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A.O.I - no salesman pitch pls



A.O.I - no salesman pitch pls | 9 June, 2003

With mounting interest in the "Automated Optical Inspection" thread revolving around SMTnet, was wondering from a end-user point of view, does anyone have recommended configuration AOI machine to recomend for purchase?

what were the key benefits of this AOI to detect solder joint fillet issues that historical are not yet optimized to be filter out 100% by AOI?

Appreciate if only direct end-users of AOI folks harp, criticise & comment, and that the salesman types do not attempt to commercialize a technical/engineering discussion herein, thanks!

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A.O.I - no salesman pitch pls | 9 June, 2003


My guess is you're from China area, Four Tigers, or Korea.

I think you are limiting yourself by only asking for end users opinions, yet that is my long term disagreeably educated opinion.

I am going to one of these AOI things this week and maybe I will remember to give you some of the feedback results, SMTA-Boston, NEPCON-East, on this site..

I have never (30years) really liked AOI since it always seemed to be another way to have inspection replace process and the great human eye. Yet now days based on reduced human visibility capabilities and greater visual techniques with software it is getting close to a MUST HAVE.

I am still not a full proponent; although I understand the future capability, yet I could be currently convinced that it has it's place. My process thought is just before human intervention is the place for AOI. You do have to train the humans as to their increased value due to piles of things AOI can't catch. Humans (those workers) must understand a lot to know their value and to correct those machines.

One of the companies I worked for wanted AOI only cause it was JAZY, "the latest and greatest". I have always been into productivity so we had our conflicts.

YiEngr, MA/NY DDave

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A.O.I - no salesman pitch pls | 10 June, 2003

Hi! Thanks to you as the first replier!

I do admit it "narrows" the information channels feedback flow by keeping this thread reply limited to "non-commercial" engineering folks, but I already have lotsa war stories from the salesmen around this region, and everyone is saying how good their product is. What I was looking forward to is info on which unit configuration is "good" from a direct-end-user perspective.

We did have plenty of opportunity to hands on with all kinds of new fangled inspection equipments, and final conclusion is human naked-eye inspection rein supreme on the list. BUT human fatigue is one area that cannot be ignored, couple this with variable factors such as GR&R drifters, we try to standardize and ensure a repeatability process control system. Its achieved for the Printer, P&P, Reflow, so how about the inspection stages?

My current data shows eratic swings in the inspection defects filter out by various groups of inspectors. I need accurate defect rates/types data to target and deploy my LIMITED resources, else we'll be firefighting all over the countryside. We need calm rational approach to identified problem areas and solve those problems step-by-step in terms of costing priority .

True we could correlate and retrain those drifters BUT humans tend to need the leaderships to motive them back into position? How long can we keep this up? How often can the customer hear this same excuse/reason "our is a new operator/inspector"?

Gone are the days when components were 1206/0805's and naked eye checking was sufficient. We now face components 0201's and CSP's which scope-aid inspection is mandatory. All this is cramp into smaller PCB estate.

I am personally agreeable that human still is the final judgement decision master. Machine and equipment is to assist the human where their basic functional capability cannot reach optimal performance levels.

AOI serves to remove the human eye fatigue from 24hours running inspection of cramped components in shrinking PCB sizes, and this AOI must perform at repeatable rates which is now at 6-sigma ideal.

"Jazzy" is what happens when white elephants take over.

"Optimal Productivity" is what happens when logical application plans meets to kinetic action in motion.

Pray the machine does not over-ride the human way of life, believe that was what triggered the story behind the Matrix anime series?

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A.O.I - no salesman pitch pls | 10 June, 2003

Sorry guys. I'm not in agreement with your nightmarish vision of a Matrix based future. As a guy who has worked in the trenches since the 70's myself....I would say that anything that replaces humans in this business is a good thing. I've seen the evolution first hand from automatic through-hole equipment to 45,000 parts/hour chipshooters and every one of these machines had a tremendous impact on quality and output over human assembly. This goes for inspection as well as you have both stated. In my perfect world there wouldn't be anyone running these factories. Just automation and the maint. guy needed to keep them up. If you guys are paranoid over automation, perhaps another line of work would suit you bettor.

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A.O.I - no salesman pitch pls | 10 June, 2003

In a perfect world, the machines would be maint."guys" for the automation machines. Think "closed loop" system.

Anyway, getting back to our reality job, we are still game for automation to improve thru'put, quality, reduce problems. The focus here is Automated Optical Inspection (AOI) machine.

My major concern now is what configuration of AOI is okey to filter out "solder fillet defects" (ie. no solder, unsolder, tilted SMD, tombstone)? Feedback is appreciated from direct-end-users of respective AOI.

PS: Most AOI these days have no problem filter out missing, upside-down, wrong (+/-) orientation; hence the attention to "solder fillet defects" in this thread.

Thanks in advance to the kind feedback & opinions.

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A.O.I - no salesman pitch pls | 11 June, 2003

Solder fillet inspection is something that I would avoid like SARS, solder joints are like a snowflake no two are the same, henceforth unrepeatability. The only time I would look into this would be for uBGA or flipchip on an audit basis utilizing X-ray. Ideally I would use a pre and post reflow inspection system to kill any debate over the best inspection method. However if you can live with a 99.5% to 99.95% first pass yield then the pre reflow concept will work just fine, most lines only run 96-98% first pass yield with a complex assembly without AOI. Also, make sure you have 100% solder paste inspection, if you have enough solder paste in the right location you should have a good solder fillet if you have done your homework, since implementing this on all of our lines we haven't seen a field return for a bad solder joint in over two years!!!

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A.O.I - no salesman pitch pls | 16 July, 2003

OK, disclaimer; I'm a salesguy, but I was a process engineer for quite a lot longer than I've been in sales.

Your question is very vague, and may be difficult to answer. There are many ways to configure AOI to inspect solder, but as has been pointed out, it is inherently prone to false defects. It does work, but you will have more operator involvement than with component AOI.

The multiple cameras, different lighting, etc are all there for a single reason, to get a good image of the joint. The image processing software will be different from every manufacturer, and you've got to determine which one works best for you.

Some of the questions to ask are:

What kind of throughput do you need?

Are there particular defect types you want to see, maybe at the expense of others? In other words, a machine that is very good at looking at fillets may be worse than others at looking for comp. defects.

How much time do you have to program? Are you looking for production volume or proto volume?

there are many other questions that can help you make your decision. I would start with a short list of questions that you need answered, and then do a vendor qualification survey to see who best fits with your needs. Get an on-site demo, with your boards, and your data, instead of some canned BS demo at a lab somewhere.

See? I was able to type a whole bunch or words without a sales pitch! Not bad for a peddler, huh?

P.S. Some of us actually care about the tech side of what we sell, we're not all full of BS.

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A.O.I - no salesman pitch pls | 17 July, 2003

My AOI wish list would include features that: 1)Character recognition, 2) Correct Placement (including missing), 3) Solder joint inspection (solder present), 4) Shorts, 5)Polarity check, 6)Coplanarity, 7)gerber/or Cad compatible (no gold boards), 8)easy/ flexible programming.

But as with AOI these features dictate high $.

1 Question I have is besides human intervention what is the need for the AOI is it for quality making 100% sure the board coming out is complete and correct? is it for Process prove out... verifying the front end machines are doing there job ? is it written in the contract to AOI inspect? Ultimatly the questions and info here will lead you into the machine you will need...

Cal Communications Test Design, Inc.

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A.O.I - no salesman pitch pls | 17 July, 2003

Good job Marty!!!! I KNOW sale-types can solid contributions to this forum and this is just another case-in-point.

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