Weld Electrode Dent Application
FIAT body production lines — automotive quality control
Resistance spot welding is used throughout automotive body production — chassis, hood, doors, roof and rear bumper. With prolonged use the welding electrode tips deform, degrading the three parameters that define weld quality.
When a worn tip's contact surface breaks down, welds become inconsistent and quality drops — followed by time, material and cost losses. This application automatically detects the dent and surface roughness of the tip with image processing.
Weld quality factors
- Weld current graph
- Tip pressure
- Contact surfacethis application
Optical setup
- The weld tip is placed at a 45° angle against the backdrop.
- A line laser hits the tip perpendicular at 45°, illuminating the surface profile as a cross-section.
- The camera faces the backdrop straight on, capturing the tip's slope clearly.
- A polarization filter suppresses reflection noise from the glossy metal surface.
Processing pipeline
Physical setup
Tip 45° — laser 45° — camera 0° — polarization filter
Optics / HardwareImage capture
The profile the laser line draws on the surface is recorded by the camera
OpenCVEdge & dent detection
Deviation of the laser line reveals the dent; edge detection measures it
Python / OpenCVRegression analysis
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MATLAB / PythonReporting & dashboard
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.NET · SQL · JavaScriptFrom the article
