Advancement of Optical Methods & Digital Image Correlation in Experimental Mechanics

2021 ◽  
2017 ◽  
Vol 61 (1) ◽  
pp. 21-36 ◽  
Author(s):  
ZhenXing Hu ◽  
TingGe Xu ◽  
XueMin Wang ◽  
ZhiMing Xie ◽  
HuiYang Luo ◽  
...  

2014 ◽  
Vol 136 (2) ◽  
Author(s):  
Jeffrey D. Pyne ◽  
Katia Genovese ◽  
Luciana Casaletto ◽  
Jonathan P. Vande Geest

Optic nerve head (ONH) deformations may be involved in the onset or further development of glaucoma, including in patients with relatively normal intraocular pressures (IOPs). Characterizing posterior scleral deformations over physiological pressures may provide a better understanding of how changes in IOP lead to changes in the mechanical environment of the ONH and possibly retinal ganglion cell death. Pressure inflation measurement test protocols are commonly used to measure deformation of the peripapillary sclera with full-field noncontact optical methods. The purpose of this work was to develop and validate a new sequential 3D digital image correlation (S-DIC) approach for quantification of posterior scleral pressure induced deformation that improves z (in-depth) resolution of the DIC measurement without losing in-plane sensitivity, while also being able to contour and map deformations of the complex-shaped ONH. Our approach combines two orthogonal axes of parallax with standard 3D DIC methods using a single high-resolution camera. The enhanced capabilities of S-DIC with respect to standard 3D DIC has been demonstrated by carrying out a complete benchmark for shape, deformation, and strain measurement on an object of known complex geometry. Our S-DIC method provided a reconstruction accuracy of 0.17% and an uncertainty in z-position measurement of 8 μm. The developed methodology has also been applied to a human posterior scleral shell, including the full peripapillary sclera and optic nerve. The relatively inexpensive S-DIC approach may provide new information on the biomechanical deformations of the optic nerve head and, thus, the death of retinal ganglion cells in primary open angle glaucoma.


1985 ◽  
Vol 25 (3) ◽  
pp. 232-244 ◽  
Author(s):  
T. C. Chu ◽  
W. F. Ranson ◽  
M. A. Sutton

2018 ◽  
Vol 68 (2) ◽  
pp. 61-76 ◽  
Author(s):  
Miroslav Pástor ◽  
Peter Frankovský ◽  
Martin Hagara ◽  
Pavol Lengvarský

AbstractAnchoring parts of technical systems are often damaged due to the heavy forces acting on these systems during their operation. For that reason, various modifications are suggested and created on the anchoring screws, which should help to reduce the mechanical stress values in a place of the first load-bearing thread of a female screw. For the determination of stress fields on the surface of a plane model of a threaded joint, two non-contact optical methods were used – conventional transmission photoelasticimetry and modern digital image correlation.


2018 ◽  
Vol 36 ◽  
pp. 03003 ◽  
Author(s):  
Janusz P. Kogut ◽  
Marcin Tekieli

Non-contact video measurement methods are used to extend the capabilities of standard measurement systems, based on strain gauges or accelerometers. In most cases, they are able to provide more accurate information about the material or construction being tested than traditional sensors, while maintaining a high resolution and measurement stability. With the use of optical methods, it is possible to generate a full field of displacement on the surface of the test sample. The displacement value is the basic (primary) value determined using optical methods, and it is possible to determine the size of the derivative in the form of a sample deformation. This paper presents the application of a non-contact optical method to investigate the deformation of coarse soil material. For this type of soil, it is particularly difficult to obtain basic strength parameters. The use of a non-contact optical method, followed by a digital image correlation (DIC) study of the sample obtained during the tests, effectively completes the description of the behaviour of this type of material.


2020 ◽  
Vol 10 (4) ◽  
pp. 1530 ◽  
Author(s):  
Jean-Noël Périé ◽  
Jean-Charles Passieux

Digital Image Correlation (DIC) has become the most popular full field measurement technique in experimental mechanics [...]


2013 ◽  
Vol 486 ◽  
pp. 141-146
Author(s):  
Martin Hagara ◽  
František Šimčák ◽  
Matúš Kalina

These days are preferably used contactless optical methods for experimental investigation of strains and displacements, which give some information on whole investigated surface. In this contribution the optical systems working on electronic speckle pattern interferometry (ESPI) principle and digital image correlation (DIC) method are described. By using of ESPI and DIC methods the displacements and strains fields on chosen types of specimens are determined. Pros and cons of particular methods and influence of various factors on reached results accuracy are compared. There are also mentioned the possibilities of using of optical methods in application of devices on authors department.


Sign in / Sign up

Export Citation Format

Share Document