On the optimal bending deflection of piezoelectric scavengers

Abstract

This study aims at exploring the possibility to optimize the electromechanical efficiency of piezoelectric cantilevers by imposing an optimal deflection to classical rectangular devices, rather than designing non-conventional geometries. Focusing on non-vibrating loading conditions, the proposed approach is to apply a constant bending moment to the beam in order to reach the maximum allowable stress on the whole outermost surface. This is realized in practice by pressing the cantilever over a cylindrical-shaped support. Theoretical and numerical models with electromechanical coupling are developed to evaluate the performance improvement compared to the deflection of a classical tip-load configuration. Finally, experimental tests have been performed to further verify the electrical power enhancement given by the proposed optimized layout.

Keywords

Energy harvesting piezoelectric bending deflection

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References

Ajitsaria

Choe

Shen

Kim

(2007) Modeling and analysis of a bimorph piezoelectric cantilever beam for voltage generation. Smart Materials & Structures 16: 447–454.

Anton

Sodano

(2007) A review of power harvesting using piezoelectric materials. Smart Materials & Structures 16: R1–R21.

Baker

Roundy

Wright

(2005) Alternative geometries for increasing power density in vibration energy scavenging for wireless sensor networks. In: 3rd International energy conversion engineering conference, AIAA San Francisco, CA, 15–18 August 2005.

Benasciutti

Moro

Zelenika

Brusa

(2010) Vibration energy scavenging via piezoelectric bimorphs of optimized shapes. Microsystem Technologies 16: 657–668.

Brown

AAD

(1981) Mechanical Springs (Engineering Design Guides, 42). Oxford University Press.

Costa Branco

Dente

(2004) On the electromechanics of a piezoelectric transducer using a bimorph cantilever undergoing asymmetric sensing and actuation. Smart Materials & Structures 13: 631–642.

Erturk

Inman

(2008) Issues in mathematical modelling of piezoelectric energy harvesters. Smart Materials & Structures 17: 065016.

Erturk

Inman

(2009) An experimentally validated bimorph cantilever model for piezoelectric energy harvesting from base excitations. Smart Materials & Structures 18: 025009.

Goldschmidtboeing

Woias

(2008) Characterization of different beam shapes for piezoelectric energy harvesting. Journal of Micromechanics and Microengineering 18: 104013.

10.

Kopmaz

Gündoğdu

(2003) On the curvature of an Euler-Bernoulli beam. International Journal of Mechanical Engineering Education 31: 132–142.

11.

Kusculuoglu

Fallahi

Royston

(2004) Finite element model of a beam with a piezoceramic patch actuator. Journal of Sound Vibration 276: 27–44.

12.

Lim

Soh

(2001) Three-dimensional electromechanical responses of a parallel piezoelectric bimorph. International Journal of Solids and Structures 38: 2833–2849.

13.

Lee

Lim

(2004) Modeling and analysis of micro piezoelectric power generators for micro-electromechanical-systems applications. Smart Materials & Structures 13: 57–63.

14.

Mateu

Moll

(2005) Optimum piezoelectric bending beam structures for energy harvesting using shoe inserts. Journal of Intelligent Material Systems and Structures 16: 835–845.

15.

Maurini

Pouget

Dell’Isola

(2006) Extension of Euler-Bernoulli model of piezoelectric laminates to include 3D effects via a mixed approach. Computers & Structures 84: 1438–1458.

16.

Okayasu

Ozeki

Mizuno

(2010) Fatigue failure characteristics of lead zirconate titanate piezoelectric ceramics. Journal of the European Ceramic Society 30: 713–725.

17.

Shenck

Paradiso

(2001) Energy scavenging with shoe-mounted piezoelectrics. Micro IEEE 21: 30–42.

18.

Timoshenko

(1940) Strength of Materials, Part 2. Van Nostrand: New York.