How to create robustness checklist from p diagram

[Robbie53024]

I disagree, sorry. The engineer defines the tolerance, therefore this is under control. The variation comes maybe from the process or over time in use. But not in a design P-Diagram. In my understanding this is not logically.

Your understanding of "control" and "variability" in this context are incorrect. The engineer may specify the tolerance, but the fact that the dimension varies from the nominal (ideal) value causes the system to experience variation in response. Imagine a steel I-beam that has nominal dimensions and tolerances on each of those dimensions. The i-beam that is on the larger side of those dimensions is going to be stronger than one at the lower (smaller) side of those tolerances. Of course there are many factors that go into this, including chemistry, temp, defects, etc. But everything else held constant, the dimensional differences is going to result in differences in performance. This is the variability that is being described.

 

[Jimmy123]

Your understanding of "control" and "variability" in this context are incorrect. The engineer may specify the tolerance, but the fact that the dimension varies from the nominal (ideal) value causes the system to experience variation in response. Imagine a steel I-beam that has nominal dimensions and tolerances on each of those dimensions. The i-beam that is on the larger side of those dimensions is going to be stronger than one at the lower (smaller) side of those tolerances. Of course there are many factors that go into this, including chemistry, temp, defects, etc. But everything else held constant, the dimensional differences is going to result in differences in performance. This is the variability that is being described.

What I said, it comes from production or wear over time or temperature, etc, if the product is in use, but not the definition on the drawing is a noise. Read this paper, it explained it very well: https://www.nist.gov/system/files/documents/2017/05/09/robdesgn-1.pdf

 

[Jimmy123]

Attached is an example of a completed matrix and P-diagram from the Ford FMEA manual. This is the best I can do. If you are a Ford supplier you can access this here.

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Your link for download doesn’t work anymore. Do you know a second source for the robustness xlsx ? THANK’s.

 

[Miner]

Your link for download doesn’t work anymore. Do you know a second source for the robustness xlsx ? THANK’s.

You will find the new handbook here.