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A Method for Measuring Parameters of Defective Ellipse Based on Vision
He Zhang1,2, Li Wang1,2, Wenya Liu1,2
1Center of Ultra-Precision Optoelectronic Instrument, Harbin Institute of Technology, Harbin 150080, China.
Sensors (Basel, Switzerland)
|July 29, 2023
Summary
This study presents a vision-based method for rapid ellipse detection in defective parts. The technique accurately fits ellipse parameters, enhancing geometric size detection for industrial applications.
Area of Science:
- Computer Vision
- Geometric Measurement
- Industrial Inspection
Background:
- Ellipse detection is crucial for object recognition, particularly for geometric analysis of defective industrial components.
- Existing methods struggle with feature defects, leading to slow and inaccurate detection.
Purpose of the Study:
- To develop a rapid, vision-based method for accurately determining defective ellipse parameters.
- To improve upon existing ellipse detection techniques that are time-consuming and prone to errors.
Main Methods:
- Utilizes the circle approximation principle to repair defective circular features.
- Employs morphological processing to identify effective edge points.
- Applies the least squares method for precise ellipse parameter estimation.
Main Results:
- Simulated defect ellipses showed center fitting errors under 1 pixel and axis fitting errors under 3 pixels.
- Simulated tilt angle fitting error was less than 0.1°.
- Experimental validation on engine injection holes yielded size deviations < 0.01 mm and angle errors < 0.15°.
Conclusions:
- The proposed method enables quick and effective acquisition of defective ellipse parameters.
- Demonstrates suitability for engineering applications, including precise measurement guidance for fiber probes.
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