Broadening the Frequency Bandwidth of a Tire-Embedded Piezoelectric-Based Energy Harvesting System Using Coupled Linear Resonating Structure

The efficiency of single-degree-of-freedom (SDOF) vibration-based energy harvesters significantly drops when the resonance frequency of the harvester is different from that of the ambient vibration. In this study, a novel piezoelectric-based energy harvesting mechanism is introduced for rotary motion applications, which can generate power over a broad range of angular velocities of the wheel. The proposed design, which comprises a coupled spring-mass system attached to a PZT beam, has the advantage that it can easily be tuned in an off-line position by simply changing the tip mass and/or spring stiffness. A theoretical and experimental study is undertaken to check the performance of the proposed design for the range of speeds typical of commercial tires. It is shown that by tuning the resonance frequency of the mass-spring system the design can significantly increase the frequency bandwidth of the energy harvester.