As a practical and effective tool for quantitative in-plane deformation measurement of a planar object surface, two-dimensional digital image correlation (2D DIC) is now widely accepted and commonly used in the field of experimental mechanics. It directly provides full-field displacements to sub-pixel accuracy and full-field strains by comparing the digital images of a test object surface acquired before and after deformation. In this review, methodologies of the 2D DIC technique for displacement field measurement and strain field estimation are systematically reviewed and discussed. Detailed analyses of the measurement accuracy considering the influences of both experimental conditions and algorithm details are provided. Measures for achieving high accuracy deformation measurement using the 2D DIC technique are also recommended. Since microscale and nanoscale deformation measurement can easily be realized by combining the 2D DIC technique with high-spatial-resolution microscopes, the 2D DIC technique should find more applications in broad areas.

https://iopscience.iop.org/article/10.1088/0957-0233/20/6/062001/pdf

Two-dimensional digital image correlation for in-plane displacement and strain measurement: a review

Applications of digital-image-correlation techniques to experimental mechanics

Determination of displacements using an improved digital correlation method

Gold, enigmatically represented by the target-like design of its ancient alchemical symbol, has been considered a mystical material of great value for centuries. Nanoscale particles of gold now command a great deal of attention for biomedical applications. Depending on their size, shape, degree of aggregation, and local environment, gold nanoparticles can appear red, blue, or other colors. These visible colors reflect the underlying coherent oscillations of conduction-band electrons (“plasmons”) upon irradiation with light of appropriate wavelengths. These plasmons underlie the intense absorption and elastic scattering of light, which in turn forms the basis for many biological sensing and imaging applications of gold nanoparticles. The brilliant elastic light-scattering properties of gold nanoparticles are sufficient to detect individual nanoparticles in a visible light microscope with ∼102 nm spatial resolution. Despite the great excitement about the potential uses of gold nanoparticles for medical diag...

Gold nanoparticles in biology: beyond toxicity to cellular imaging

Digital image correlation is finding wider use in the field of mechanics. One area of weakness in the current technique is the lack of available displacement gradient terms. This technique, based on a coarse-fine search method, is capable of calculating the gradients. However the speed at which it does so has prevented widespread use. Presented in this paper is the development and limited experimental verification of a method which can determine displacements and gradients using the Newton-Raphson method of partial corrections. It will be shown that this method is accurate in determining displacements and certain gradients, while using significantly less CPU time than the current coarse-fine search method.

Digital image correlation using Newton-Raphson method of partial differential correction

The random nature of white light speckle is combined with newly developed video digital data acquisition procedures to experimentally determine parameters of interest for a rigid body dynamics problem. Digital correlation of subsequent images during a dynamic event is shown to yield displacements and velocities of discrete points in the rigid body and, therefore, the angular velocity and linear velocity of the rigid body.

Application Of Digital Correlation Methods To Rigid Body Mechanics

The application of digital image correlation and stereoscopic principles is used to determine three-dimensional displacements. Two pairs of stereo images of a speckled surface before and after deformation are digitized and correlated to determine the three-dimensional displacements. The images are interpolated so as to account for subpixel displacements. A sequential decision technique and a coarsefine search are employed to increase computer efficiency and decrease run time. Very accurate results are obtained, expecially when the magnification is increased. The effect of camera tilt is shown to be negligible. Theory and experimental verification are presented.

Tsuchin Chu

Papers

Applications of digital-image-correlation techniques to experimental mechanics

Application Of Digital Correlation Methods To Rigid Body Mechanics

Three-dimensional displacement measurements using digital image correlation and photogrammic analysis

Measurement of Whole-Field Surface Displacements and Strain Using a Genetic Algorithm Based Intelligent Image Correlation Method

Noise and Vibration Analysis of a Disc–brake System Using a Stick–slip Friction Model Involving Coupling Stiffness