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Title: Frequency tunable electromagnetic vibration energy harvester using piecewise linear nonlinearity

Vibration energy harvesting is increasingly being seen as a viable energy source to provide for our energy-dependent society. There has been great interest in scavenging previously unused or wasted energy in a large variety of systems including vibrating machinery, ocean waves and human motion. In this work, a bench-top system of a piecewise-linear nonlinear vibration energy harvester is studied. A similar idealized model of the system had previously been studied numerically, and in this work the method is adjusted to better account for the physical system. This new design is able to actively tune the system’s resonant frequency to match the current excitation through the adjustment of the gap size between the oscillator and mechanical stopper; thus maximizing the system response over a broad frequency range. This design shows an increased effective frequency bandwidth compared with traditional linear systems and improves upon current nonlinear designs that are less effective than linear harvesters at resonance. In this paper, the physical system is tested at various excitation conditions and gap sizes to showcase the new harvester design’s effectiveness.

 
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Award ID(s):
1902408
PAR ID:
10503667
Author(s) / Creator(s):
;
Publisher / Repository:
The Royal Society Publishing
Date Published:
Journal Name:
Proceedings of the Royal Society A: Mathematical, Physical and Engineering Sciences
Volume:
479
Issue:
2277
ISSN:
1364-5021
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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