Component picking errors

[ianh]

Hi,
I have recently been seeing an issue with the picking of components from the tape.  When I calibrate the feeders the position is correct, but over time the pick position moves to the right (away from the bed of the machine), I then re-calibrate the pick, and again it drifts right.  This seems to affect all the feeders.
The component placement does not drift though.
Has anyone experienced this?  Any ideas to the reason and what the fix would be.

I have checked the component advancement of the feeders and this is always correct (It affects multiple feeder banks anyway, so unlikely to be a feeder issue)

[Mike]

By default, it will adjust the pick position based on vision results to home in on the optimal position.
This can be disabled using the "lock feeders" options in the part CDF.
Not sure why this would cause a global drift but might be worth trying to see if locking makes a difference.
And of course make sure the feeder is solidly locked down to the baseplate!

[ianh]

Thanks Mike,

I have determined that it does get worse the more components placed, and that in lanes that have not been used then the offset does not happen - so your point about it moving the pick position based on vision results is a good possibility.
How can that be calibrated out?  it could be that the vision isn't calibrated correctly, this uses the 'on the fly' camera (0603 parts) - how do you calibrate that camera.

I will select the 'lock feeders' option in the CDF files for the 0603 parts I am using to see if this improves things.
Regards,
Ian.

[ianh]

HI Mike,

That seems to have fixed the immediate problem.  I have since observed that the imaging of the component using the on the fly camera generally reports the X position as +15 (+12 to + 18) even though the component is positioned centrally on the pick-up tool.  How can I correct this offset.

But, the placement of the part on the PCB is not indicating any X shift - it seems to be placing correct X position.  So, this begs a question, if the camera is saying the part is +15 off, but places correctly, then there must be a board offset or some other factor that then compensates for this apparent +15 offset.

Any help or clarification you can offer on how these various offsets work would be greatly appreciated.

[Mike]

Take a look in the factory setup menu - there are some camera adjustments there, don't recall offhand what though.
Also try using teh fixed camera to verify that it's a camera issue ( Force fixed in CDF) 
Also check that the mirror isn't loose.

[ianh]

Thanks Mike.
Using the calibration routine for the camera seems to have fixed the issue.

I assume I calibrated it correctly, I manually placed the large pick tool (the one with the while ring) on the nozzle and then clicked on the calibrate button.