@Yeti TUGenius already posted a link to a video of the Stonehearth Add-On. The easiest way will be using that one (it supports export of skeleton-files / rigs and animations).
Here you can find a thread related to the Add-On in the discourse-forum:
And here is the homepage with a manual:
http://www.stonehearth.de/weblog/blender
Just let me know if you get stucked.