Fitting a Biovision Skeleton to a Character Studio Skeleton (CS to BVH) in Motion Builder Tutorial

By Jimmy Almeida and Kevin Wang

This tutorial picks up where the CleaningCS_SkinnedWeightedModels left off.

1. Obtain the cs_bvh.fbx file. 

2. Open the Cleaned Character file of the model that you need to work from and append it to the scene.

3. In the Properties Pane, Change the color of the cs_bvh skeleton by clicking and dragging in the RGB boxes.

4. Pick the root of the Character that should be called Reference.  In the Transforms Pane, notate what the scale values read.

5. In the Perspective view, press Ctrl+A.  This toggles x-ray mode and allows you to see through the character to the skeleton.  Also, press Ctrl+2 to give yourself two windows.  Click in one and press Ctrl+W to bring in the Schematic View.

6. Pick the root of the CS_BVH.  In the Transforms Pane, enter those same values for it scale.  It is ok if it is bigger or smaller than the character.

7. Now we need to align the joints to the characters joints.  CS_BVH’s only have 2 spine joints.  If you have more than two spines, you may have to split the difference between two of them.  This particular case has two spine joints and will match up with the cs_bvh. 

8. Start with the Pelvis or Hip joint of the CS_BVH.  Alt+drag it to the hip of the Character.  You will know you have picked the characters joint because it will light up green.  Let go of the mouse button and a dialogue box will pop up.  Go to Align>Translation>All.  The CS_BVH’s Hip snaps to the characters hip.  Do the same for all the Spine, Head, Neck and Legs (up to the ankle).  Don’t do the Clavicle, Arms or the End Effecter for the foot.