I just need something to work with the mechanical equipment it controls
Apparently you just don't need a run of the mill desktop linux distro, but some special purpose to control some hardware, right ? The good news is that all linux systems are more or less equivalent for that. The bad news is: what is you equipment ? Does it support Linux ? Do you need to write software for it or are you provided drivers ? If the latter you should ask your hardware provider what they recommend, not us.