Single-Camera Three-Dimensional Digital Image Correlation with Enhanced Accuracy Based on Four-View Imaging.

Area of Science:

• Mechanical Engineering
• Materials Science
• Optical Measurement

Background:

• Single-camera 3D digital image correlation (DIC) offers cost-effectiveness and compactness for deformation measurement.
• Traditional methods use diffraction gratings, bi-prisms, or mirrors for dual-view imaging.
• Improving measurement accuracy in single-camera 3D-DIC remains a key research objective.

Purpose of the Study:

• To introduce and validate a novel single-camera four-view 3D-DIC technique.
• To enhance the precision of 3D deformation measurement in materials and structures.
• To reduce random and systematic errors compared to existing dual-view methods.

Main Methods:

• A pyramidal prism was installed in front of a single camera to capture four distinct views.
• Eight governing equations were derived from the four-view geometry for 3D reconstruction.
• Experiments included static, rigid body translation, and four-point bending tests.

Main Results:

• The proposed four-view single-camera 3D-DIC method demonstrated superior measurement accuracy.
• It outperformed traditional dual-view single-camera 3D-DIC techniques.
• Significant reductions in both random and systematic errors were observed.

Conclusions:

• The single-camera four-view 3D-DIC technique provides a more accurate and robust solution for deformation analysis.
• This method leverages strong geometric constraints from multiple views to improve precision.
• It offers advantages for cost-effective and high-accuracy structural and material testing.