An iterative algorithm for eddy current signal inversion

Liu, Guizhong; Li, Yue; Sun, Y.; Sacks, P.; Udpa, S.
May 2000
AIP Conference Proceedings;2000, Vol. 509 Issue 1, p497
Academic Journal
This paper presents an iterative algorithm for investing eddy current NDE signals. The objective of this work is to estimate parameters characterizing defect size and shape, based on information contained in the measured eddy current signals. The approach uses the Finite Element Method (FEM) to model the physical process. The parameters of the forward model are updated using an iterative scheme that minimizes the sum of the squared errors between the measured and FEM predicted signals. The cost function is minimized by updating the defect profile parameters. The conjugated gradient method is used to arrive at the minima in the multi-dimensional search space. Simulation results, obtained using axisymmetric test geometries, demonstrate the effectiveness of the approach. © 2000 American Institute of Physics.


Related Articles

  • Lagrangian analysis by clustering. Koszalka, Inga Monika; LaCasce, Joseph H. // Ocean Dynamics;Aug2010, Vol. 60 Issue 4, p957 

    We propose a new method for obtaining average velocities and eddy diffusivities from Lagrangian data. Rather than grouping the drifter-derived velocities in geographical bins, we group them by nearest-neighbor distance using a clustering algorithm. This yields sets with approximately the same...

  • Structural synthesis of attachable eddy-current probes with a given distribution of the probing field in the test zone. Gal�chenko, V.; Vorob�ev, M. // Russian Journal of Nondestructive Testing;Jan2005, Vol. 41 Issue 1, p29 

    A method for designing attachable eddy-current probes with a given spatial distribution of the probing field is proposed. This method is based on a structural synthesis implemented using a genetic algorithm. An example of the numerical solution for the synthesis of a local cylindrical probe is...

  • PEC: Computation of coil-induced voltage due to a defect-free plate using Stehfest's method for pulsed eddy current evaluation. Mengbao Fan; Binghua Cao; Yuqiao Wang // Insight: Non-Destructive Testing & Condition Monitoring;Jun2010, Vol. 52 Issue 6, p302 

    The pulsed eddy current technique has demonstrated considerable promise as a new tool for the evaluation of conducting plate structures. Recently, much attention has been paid to the Laplace transform-based method for the calculation of transient probe response. However, use of the Laplace...

  • Pulsed Eddy Current Measurement of Lift-Off. Lefebvre, J. H. V.; Mandache, C. // AIP Conference Proceedings;2006, Vol. 820 Issue 1, p669 

    It is observed that the slope of pulsed eddy current signals at the Lift-Off point of Intersection (LOI) depends strongly on the lift-off. The behaviour of the LOI slope is studied under varying test conditions. The signal response is curve-fitted to a circuit equivalent non-linear model using...

  • Real-time pre-processing of the pulsed eddy current signal from continuous casting slabs. Qiu, Xuanbing; Wei, Chao; Cui, Xiaochao; Wei, Jilin // Insight: Non-Destructive Testing & Condition Monitoring;Mar2013, Vol. 55 Issue 3, p136 

    Both the software and hardware of a pulsed eddy current (PEC) real-time testing device are designed to pre-process the noise from continuous casting slabs (CCS) during in situ defect detection. An algorithm based on a sliding window with a fixed length is developed in the process of denoising....

  • Real-Time Determination of the Position and Shape of the Plasma Column from External Magnetic Measurements in the GLOBUS-M Tokamak. Amoskov, V.M.; Belyakov, V.a.; Bender, S.E.; Gusev, V.K.; Kavin, A.A.; Lamzin, E.A.; Levin, R.G.; Sadakov, S.N.; Sakharov, N.V.; Sychevski&icaron;, S.E.; Filatov, O.G. // Plasma Physics Reports;Dec2003, Vol. 29 Issue 12, p997 

    A fast algorithm is elaborated for determining the position and shape of the plasma column from measurements performed with magnetic probes located outside the vacuum vessel of the GLOBUS-M tokamak. The algorithm is based on the modeling of the plasma current by movable current filaments and...

  • Experience in developing and using automated laser diagnostic equipment for the contactless monitoring of the parameters of freight car wheels. Baibakov, A.; Kuchinskii, K.; Paterikin, V.; Plotnikov, S.; Sotnikov, V. // Measurement Techniques;Apr2010, Vol. 53 Issue 4, p444 

    The problems of obtaining high reliability in the automated contactless monitoring of the geometric parameters of freight car wheels during the motion of a train under practical operating conditions using laser equipment are discussed. The factors which influence the reduction in the monitoring...

  • Eddy current mapping inside a plane conductor with flaws. Ribeiro, A. Lopes; Ramos, H. Geirinhas; Pasadas, D. J.; Rocha, T. J. // AIP Conference Proceedings;Jan2013, Vol. 1511 Issue 1, p428 

    When a constant field probe with sinusoidal excitation is used to detect flaws inside a conductor, the lines of current must be uniform in a limited area under the influence of the constant excitation field. The existence of flaws inside the metallic material forces the current to deviate from...

  • GPU based numerical modeling for eddy current non-destructive evaluation. Lei, Naiguang; Udpa, Lalita; Udpa, Satish // AIP Conference Proceedings;Jan2013, Vol. 1511 Issue 1, p644 

    Numerical models serve an important role in eddy current non-destructive evaluation applications. The results of computational models provide meaningful insight into the underlying physics, help theoretically visualize the field/sample interaction and help optimize sensor design and assist...


Read the Article


Sorry, but this item is not currently available from your library.

Try another library?
Sign out of this library

Other Topics