Magneto-optic=eddy current imaging (MOI) is becoming widely used for aging aircraft
inspection for cracks and corrosion. However, many test parameters affect the accept=reject
decision about a test sample and hence the overall performance of MOI system. The
optimization of the parameters is extremely crucial in enhancing the performance of MOI
system. This article uses the Taguchi method to change parameter values simultaneously to
search for the optimum set of test parameters for maximizing system performance for a
given sample geometry and critical crack. It is also important at the same time the system
performance be unaffected by variations in parameters. Efficiency of Taguchi’s partial factorial
design is obvious. The optimum set of parameters is found by means of analyses of
main effects. Analysis of variance identifies those parameters that need to be controlled
carefully. A response-model approach is utilized as a complement to the Taguchi method.
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