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---Tutorials:

We will start with the legs as they can be the toughest part and make the most trouble for you if you get them wrong. I am going to assume that you answered "yes" to the question about having the feet lock to the ground or not. This is the most common way to rig a character. About the only time that I might not want to have the feet locking to a ground plane is if the character only swims or flies.

Scale of the character and the scene is something that should be taken into consideration when working in any package. I have often heard from people working in Max that it isn't as much of a problem when working in Maya. Maya rounds to more decimal places I believe so this is true. However, you still get allot of errors in any package if things get to small or large. I have seen many problems in both packages when it comes to scale that affect

Tripple IK Leg w/ Five Controls

This is one of the infinit possible ways that you can rig a characters leg and foot so don't think that it is the only way. I call this the Tripple IK Leg as we will be using 3 IK solvers linked to a series of control objects. I have hundreds of characters in production that are rigged this way and it works very well.

Create the bones:

 

  1. Start by creating a three bone chain for the leg as I have in the image [Fig 1.0]. The extra bone on the top of the chain is so the IK solvers swivel angle stays alined if we need to link or unlink the leg from the rest of the rig. I don't count the nub bone on the end as a bone but don't delete it as it is needed for positioning the bones as well as adding IK solvers. In Maya there is a round bone pivot that is added to the end of bone chains for the same reason.
  2. Next create a two bone chain for the foot and align, pivot to pivot, the root bone of the foot to the nub bone of the leg [Fig 1.1]. I create the bones in the foot as a seperate chain and then link them together to make is easier to unlike them once I have IK solvers added to the leg.
  3. Link the root bone of the foot to the nub bone on the leg.

Create IK Solvers:
  1. Create an IK HI Solver (or in Maya an RP Solver) from Bone02 to the nub bone at the bottom of the leg chain (Bone04).
  2. Create an IK HI solver from the root bone of the foot (Bone05) to the next bone in chain (Bone06). This is called a one bone solver as it solves the rotation of one bone.
  3. Create an IK HI solver from Bone06 to the nub bone at the end of the foot (Bone07). [Fig 1.2] show the end result.

Create & Link Control Objects:

You can use any type of control object that you want. I always use shape objects because they can be filter for durring animation. You can also make the controls any shape that you want so you can have cool looking controls. You can also use Dummy objects and point helpers for the same thing, but they are borring.

  1. Create a large control and align it to the ankle joint.
  2. Create a smaller control and align it to the ball joint.
  3. Place a third up above the toe bone.
  4. Place a forth in front of the foot on the ground plane.
  5. Place a fifth behind the heel on the ground plane [Fig 1.3].
  6. Select control #3 and using the hierarchy pannel and affect pivot only align the pivot to the ball of the foot [Fig 1.4].
  7. Link the controls in the order of the red arrows in [Fig 1.5].
    -Link control #2 to control #4.
    -Link control #3 to control #4.
    -Link control #4 to control #5.
    -Link control #5 to control #1.
  8. Now link the IK solvers to the controls by following the red arrows in [Fig 1.6].
    -Link IK Chain01 to control #2.
    -Link IK Chain02 to control #4.
    -Link IK Chain03 to control #3.
  9. Select IK Chain02 and in the motion panel change the Parent Space from Start Joint to IK Goal. This will make the twist rotation of this IK solver rotate with the main control object.

We need one more control for the orientation of the knee.
  1. Create a control object and place it in front of the knee [Fig 1.7].
  2. Link the knee control to Bone01.
  3. Select IK Chain01 and in the motion panel press the Pick Target button in the IK Solver Plane group and select the knee control object.

Usage:
Control #1 will be for moving and rotating the entire foot rig.
Control #2 will be for rolling the heel off the ground while the body moves for walk like in a walk.
Control #3 will be for wiggling the toes up and down.
Control #4 is for rolling the whole foot up on the toes.
Control #5 is for rolling the whole foot up onto the heel for when the foot is being placed back on the ground in a walk.
The knee control is to be moved side to side to place the knees orientation the way that you need.

Down load the final foot rig here.

trippleIKleg.zip

All the controls have been locked in the final file for the axes that are not needed. Bone01 has been left unlocked as well just so you can see how it works.