Next we will set a new attribute to drive the heel-toe rotation. Select the RF_Root and add a new attribute called heel_Roll with the following parameters: float, min –5 max 10, default 0. Using the Set Driven Key Window, load the RF_Root, RF_ToeMid, and RF_Ball into the driven section and select the rotateX attribute. Load the RF_Root into the driver section and select the roll attribute.

Set Driven Key window

Set a key with all the attributes and rotations set to 0. Set the roll attribute on the RevFoot_Root to –5 and set the rotateX to –30. Select the three items listed in the driven section and with the rotateX selected hit Key. Set the roll attribute to 5 and zero out the rotateX on the RevFoot_Roll. Change the rotateX on the RF_ToeMid to 20 and RF_Ball to 20. Again, set a key for all three items in the driven column. Set the roll attribute on the RevFoot_Root to 10. Set the rotateX on the on the RF_ToeMid to 40 and the RF_Ball to 30 and then set a key for all three joints. You should have keys set for all three joints at the –5, 0, 5, and 10 values for the roll attribute. Select all three joints (RevFoot_Roll, RF_ToeMid, and RF_Ball) and open the graph editor. Select the three curves and change the tangents to flat. This will give you a smooth transition from the heel to the ball to the toe.

roll attribute at –5

roll attribute at 5

roll attribute at 10

To get the outside and inside toes to rotate with the middle one we need to add to the reverse foot assembly. Select the two last joints on the inside and outside toes. Duplicate these joints and unparent them from the joint chain. Parent them to the RF_ToeEnd joint on the reverse foot assembly.

added to the reverse foot

Hide the reverse foot. Make and IK Handle that spans from the Toe01 to the T0e03 for each of the inside and outside tow joint chains. Unhide the reverse foot and point constrain the IK Handles to their respective toe joints on the reverse foot. Now the toes should follow the middle toe during the fool roll action. You can hide the IK Handles on the toes at this point because you will never have to touch them again unless you need to set up pole vectors.

IK Handles for toes

This set up seems to work OK for me. I could also scale the RF_Toe joint to get the feet to spread out or in. I could tie this in to the roll attribute so that when his toes are off the ground, they come together and when they are taking the chickens weight the spread apart. Let me know if you have any questions or suggestions. My email is spudk@texas.net.

Editor's Note: Check out Kapp's The Rabbit of the Apocalypse on iFilm.com