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  • Application of Digital Image Correlation to the Local Strain Analysis of Mouse Aortas: Novel Method to Create Speckle Pattern
Title: Application of Digital Image Correlation to the Local Strain Analysis of Mouse Aortas: Novel Method to Create Speckle Pattern
Digital image correlation (DIC) is a non-destructive and non-contact optical technique to measure deformation and strain of materials. The method is based on optically tracking the displacements of a speckle pattern created on the material surface. In the case of soft tissues such as mouse aorta, there are several advantages to using DIC since it can provide local, rather than global, deformations and it is suitable for large strain measurements, typical of soft tissues taken to failure [1] [2]. For the optimal use of DIC, several requirements should be met for speckle patterning: 1) randomness, 2) high contrast, 3) appropriate size of speckle in the field of view (3-5 pixels), and 4) firm attachment of speckle to specimen during deformation. In previous DIC studies of soft tissues, the methods employed to create a speckle pattern include the use of an airbrush to spray dye or paint on the specimen, or coating the sample with toner powder. However, biological samples must be partially dehydrated before applying paint which may affect the mechanical properties of the specimen, and toner powder is too hydrophobic to adhere well on specimens when submerged in aqueous solution during mechanical testing. In addition, it is difficult to evenly distribute paint or toner powder on the surface of a hydrated biological specimen [2]. Therefore, a novel method utilizing colloidal gold particles to create a speckle pattern on mouse aorta is proposed in this work.  more » « less
Award ID(s):
1760906
PAR ID:
10104068
Author(s) / Creator(s):
; ; ;
Date Published:
Journal Name:
Proceedings of the 2019 Summer Biomechanics, Bioengineering, and Biotransport Conference
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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