applications

In this work, the applicability of nonlinear piezoelectric energy harvesters is demonstrated for high and low-frequency applications. An axially loaded piezoelectric patched beam model is derived considering in-plane stretching. The harvester setup is developed in the laboratory, and the energy-based numerical model is validated with experimental results. Optimum dimensions of the harvester are obtained. The broadband nature of the harvester is explored, considering nonlinear effects and axial loads on the harvester's performance. The applicability of the proposed harvester is demonstrated meaningfully by exploiting bifurcation between hardening and softening types of non-linearity by adjusting axial loads with the help of a simple tunable harvester setup.