Two identical IK handle with different behaviours

[david.bellver]

Hello, recently i've been doing a rig on the Unreal Mannequin for Maya and i was almost done when i noticed this 

as you can see, the right leg ik handles displaces the foot joint when "stressed" enough whereas the left one doesnt. Both IK handles have the same attributes, is there any way that the right leg IK handle doesnt displace the foot joint?

[jmreinhart]

Are you able to post your scene?

[david.bellver]

@jmreinhart Here it is, there are some heel and toestip controls but i have disabled their visibility since i havent made them work properly yet but this shouldnt affect to the problem since it occurs only in one of the legs.

[jmreinhart · Accepted solution]

Is there a reason the heirarchy is set up the way it is? Typically you wouldn't have transforms in the joint heirarchy and especially not when using IK. And there's nonzero transforms on the groups joints too.

It is weird that the left and right behave differently, and I couldn't see why aside from the ikHandle not liking the transforms. If you remove them it works fine.

[Kahylan · Accepted solution]

Hi!

As @jmreinhart already said, having transforms in a joint chain that you use IK on is rather unusual and tends to cause problems. I'm guessing that you put them in there because you had odd transformations/rotations on your joints, maybe cleanly reorienting them would be wise to avoid problems down the line.

Also I would add a IK SC solver to between your foot joint and your ball joint, so the ball doesn't stick to the ground when you lift up the hip.

I hope it helps!

[david.bellver]

@jmreinhart Im not a master of rigging so this procedure may have been an error, having said that:

The reason why i did it is because the original model had the bones with transformations already skinned to the geometry and i wanted them to be frozen in order to set up the FK controls faster by parenting freezing unparenting and setting them up to zero but it would give me some problems. I ended up duplicating the rig, unbinding the skin, orienting the joints and freezing transformations both with the freeze transform button and by creating a group on each in order to save the transformations that coulndt be frozen, and copying the skin weights from the original mesh into the duplicated one.

Thanks for the awnser it works now.

[david.bellver]

@Kahylan Thanks for the awnser, the reason because it gets stucked to the ground was because the constrain from the ball control was parent, i have changed it to an orient constrain and it works.
Thanks for this method anyway, i may try that if i do another rig.