Iron will not walk in the conventional way, instead his walk will be more similar to that of a wind-up toy (see figure 1 & 2). Some features of the usual foot rig for a cartoon character will not be useful for Iron, such as Toe Tap or Heel Lift (see figure 3), Iron's feet are to be solid objects that will not undergo deformation. I have also researched into what Iron's blink might look like (see figure 4).
|Fig. 1: Sadness wind-up toy walking (front) [source]|
|Fig. 2: Sadness wind-up toy walking (side) [source]|
|Fig. 3: Heel lift [source]|
|Fig. 4: Sonic blinking (edited) [source]|
Because Iron does not have a neck, I have improvised his head's movements in the context of the alcove. Below is my demonstration of Iron's head rotations, using locators in place of the joints, and a spare head. This demonstration has also enabled me to figure out the max rotation values to which I can push the head before it hits the torso/alcove.
Using the very basic method of cutting a copy of Iron's head into two pieces, I have figured out the precise position for Iron's jaw rotation joint. In actual practice, the geometry will not be cut up, and will instead use a fall-off to reduce the movement of the 'chin''s point as much as possible, to keep the facial deformation to the front half of the head only; if this skinning method does not work out, I will try another method.