Retargeting Mocap data in Motion Builder

In this article you will learn how to retarget FBX or BVH exported files from Axis Studio to Motionbuilder

Software Setup

Axis Studio Export Settings

File Type: .bvh or .fbx

Skeleton: Maya/MOBU/Human IK

Enable: Displacement

Axis Neuron / Axis Neuron Pro Export Settings

File Type: Select FBX binary

Characterize Mocap Data

Open Motionbuilder and drag in your BVH or FBX

Highlight the skeleton and make sure the timeline is on the first frame. Go to the Properties tab and set all the Rotation values to 0 so that the skeleton is in a perfect T pose

In the Asset Browser, go to Templates --> Characters. Drag the Character asset onto the hips of the character in the Viewport.

Click Characterize --> Biped

If this option does not pop up, delete the character in the outliner and try again

CharacterizeMocapData.png

Next, go to the Outliner and rename the character to MOCAP. This is just for organization purposes.Save as a new file.

RenameToMocap.png

Characterize Character Model

  • Open a new scene and drag in your character's FBX file
  • Highlight the skeleton and make sure the timeline is on the first frame
  • Go to the Properties tab and set all the Rotation values to 0 so that the skeleton is in a perfect T pose
  • If you cannot see your character model’s skeleton, press Ctrl + A

In the Asset Browser:

  • Go to Templates --> Characters
  • Drag the Character asset onto the hips of the character in the Viewport

Click Characterize --> Biped. If this option does not pop up, delete the character in the Outliner and try again. Then go to your Outliner and rename the character.

CharacterizeMichelle.png

BipedMichelle.png

Remember to save.  I would recommend naming the file CharacterNameCharacterized

Retarget Mocap Data to Character Model

Open a new scene and drag in your characterized motion capture data. Drag in the characterized character model. Click FBX Merge --> All Takes

Next, go to the Outliner and click on the character’s name. Check Active, Change Input Type to Character and Input Source to Mocap. The motion capture data should now drive the target skeleton.

CharcterAndSource.png

Next, click on Plot Character --> Plot to Skeleton. The animation data is now baked to the character model’s skeleton, and you can delete the mocap data skeleton from Characters and Scenes in the Outliner

Save as a new file.

Getting Ready to Edit

Now just a few more steps before your character is ready for editing in Motion Builder

  • First, click on the character in your Navigator
  • Click on Plot and this time select Control Rig --> FK/IK
  • You can now click on the points on the control rig or on the character controls window to modify your character’s position

Next, go to Animation Layers and add a New Animation Layer. You will primarily want to use this new layer for your animation cleanup.

You now have a character ready for animation cleanup.