Which gauge R&R to use per AIAG

[Jayfaas]

Are there specific studies that should be used per AIAG that you are aware of based on the measurement system? To provide a little context, we have many gauges at my job in the automotive sector that range from big automated bench gauges down to wheels and indicators and even down to handhelds like calipers and dial indicators.

What I want to know is if there is somewhere the spells out a requirement for what type of MSA study needs to be performed. I would imagine automated gauges wouldnt require a 3x3x10 Gauge R&R since you are essentially taking out the operator variability. If thats the case, are there specs that define what they consider fully automated?

We have some gauges that load parts themselves, others load parts manually by engaging them on the headstock and moving the tailstock in using a joystick, then pressing the start button and its automated from there.

Our default is 3x3x10 but that is very time consuming and I am starting to think that it doesnt have to be a requirement for some of our gauging.

 

[Miner]

AIAG provides very limited guidance when it comes to special cases. Here is a little more specific guidance based on what I think you are looking for. If I missed something, just ask a more specific question.

• Manual measurement devices with replicable measurements will use the standard (crossed) R&R study.
• Manual measurement devices with non-replicable measurements (destructive) will use a standard (nested) R&R study.
• Automated measurement systems with self-loading will use a Type 1 R study.
• Automated measurement systems with manual loading require judgment. If the manual loading CANNOT impact the measurement, use a Type 1 R study. If manual load CAN impact the measurement, use a standard R&R study.
• Automated measurement systems with multiple test stations can either use a standard R&R study replacing the operator with the test stations or use an expanded R&R study if operator influence exists.
• If you have more than one automated measurement system of the same type, you can use a standard R&R study replacing the operator with the multiple systems or use an expanded R&R study if operator influence exists.

As you can see, there are a lot of potential scenarios. Hopefully, this gives you sufficient guidance.

 

[Jayfaas]

The automated systems we have with manual loading I would argue are not influenced by the operator as the fixturing has a headstock (static) and moving tailstock operated by a servo on a worm gear. It has a prox switch that stops the travel. So any variation would either come from the part or the machine. We have 2 like this and they are pretty time consuming when having to run 90 pcs which is why I was wondering.

We have a 3rd gauge where you set down a 2 pc shaft that sets the same way by having to put a bored hole over a raised button but then when you press the opti touch buttons, some festo cylinders straighten it out and then it measures. This one is exceptionally long because each measurement takes atleast 1 minute cycle time but its all automated. The only operator influence I can think of is if the operator loaded it with the wrong part of the joint facing up, but then you would get a completely different measurement. To make matters worse, its a measurement of torque on a joint which is using a load cell measuring force to determine the torque. Also the tolerance is 0.3-0.7N, and the shaft that moves weighs about 6-8 lbs.

That R&R is a nightmare which is another reason I was hoping that I could narrow that one down and maybe do a 1 pc 25 times or something. It also requires ANOVA method.

this topic was something I have been a part of since my new job but have always wondered if we were doing it right. The 3x3x10 is a pretty telling study but Ive often wondered if we may be doing too much with some of the machines.