Home Technical Talk

IK/FK Switch, Joints Flip and Pole Vector not working

polycounter lvl 6
Offline / Send Message
visoutre polycounter lvl 6
I'm using the 3D Motive Bipedal rigging tutorial. I did a rough skinning pass on the left side of the model, but when I switched from FK to IK on the leg, the foot joint twists. Posing the IK leg deforms the model badly and the knee doesn't follow the pole vector like it should. I followed the tutorial step by step and when I set up IK/FK for the leg, I duplicated the femur joint chain 3 times, (normal, fk then ik) so joint orients should be okay since it's the same for all 3 versions. I'm not sure why it gets messed up when I switch to IK? The arms were set up in the same way and they work fine.

I even tried redoing the IK leg from the beginning of the videos and still have the same problem. Hopefully I won't have to mess around with the FK and normal joints because they're working fine... I'm just a beginner at rigging, so I have no idea how to troubleshoot this. I made a gif demonstrating the problem, but if that isn't enough I uploaded my Maya 2014 file: https://docs.google.com/file/d/0B3SraVScb5DLT0N0S1kzRkJBVVk/edit?usp=sharing


Untitled-2_zpsa89371f1.gif~original

Replies

  • antweiler
    Options
    Offline / Send Message
    antweiler polycounter lvl 8
    have you checked the settings of the orient constraint, that constrains the Leg to the IK and FK Leg? THe interpolation type should be set to "shortest"
  • visoutre
    Options
    Offline / Send Message
    visoutre polycounter lvl 6
    Thanks! I had it set to Average, but setting to shortest solved the foot flipping issue in the gif image!

    But there's still a problem when I pose the leg in IK, like in this screenshot FK is fine, but IK does all sorts of twisting and messes up the mesh. It shouldn't be a skinning issue because I have only skinned the normal joints and not the FK/IK.

    I'm thinking it's either the pole vector or the ik handles. The knee joint doesn't follow the pole vector like it should (image#2). I tested pole vector on a quick joint test and it reacted differently than mine. The IK handles could be causing the joints to rotate 180 degrees. It just acts crazy.

    issue1_zps69fefbf0.jpg%7Eoriginal

    issue2_zpse547df17.jpg~original
  • LeighKimmer
    Options
    Offline / Send Message
    LeighKimmer polycounter lvl 3
    Hey Visoutre,

    The same thing is happening to my ik joint chain as well - the joints flip 180 degrees when I add the pole-constraint and I am wondering if you know a way around this problem!:poly127:


    L
Sign In or Register to comment.