Table of Contents
Smart Materials Research
Volume 2012, Article ID 287128, 9 pages
http://dx.doi.org/10.1155/2012/287128
Research Article

Comparison of Analog and Digital Self-Powered Systems in Multimodal Vibration Suppression

1Institute of Space and Astronautical Science (ISAS), Japan Aerospace Exploration Agency (JAXA), 3-1-1 Yoshinodai, Chuo-Ward, Sagamihara, Kanagawa 252-5210, Japan
2Department of Aerospace Engineering, Tohoku University, 6-6-01 Aoba, Aramaki, Aoba-Ward, Sendai 980-8579, Japan

Received 14 December 2011; Accepted 15 January 2012

Academic Editor: Ma Jan

Copyright © 2012 Shigeru Shimose et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Abstract

This paper compares our analog and digital self-powered systems for vibration suppression, and shows experimental results of multimodal vibration suppression for both self-powered systems. The experimental results are evaluated in light of the damping performance and adaptability under various vibrational conditions. We demonstrate various examples of our innovative vibration suppression method, called “digital self-powered.” Proper status switching of an electric circuit made up of an inductor and a selective switch connected to a piezoelectric transducer attenuates the vibrations. The control logic calculation and the switching events are performed with a digital microprocessor that is driven by the electrical energy converted from the mechanical vibration energy. Therefore, this vibration suppression system runs without any external power supply. The self-powering feature makes this suppression method useful in various applications. To realize an ideal vibration suppression system that is both self-powered and effective in suppressing multimode vibration, sophisticated control logic is implemented in the digital microprocessor. We demonstrate that our digital self-powered system can reduce the vibrational displacements of a randomly excited multimodal structure, by as much as 35.5%.