Accurate Reconstruction of High-Gradient Strain Field in Digital Image Correlation: A Local Hermite Scheme

2018 ◽  
pp. 173-175
Author(s):  
Xin Li ◽  
Jiaqing Zhao ◽  
Jianguang Shuai ◽  
Zhengming Zhang ◽  
Xinxin Wu
Keyword(s):  
Digital Image Correlation ◽  
Digital Image ◽  
Strain Field ◽  
Image Correlation ◽  
High Gradient ◽  
Accurate Reconstruction

Methodology for in situ stress intensity factor determination on cracked structures by digital image correlation

2010 ◽  
Vol 1 (4) ◽  
pp. 344-357 ◽  
Author(s):  
V. Richter‐Trummer ◽  
P.M.G.P. Moreira ◽  
S.D. Pastrama ◽  
M.A.P. Vaz ◽  
P.M.S.T. de Castro
Keyword(s):  
Stress Intensity Factor ◽  
Stress Intensity ◽  
Digital Image Correlation ◽  
Intensity Factor ◽  
Digital Image ◽  
Strain Field ◽  
Image Correlation ◽  
Content Type ◽  
Cracked Structures

PurposeThe purpose of this paper is to develop a methodology for in situ stress intensity factor (SIF) determination that can be used for the analysis of cracked structures. The technique is based on digital image correlation (DIC) combined with an overdetermined algorithm.Design/methodology/approachThe linear overdeterministic algorithm for calculating the SIF based on stress values around the crack tip is applied to a strain field obtained by DIC.FindingsAs long as the image quality is sufficiently high, a good accuracy can be obtained for the measured SIF. The crack tip can be automatically detected based on the same strain field. The use of the strain field instead of the displacement field, eliminates problems related to the rigid body motion of the analysed structure.Practical implicationsIn future works, based on the applied techniques, the SIF of complex cracked plane stress structures can be accurately determined in real engineering applications.Originality/valueThe paper demonstrates application of known techniques, refined for other applications, also the use of stress field for SIF overdeterministic calculations.

scholarly journals A new methodology to identify minimum strain anatomical lines based on 3-D digital image correlation

2017 ◽  
Vol 8 (2) ◽  
pp. 337-347 ◽  
Author(s):  
Jorge Barrios-Muriel ◽  
Francisco Javier Alonso Sánchez ◽  
David Rodríguez Salgado ◽  
Francisco Romero-Sánchez
Keyword(s):  
Digital Image Correlation ◽  
Digital Image ◽  
Strain Field ◽  
Three Dimensional ◽  
Wearable Devices ◽  
Plane Motion ◽  
Human Motion ◽  
The Body ◽  
Image Correlation ◽  
Minimum Deformation

Abstract. Today there is continuous development of wearable devices in various fields such as sportswear, orthotics and personal gadgets, among others. The design of these devices involves the human body as a support environment. Based on this premise, the development of wearable devices requires an improved understanding of the skin strain field of the body segment during human motion. This paper presents a methodology based on a three dimensional digital image correlation (3D-DIC) system to measure the skin strain field and to estimate anatomical lines with minimum deformation as design criteria for the aforementioned wearable devices. The errors of displacement and strain measurement related to 3-D reconstruction and out-of-plane motion are investigated and the results are acceptable in the case of large deformation. This approach can be an effective tool to improve the design of wearable devices in the clinical orthopaedics and ergonomics fields, where comfort plays a key role in supporting the rehabilitation process.

Identification of the Mechanical Properties of High-Strength Steel Using Digital Image Correlation

2014 ◽  
Vol 980 ◽  
pp. 122-126 ◽  
Author(s):  
Michaela Štamborská ◽  
Miroslav Kvíčala ◽  
Monika Losertová
Keyword(s):  
Mechanical Properties ◽  
Digital Image Correlation ◽  
Digital Image ◽  
High Strength Steel ◽  
Strain Field ◽  
High Strength ◽  
Image Correlation ◽  
Uniaxial Tensile ◽  
Large Strains ◽  
Identification Procedure

Identification of the mechanical properties of high-strength steel using digital image correlation. In this paper an experimental procedure to identify the plastic behaviour of sheet metals up to large strains using full field measurement is presented. The tests were conducted on notched specimens. This geometry generates a heterogeneous strain field which was measured during the test using a digital image correlation system. The advantage of using a heterogeneous strain field in the identification procedure is that a complex state of stress-strain can be analyzed at the same time and much more information can be obtained in a single test. On the other hand, the stress field cannot be directly computed from the test and a suitable identification procedure must be developed. Here, the virtual fields method (VFM) adapted for large strains and plasticity was used to identify the hardening behaviour and the anisotropy of the material. The values obtained with the VFM were compared with the results from a standard identification made using uniaxial tensile tests.

Sign in / Sign up

Export Citation Format

Share Document