Share Email Print
cover

Proceedings Paper

Bolt loosening detection using vibration characteristics of thin plate with piezoelectric elements
Author(s): Takeshi Nakahara; Masaaki Yamamoto; Yusuke Ohya; Masaaki Okuma
Format Member Price Non-Member Price
PDF $14.40 $18.00

Paper Abstract

Many researchers have made efforts to develop structural health monitoring methods to detect damages, cracks, corrosion and bolt loosening using modal characteristics of structures. However, modal characteristics are affected by not only damages but also boundary conditions and loading conditions etc. In fact, local damages induce very slight change of modal parameter. Therefore, it will be difficult to apply most of these conventional methods to actual structures. In this paper, we propose a new structural health monitoring method to detect bolt loosening using the characteristics of local vibration modes of a thin plate sensor sandwiched between a bolt, a nut and washers in main structures. This sensor consists of a thin plate and some piezoelectric elements. In local mode vibration of the thin plate sensor, the bolt’s axial tension determines its boundary condition. Bolt loosening changes the boundary condition and natural frequencies of the sensor. However, main structure’s characteristics don’t affect sensor’s modal characteristics. Since our method attempts using local vibration modes it is important to distinguish the local vibration modes of interest from the global ones related to structures. We propose a technique to distinguish local modes using finite element method. Finally, we confirm the validity of the thin plate sensor experimentally.

Paper Details

Date Published: 29 July 2004
PDF: 12 pages
Proc. SPIE 5391, Smart Structures and Materials 2004: Sensors and Smart Structures Technologies for Civil, Mechanical, and Aerospace Systems, (29 July 2004); doi: 10.1117/12.538389
Show Author Affiliations
Takeshi Nakahara, Tokyo Institute of Technology (Japan)
Masaaki Yamamoto, Tokyo Institute of Technology (Japan)
Yusuke Ohya, Tokyo Institute of Technology (Japan)
Masaaki Okuma, Tokyo Institute of Technology (Japan)


Published in SPIE Proceedings Vol. 5391:
Smart Structures and Materials 2004: Sensors and Smart Structures Technologies for Civil, Mechanical, and Aerospace Systems
Shih-Chi Liu, Editor(s)

© SPIE. Terms of Use
Back to Top