Setting up the foot IK control

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Let's look at setting up the IK foot now and

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this is a little bit more complicated.

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Let's hide the FK joints and bring back the IK ones.

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What we're going to do with this version of the

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foot rig is add in a simple foot roll control.

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This will take the foot's pose from being back on its heel,

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up onto the ball of the foot

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and then over onto the toes.

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So the animator only needs to adjust one attribute to achieve all three posess

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quickly and easily. This is ideal when working on walk or run cycles,

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we will also add in the ability for the foot to bank from side to side too.

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So to create the foot roll, we simply need a joint chain

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which will drive the main foot.

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This is known as a reverse foot.

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Let's start by duplicating the main foot joint

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as that's in the ankle position. Already

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delete the Children.

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I'm going to rotate this. So it's more in line with the toes

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which will make the movement more predictable and exact.

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OK, let's move it out of the hierarchy.

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So it's just sat inside the leg group.

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We want this joint to be on the floor. So set translate Y to zero,

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which will bring it back down

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and move this back.

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This will be where the heel will pivot from.

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So here looks good,

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but we can adjust it later if needed once things are up

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and running and we can see how the foot is rotating.

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Let's rename this 2 ft left, reverse heel

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and delete that constraint note too.

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Duplicate this and move it forward.

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This will be where the foot pivots when the creature is standing on its toes.

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So put it between the end of the claw

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and change its name from heel to toe

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and parent it to the heel joint,

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duplicate the toe joint and move it back

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this time. It needs to be in line with the first tour joints here.

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So as the foot rolls forward, it bends on the toes,

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call this one bald,

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create another copy and parent it to the ball joint.

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Call this ankle.

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We want this one to be back where the ankle joint is,

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although we need to keep it aligned with the rest of the reverse foot.

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Ok. Let's match the ankle's position first.

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Just the position, not the rotation.

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I'm going to use a reroute tool now,

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which will essentially flip the joint's hierarchy.

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So the ankle joint is now at the top.

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This will allow me to adjust the rest of the foot joints to align them with the ankle.

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Switch to the top view for a second

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and isolate the joints.

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And now we can adjust the rotation to line them up.

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It's important these are all aligned or the foot won't roll correctly.

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OK. That's better.

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We can swap the hierarchy back now using the reroute tool. Again,

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we need the hierarchy this way around. So the joints rotate in a specific order.

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So the heel moves the whole foot like this,

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the tour then lifts the ball and the ankle

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and the ball moves the ankle.

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So you can start to see how we are going to get the foot to roll.