After the character mapping process, linking your character model to a Character asset, you can characterize the model to activate it in MotionBuilder and make it ready for animation.
Complete the character mapping process, manually or automatically. See Character mapping.
In the Navigator window > Character Settings > Character Definition pane, activate the Characterize option.
Character Definition pane A. Characterize option
Activating the Characterize option updates and lock the character definition in the Character Controls window > Definition tab.
A dialog box appears to remind you that your model must be in a stance facing the positive Z-axis. Choose between two types of postures for your character (Biped or Quadruped).
Once it is characterized, your character is ready to be attached to a motion source.
You can also use the options in the Character Controls window > Definition tab to characterize the character model. See Define a skeleton for HIK for more information.
If you want to characterize a 3ds Max Biped, see Characterizing a 3ds Max biped.