Universal Robots UR5e: A fixed camera, small presentation changes, very different streaks

DineshBennett0734 · 17 Apr 2026, 19:20 UTC

Reply to discussion
DI
DineshBennett0734
We're planning checking cosmetic metal surfaces with a fixed camera, with Universal Robots UR5e presenting a bright-finished enclosure faceplate to a fixed camera in a cosmetic components workshop. Bright streaks move with small presentation changes in our example images, but people keep calling them scratches. We haven't commissioned the cell. How do i sort the references and imaging before we tune thresholds around this mess?

21 replies

YA
YasminAdams0093
Replying to DineshBennett0734

Were those scratches confirmed on the physical samples using your agreed appearance method? Start by linking each image to a sample and its inspection result

16 points
DI
DineshBennett0734
Replying to YasminAdams0093

@YasminAdams0093 Some labels came from the pictures alone. We still have the samples, but those labels aren't tied to physical inspection results. That's irritatingly circular.

20 points
YA
YasminAdams0093
Replying to DineshBennett0734

Mark those labels uncertain and have the samples inspected properly. Then compare images with presentation and lighting controlled; the moving streaks are a useful reflection clue

6 points
JA
JamieBrown0904
Replying to YasminAdams0093

A scratch's visibility can change with presentation too. Don't let 'moving streak' quietly become the rule for relabelling something acceptable

10 points
YA
YasminAdams0093
Replying to JamieBrown0904

Correct. I meant a reason to investigate the imaging, not a new defect label. Physical acceptance stays with the agreed inspection method

20 points
CL
ClaraAdams0089
Replying to YasminAdams0093

@YasminAdams0093 Should uncertain images be treated as acceptable, or kept somewhere separate while their status is established?

17 points
YA
YasminAdams0093
Replying to ClaraAdams0089

Retain their sample identities and undecided status. They shouldn't become confirmed acceptable or defective examples while the physical review remains unresolved

7 points
DI
DineshBennett0734
Replying to YasminAdams0093

Our two comparison folders changed exposure and presentation together. i can't tell which change made the images look better. That comparison needs a caveat too.

10 points
LU
LuisBrooks0869
Replying to DineshBennett0734

I had a separate inspection setup where the 'better lighting' folder used easier samples too. Its name implied a lighting conclusion that the comparison didn't support.

13 points
DI
DineshBennett0734
Replying to LuisBrooks0869

What did you keep beside each image? i can manage sample ID and settings, but i don't want a form nobody fills in.

17 points
LU
LuisBrooks0869
Replying to DineshBennett0734

For my separate setup, sample identity, exposure, lighting arrangement and presentation condition were the useful essentials. They let us understand comparisons without relying on recollection.

15 points
YA
YasminAdams0093
Replying to LuisBrooks0869

Use those details to ask your vision specialist for controlled comparisons on representative surfaces. Keep the sample set fixed when assessing an acquisition change

14 points
CL
ClaraAdams0089
Replying to YasminAdams0093

Could using a learned inspection model remove the need to resolve the lighting variation?

15 points
YA
YasminAdams0093
Replying to ClaraAdams0089

It still needs trustworthy labels and representative evaluation. A different model doesn't establish whether your reference scratches are real or your acquisition comparison is fair

6 points
JA
JamieBrown0904
Replying to YasminAdams0093

And don't tune and test on different pictures of the same physical sample. That isn't the independence the result would suggest

13 points
DI
DineshBennett0734
Replying to JamieBrown0904

@JamieBrown0904 i'll group images by physical sample before dividing the tuning and evaluation sets. The current filenames wouldn't reliably expose the same sample appearing in both.

21 points
YA
YasminAdams0093
Replying to DineshBennett0734

Report missed defects and false rejects separately on the held-out samples. One agreement percentage can hide which mistake your method is making

6 points
DI
DineshBennett0734
Replying to YasminAdams0093

Should undecided physical samples count as misses in that report? i don't want them quietly disappearing just because they're awkward.

3 points
YA
YasminAdams0093
Replying to DineshBennett0734

Report the undecided samples and their number explicitly, but don't include them as confirmed-class errors. This preserves the coverage limitation without assigning an unestablished reference label

12 points
DI
DineshBennett0734
Replying to YasminAdams0093

@YasminAdams0093 i've settled the review method: physical reference checks plus controlled image comparisons. That answers where to start; whether our inspection concept is suitable still depends on the resulting evaluation.

4 points

Add to the discussion

Welcome to Application Robot

Everyone can read the forum. Sign in or create an account to start a discussion, reply, or upload photos.

Forgot your password?

By creating an account, you agree to our Terms and Conditions and community guidelines. Read our Privacy Policy for how your information is handled.