Any Maya joint can be converted to a capsule. This is useful since you do not need to create a separate capsule object that would be parented to a joint. Instead, the joint itself can get the Muscle Object shape and be directly connected to the Muscle skin deformer.

To convert joints to capsules

1. Create or load some joints in the Maya scene.

   While it is not required, you want to align your joint axis such that one of the local axes points cleanly down the length of the joint chain. The default for Maya is X. You can use any free joint orient tool to align your joints that way, or before creating joints, you can use the Joint Tool settings and set the Orientation to yzx and the Second axis world orientation to +y.

   Regardless, you need to know which axis you are using for the axis down the length of the joint.

   

2. Select the joint(s) you want to convert to capsules.
3. Select Muscle > Muscles/Bones > Convert Surface to Muscle/Bone from the main menu bar.
4. In the window that appears, select the axis you are using down the length of your joints.

   

   The objects are converted to have capsule shapes. You can now colorize and change other settings for the capsules. Their default length and radius is set based on the initial joint locations.

   

   NoteDue to a Maya limitation, Muscle Object parameters for converted joints can only be set using the Channel Box and Muscle Parameters tab. Using the Attribute Editor only works if you manually select the Muscle Object shape node directly first.