Suggestions for a PCB automatic optical inspection machine.

[procidaj]

Hello Everyone,

I am looking to purchase an AOI for PCB inspection.  Its intended use is not for a production facility but more of a research facility, so it will definitely be low volume usage. 

Currently I am looking at a NovaScope NS-1818 or a NS1818-AV.  If anyone has any suggestions for an alternative or any experience using this piece of equipment id really appreciate it!

[SMTech]

First things first, that is not an AOI. It doesn't even claim to be an AOI, its not even a comparator. It is a first article inspection aid, of some sort. Its clearly not as useful as a quins, which does no analysis, but alternates the images of each region between golden sample and UUT to help your brain. It makes no attempts at interpreting the image like the scanner based aoisystems might (these aren't AOI machines either as, like your camera the image is pure 2D top down which is less helpful than you might think). It is merely a robotic camera, better than nothing but not about to rock your world vs a magnifier or inspection camera with no robot.

I think you need to define a few things.

• What are you trying to inspect?
• What faults are you expecting to catch?
• What is your budget?
• What space do you have?
• Where are you?

There are any number of FAI machines, they cost anything  between £10K and £25K, however around that 25K point you can buy an entry level 2D AOI such as the prey merlin https://ascinternational.com/wp-content/uploads/2021/05/Prey-Merlin-AOI-2021-1-003.pdf. These use angled light sources to fake up a 3D interpretation of your solder fillets. As Far as I am concerned, its not AOI until it can do at least this, otherwise all it can catch is missing/skewed/shouldn't be there and wrong part if you're lucky.

For a little less than something like a Merlin, assuming you can get a decent price for shipping you could choose something direct from China.

Moving up the food chain, commercial low volume production models from MEK or Aleader or an entry level Mirtec. This bit of the market is interesting as most of them have actually abandoned 2D+angled light inspection and moved to 3D inspection. This helps you because it means people who have upgraded, might be selling their old AOI cheap. Here's a UK example https://www.shawline.co.uk/category.php?id_category=10 the benchtop Marantz in that picture is £4k, the Nordson is £13k but also risky as I understand if you wanted support, of any kind there's a massive "product registration" fee, this is not uncommon and something to look out for.

[procidaj]

After rereading the quote from the company I see what you mean now about the First Article Inspection.  Perhaps that's the recommendation that I am looking for.

To answer your questions though:
1. In house assembled printed circuit boards.
2. Missing components, tombstone caps and resistors, solder joints for through holes, and IC orientation would be the most the basic needs.  Anything extra would be a bonus, I've seen photos of AOI machines that make a 3D image and can show if a pin is raised up on something like a HDMI connector.
3. We were quoted 25k for the NS-1818 and 40k for the NS-1818-AV which the only difference seems to be angle view cameras and red, green, and blue side lighting.
4. Space wise we dont need anything large.  Like I said it will be used for low volume, probably less then 20 boards a week on average.
5. New York

Thank you for the information you already provided.  The merlin link will be a good starting point for me to do some further research into this.

[SMTech]

OK, so missing, skewed, polarity, case markings those are things you can catch with machines based around flatbed scanners and these should include software to automate and record the process. The most affordable and simple one I have come across and had demo'd is this one from AOI Systems http://www.aoisystems.com/Scanner-Based-FA-Inspector.html . AOI systems are a small Scottish team to my understanding, but spend a lot of time in the US. The other interesting option in this category is the AgnosPCB camera based system which can probably spot similar faults but purely based on comparison.

What these types of systems cannot do is any level of inspection of a solder joint as the flat image doesn't give the software any information as to how much solder is present. That is what the angled light would perhaps be trying to help you with on the 1818-AV but its still relying your monkey brain to decide good vs bad. To my mind the 1818 is way overpriced.

On 2D AOi systems like the Merlin, those colored lights at different angles are used to build up a histogram and from there an indication as to the 3D profile is derived. A totally flat unsoldered surface will be seen as bright white, a steep edge blue etc etc. MEK Powerspektor can add multiple cameras to this view to turn it into a 3D image. They call this "selective 3D" as its not that practical to deploy across an entire PCB and also not as useful as you might expect.

Some 3D systems deploy multiple angled cameras (e.g Yamaha) some use one or more lasers and some like Omron/Koh Yung  use "Moiré interferometry" or phase shifting to try and mitigate things like shadowing that affect a pure vision based system. They are all true production systems and very expensive.

[Jackster]

OK, so missing, skewed, polarity, case markings those are things you can catch with machines based around flatbed scanners and these should include software to automate and record the process. The most affordable and simple one I have come across and had demo'd is this one from AOI Systems http://www.aoisystems.com/Scanner-Based-FA-Inspector.html . AOI systems are a small Scottish team to my understanding, but spend a lot of time in the US.

I was going to try one of these as I found a used one for cheap.
Called AOIsystems and asked if it was still supported and they said that any support for the machine, including software updates, would be £10,000.

[procidaj]

Thank you so much for the thorough response and recommendations. I will talk to my boss about this next week and provide any updated information.

[SMTech]

OK, so missing, skewed, polarity, case markings those are things you can catch with machines based around flatbed scanners and these should include software to automate and record the process. The most affordable and simple one I have come across and had demo'd is this one from AOI Systems http://www.aoisystems.com/Scanner-Based-FA-Inspector.html . AOI systems are a small Scottish team to my understanding, but spend a lot of time in the US.

I was going to try one of these as I found a used one for cheap.
Called AOIsystems and asked if it was still supported and they said that any support for the machine, including software updates, would be £10,000.

Pretty funny given it was £12k+VAT in 2021 a price that was pretty similar ~10 years before that.

[Calder]

The other interesting option in this category is the AgnosPCB camera based system which can probably spot similar faults but purely based on comparison.

I need to clarify that it’s not an image comparator—it actually understands what it’s seeing, like a technician would. We’ve been using this company’s system (AgnosPCB) for about two years now (approx.), and we recently switched to their new machine, but that’s another story. The key point is that it doesn’t compare pixels. I can assure you of that.

Sometimes the PCBA or the panel we pull out for inspection has differences in the silk layer, shifts in the dissipation holes, dust, or small surface variations (logos, text, tiny scratches, etc.). You know how it is. Those variations are not flagged as errors by AgnosPCB’s AOI. We save a lot of time because of that.

Recently, we asked for a system adaptation so it could also detect whether certain potentiometers were correctly adjusted. Now the AOI lets us know if that’s the case.

[XxMandragoraxX]

Wow that sounds great, I'm doing a chain production of some projects that I want to carry out.

If I send you a photo taken of my PCBA, can you analyze it with your system to see what it shows?

[SMTech]

The other interesting option in this category is the AgnosPCB camera based system which can probably spot similar faults but purely based on comparison.

I need to clarify that it’s not an image comparator—it actually understands what it’s seeing, like a technician would. We’ve been using this company’s system (AgnosPCB) for about two years now (approx.), and we recently switched to their new machine, but that’s another story. The key point is that it doesn’t compare pixels. I can assure you of that.

Sometimes the PCBA or the panel we pull out for inspection has differences in the silk layer, shifts in the dissipation holes, dust, or small surface variations (logos, text, tiny scratches, etc.). You know how it is. Those variations are not flagged as errors by AgnosPCB’s AOI. We save a lot of time because of that.

Recently, we asked for a system adaptation so it could also detect whether certain potentiometers were correctly adjusted. Now the AOI lets us know if that’s the case.

These days, even inspection cameras come with "AI" or other "ML" tools that mean they "understand" and interpret what they are seeing. However unless Agnos is very different from when I last looked at it, its still "comparing" to a golden sample. Not to an innate knowledge of what an 0805 resistor looks like or any database of parts or packages or any knowledge of what the parts are on the board. So no not a pixel by pixel comparator (which would be flat out useless) but its still inspection by comparison, the knowledge is.. that the square blocks of colour are the things whose presence and angle it should analyse? The use of a fixed overhead camera is an inherent weakness that reduces its effective resolution on larger boards and it shares the other limitations inherent in every pure 2D top down system. It is still a cool tool, it clearly has very handy uses in certain scenarios but its an alternative approach answering different questions. It would be interesting to see an evolution of this software put in a scanner based system or even a 2D with laser&/angled light system. Add in the BOM knowledge etc that those systems typically have and you'd have another new product. To my knowledge all the lower end AOI systems are essentially hardcoded algorithm based systems with user parameters. ML/AI is only in the newest and most expensive models

[XxMandragoraxX]

From what I saw on their website and on YouTube, they have a new version called the 4050 platform that has an inspection area of ​​40x50 cm and has a moving head with an XY system and has autofocus with a Z axis, with which They make stiching of the photos you take of the plates. The truth is that it looks good.




Has anyone tested this machine or the software? I would like to have a review or something for reference, it's not bad if they do what they say

[SMTech]

From what I saw on their website and on YouTube, they have a new version called the 4050 platform that has an inspection area of ​​40x50 cm and has a moving head with an XY system and has autofocus with a Z axis, with which They make stiching of the photos you take of the plates. The truth is that it looks good.




Has anyone tested this machine or the software? I would like to have a review or something for reference, it's not bad if they do what they say

It does look a step doesn't it. The price is also climbing   To my mind this makes a Quins even more difficult to justify, every time I have looked at Quins I wonder why they have so rigidly stuck to not trying to use at least some automated analysis .

With this kind of purchase the ideal situation is to get hands on yourself with product you want to inspect. When Agnos was new we tried the whole demo it using a phone and the results were not great but indicative of a good idea. Equally at the time a good enough internet connection wasn't even an option at our premises. I suspect that last one remains an issue for many, and the offline version is big step up in price, its nice the price is at least visible now.

We have looked at various inspection systems on and off for the last 15 years. We've had demos at shows, demos on site, demos online & never quite taken the plunge. A conventional AOI machine takes time to "tune" it needs to learn the packages you use, the geometry of your pads etc so it can dial that it against what you consider acceptable or the IPC standard you are following. That said on-site demos have detected and shown us things on our own assemblies almost immediately and that includes things that we thought were fine and inspected manually with a camera would pass inspection and functional test. These assemblies would also have been accepted by something like the AOISystems platform because the issue was typically printing and those systems cannot measure that.

Understanding where your production issues are is key to choosing your equipment, and not just the inspection system. For us, knowing we had a weakness in printing beyond fine pitch being more challenging (and frankly I'd rate my manual printing output as pretty good compared to the garbage I see on Youtube) was important. Our inspection system needed to be at least that capable, and by extension was pretty pointless unless we addressed printing first. A review is nice for many things but they unless they contain decent context and hard figures, basically meaningless for a product like this.

[SMTech]

This caught my eye, one of the systems on demo at an upcoming UK show: Parmi 3D AOI with AI Programming Software – Experience how quickly a program can be created without any data input—a truly game-changing development

I have no idea what model this feature it applies to, or how much of an extra $$$$ feature it is, but it sounds interesting. I understand one of Parmi's models is basically a slowed down version of the other to let them sell it for less but otherwise basically feature comparable. That model is still 80k+ or something but that is I think quite competitive for 3D AOI, certainly a lot less than rough estimates I have had for Omron,Pemtron& even Aleader.

The real problem with any system is they are not optimal with small batches, a small batch or prototype might mean there is no golden sample for something like Agnos and not enough samples to really dial in an AOI.

[XxMandragoraxX]

Wow, I've been looking at Parmi 3D AOI and it looks good, but what happens is that it is a machine for a much more industrial environment than mine. I only do small production runs in my small business and work locally where I live, but I would like to make the same device repeatedly, hence the inspection machine.

For this reason AgnosPCB seems more accurate to me and more what I need, apparently it is just inserting the board and scanning, you don't have to do anything else, much faster. Also the online version is not as expensive, compared to the Parmi 3D AOI

[SMTech]

Wow, I've been looking at Parmi 3D AOI and it looks good, but what happens is that it is a machine for a much more industrial environment than mine. I'm just a hobbyist and I do work locally where I live, but I would like to make the same device repeatedly, hence the inspection machine.

For this reason AgnosPCB seems more accurate to me and more what I need, apparently it is just inserting the board and scanning, you don't have to do anything else, much faster. Also the online version is not as expensive, compared to the Parmi 3D AOI

The Agnos probably has a very strong case for keeping an eye on small batch builds that probably have a significant chunk of human involvement. This is why its important to understand what you are looking to inspect and the errors you want to catch. If I have placed 50 PCB's with 100% automation, a missing part is rare and a reversed diode/tant/elec basically impossible; an IC maybe if it flipped in the tube exit or Farnell repacked the tube without keeping every IC the same way around (common). So for me Agnos isn't the tool for my 50+ batches, but it might be for a single stage such as pre reflow on complex boards or tiny batches.