Summarizing Time-Varying Digital Image Correlation Strain Fields Using Sankey Diagrams

TL;DR

This paper introduces a Sankey diagram-based visualization method to summarize and analyze the evolution of strain fields over time in digital image correlation data, aiding in understanding deformation and failure mechanisms.

Contribution

The authors propose a novel visual summarization technique using Sankey diagrams to represent temporal evolution of strain concentrations in DIC data, enhancing global pattern recognition.

Findings

Effectively captures strain localization and failure precursors.

Distinguishes deformation regimes across different notch geometries.

Provides a compact, global overview of strain evolution.

Abstract

Digital Image Correlation (DIC) enables dense, time-resolved measurement of surface strain in deforming materials, providing insight into strain localization and failure mechanisms. However, the resulting strain fields are typically explored frame-by-frame through spatial visualizations, making global temporal patterns difficult to discern. We present a visual summarization approach that represents the evolution of high-strain regions as a single Sankey diagram constructed from superlevel sets of the von Mises equivalent strain field. By tracking connected components over time via spatial overlap, the diagram encodes the birth, persistence, merging, and disappearance of strain concentrations. Applied to four tensile test datasets with varying notch geometries, the approach compactly captures differences in deformation regimes and qualitative precursors to failure, complementing traditional spatial strain visualizations with a global temporal overview.