leg rig : flipped?!

[flumo]

Hi there,
I'm kinda new into rigging, a specially in XSI and have experienced an "error" already.
It's nothing advanced, simple stuff but would not like to start rigging this thing again.

At some point, while testing custom parameters my character's leg flipped and I can't get back to previous state. What's up? Any tips on how to fix that?

Here is the screenshot... just in case.
http://www.flumo.org/xsibummer/rigFlipped.jpg

Best of all,
F.

[3dtutorial]

Dunno -- I'd check the placement of your up-vector constraint perhaps.

Joe

[flumo]

that's the thing... cube that's close to the knee is not used actually. it's simple chain, no addons.

but... i've managed to do something different. you gave me the idea. ive added upvector, the leg got fixed... then deleted it. everything is back no normal! thanks for inspiration ;)

[3dtutorial]

Excellent, glad that was of some help!

Cheers,

Joe

[scaron]

well you probably need an upvector... so removing it again isn't going to stay fixed.

you also need to look into the kinematic chain/joint properties read all the details of those parameters. there are certain settings that help the ik solve in the right direction. choose the best for your character.

but please add your upvector back or sooner or later you will run into the same issue.

[flumo]

thanks for your help!
but could you give me any tips on how to add upvector in a smart way? so i dont have to move it all the time while animating?

F.

[scaron]

parent it underneath a part of your rig so it stays relative to its overall position

one thing i like to do is put a control at the root of the leg, align it with the top joint, put the upvector as a child of that new control. then use this control as a 'swivel' to rotate the knee position. make sure the new swivel control is a child of the hips or pelvis. so now instead of translating the upvector you are rotating the upvector around the ik legs local axis

[flumo]

thanks a lot! you've made my day :) now im off to more advanced rigging!