Character Rigging Tutorial

Character Rigging can be categorized into 3 general sections. Skeleton Creation, Animation Control Setup, and Weight Painting. When you are done with these, you will test your rig before you give it to an animator.

Rules to Follow While Creating a Skeleton:

Good Naming Convention for all the Joints.
- Name your joints after there body part (arm, leg, spine, toe...)
- The name of the joint should indicate the side of the body (LFT, RGT, CEN)
- If there are multiple joints with this name, use a numbering system (01, 02, 03)
- EXAMPLE: spine_CEN_01, spine_CEN_02, arm_LFT_01
Organize and parent correctly! Name joints as you go, not at the end! Your outliner should be clean.
All the joints must have XYZ rotation of 0 in the Channel Box.
Try to use only the TranslateX channel to move joints and use the Joint Orient section to rotate them.
Joint Orientation needs to be setup logically. (They rotate in the same direction as real human joints.)
All forward motion should be going in the same direction. (We will not be enforcing this rule due to the lack of time. However, this means that if we were to select the whole skeleton, and rotate in the x direction, the model would all curl in the same direction)

Useful Tools and Tips:

When you first start making joints, you may realize that they are too small or too big. To change the size that the joints are displayed go to Display>>Animation>>Joint Size .
When we say that all forward motion should be going in the same direction, we mean that you should take into account the local rotaion axes of the joints (these are the x, y, and z coordinate systems that are shown on each joint in step two of the skeleton). To display the local joint axes, go to Display>>Transform Display>>Local Rotation Axes.
After you start rigging, DO NOT MODIFY THE GEOMETRY AT ALL! To keep yourself from selecting the mesh (which is also annoying when you are trying to select joints) click the "select surface objects" button (it is up at the top above the shelves and it looks like a blue wavy square divided into 4 smaller squares). This will make it so you cannot select anything with a surface (you will only be able to touch the joints and cons in this scene).
You may want to use the x-ray feature instead of looking at wireframes or just plane smooth shaded (x-ray is the semi-transparent version of the model that you will see in some of the images in this tutorial). To use x-ray mode, make sure that you have a check mark next to Shading>>Smooth Shade All. Then go to Shading>>X-Ray. The shading menu is the menu in the viewport, not at the top with the file menu.

Directions for Creating a Skeleton:

1:The whole skeleton can be created with the Maya Joint tool. Under the Animation Menu Group, click on Skeleton >> Joint Tool Options.
Default Joint Tool settings.

2: The Spine and Head: In the side view, create the Root Joint at the pelvis of the body and then the first Spine joint directly above it. Continue to create as many joints as necessary until you reach the end of the top of the head. If you need to readjust joints, ONLY USE TranslateX channel to move and the Joint Orient Attribute for rotation. This will ensure a clean skeleton without unncessary channel information. To get to the Joint Orient boxes, hit Control-A for the joint you want to modify. To ensure that you are doing this correctly, the Transform Attributes for Rotation should all say 0.0, as should the Translation for y and z. Be sure to name your joints!! This will be important later (Step 7).
Spine and head joints.		Joint Orient Toolbox.

3: The Leg: We will be building the left half of the skeleton first. The Knee is bent just a little so that the IK Handle control will know which way to bend (when we create the IK Handle later on). Make the skeleton for the leg starting in the side view. If you make the skeleton in this view, it will ensure that the entire skeleton for the leg is in the same plane (which also helps the IK Handle know which way to bend). Start from the hip and keep creating joints down to the toes. When you are done creating the leg skeleton in the side view, go to the front view and move the hip joint so that it is centered in the left leg. (Make sure you are following the joint naming convention as you go... the names are displayed in the images below).
Leg and feet joints.		Front View.


4:The Arm: From the top view create the skeleton for the arm starting with the Clavicle. Make sure the elbow is bent just a tad so that the IK handles will know which way to bend. (Although, you can manually set a Preferred Angle for the joint and it will do the same thing.) Here is where you should check that the joint axes are in the correct direction. Note that the positive y direction for the elbow is pointing forward whereas the positive y direction for the wrist is pointing downward. To change an axes that is pointing in the wrong direction, use the joint orient box in the attributes editor for the joint. When you have all of the axes pointing in the correct direction, you should angle the wrist downward just a touch so that the palm will be at the correct height to attach to the fingers. You can angle the wrist downward by clicking on the wrist joint and changing the joint orient. DO NOT use translate y on the palm to achieve this angle! Remember, you want to keep translation and rotation off of the joints themselves. The root of each joint chain should be the only joint that has translation other than x. Look at the front view image to see what the angled down wrist should look like.
Shoulder and arm joints.		Top View.

5:Hand. First go to the top view and create the middle finger joint chain (as straight as possible! You may use grid snapping - press x when you are placing each joint - and then adjust the length of the finger aftwerwards - by changing the x translation - to ensure that you will get a perfectly straight finger). Then duplicate the middle finger for the index, ring, and pinky fingers. You will have to rotate the fingers horizontally, make sure you are using the joint orient rotation in the Joints, and NOT the rotation under the Transform Attributes tab in the attribute editor. Now make the thumb in the top view. Make sure that you rotate it after you create the joint chain so that it matches the side view picture of the thumb skeleton (below). Make sure that the finger skeletons are in the correct placement in the side view (by creating the finger joints in the top view, they will show up on the top plane of the grid - which will be near the feet of the model). The positive y axis should be pointing downward for all of the fingers, but inward towards the hand for the thumb.
Joints for the hand.		Side View.	Outliner for the hand.

6:Parenting all the joints together. With all the joints created, now you have to piece them all together into one single skeleton. Click on the Clavicle joint, shift-click the Neck_1 joint, and then press the "p" key to parent the arms to the spine. The order in which you click on joints matter. The parent should always be selected last. Next click on the Hip joint, shift-click the root/pelvis joint, and press "p". Parent all of the fingers to the palm joint by first clicking on all of the children, (index_LFT_01, middle_LFT_01, ring_LFT_01, pinky_LFT_01, and thumb_LFT_01) and then the parent (palm_LFT_01) and then hitting "p" on the keyboard.
Clavicle parented to the spine joint.		Hips parented to the root joint.	Fingers and Thumb parented to the palm joint.

7:Mirroring Joints: Click on the Clavicle (collar) Joint and then go to the Skeleton >> Mirror Joint Option menu. It should be mirrored across the YZ, Behavior Function, and if you used my naming scheme (which you should have done throughout this process - if not, do it now), Search for: LFT and Replace with RGT. Do the same for the Leg chain by clicking on the hip.
Mirror Joints Options.
8:Binding Skin and Setting a Neutral Pose: Expand the Skeleton Hierachy in the Outliner and select all the joints except for the end joints (having a good naming scheme will make the end joints easy to spot). Then select the model and, in the Animation Menu Group, go to the Skin>>Bind Skin>>smooth bind options. Choose the options from the image below and then click bind. Now your rig will be a pretty rainbow color (hooray!) if not, something is wrong and you should ask a TA for help. Before going any further, set the neutral pose for the character by clicking on the top level Joint (Root/Pelvis) and select Skeleton>>Retargeting>>Set Neutral Pose. This will let you get back to the original pose of the character by selecting the root and then clicking Skeleton>>Retargeting>>Go To Neutral Pose. DO NOT DELETE HISTORY AFTER THIS POINT! Deleting your history will destroy the skin, so you may wish to save your work now (honestly, save your work right now).
Selecting all the Joints except for the ends.	Smooth Bind Options.

Now make some controls!