Keywords: Maya, Rigging, Joint Chain, Skeleton

Maya Rigging series of articles:

Joints Notes

How to create root joint

Rigging (F3) -> Skeleton -> Create Joints -> Left click anywhere in viewport.

If you left click in viewport multiple times after click Skeleton -> Create Joints, joints would be connected automatically as a joints chain.
If you want to create multiple joint independently (not connected), you should end the current joints chain by hit Enter.

How to end current joints chain, two ways:

  • Hit Enter (Recommended).
  • Right click in viewport to quit Create Joints mode, the first right-click would create a last joint.

Tip: You can hit G to switch to the last tool that has been used (e.g. Create Joints) when you finish a joint chain and want to create a new joint chain.

How to create child joint

Menu: Skeleton -> Create Joints, then select target joint (e.g. Joint A) which want to create child under it in Outliner Panel, then click in Viewport to create Joint B, thus Joint B was the child of Joint A.

How to attach joint to mesh surface automatically

Hold down the key V while creating joints.

Make sure Camera Based Selection is on, otherwise joint will may attach to the back surface.

How to centering joint in mesh

By default, joints will snap on ground (Z = 0) when creating new joint.

Solution:
Skeleton -> Create Joints options -> Check Projected Centering

Result:

How to rename joint using keyboard (no mouse)

Press key Up and Down to select joint, then hit Enter.

Make sure cursor is inside Outliner, otherwise press Enter doesn’t work.

If want to jump cursor between joints at the same hierarchy, press Left or Right.

How to locate to selected joint in Outliner

Select the target joint, then hover the cursor over the Outliner and hit F.

Or right click Reveal Selected:

How to rename joint name in a batch

Modify -> Search and Rename Names:

How to connect joints

Select source joint (as Child, must be the root joint) firstly, then select target joint (as Parent), Skeleton -> Connect Joint.

Reference: Connecting Maya Joints in a Min

How to connent parent joints (connect joints with a new joint)

Press key P: Select child joint first, then select parent joint and hit P.

Unparent: Shift + P

How to mirror joints (create symmetrical skeleton)

Skeleton -> Mirror Joints:

How to tweak joint pivot (joint transfrom)

Press key D to toggle pivot tweaking state after the joint has been selected.

How to dump joints (copy and past)

Shift + D:

How to show joints overlayed the mesh

Toggle X-Ray joints.

How to switch pivot space (local space or world space)

1st way (Hotbox): Hold W then hold down the LMB and drag.

2nd way: Tool Settgins -> Axis Orientation -> Object.

Q: How to open Tool Settings panel?
A: Click the Tool Settings icon on the top-right,

or double click the tool icon you want to use.

How to display Local Rotation Axes

Show Local Rotation Axes on selected joint:
Display -> Transform Display -> Local Rotation Axes

How to align Local Rotation Axes to joint orientation (Orient Joint)

When you move joints multiple times, the Local Rotation Axes may misalign from the joint’s orientation.
Solution: Skeleton -> Orient Joint.

Toggle the visibility of Local Rotation Axes while orienting joint.

If there’s warning when orienting joint:
Warning: skipping joint03,it has non-zero rotations.
That means you had rotated the joint before, you should clean the joint’s rotation before orienting joint.

How to Assume Preferred Angle

Right click the target joint, Set Preferred Angle first, then you can Assume Preferred Angle.

How to change hierarchy of child joint

As shown in following image, Joint BBB is a child of ROOT, and BBB has no child joints:

If want to change hierarchy of BBB as a child of AAA, do setps follows:

  1. Create a child joint under BBB:
  2. First select BBB, then select ROOT, Skeleton -> Disconnect Joint:
  3. Now BBB would be a new root joint:
  4. First select BBB, then select CCC, Skeleton -> Connect Joint:
  5. Then BBB would be a child of AAA which is the parent of CCC:

There’s no way to change hierarchy of BBB without disconnecting BBB firstly, otherwise you would get a error:
// Error: file: D:/Autodesk/Maya2020/scripts/others/doDisconnectJoint.mel line 32: Cannot disconnect the end joint.

How to delete joint

Note:

  • You can only remove one joint at a time.
  • You can not remove a root joint.
  • You can remove joints from the skeleton of a character with a bound skin without having to detach its skin.

To remove a joint

  1. Select the joint that you want to remove.
  2. In the Rigging menu set (press F3), select Skeleton > Remove Joint.

Reference:
Remove joints - Autodesk Maya Documents

Issues

Cannot connect sibling joints

Case:
There’re some error messages while connecting joints.

Error: Cannot connect sibling joints.

Or:

Error: line 0: The child joint must be a root joint.

Caused by:
Maybe it’s a bug of Maya.

Solution:
Restart Maya, or reimport asset(e.g. FBX) in a new scene, or create a new child joint in parent joints, then connect target joints and source joints again.

Unable to find the bind pose for : / test_group / root_joint. Use the DAG node current transform.

Error log on exporting control rig as FBX:

Unable to find the bind pose for :  / test_group / root_joint. Use the DAG node current transform.

Solution:

To nuke all of the bindposes:

  1. In outliner go to Display and uncheck DAG Objects Only
  2. Then in the search bar look for bind that should show every bindpose in the scene, delete them all.
  3. Clear the search bar, and turn on DAG Objects Only again.

Rebuild the bindpose:
Then select every joint in your skeleton and execute command dagPose -bp -save (In the MEL bar, bottom lower left corner type command hit enter).

https://polycount.com/discussion/209134/maya-unable-to-find-the-bind-pose-when-exporting-to-fbx

Tutorials

Youtube Tutorials

Intro to Rigging in Maya 2019
https://www.youtube.com/watch?v=1wvdQy2Fdhw

Autodesk Maya 2018 - Simple Character Rigging Part 1 of 3
https://www.youtube.com/watch?v=cOokoFED7QE

Rigging in Maya | Fundamentals - antCGi
Rigging in Maya | Basics - antCGi
Rigging in Maya | Intermediate - antCGi
Rigging In Maya | Advanced - antCGi

Realtime Creature Rigging Workshop (2 / 19) : Joint Fundamentals
https://www.youtube.com/watch?v=z4yclj31vXg

Realtime Creature Rigging Workshop (Recommended)
https://www.youtube.com/playlist?list=PL8hZ6hQCGHMUIOilrww1u-mo0sTwYs2W5

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