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Updated: Jun 17, 2026
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Using Digital Image Correlation to Characterize Local Strains on Vascular Tissue Specimens
Published on: January 24, 2016
Estimating zero-strain states of very soft tissue under gravity loading using digital image correlation.
1Robotics, Automation, Manipulation, and Sensing Laboratory, University of Maryland, College Park, MD 20742, USA.
Medical Image Analysis
|December 18, 2009
Summary
This study introduces a new method to measure soft tissue mechanical properties during tensile testing. It accounts for gravity
Area of Science:
- Biomechanics
- Materials Science
- Medical Imaging
Background:
- Measuring mechanical properties of soft biological tissues presents challenges due to inherent complexities.
- Gravitational forces can induce pre-compression and non-uniform initial deformation in soft tissues during ex vivo testing.
- Accurate determination of the zero-strain state is crucial for reliable mechanical property analysis.
Purpose of the Study:
- To present experimental techniques for measuring mechanical properties of very soft tissue in ex vivo tensile tests.
- To introduce a novel method for estimating the zero-strain state in soft tissues under tensile load.
- To analyze the influence of gravitational body force on tissue deformation and validate a new analytical approach.
Main Methods:
- Utilized global digital image correlation (DIC) to capture full-field deformation of porcine liver tissue during uniaxial tension.
- Developed and applied a new method to identify the zero-strain state by analyzing the maximum incremental strain.
- Obtained material parameters for the Ogden model by fitting experimental data from ten liver tissue samples.
Main Results:
- Observed a maximum stretching band in the incremental strain field as tissue transitioned from compression to tension.
- Demonstrated that the proposed zero-strain estimation method, based on maximum incremental strain, is effective.
- Finite element simulations confirmed the significant effect of gravity on soft tissue deformation and validated the developed approach.
Conclusions:
- The proposed method for identifying the zero-strain state using maximum incremental strain is robust and applicable to soft tissue analysis.
- Accounting for gravitational effects is essential for accurate mechanical property measurement of very soft tissues.
- The study provides a validated approach for characterizing soft tissue mechanics, with implications for biomedical engineering and research.
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