IK Constraints
Moderators: jesterKing, stiv
IK Constraints
could somebody explain the functions of these things? I don't know about IK contraints, and they sound pretty useful...
-
Guest
FK = Forward Kinematics
IK= Inverse Kinematics
The idea is that with forward kinematics you rotate and
parent objects to get poses you want..
With IK you create a end effector chain that determines
the rotations necessary to orient objects into a pose.
Your typical human body contains 70+ joints not including your
vertebrase in your neck and the others that allow you to move..
Without IK if you have to move each joint it would take you
forever, with IK, you only need to move fingers, wrists, feet,
and maybe a few extra end effectors to control knees and elbows,
the neck.. But its so much easier than what you would have to do.
Its questionable if its become easier in Blender, I read the
docs on OOM, and realized the artist avoided using character animation, which is a major weak spot of blender.. IT needs work..
IK= Inverse Kinematics
The idea is that with forward kinematics you rotate and
parent objects to get poses you want..
With IK you create a end effector chain that determines
the rotations necessary to orient objects into a pose.
Your typical human body contains 70+ joints not including your
vertebrase in your neck and the others that allow you to move..
Without IK if you have to move each joint it would take you
forever, with IK, you only need to move fingers, wrists, feet,
and maybe a few extra end effectors to control knees and elbows,
the neck.. But its so much easier than what you would have to do.
Its questionable if its become easier in Blender, I read the
docs on OOM, and realized the artist avoided using character animation, which is a major weak spot of blender.. IT needs work..
how it works
ok
- make three bones and orient them like a leg plus foot. make sure the knee is not completely stretched (angle less then 180 deg).
- press TAB to leave EDIT mode.
- create an Empty and remember its exact Object name (like "Empty" or "Empty.001"). move it to the joint where the foot starts (ankle).
- select your armature(bones)
- press CTRL + TAB (pose mode). now you can't edit length of the bones by moving around the joints, but rather move and rotate thebones themselves. anyway leave everything as it is ( as with "real" bones).
- rightclick the foot bone to select it and then goto CONSTRAINT buttons (the one with the chain symbol)
- Click ADD and choose "IK Solver". In the OBJECT field type in the name of your Empty. Click CTRL + TAB again to leave EDIT mode.
-Voila - you can move around the Empty and the bones rotate automatically.
hope that helps
- make three bones and orient them like a leg plus foot. make sure the knee is not completely stretched (angle less then 180 deg).
- press TAB to leave EDIT mode.
- create an Empty and remember its exact Object name (like "Empty" or "Empty.001"). move it to the joint where the foot starts (ankle).
- select your armature(bones)
- press CTRL + TAB (pose mode). now you can't edit length of the bones by moving around the joints, but rather move and rotate thebones themselves. anyway leave everything as it is ( as with "real" bones).
- rightclick the foot bone to select it and then goto CONSTRAINT buttons (the one with the chain symbol)
- Click ADD and choose "IK Solver". In the OBJECT field type in the name of your Empty. Click CTRL + TAB again to leave EDIT mode.
-Voila - you can move around the Empty and the bones rotate automatically.
hope that helps
-
luckybreak
- Posts: 11
- Joined: Fri Nov 22, 2002 12:35 am
