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QR code markings, BGA postioning
Posted: Tue Feb 10, 2015 11:52 pm
by Dorijan
1) QR code markings
Since there is already camera installed there could be QR code recognition in which you can describe the part (Value, size, tolerance, farnell number etc.)
2) BGA positioning
if you buy a replacement USB camera for laptop they are very thin.
Slightly unscrewing the lens will change that camera in to macro.
If there is glass over that camera, then your machine could recognize the pin position of the BGA package and precisely put it on the board.
The idea from macro mode is from here:
http://www.raspberrypi.org/macro-photog ... era-board/
3) some of us already have small CNC machines for PCB prototyping, have you considered selling kits with just the P&P parts(vacum pump, cameras etc.)
Re: QR code markings, BGA postioning
Posted: Wed Feb 11, 2015 8:39 am
by JuKu
1) Yes, that could be added. On the other hand, all info a pick and place machine needs is already in the pick and place file.
2) There is an up looking camera already, that could be used. Yet another camera might be beneficial for bigger resolution (enhanced accuracy). There is yet no software for either, though. (As a side thought: I tried to source a flat camera module with reasonable wide angle for needle calibration, but couldn't fine any suitable. If you have one and it looks like an USB camera to the computer, you might avoid having to make a hole in to your table.)
3) You are not the first to ask this. At this point, my top priority is to get the basic kits shipping. So the answer is no, at least not at this point; I might later. (But do you really want a pick and place machine in the same chassis that you have sent small flakes of copper flying around a moment ago?
)
Re: QR code markings, BGA postioning
Posted: Thu Apr 09, 2015 12:10 pm
by PeterST
I tried to source a flat camera module with reasonable wide angle for needle calibration, but couldn't fine any suitable.
Hi Juha,
I may have found one (2592 x 1944) which is 7.8mm of height. However, at this stage of building the machine it is not clear to me what exactly the "specs" for the distance are, except from mentioned x (?) mm under the PCB surface. All I know is that this camera I found requires a minimum distance of 100mm to the object. So now I'm not sure (yet) whether the head can go that high (plus 7.8mm).
If this doesn't suffice I can try to find another one.
Angle of the one I found is 170 degrees.
It's a bit difficult to find the specs all on a single page, but this is the product :
http://www.e-consystems.com/5MP-USB-cameraboard.asp
(mind the OV5640)
About the required noise level, I can't tell ...
Regards,
Peter
Re: QR code markings, BGA postioning
Posted: Thu Apr 09, 2015 12:34 pm
by JuKu
The distance is not very critical, as it affects mainly to image size. During the setup, you'll measure the size of a square the software draws on the image so the image size and therefore the effect of distance is calibrated out. The issue with a flat camera is that the measurements need to be done with the needle at PCB surface level, so there still needs to be some distance from the table to the camera. It would be too much to require that the gantry could be set up so, that it goes perfectly straight down; since it doesn't, the measurements are done with the needle down.
That camera needs 100mm distance from the needle tip when the needle is down, so it is worse than the cameras included. Resolution is great, though. The noise level probably refers to the modules built-in mic.
An angled mirror could work, but the geometry and calibration might get a bit complicated.
Re: QR code markings, BGA postioning
Posted: Thu Apr 09, 2015 1:21 pm
by PeterST
It would be too much to require that the gantry could be set up so, that it goes perfectly straight down; since it doesn't [...]
Aha ... This is quite crucial data.
And actuallly solved nicely.