A MODEL-BASED AUTOFOCUS ALGORITHM FOR ULTRASONIC IMAGING USING A FLEXIBLE ARRAY

Research output: Chapter in Book/Report/Conference proceedingConference Contribution (Conference Proceeding)

Abstract

Autofocus is a methodology for estimating and correcting errors in the assumed parameters of an imaging algorithm. It provides improved image quality and, therefore, better defect detection and characterization capabilities. In this paper, we present a new autofocus algorithm developed specifically for ultrasonic non-destructive testing and evaluation (NDE). We consider the estimation and correction of errors in the assumed element positions for a flexible ultrasonic array coupled to a specimen with an unknown surface profile. The algorithm performs a weighted least-squares minimization of the time-of-arrival errors in the echo data using assumed models for known features in the specimen. The algorithm is described for point and planar specimen features and demonstrated using experimental data from a flexible array prototype.

Original languageEnglish
Title of host publicationREVIEW OF PROGRESS IN QUANTITATIVE NONDESTRUCTIVE EVALUATION, VOLS 29A AND 29B
EditorsDO Thompson, DE Chimenti
Place of PublicationMELVILLE
PublisherAmerican Institute of Physics (AIP)
Pages863-870
Number of pages8
ISBN (Print)978-0-7354-0748-0
Publication statusPublished - 2010
Event36th Annual Review of Progress in Quantitative Nondestructive Evaluation - Kingston, Jamaica
Duration: 26 Jul 200931 Jul 2009

Conference

Conference36th Annual Review of Progress in Quantitative Nondestructive Evaluation
CountryJamaica
CityKingston
Period26/07/0931/07/09

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