I’ve been working with Unreal Engine 4 lately, but I’ve been having problems with round-tripping models and animations from UE4 to Blender and back. Blender seems to add an additional root bone to my armature.
I found a modification to the ascii exporter to prevent it from doing this, but I need some of the features only available in the binary FBX export. Does anyone know how to prevent FBX export from adding a root bone when exporting Binary FBX files?
Thanks!
I’ve been having the same problem, but I found an article that has solved it all. Take a look at this article. It may be focusing on character rigs, but the FBX export section applies to all kinds of rigs; vehicle rigs, etc. Here’s the link: http://krisredbeard.wordpress.com/tutorials/tutorial-blender-to-udk-player-model/
P.S it might be a little out of date and the python script might be arranged differently, so I do HIGHLY recommend that you do backup the scripts you’ll be modifying according to the article.
I appreciate the help. Unfortunately, I’ve seen this, but he’s editing the ascii version of the exporter, not the binary one 
. The binary version is more recent and has some features I currently use, but the export script is a LOT more complicated than the ASCII exporter, and I haven’t been able to figure out how to eliminate the root node in it.
I already tested converting a vehicle rigged FBX file and importing it into UDK (yep, I’m using UDK) in the *binary format. And it works perfectly fine. I’m have a good feeling that it will work fine on UE4 although I never used UE4 before.
**As a matter of fact, I already modified my script in Blender, so I’ll give you a copy of it to make things easier for you. Here you go: https://www.mediafire.com/?330uttwzjtx399t
P.S This script is used in Blender 2.70
The destination folder is here: C:\Program Files\Blender Foundation\Blender\2.70\scripts\addons\io_scene_fbx
Remember to backup before you put the script in the folder!
Just managed to find a way, it is really stupid but quick and easy to pull off.
Rename your extra bone to ‘‘Armature’’ Unreal by default dissolves this one. the problem is your animation loses the scale… So…
Go to Pose mode on your Armature and scale up your Actual root to 100
that should solve everything.