How to Create a Skeleton in Maya Part 1

Difficulty: Moderately Challenging

Instructions

Things You'll Need:

Autodesk Maya
Patience and time.

Step 1

Maya Joint Tool

Start out by selecting the Joint Tool (Skeleton > Joint Tool) and click on the origin and the click down to the knee, but come out one grid unit from the Y-axis origin. See picture below:
Step 2

Maya Bones

Now continue and click down further but along the origin as before this joint will be the Ankle joint. Click once more slightly further down and over away from the origin, then click once along the same axis as the last joint but further away from the origin. See pictures below:
Step 3

Maya Attribute Editor

Now be sure to name all the joints. Use “Left” or “LT” to denote which side of the body it is on. (example: Left Upper Leg)

Next we need to set limits for all the joints. This way they will only rotate as much as we want them to and it makes for easier fine-tuning in the Graph Editor. To do this we need to select each joint and open the Attribute editor to set the limits. Look for the sub heading “Limit Information” and click the Arrow button just to the left of the heading. Now you should see something like below:
Step 4

Limits are basically minimum and maximum rotation controls. With this set you cannot rotate outside of these settings. Try the settings below to get you started, but you may find that they will need to be customized to the character mesh.
For X, then Y, then Z of the Upper Leg joint:

Minimum Default Maximum
-20 0 20
-45 0 75
-75 0 75

Next try these settings for the Lower Leg joint:

-10 0 10
-15 0 15
-18 0 95
Step 5

These for the Ankle:

-10 0 10
-10 0 10
-50 0 30

And these for the Ball joint:

-10 0 10
-5 0 5
-15 0 30
Step 6

The toe joint does not receive any Limits, as it is not rotated. Now on to the IK chains:

Click on the IK Handle Tool (Skeleton > IK Handle Tool …options box). Always reset your IK tool before you use it. This will set it to the Rotate Plane solver. Now click once on the Hip joint then next on the Ankle joint. Name this IK handle “Left Ankle IK”. Press the “Y” key and bring back your last tool used and Click from the Ankle to the Ball joint. Name this one “Left Ball IK”. Press “Y” again and click from the Ball to the Toe joint and name this one “Toe IK”.
Step 7

Maya Outliner

Select the Toe IK and group it to itself and name it “Toe Bend”. Hit the insert Key and hold down the “V” key and drag the Pivot point down and snap it to the Ball joint. Next Select the Ball IK and the Ankle IK chains and group them together. Name this “Ball Pivot” and move the Pivot point to the Ball joint using the “V” key again to snap in place.

As a side note it may be wise to do this in the Perspective view to make sure the Pivot Point snaps into the correct spot. When you are done simply hit the Insert key again to switch back to the normal Transformation tool set.
Step 8

Maya Attribute Editor Render Stats

Now Select the Ball Pivot and the Toe Bend groups and group them together and name it “Toe Pivot”. Move the Pivot Point to the Toe joint with the Insert / V keys again.

And finally select the Toe Pivot group if you don’t already have it selected and group it to itself and name it “Heel Pivot”. Move the Pivot Point for this group the Ankle joint.

Now lastly create a polygon cube and move it to the Left ankle. Name it “Left Foot Ctrl”. Scale it to fit around the Ankle and Toe joints. Then open the Attribute Editor and open the Render Stats menu. Turn off all the check boxes like below:
Step 9

Maya Attribute Editor Drawing Overrides

Now open the Object Display Menu and the Drawing Overrides menu and Enable Overrides and turn off Shading and Texturing.
This will prevent the cube from being rendered out and shaded in the view port.

Parent the Heel Pivot Group to the cube by selecting the Heel Pivot first then the Cube and pressing the “P” key. Now move the Pivot point of the Cube to the Ankle joint.
Step 10

Maya Set Driven Key

The rigging is now complete, but in order to take advantage of the rig we need to lay down some Set Driven Keys.

To do this we first need to create an Attribute on the Foot Ctrl object (Cube) with the following info:

Name: Foot Roll

Minimum: -1

Maximum: 1

Default to: 0
Step 11

Now open the Set Driven Key Window by Selecting the Animate menu then Set Driven Key.

Select the Foot ctrl object and Load it as the Driver, next Select the Heel Pivot, Toe Pivot, Ball Pivot and Toe Bend groups and load them as Driven objects like.
Step 12

Okay now select the Roll Attribute from the Ctrl Object, then Select the four Groups from inside the Set Driven key window. Now select Rotate X and press the Key button.
Since this is the middle of a cycle we will use it as our default position. Now Select the Attribute from the object and change the value to –1. Switch back to your Heel Pivot and retard your X rotation by –50, then the Toe Bend Rotate X to –20. Click the Key button
Step 13

Select the Foot Ctrl object again and set the Roll attribute to 1. Next set the Rotate X values for Heel Pivot and Toe Bend back to 0. Now set the Rotate X value of Toe Pivot to 60 and hit the Key button.

One more key to go, set the Foot Roll Attribute to .5 and set the Toe Pivot Rotate X to 0. Finally set the Ball Pivot Group to 40. Press the Key button on last time.

Now everything is tied to the Roll attribute which you can now use in your walk cycle.