Particle filter based multisensor fusion for flaw shape reconstruction in steam generator NDE

Determination of flaw profiles from electromagnetic nondestructive evaluation (NDE) measurements is a common inverse problem. There is a strong economic incentive to develop reliable nondestructive evaluation (NDE) methods for steam generator tube inspection. Eddy current inspection has proven to be both fast and effective in detecting and sizing most of the degradation mechanisms that occurred in the early generators. However, as the nation´s generators have aged over years, newer and much more subtle forms of degradation have appeared that require more intelligent application of eddy current tests such as use of multi-frequency eddy current data. A particle filter based multi-sensor fusion technique for NDE signal inversion was proposed for flaw profiling from eddy current NDE data. Preliminary results indicate improvement in the accuracy of inversion results after the employment of data fusion. These results indicate that particle filter based data fusion technique has a potential to achieve high accuracy in flaw profiling when applied to eddy current measurements from steam generator inspection.