Development of High-Sensitive Detection and Diagnosis System

点击翻译按钮获取中文摘要

This research has been carried out to develop a high-sensitive detection and diagnosis system in the international joint research program. We have developed various kinds of sensors and detecting methods in the eddy current non-destructive testing (ECT), in order to meet the new goals. As a result, flaw sensitivity and characterization ability in the advanced ECT system developed in this research, were considerably improved in comparison with the conventional ones. Furthermore, coming numerical approach with this measuring method, we have also developed me estimation methods of crack position, shape, and depth. The detailed results were shown in each paper listed in this report. Here we will show you the contents of typical improvements and inventions obtained in this joint research.(1) Magnetic Sensors for Conducting Plates and Tubes:-Rotational magnetic flux type sensors and those differential type probes using a reference plate,-Moving magnetic flux type sensor,-Moving magnetic flux type sensor using shading coil and its differential types,-Matrix type sensors and those differential types.(2) Excitation Methods:-Use of rotational magnetic field to obtain beneficial information in the magnetic flux vector,-Use of moving magnetic field as an inhomogeneous magnetic field,-Use of multi-frequency components to overcome the skin effect (MFES).(3) Numerical Approach (Inverse Problem to Estimate Defects):-Inverse analysis method by BEM with singular value decomposition-Inverse analysis method by BEM with Fuzzy Inference,-Crack identification method with feed-forward neural network.(4) Rotational Barkhausen Signal Including Information of Defects :-New discovery of chaos phenomena in the rotational Barkhausen signals.