Digital image correlation

About: Digital image correlation is a research topic. Over the lifetime, 7842 publications have been published within this topic receiving 132166 citations.

Method and apparatus for measuring motion of a subject using a series of partial images from an imaging system

Abstract: A line scan imager is used to determine the motion of a subject. Each line of image data from the line scan imager is compared with a reference image. The location of a matching line in the reference image reveals the displacement of the subject. The current subject displacement can be determined based on each line of image data. The resulting displacement information can be used to correctly place other optical beams on the subject. The method can be applied to tracking the human eye to facilitate measurement, imaging, or treatment with a beam of optical radiation.

Simulation of the global response of a friction stir weld using local constitutive behavior

Abstract: The local and global mechanical responses of friction stir welded AA-2024 were studied experimentally and modeled using the finite element technique. A technique employing tensile testing and digital image correlation was used to obtain the full field strain distribution in transversely loaded welds, as well as the local constitutive behavior of the various weld regions. Two-dimensional, plane stress and plane strain, finite element models of the welded specimen were constructed using the local constitutive properties as input data and the local and global responses in tension were simulated. Nearly plane stress conditions were found to exist in the specimen as demonstrated by the correspondence between experimental results and the predictions of the 2-D models. These findings were further corroborated by use of a 3-D finite element model. The 3-D model was also used to examine the constraint developed in specimens of various widths.

Real-time 3D digital image correlation method and its application in human pulse monitoring.

Abstract: In industrial measurements and online monitoring, full-field and high-efficiency deformation analysis has been increasingly important and highly demanded in recent years. In this paper, a fast three-dimensional digital image correlation (3D-DIC) method was proposed to implement real-time measurement. Two improvements were suggested to accelerate the computation speed without sacrificing the accuracy. First, an efficient inverse compositional Gauss-Newton (IC-GN) algorithm was developed to avoid redundant computation. Moreover, a seed point-based parallel method was extended for 3D-DIC to achieve parallel computation and faster convergence speed. The detailed process of the real-time measurement using the proposed method was also introduced. Benefiting from the efficient IC-GN algorithm and parallel processing software we developed, full-field, real-time 3D deformation monitoring was realized at a frame rate of 10 frames/s with resolution of 5000 points per frame. For validation, the displacement field of a four-point bending beam was determined by the real-time 3D-DIC. As an application, the real-time human pulse diagnosis was also performed based on the presented technique. Experimental results verify that the proposed real-time 3D-DIC is practicable and effective for traditional Chinese medicine.