This paper answers some performance and calibration questions about a non-destructive-evaluation (NDE) procedure that uses artificial neural networks to detect structural damage or other changes from sub-sampled characteristic patterns. The method shows increasing sensitivity as the number of sub-samples increases from 108 to 6912. The sensitivity of this robust NDE method is not affected by noisy excitations of the first vibration mode. A calibration procedure is proposed and demonstrated where the output of a trained net can be correlated with the outputs of the point sensors usded for vibration testing. The calibration procedure is based on controlled changes of fastener torques. A heterodyne interferometer is used as a displacement sensor for a demonstration of the challenges to be handled in using standard point sensors for calibration.

Date Published: 10 November 2003
PDF: 10 pages
Proc. SPIE 5191, Optical Diagnostics for Fluids, Solids, and Combustion II, (10 November 2003); doi: 10.1117/12.501265

Published in SPIE Proceedings Vol. 5191:
Optical Diagnostics for Fluids, Solids, and Combustion II
Patrick V. Farrell; Fu-Pen Chiang; Carolyn R. Mercer; Gongxin Shen, Editor(s)