Share Email Print

Proceedings Paper

Characterizing the auto-bispectrum as a detector of nonlinearity in structural systems
Author(s): Jonathan M. Nichols; Attilio Milanese; Pier Marzocca
Format Member Price Non-Member Price
PDF $14.40 $18.00
cover GOOD NEWS! Your organization subscribes to the SPIE Digital Library. You may be able to download this paper for free. Check Access

Paper Abstract

Higher-order spectra (HOS) appear often in the analysis and identification of nonlinear systems. The auto-bispectrum is one example of a HOS and is frequently used in the analysis of stationary structural response data to detect the presence of certain types structural nonlinearities. In this work we use a closed-form expression for the auto-bispectrum, derived previously by the authors, to find the bispectral frequency most sensitive to the nonlinearity. We then explore the properties of nonlinearity detectors based on estimates of the magnitude of the auto-bispectrum at this frequency. We specifically consider the case where the bispectrum is estimated using the direct method based on the Fourier Transform. The performance of the detector is quantified using a Receiver Operator Characteristic (ROC) curve illustrating the trade-off between Type-I error and power of detection (1-Type-II error). Theoretically derived ROC curves are compared to those obtained via numerical simulation. Results are presented for different levels of nonlinearity. Possible consequences are discussed with regard to the detection of damage-induced nonlinearities in structures.

Paper Details

Date Published: 11 April 2007
PDF: 7 pages
Proc. SPIE 6532, Health Monitoring of Structural and Biological Systems 2007, 65320X (11 April 2007); doi: 10.1117/12.715203
Show Author Affiliations
Jonathan M. Nichols, Naval Research Lab. (United States)
Attilio Milanese, Clarkson Univ. (United States)
Pier Marzocca, Clarkson Univ. (United States)

Published in SPIE Proceedings Vol. 6532:
Health Monitoring of Structural and Biological Systems 2007
Tribikram Kundu, Editor(s)

© SPIE. Terms of Use
Back to Top