Small scale AOI option?

[Rat_Patrol]

Is there a small scale or light DIY AOI option out there?

[SMTech]

There's  a cloud based one linked on here somewhere - basically a pretty decent image comparison engine using your phone camera or Pi for example.  https://www.agnospcb.com/ Tried it very briefly, decided we wanted to tweak setup/workflow a bit, haven't got round to it...

Around £10k there are multiple options of what are typically called FAI (first article inspection) machines based on scanners, strictly 2D so they have limitations, there are at least 4 built and sold in the UK, I would imagine there must be many others, a European example would be a Quinns which in some ways does less than some.

Step up to £20k and you get something between AOI and FAI, a few more algorithms, maybe even the beginnings of 2.5D using different coloured light at different angles. However that stage really kicks in around £40k for a proper entry level desktop AOI unit, but that's from a trained supportive reseller selling a Chinese machine, so in theory it should be possible to find that class of machine for less direct.

[Mangozac]

I did some experimenting with a Raspberry Pi and OpenCV a few years back but it didn't eventuate to much. The major takeaway was that if any kind of speed was needed you need a better processor.

I would like to have a simple check for missing or tombstoned components when boards come out of the oven and I feel that such a system could be created without too much difficulty. The most important part would be creating a well diffused light source that provides repeatable captures. Obviously this doesn't pick up on all potential soldering failures but between this and a functional test 99.9% should be covered.

[nisma]

Ti works, you need either modified flatbead CCD scanner with big field of focus or fast stepper driven belt with reduction. Rpi and v1 camera + separate PC.

[SMTech]

I did some experimenting with a Raspberry Pi and OpenCV a few years back but it didn't eventuate to much. The major takeaway was that if any kind of speed was needed you need a better processor.

I would like to have a simple check for missing or tombstoned components when boards come out of the oven and I feel that such a system could be created without too much difficulty. The most important part would be creating a well diffused light source that provides repeatable captures. Obviously this doesn't pick up on all potential soldering failures but between this and a functional test 99.9% should be covered.

Minor tombstones/dry joints will get right past a 2D scanner based system and have a pretty good chance of getting past a functional test too. Floating inputs have unpredictable states, and missing decouplers probably don't matter on your test bench. Still better than a pair of tiring eyes of course but still not something you could rely on.

[Rat_Patrol]

Dry joints is what I'm primarily worried about.

The smallest components I generally work with are 1206 and SOT23, with the occasional 0805 thrown in to keep things interesting: all large enough to easily see a missing/tombstone component.

I suppose I'll keep on with manual inspecton/testing for now until I can increase the budget.

[SMTech]

No idea on availability outside the UK but expanding on previous....
http://www.aoisystems.com/products.html, these claim to spot tombstone and I have seen it demo'd on site but it was a long time ago, probably time for another Demo tbh.

http://www.dcbautomation.com/ these were much more impressive than the above, roving camera, angled colored lights, good price, laser options for more 3D-ness.

https://detech-europe.com/aoi-systems/detech-aoi-systems/ looks a bit like the previous one, vague on capabilities.

http://optimumtechnical.co.uk/wp-content/uploads/2017/06/AOI-Bochure_Web.pdf another cheapy, seen it at a show, its basically a comparator, a bit like the cloud option I mentioned but with a nicer interface/workflow than you get with uploading images to a webpage. This took a little longer to scan & analyse its demo PCB to present us with the areas we might want to look at than a proper ALeader AOI system took to 100% scan and analyse a PCB and TELL us what was wrong with it. That extra 30K does buy you quite a bit of the A bit of AOI.

The key with any system is to have a false Pass rate that is as low as possible, false fails are annoying but don't damage your reputation.

There are a few DIY AOI attempts online, mostly they seem to boil down to inspection assistants, but SOT23 and 1206 should present almost no issues anyway, maybe thats enough. In the UK the first example would spread the cost over 1 months quite happily. You might find older examples around, they were called Yestek for a while until YesTech gave them a slap.

There is a german system somewhere where you buy the software for €5k and the scanner bit is seperate/optional......

[Calder]

I am late to the party, but consider AgnosPCB as an option. Small inspection platform footprint.

[Reckless]

I have a Mirtec MV7XI for sale.  Its an inline AOI but awesome software.  Will give a great deal on it, located in Chicago.