LitePlacer.com forums

Hi,
I'm under the impression that the bottom vision feature for component alignment is under development. Is this assumption correct?

Kind regards
Michael

Yes and no. I have tried to do that a couple of times, but didn't get good enough results. I found out that to make the feature work, I need to rewrite the vision system more deeply. To be able to do that, some structures in the main program nees to change, most notably how the program data is saved. Besides, there abug fixes already too long in the works. I'm working on these now (new release will come out shortly), after which I'll attack the vision system. Once that is more robust and flexible, I'll return to this.

In other words: Yes, in the sense that it is one of the goals. No, in the sense that I need to take a step or two back and change the route somewhat to reach that goal.

I warm this up again Yesterday I did a long planned experimental approach on bottom vision.
I changed the rmod-fork so that I have a new data field in the tapes, telling me that I need alignment help with the bottom cam.
I can heck that "on" to any tape I like to have bottom vision alignment. I will use that only on bigger parts with more than 4 pins because it takes its time.

After pickup I drive to the cam, lower the nozzle and start a rectangle detection.
I have a red background on the image, a piece of foam with red paper on the nozzle holder, that makes it easier.
With a few filters, I get a really stable image of the QFP44 package I tested with. The vision system gives me the measured middle point as well as the angle, that is used for correction.
Its quite simple, I got it placed perfectly on the pcb Hooray..

I see a few problems with smaller parts, as there is the nozzle visible in the background, that will need some work.
It will also need a few optimization runs as it tries to detect the rectangle, maybe a few tries with different threshold values to adapt to different parts.

I can also use different filter sets for specific parts, that is already selectable in the tapes, every part can have its own filters. To edit these I would add a function to pick a part and hold it over the bottom cam so I can adjsut the filter settings.
Then the machine needs to bring it back in its place.

Soon I have 16 days off, christmas I will work on that and give you the results if it works.