This Article Full Text (OnlineFirst PDF) Alert me when this article is cited Alert me if a correction is posted Services Email this article to a friend Similar articles in this journal Alert me to new issues of the journal Add to Saved Citations Download to citation manager Request Permissions Request Reprints Add to My Marked Citations Google Scholar Articles by Erturk, A. Articles by Inman, D. J Social Bookmarking                   What's this?

On Mechanical Modeling of Cantilevered Piezoelectric Vibration Energy Harvesters

¹ Department of Engineering Science and Mechanics
² Department of Mechanical Engineering, Center for Intelligent Material Systems and Structures, Virginia Tech Blacksburg, VA 24061, USA

^* To whom correspondence should be addressed.

	Abstract

Cantilevered beams with piezoceramic (PZT) layers are the most commonly investigated type of vibration energy harvesters. A frequently used modeling approach is the single-degree-of-freedom (SDOF) modeling of the harvester beam as it allows simple expressions for the electrical outputs. In the literature, since the base excitation on the harvester beam is assumed to be harmonic, the well known SDOF relation is employed for mathematical modeling. In this study, it is shown that the commonly accepted SDOF harmonic base excitation relation may yield highly inaccurate results for predicting the motion of cantilevered beams and bars. First, the response of a cantilevered Euler–Bernoulli beam to general base excitation given in terms of translation and small rotation is reviewed where more sophisticated damping models are considered. Then, the error in the SDOF model is shown and correction factors are derived for improving the SDOF harmonic base excitation model both for transverse and longitudinal vibrations. The formal way of treating the components of mechanical damping is also discussed. After deriving simple expressions for the electrical outputs of the PZT in open-circuit conditions, relevance of the electrical outputs to vibration mode shapes and the electrode locations is investigated and the issue of strain nodes is addressed.

Key Words: energy harvesting, mechanical modeling, base excitation, damping, strain nodes.

CiteULike    Connotea    Del.icio.us    Digg    Reddit    Technorati    What's this?