PSI - Issue 17

Guillermo Azuara et al. / Procedia Structural Integrity 17 (2019) 774–779 Author name / Structural Integrity Procedia 00 (2019) 000 – 000

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where: • : number of intersection points inside the analysed area; • 2 2 : this term normalizes the exponential function; • : width parameter of the exponential function; • : z-intercept of the correction function; • : weight factor, which depends on the number of paths which cut the intersection point k; and • : relative distance from the junction point ( , ) to the point of analysis ( , ) : ( , , , ) = √( − ) 2 + ( − ) 2 (4) ( , ) = { ( , , , ) ≤ 1 > (5) 4. Results The previously shown results present an inaccurate prediction using standard RAPID algorithm. In order to correct them, the modified algorithm is applied (Figure 6). As an example, the previously selected frequencies were selected to observe the correction.

Figure 6. The pink square is the real location of the damage, and the black point is the predicted location (coordinates in cm). 300 kHz excitation: (a) standard RAPID, (b) modified RAPID. 350 kHz excitation: (c) standard RAPID, (d) modified RAPID.