Homing after nozzle change

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korsm...@gmail.com

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Sep 11, 2023, 7:37:08 AM9/11/23
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Hi,

Can openpnp be set that it performs a homing after nozzle change? However accurate I set everything (PS the speed setting does nothing in the nozzle bank) i get the feeling that after a nozzle change, some settings are off.

At the end of most of my PCB's. it takes a bigger nozzle and start placing the chips. I would love that it would do:
- Take a now nozzle.
- Home cycle (how?)
- Calibrate nozzle
- Perform a fiducial check again (how??)
- place (with vision) the chip(s).

So also, is there a setting to perform for certain xomponents an extra fiducial check.. I always thought there was, but cna not find it.

Accuracy is more important than speed for me....

mark maker

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Sep 11, 2023, 8:46:38 AM9/11/23
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Hi,

First you should really, really try to solve the underlying issue. The only reason I see for that behaviour would be the steppers losing steps in the changer motion. There are tons of things to check, like stepper current, more precise load/unload motion capture, making the loader more "permissive" by adding flex etc.

Maybe changer vision can help make the changing motion more precise:
https://github.com/openpnp/openpnp/wiki/Nozzle-Tip-Changer#vision-calibration

Video about changer vision (among other stuff):
https://youtu.be/9uFxV1-vnXw

Also make sure to enable nozzle tip calibration after each nozzle tip change.

If all else fails, you could add a visual homing through the

NozzleTip.Loaded

script. Something like that (draft pseudo code à la Java):

ReferenceHead head = (ReferenceHead)Configuration.get().getMachine().getDefaultHead();
head.visualHome(head.getMachine(), true);

I would not recommend full homing, just visual homing, as full homing resets too much.

_Mark
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korsm...@gmail.com

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Sep 12, 2023, 6:27:21 AM9/12/23
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Hi Mark,

I am going to try to optimise it with your tips.. Thanks.. But, to be sure, I still want to add the homing..
maybe I just do not have the best motors or card, but also bought it secondhand a long time ago.. I would like a new card, because I also miss vaccuum recognition (I have all the parts but the wrong gcode card it seems).

Ayway,  I am searching but where can i find the part where i can input the nozzletip. loaded section? I am going through the program and the XML configuration files but I have no clue where to find it.. Sorry for asking maybe a stupid question (and yes, they do exist :) ) 

PS, I am a vb programmer so Java is completely liek a foreign language.. No clue at all... :).




Op maandag 11 september 2023 om 14:46:38 UTC+2 schreef ma...@makr.zone:

mark maker

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Sep 12, 2023, 6:53:58 AM9/12/23
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korsm...@gmail.com

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Sep 12, 2023, 7:38:04 PM9/12/23
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Hi Mark,

Thanks for the good and fast input.. I did not know of the scripts but that is nice... while I do not know anything about Java, it was not easy but I managed.
I used:
 ReferenceHead = machine.getDefaultHead();
ReferenceHead.visualHome(machine,true);


Op dinsdag 12 september 2023 om 12:53:58 UTC+2 schreef ma...@makr.zone:
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