Investigation of Various Cantilever Configurations for Piezoelectric Energy Harvesting Under Rotational Motion

The article investigates various cantilever configurations for energy harvesting from rotational motion. A piezoelectric cantilever beam is mounted radially on a rotating body with different configurations. A harvester of type A (type B) refers to an outward (inward) configuration of beam with the direction of the transverse vibration perpendicular to the rotational axis. On the other hand, a rotary harvester of the type C is an outward beam with the transverse vibration in parallel to the rotational axis. A unified approach based on the Hamiltonian principle is employed and the methodology for deriving the formulations is based on the distributed parameter method. The result shows that both the type A and type C enjoy the feature of passive self-tuning of resonance. But the type C exhibits better ability in tuning than the type A. In addition, the type B shows significant harvested power at the cost of loss of tuning ability.