If you intend to have standing as professional mechanical engineer, be sure the accreditation is accepted. Many, if not most, online degrees aren't recognized, no matter what they tell you. Easiest way to find out is to see if credits can be transferred/accepted to a state university.
If you just need the education for specific applications you probably can find that information here or in tech support info on line. Motor manufacturers, ball screw suppliers, all have tech sections in their online catalogs.
Machinery's Handbook is full of info. College/University book stores can supply a lot of the reference material you might need as well as libraries.