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snot_nose
11-14-2002, 05:16 PM
with the swivel we rotate the whole arms, but in the real world when we rotate our arms, the forearm is rotating more then the upper arm, isn't it? if they both would have the same rotation then the shoulder part would get a twist isn't it?

jschleifer
11-15-2002, 12:40 AM
by swivel, what do you mean exactly? holding your arm out straight and twisting it so your hand goes from palm up to palm down or something like that?

snot_nose
11-15-2002, 11:17 AM
yep, i ment the swivel wich is part of the ik setup in max

jschleifer
11-15-2002, 06:28 PM
ah, I don't use max, so I'm not sure exactly how the swivel works there.. you're having trouble with the skinning of the arm?

snot_nose
11-16-2002, 01:56 PM
Yes, i got the shoulder twist, and also my faces got inside each other when the arm was bent in the joint elbow.
so i thought maybe the problem was with the bones setup and not the skinning.

Transform Gizmo
11-23-2002, 07:20 AM
yeah, swivel angle alone i have found doesnt do the trick by itself to get realistic rotation of an arm. the reason for this is the way it works, by rotating the entire IK chain on the axis created between the start joint and end effector (end effector axis) theres a much more indepth description of swivel angles in the max ref.

snot_nose
11-24-2002, 06:06 PM
did you find how to fix this problem?

Transform Gizmo
11-26-2002, 06:18 AM
---with the swivel we rotate the whole arms, but in the real world when we rotate our arms, the forearm is rotating more then the upper arm, isn't it? if they both would have the same rotation then the shoulder part would get a twist isn't it?---
my expertise with character rigging doesnt go extremely deep, but as far as getting a more realistic rotation, getting the forearm to rotate more than the rest of the arm, i remember an article in which i saw a picture of a rig, and the arm had more than one bone in the forearm area. so i played with a rig the other night, and what i tried, was creating two smaller bones that spanned the length of the forearm. linked the two bones to the forearm, and then wired their rotation to the swivel angle of the ik chain. then i adjusted the expression for each bone so that the farther down the arm the bones were, the more they rotated. as i said i dont have a whole lot of experiance in this area. so ill attach a picture, and hopefully im understanding what the problem is.

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