Correcting the elbow orientation control

00:03

We would need the elbow control to stay where it is rather than move to the hand,

00:09

having it this close to the hand can cause the IK to flip.

00:13

So how do we keep it away from the hand? But also still make it follow the hand.

00:19

Well, we need to use something that will act as an offset.

00:23

So let's just create a locator

00:26

and let's rename it to armlet

00:28

IK swap position

00:29

or pause for short,

00:32

add the elbow control to the selection

00:35

and then go to modify match transformations, match all transforms

00:39

and move the locator to the control.

00:42

We're going to use this as a proxy for the arm I care control.

00:45

So the elbow control will blend to this instead.

00:49

So to make the locator follow the arm A K control, we simply parent it to it.

00:55

If I move the arm control, now the locator follows but maintains that offset.

01:00

What we need to do now is use a locator's position instead of the arm control.

01:06

So

01:06

take its world matrix zero attribute

01:09

and connect that to the blend matrix node instead.

01:13

So it goes into target matrix here

01:16

and that's set up Now,

01:18

all we need to do now is make the follow attribute control, the blending.

01:22

So take follow from the arm PV control or the elbow control as I've been calling it

01:28

and connect that to the blend matrix nodes envelope attribute.

01:33

So that's going to control this.

01:35

OK.

01:37

So the arm control is set to world

01:39

which means I can move the arm control

01:42

and the elbow control stays where it is.

01:45

If I change this to hand now

01:47

the control moves but to the locator. So it's maintaining the distance.

01:51

So we don't get any flipping issues with the IK.

01:55

This also means it will follow as the arm moves.

01:59

What makes this even better is the animator

02:01

could place the locator wherever they like,

02:04

they could even animate it for even more flexibility.

02:08

So that's a basic two way space swap.