Possible issue with 'Re-Measure'
Posted: Sun Mar 08, 2020 9:38 pm
I have noticed some unusual accuracy issues with my LP, when running the re-measure process against fiducials on my PCB.
I believe I have identified a pattern, which may help anyone else with the same issue & code updates if it is a 'bug' of sorts or an incomplete feature.
If I do the following (all on the Run Job tab):
- Home
- re-measure. Visually all 4 Fiducials are identified correctly/accurately, based on camera view.
- Select Fid1 in the CAD Data grid and click the Measured Location Button.
- The cross-hairs on the camera show an offset to the right&up for Fid1
- Clicking the Measured Location on any component also shows a bit of an offset.
However, if I do the following:
- Home
- Manually move to beyond the first Fiducial (Fid1). that is +X & +Y
- re-measure. Visually all 4 Fiducials are identified correctly/accurately, based on camera view.
- Select Fid1 in the CAD Data grid and click the Measured Location Button.
- The cross-hairs on the camera now show Fid1 dead centre in the cross-hairs.
- Clicking the Measured Location on any component also effectively shows centre of each component.
Conclusion:
This behaviour likely explains some of the inconsistent 'accuracy' issues I have been seeing during setup.
It seems that approaching the first Fiducial from -X & -Y at the start of the re-measure...MAY NOT (?) activate the slack compensation or something similar beneath the hood.
If so, it would be a good idea for Juha to add that in.
If not, any suggestions/ideas would be welcome. In the meantime a simple work-around for me is to Home and then manually jog beyond the first Fiducial before clicking the 're-measure' button.
I believe I have identified a pattern, which may help anyone else with the same issue & code updates if it is a 'bug' of sorts or an incomplete feature.
If I do the following (all on the Run Job tab):
- Home
- re-measure. Visually all 4 Fiducials are identified correctly/accurately, based on camera view.
- Select Fid1 in the CAD Data grid and click the Measured Location Button.
- The cross-hairs on the camera show an offset to the right&up for Fid1
- Clicking the Measured Location on any component also shows a bit of an offset.
However, if I do the following:
- Home
- Manually move to beyond the first Fiducial (Fid1). that is +X & +Y
- re-measure. Visually all 4 Fiducials are identified correctly/accurately, based on camera view.
- Select Fid1 in the CAD Data grid and click the Measured Location Button.
- The cross-hairs on the camera now show Fid1 dead centre in the cross-hairs.
- Clicking the Measured Location on any component also effectively shows centre of each component.
Conclusion:
This behaviour likely explains some of the inconsistent 'accuracy' issues I have been seeing during setup.
It seems that approaching the first Fiducial from -X & -Y at the start of the re-measure...MAY NOT (?) activate the slack compensation or something similar beneath the hood.
If so, it would be a good idea for Juha to add that in.
If not, any suggestions/ideas would be welcome. In the meantime a simple work-around for me is to Home and then manually jog beyond the first Fiducial before clicking the 're-measure' button.