how select a servo motor ?
That's going to depend on the actions you need it to perform and the environments it will be exposed to.
Otherwise, a helpful tip is to use the resources that the motor supply companies provide. They are well versed in the language and will be able to provide tremendous help if you have some of your specs already calculated out.
In pro-E you want to assemble with allowing motions
(User defind to pin or cylinder asseble options that connections make assemly to rotation)
In solidworks and inventer it named as mateing conditions
Catia not reqiurd any changes
*you didn't mentioned software name
In nxt question try to give software name with version