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sebrady
12-06-2011, 12:24 PM
This is my 1st attempt to make an IK chain in LW10........nothing I do works. I make 4 bones parented to a null, each bone parented to the previous. I parent a null to bone 4 and make bones IK 1-4 IK in rotation. If I push the goal null, NOTHING happens, only the null moves.

IK is on, deform is on. Any ideas.

evenflcw
12-06-2011, 12:50 PM
The goal null shouldn't be parented into the IK chain! Hows that gonna work? You will get cyclic dependencies - Move goal null, affects bones via IK, which affect goal null via parent-child relation and so on. No good. Unparent or parent the goal null to the root of the hierarchy instead, ie to the null the bones are parented to. To make the goal null a goal null you have to set it as goal item on bone 4.

It would be easier to tell exactly where you you might have gone wrong and how to correct it if you posted your scene file.

RebelHill
12-06-2011, 01:10 PM
what he said...

also...

Do be aware that multibone IK in lw can have be difficult to control, and usually requires a certain amount of know how to make it behave properly and as intended. If starting out you should go with simple 2 bone stuff, as for arms or legs, and get to know the IK from there. If you want more infos on doing longer chain IK, theres a vid in my free RHR pack that covers the options available, and ideas for controls and management.

RebelHill
12-06-2011, 01:11 PM
what he said...

also...

Do be aware that multibone IK in lw can have be difficult to control, and usually requires a certain amount of know how to make it behave properly and as intended. If starting out you should go with simple 2 bone stuff, as for arms or legs, and get to know the IK from there. If you want more infos on doing longer chain IK, theres a vid in my free RHR pack that covers the options available, and ideas for controls and management.

RebelHill
12-06-2011, 01:11 PM
gah...

sebrady
12-07-2011, 05:20 AM
nothing I do works, IK is on. Inverse Kinematics is on for Heading and Pitch. Bone 3 has Null2 for goal.



http://dl.dropbox.com/u/2159257/Screen%20shot%202011-12-07%20at%207.03.26%20AM.png

RebelHill
12-07-2011, 06:40 AM
yes... but your goal (null2) is the CHILD(!!) of the chain its meant to be controlling.

Unparent it.

sebrady
12-07-2011, 10:53 AM
Duuh......thank you Mr Rebel

UnCommonGrafx
12-08-2011, 05:03 AM
Post 2 was the answer.

dlanimation
12-11-2011, 06:10 AM
hi
In lw7.5 content /scenes/features/inverskenematiks are a couple of ik set ups..
very helpful. heres one if you cant find.
good luck
dl