Uncertainty Calculation for Roundness - Talyrond 73 roundness instrument

[HALDUN]

Hello everybody
At first i would like to thank you all for this great forum.

We have Talyrond 73 roundness instrument in our lab. and I have to calculate measurement uncertainty for roundness until next Wednesday.
My problem is that, i couldn't arrange the uncertainty budget because i have no idea about which parameters affect the result.
All the helps are welcome.

Haldun

[Hershal]

First, begin with your Type A. This is the readings that you take. Get standard deviation, divide that by square root of n, where: n=the number of readings you take.

Next, take the uncertainty of your machine's clibration. This is a Type B and is normal distribution.

Then environmentl issues, these are Type B and are rectangular, so divide by square root 3.

There may be other issues also, but this will get you statred.

Hershal

[HALDUN]

Thank you so much for your help Hershal.

[sermet]

I saw an example of roundness uncertainty budget in the following NIST pubblication: emtoolbox.nist.gov/Publications/NISTJResNov-Dec97-102-6.pdf .
I hope it helps you.

Sermet