http://www.isobudgets.com/shop/product-category/calculators/
Good subject. I haven't used the one you linked to but the price makes it look like it's tailored for students.
I use the full version of ISG Uncertainty analyzer for formal estimates and the RSS method when someone asks in a general way about the uncertainty of a measurement.
ISG offers a freeware version of some of their software so you can get an idea what it's like before you buy. Here's a link http://www.isgmax.com/freeware.asp
Developing an uncertainty budget is a boatload of work. It doesn't make sense to me to do all of the work more often than is necessary so I believe that whatever software or method is used the database should be capable of being updated when the standards are recalibrated or the calibration interval has changed etc.. so that only the uncertainty contributions that have changed need to be addressed.
We had an auditor suggest Quametec a few years ago but I'm not familiar with their software.
We use uncertainty ToolBox from Quametec. No problems
ISG is very NOT user friendly and difficult to work with. Most auditors don't like that because they don't understand how it works. Uncertainty Toolbox from Quametec is the auditor preferred software. I've used both for about 5 years each and I prefer the Uncertainty Toolbox because it is based on Excell.
I agree, ISG is very "opinionated" about how it is used. What I read about Uncertainty Toolbox "showing your work" makes a lot of sense and so does using a common spreadsheet to save data.
Quote from: RFCAL on 09-28-2016 -- 10:17:16
We use uncertainty ToolBox from Quametec. No problems
UncToolbox not good for many measurements results (when calibrate near 30 - 40 points) because toolbox generate sheat in one excel document.
We have not seen that problem. You just add another sheet
I don't think excel can do partial derivatives, but maybe it has some sort or Monte Carlo functionality? Or do these spreadsheets expect you to determine the combined uncertainty equations before entering the data? If so, that's a ripoff... once you have the equations the rest is easy-peasy plug-n-chug.
ISG (Integrated Sciences Group) founder and president Dr. Howard Castrup is arguably one of the most knowledgeable individuals in metrology (and has been recognized as such numerous times by NCSLi, NASA, etc.) when it comes to measurement uncertainty, statistical process control, and other metrologically related mathematics. I trust his integrity and products implicitly, though I have not used the Quametec product.
Quote from: measure on 10-05-2016 -- 09:25:23
ISG (Integrated Sciences Group) founder and president Dr. Howard Castrup is arguably one of the most knowledgeable individuals in metrology (and has been recognized as such numerous times by NCSLi, NASA, etc.) when it comes to measurement uncertainty, statistical process control, and other metrologically related mathematics. I trust his integrity and products implicitly, though I have not used the Quametec product.
So you're making a judgment call based on not making an actual comparison?
I trust George Washington, a founder of this country, and overseer of the Constitutional process but that doesn't mean I would trust every law that came afterwards based on who the founder was...
Just sayin...
I won't argue the integrity of the Castrup's. They are leaders in this field. However, their software is NOT user friendly. We were using it at one time, but A2LA forced us to switch to an excel based software in 2013. That's when we went to Quametec.
Most calibration lab need to know the uncertainty of their measurement. Most of those calculations are relatively easy because the manufacture's published spec's have much of the work done behind the specification they give you.
But not all uncertainty calculations are created equal. Tools like what the Castrups provide can do the simpler calculations, and most importantly the complex one's used to calculate partial derivatives, distributions, standard deviations and risk.
Most of this complex uncertainty analysis is what is behind a specification published in a manual (from a reputable company).
It really comes down to what level of uncertainty calculations do you really need for the work that you are doing. What happens if you are a little wrong? What happens if you are wrong a little more than you expected you would be wrong?
Mike
"The more I know about measurement uncertainty, the larger it gets." - Mentioned in one of the NCSLI sessions
I would like to change the quote from "The more I know about measurement uncertainty, the larger it gets." to "The more I know about measurement uncertainty, the larger it gets, and the more uncertain I become!" :)