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The three most important new features

Posted: Wed Jan 16, 2019 3:01 pm
by robert@serve101.org
I recently went for a factory visit to a SMD shop. The professional machines of today are truly amazing. The speed and accuracy are breathtaking. But then I passed through the final inspection station, even with these professional machines, some rework is needed. After that I was feeling better about the microscope time I put in before melting the paste.

So I started wondering what are the three most important upgrades owners of the liteplacer have on their wish list. I wonder if we agree on a list? Let me start this off with my top three, please add your own list to this thread.

1) I would like there to be a better way to manage the component parts to be placed. I struggle with it taking too much time to get my parts ready. Plus, sometimes parts "leap" out of their little tape holes when an adjunct part is selected. Or sometimes, I make mistakes, and the machine tries to pickup from an empty spot. Or sometimes, the parts just do not get picked up at all and then the nozzle ends up with paste in it.

2) More use of the up facing camera. I find the accuracy of parts placement can be reasonable if a lot of effort goes into making everything go just right. Surface tension helps a lot though. And a bit of non-alignment of a resistor does not really affect the functionality. But the board just looks beautiful when the parts are "perfectly" placed. So I would like the up facing camera to be used to be able to adjust for better placement. Another owner reported doing so makes a big difference in accuracy. Another use of the up camera, would be to determine and compensate for the Z axis movement not being perfectly vertical. And speaking of cameras, I wish we had better ones, where I could adjust the focus without changing the center of vision. Why is the down facing camera need such a large mounting angle to look straight down?

3) I would like the documentation to be improved. For example, when/how are various values saved? How can I set up my machine so clicking on the image moves the camera cross-hairs to the clicked on location? This may be my fault for not being a good enough reader of the docs, but after more than a year of using the machine, I find there are still so many details I do not really know or understand.

I find the liteplacer to be a great machine, worth many times over the price charged. I also appreciate that the design in open source, although I have not yet contributed anything to the code package. The speed of the machine meets my needs, since I tend only build only a few boards at a time.

Re: The three most important new features

Posted: Sat Jan 19, 2019 6:17 pm
by ds23man
I think this forum is dead as a Dodo.....

Re: The three most important new features

Posted: Sat Jan 19, 2019 9:55 pm
by Jet
robert@serve101.org wrote:I struggle with it taking too much time to get my parts ready.
This is fairly common with any pick and place machine. There's some jobs where it's so small, or a one off where the setup time is more than doing it by hand. OpenPNP has a slightly faster workflow for this.
robert@serve101.org wrote:Plus, sometimes parts "leap" out of their little tape holes when an adjunct part is selected.
This is typically due to shock from the nozzle hitting the surface too hard (reduce the deceleration rate) and also is due to flex in the tape. If the tape has something to prevent it from flexing or is taped securely to the surface along the length, it doesn't happen.
robert@serve101.org wrote: Or sometimes, I make mistakes, and the machine tries to pickup from an empty spot. Or sometimes, the parts just do not get picked up at all and then the nozzle ends up with paste in it.
The solution here is vacuum detection, to detect the part on the nozzle. OpenPnp has support for this and the Liteplacer machine is easily modified to add it (I'm just about to do just that today). Also Up vision helps to some extent if you have the vision setup correct in OpenPnp, i.e. it will detect a part is missing. The vacuum detection in this case is just a bonus to detect it earlier and in case the up vision doesn't detect it correctly, which happens occasionally with up vision alone on small parts like 0402's. A good insurance against a plugged nozzle.
robert@serve101.org wrote: 2) More use of the up facing camera. I find the accuracy of parts placement can be reasonable if a lot of effort goes into making everything go just right. Surface tension helps a lot though. And a bit of non-alignment of a resistor does not really affect the functionality. But the board just looks beautiful when the parts are "perfectly" placed. So I would like the up facing camera to be used to be able to adjust for better placement. Another owner reported doing so makes a big difference in accuracy.
It does and is fully supported with OpenPnP.
robert@serve101.org wrote: Another use of the up camera, would be to determine and compensate for the Z axis movement not being perfectly vertical.
You can remove that issue by making sure the top of the pcb, bottom of the component are all the same height. (and the height of the component is setup). Not available in Liteplacer software yet but currently available in OpenPnP
robert@serve101.org wrote: And speaking of cameras, I wish we had better ones, where I could adjust the focus without changing the center of vision. Why is the down facing camera need such a large mounting angle to look straight down?
That would be nice, autofocus would be good.
robert@serve101.org wrote: 3) I would like the documentation to be improved. For example, when/how are various values saved? How can I set up my machine so clicking on the image moves the camera cross-hairs to the clicked on location? This may be my fault for not being a good enough reader of the docs, but after more than a year of using the machine, I find there are still so many details I do not really know or understand.
I found the assembly documentation to be good, and the hello world / calibration documentation okay. I didn't struggle too much with it. What would have been useful is a high accuracy tuning guide / troubleshooting and an overview of pick and place machines and how inaccuracy in alignment is dealt with through the various techniques used.

It should be considered that although Juha created the machine, he doesn't get a lot of time to use it or develop the software as he's shipping so many kits.

I.E. It's a good quality hackers kit, where some learning will be required and some figuring out yourself. The mechanical design itself is quite good for the price.

I purchased the machine in Apr 2017, built it, found it wasn't accurate enough, left it, went back, found the same, I've been trying to get something workable on and off with it for about 20 months, until I switched to OpenPnP and realized that part of the issue was the Liteplacer software (for my needs, for other's placing larger components it's fine). Since I did that, I'm placing 0402's accurately, high pin count QFP's and bga's accurately and now I'm using the machine and building up my library of parts.

Bottom line, for accuracy, and things like vacuum detection, part recognition, up camera support, vision etc., OpenPnP accels on all of these over the Liteplacer software currently. The only thing I'm missing from the Liteplacer software is the machine limits. Juha does have improvements planned, but currently OpenPnp is the solution with this machine IMHO, I also find the workflow more intuitive, it's also better supported due to the very large and active community. There was a time when OpenPnp had some difficulties running on a Liteplacer machine, but all these issues have since been solved.

The vision is particularly impressive, I'll randomly put anything that's not capacitor or resistor in a tray, and OpenPnp will pick out the part and figure out the rotation on it with the Advanced Loose Part Feeder, you just train it once with the image of a part, and input the area of the part if you really want to make sure it picks the correct one. So setup becomes easier. For resistors / caps you pick from tape, for anything else, if it's a number of parts in plastic tape, you'd probably setup the tape due to the quantity, otherwise any parts that appear visually different from each other, tip into an area or tray and let the vision system pick it up.

I'd be for Juha making his life easier by doing an EOL on the Liteplacer Software and switching his setup instructions to OpenPnp. It's a big waste of that development work to date, but given the development going forward and available time, it has to be easier path.

Then reason I took so long to switch away from the Liteplacer Software was because I thought "that's the software that was written for the machine", so figured it would work better.

Not knocking Juha's work, an obvious amount of effort went into that software, and with further work it could easily exceed OpenPnP.
ds23man wrote:I think this forum is dead as a Dodo.....
Really?

Re: The three most important new features

Posted: Sun Jan 20, 2019 12:19 pm
by ds23man
Jet wrote:
ds23man wrote:I think this forum is dead as a Dodo.....
Really?
Well, I posted several questions on this forum about 3D files for tape feeders, no replies. Pm'd a member here about the 3D files of a feeder tray ( sells it on Ebay), one read other still sitting in my outbox, also no replay. I posted something about an interesting dragfeeder from a Chinese machine, no reply.

Re: The three most important new features

Posted: Sun Jan 20, 2019 6:56 pm
by Jet
ds23man wrote:
Jet wrote:
ds23man wrote:I think this forum is dead as a Dodo.....
Really?
ds23man wrote:Well, I posted several questions on this forum about 3D files for tape feeders, no replies. Pm'd a member here about the 3D files of a feeder tray ( sells it on Ebay), one read other still sitting in my outbox, also no replay. I posted something about an interesting dragfeeder from a Chinese machine, no reply.
Just because you don't get a reply immediately, doesn't mean the forum is dead. It could mean, nobody was interested in your post yet, for example I already read your post, but didn't
reply because it doesn't fit my requirements, I'm probably going to design my own ultimately.

Also, some people don't have notifications for posts they've replied to switched on, and don't check back frequently (for example I only
check every few days depending on what I've posted recently). So PM'ing the person or finding other contact means if that isn't working would be an approach.

It's also good to realize that people are under no obligation to reply to you, they may have other commitments, or can't find the files anymore and will dig them out when they have time, or the PM ending up in spam. Maybe try the info contact address on that website and see if you have more luck there and ask if you can post the link back to the forum so others can benefit from your effort.

This for sure is a low volume forum so people check back less frequently, but there is activity. If you want more forum activity, switch over to OpenPnP (that's the other extreme, too much :-) )

Re: The three most important new features

Posted: Tue Jan 22, 2019 6:17 pm
by wormball
Jet wrote:The only thing I'm missing from the Liteplacer software is the machine limits.
So openpnp can not set machine limits? Sounds stupid. However the tinyG have $xTN and $xTM commands which i think do the same.
Jet wrote:If you want more forum activity, switch over to OpenPnP (that's the other extreme, too much )
Unfortunately it is in rather inconvenient form of mailing list.

Re: The three most important new features

Posted: Wed Jan 23, 2019 7:22 pm
by Jet
wormball wrote: So openpnp can not set machine limits? Sounds stupid. However the tinyG have $xTN and $xTM commands which i think do the same.
It's not too big a deal, unless you Jog manually in the wrong direction, and yes $xTN and $xTM address that. The benefits of OpenPnp over
Liteplacer software (in it's current state), far outweigh any downside. It's nice to have a usable machine being actively used and placing small components accurately.
wormball wrote:Unfortunately it is in rather inconvenient form of mailing list.
Also accessible via the web as a list, exactly the same as this forum.

Re: The three most important new features

Posted: Thu Jan 24, 2019 7:54 am
by ds23man
My list:

1. Bottom vision
2. Bottom vision
3. Bottom vision
4. Vacuum sensing.
5. Drag feeder option with the nozzle or a separate solenoid mounted at the back of the head.

I hope Juha can shed some light on his development, maybe a roadmap?

Re: The three most important new features

Posted: Mon Jan 28, 2019 4:36 pm
by ds23man
The biggest problem in this moment is some health issues Juha has ( mentioned it here: https://liteplacer.com/phpBB/viewtopic. ... 9433#p9433). His last post dates 27 december and he has been offline from 23 jan till today.

Re: The three most important new features

Posted: Tue Jan 29, 2019 4:57 pm
by ds23man
Did send a mail to Yuha yesterday, no reply. Something is wrong.