A Measurement Method for Large Parts Combining with Feature Compression Extraction and Directed Edge-Point Criterion

Area of Science:

• Aerospace Engineering
• Metrology
• Computer Vision

Background:

• Accurate measurement of large aviation components is critical for high-quality aircraft assembly.
• Boundary measurement results are key parameters in aviation part metrology.
• Existing methods may face challenges in achieving high accuracy for large-scale parts.

Purpose of the Study:

• To propose an accurate measurement method for the surface and boundary of aviation parts.
• To enhance the precision of both surface and boundary measurements for large components.
• To achieve high-precision reconstruction of aerospace parts.

Main Methods:

• Combines global boundary extraction with local laser stripe feature analysis.
• Utilizes a sub-pixel centroid extraction method based on image compression for accurate laser stripe center identification.
• Employs a directed arc-length criterion for precise edge-point extraction to define the boundary.

Main Results:

• Achieved high-accuracy surface and boundary measurement of large aviation parts.
• The proposed method demonstrated a mean distance deviation of 0.47 mm in physical measurements.
• Field experimentation validated the effectiveness and applicability of the developed method.

Conclusions:

• The developed feature compression extraction and directed edge-point criterion method enables high-precision reconstruction of aerospace parts.
• The method offers improved accuracy and efficiency for measuring large aviation components.
• Experimental results confirm the practical validity and reliability of the proposed measurement technique.