I do not currently know of any completely free software that would do what you want. I also do not know of any shareware (pay after you try it) software, although a few companies do have time-limited trial versions.
Assuming you have a computer system with general-purpose office software installed (Microsoft Office or equivalent) you can already do much of what you listed.
- Calibration database: you can create a calibration record database using a relational database system such as Access. Remember that each tool must be undividually identified, and that each one may have many transactions of the same type. Or, a filing cabinet with a folder for each tool works, as well.
- Calibration scheduling: this can be a reporting function of the database. Or, you could keep a separate file in a spreadsheet.
- Document calibration procedures: a word-processor program can be used for this, and then Adobe Acrobat (separately purchased) to save them as digitally signed tamperproof copies.
- Calculate uncertainties: you can use a spreadsheet program for this, if you are comfortable with the math. Or, this is the one function that does have an excellent free program. The current version of Uncertainty Calculator is available from a link on this page: https://metrologyforum.tm.agilent.com/download.shtml
Again, you may already have what you need to create your own system. A disadvantage of doing it that way is that it may be difficult to manage the interactions, and to control the use.
An advantage of a complete system is that everything usually works together. Another is that many of the commercial package developers are aware of ISO/IEC 17025 and are improving their products to meet new requirements. The biggest disadvantage, of course, is cost.
Automating calibration procedures is very specific to your installation. What you need depends on what your computer system is, some specific hardware in the computers, and the interface capabilities of your measurement standards. You will need to purchase specialized software - there are many that could be used.
Another consideration is that you must validate all software used to produce calibration results. Validation means that you must prove that the software you use produces correct results. This would specifically include data collection and storage, data reduction and analysis (including uncertainty), and the automation system.
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If you do find a free software package that really does all of this, please let me know as well!
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