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Updated: Aug 5, 2026
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A Polymer-based Piezoelectric Vibration Energy Harvester with a 3D Meshed-Core Structure
Published on: February 20, 2019
Optimal Thickness Shaped Cantilever Type Vibration Energy Harvester for the Second Eigenfrequency
Paulius Skėrys1, Rimvydas Gaidys1
1Department of Mechanical Engineering, Kaunas University of Technology, Studentų g. 56-344, LT-51424 Kaunas, Lithuania.
Micromachines
|July 28, 2026
Summary
Optimizing piezoelectric cantilever beam thickness enhances vibration energy harvesting efficiency by maximizing axial strain at the second eigenfrequency. This shape optimization improves performance under complex excitation conditions.
Area of Science:
- Mechanical Engineering
- Materials Science
- Energy Harvesting
Background:
- Piezoelectric cantilever beams are key vibration energy harvesting devices.
- Maximizing axial strain distribution improves harvesting efficiency.
- The second eigenfrequency is crucial for vibro-impact systems and broadband excitation.
Purpose of the Study:
- To optimize the thickness shape of piezoelectric cantilever beams.
- To maximize axial strain and harvesting efficiency at the second eigenfrequency.
- To enhance energy harvesting performance under realistic operating conditions.
Main Methods:
- A finite element-based optimization scheme was developed.
- The eigenmode equation was used as the state equation.
- Optimization focused on maximizing the strain integral at the second bending resonance, with a fixed second eigenfrequency.
Main Results:
- An optimized thickness shape was determined to maximize axial strain.
- Experimental validation showed increased strain in the optimized beam compared to a uniform beam with the same eigenfrequency.
- The study highlights the importance of shape optimization for practical energy harvesting applications.
Conclusions:
- Thickness shape optimization is an effective strategy for enhancing piezoelectric cantilever beam energy harvesters.
- Optimizing for the second eigenfrequency improves performance under broadband and nonlinear conditions.
- Experimental results confirm the benefits of the optimized design, despite manufacturing and environmental limitations.
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