FK foot not orienting properly

[irenepu]

Hi,

I’m having trouble orienting the fk foot controller so that it’s flat to the ground.

My character’s leg is more bent and turned outwards. After placing the guides and building the rig, the Ik foot ctrl is to the orientation of the ankle guide, but when I switch to fk, the fk controller’s direction is pointing down to the effector control. But it’s oriented on one axis, when I would expect it to be flat or have the same orientation as the ik foot controller.

FK Foot Orientation, seems like the controller is twisted on one axis when I would like it to be flat, and hte orientation where the Y axis is pointing upwards:

An example using the human biped template:

fkRotation.mb

Thank you

[Jerome]

Hello @irenepu and welcome to the forum.

In order to have the FK foot control aligned to your foot component you need to allign the leg_L0_eff and the leg_R0_eff to the same orientation your foot are having.
Just out of curiosity you changed your up axis on your Maya settings? When I opened your guide’s file the template was facing down (I mean like if the character was on the ground)

I haven’t test myself mGear while changing the UP axis so I am curios to know if this could lead to any problem.

Thanks

[irenepu]

Hi Jerome,

Ok! I’ll go try it out!
We’re working with Z-up. Yes, we did have some issues with the ik foot.
One thing I did have to change was in the foot_bk_01 shifter component: I changed the matrix position for tip_ctl from

v = datatypes.Vector(self.guide.apos[-5].x, self.guide.apos[-1].y, self.guide.apos[-5].z)

v = datatypes.Vector(self.guide.apos[-3].x, self.guide.apos[-5].y, self.guide.apos[-5].z)

Thank you.

[irenepu]

Hi Jerome,

I used an orient constraint with maintain offset turned off to align the leg_L0_eff to the leg_L0_ankle, and built the rig after that, but it’s still making the leg_L0_fk2_ctl with an angle and not flat to the ground.

Maybe I’m not orienting it correctly?

Thank you.

[Jerome]

@irenepu

The offset/translate X shift that you have guide leg_L0_knee is normal? Is your character asymmetrical?

JD

[irenepu]

@Jerome
Thank you for the heads up, I’ve gone back and adjusted the guides so that there’s no offset/translate X shift.

I’ve looked at the docs and videos, but I have some questions with guide placement for the legs.

I’ve tried a scene with one leg and I’m seeing some differences in the rotation of the ik ctrl based off on how I rotate the leg_C0_root.

Attached file legPointOutwards_v002.mb is the rectified guide of the leg. (Please open these files with the Z as up axis)
https://drive.google.com/open?id=1oNFG5Pt96R0GDCt0_5ze1_t-r0p_PcIY
In this file, the guides follow the direction of a relatively straight leg with a bend, where the character leg pose would be like a T pose with the feet closer together. When the rig is built, fk and ik controllers have the same orientation, which is awesome!

However, if we have a character that is standing in an A pose, I rotated the leg_C0_root, on the rotate Y to splay the leg outwards, and rotated the foot control to world space. When I build, neither the fk or the ik controller’s orientation is following the leg_C0_ankle guide’s orientation.

Attached file legPointOutwardsTilt.mb to show the difference in between fk, ik, and ankle guide(Please open these files with the Z as up axis):
https://drive.google.com/open?id=1ACRqXNBvKr28Jsz_8F8jQ3YNbSmR-1FL

Ik controller orientation shifted from value on the Rotate Y on the leg_C0_ikcns_ctl:

Fk controller orientation is different from the leg_C0_ankle guide’s orientation:

If I zero out the rotate Y on the leg_C0_ikcns_ctl, the ik controller follows the orientation of the ankle guide.

But I’m not quite sure how to place the guide so it doesn’t create this orientation difference upon building, and why the Fk and Ik controllers aren’t oriented in the same orientation as the guide?

Thank you.

[irenepu]

@Jerome

In the legPointOutwards_v002.mb(same link as above, please open with Maya set to Z-up) it seems the ik foot controller is built with the Y-axis pointing downwards instead of upwards, despite the fact that the ankle guide was positioned with Y-upwards.

Controller orientation, with Y pointing downwards:

Guide orientation, Y pointing upwards:

Maybe this is because of it being made in the Z-axis?

Is there a way in the guide to specify what axis the controllers upon being built will point to, without having to dive into the code?
For example, I’d like to change if from the controllers pointing upwards in Y to Z-axis, or for example, for the spine, I’d like to change the orientation direction so that the controllers point down the chain on the X-axis.

Thank you.