title: Segmentation of a Vibro-Shock Cantilever-Type Piezoelectric Energy Harvester Operating in Higher Transverse Vibration Modes.
abstract: The piezoelectric transduction mechanism is a common vibration-to-electric energy harvesting approach. Piezoelectric energy harvesters are typically mounted on a vibrating host structure, whereby alternating voltage output is generated by a dynamic strain field. A design target in this case is to match the natural frequency of the harvester to the ambient excitation frequency for the device to operate in resonance mode, thus significantly increasing vibration amplitudes and, as a result, energy output. Other fundamental vibration modes have strain nodes, where the dynamic strain field changes sign in the direction of the cantilever length. The paper reports on a dimensionless numerical transient analysis of a cantilever of a constant cross-section and an optimally-shaped cantilever with the objective to accurately predict the position of a strain node. Total effective strain produced by both cantilevers segmented at the strain node is calculated via transient analysis and compared to the strain output produced by the cantilevers segmented at strain nodes obtained from modal analysis, demonstrating a 7% increase in energy output. Theoretical results were experimentally verified by using open-circuit voltage values measured for the cantilevers segmented at optimal and suboptimal segmentation lines.
authors.affiliation: Faculty of Mechanical Engineering and Design, Kaunas University of Technology, Studentu 56, Kaunas LT-51368, Lithuania. darius.zizys@ktu.edu.
authors.forename: Darius
authors.initials: D
authors.lastname: Zizys
authors.affiliation: Faculty of Mechanical Engineering and Design, Kaunas University of Technology, Studentu 56, Kaunas LT-51368, Lithuania. rimvydas.gaidys@ktu.lt.
authors.forename: Rimvydas
authors.initials: R
authors.lastname: Gaidys
authors.affiliation: Institute of Mechatronics, Kaunas University of Technology, Studentu 56-123, Kaunas LT-51368, Lithuania. rolanas.dauksevicius@ktu.lt.
authors.forename: Rolanas
authors.initials: R
authors.lastname: Dauksevicius
authors.affiliation: Institute of Mechatronics, Kaunas University of Technology, Studentu 56-123, Kaunas LT-51368, Lithuania. vytautas.ostasevicius@ktu.lt.
authors.forename: Vytautas
authors.initials: V
authors.lastname: Ostasevicius
authors.affiliation: Faculty of Informatics, Kaunas University of Technology, Studentu 50, Kaunas LT-51368, Lithuania. vytautas.daniulaitis@ktu.lt.
authors.forename: Vytautas
authors.initials: V
authors.lastname: Daniulaitis
keywords: numerical modelling; optimal segmentation; piezoelectric; resonant frequency; strain node; vibration energy harvesting