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jasonwestmas
11-02-2004, 06:51 PM
Hi There,

I'm trying to get an arm to bend using IK. I have a hand bone, forearm, bicep and shoulder bone. I set the shoulder bone to unaffected by IK and it has keyfames set to all three HPB channels. The Bicep is set to IK in the Heading channel. The forearm is also set to IK in Heading channel. The hand bone is set to Fulltime IK, with a strength of 1.0 and has a rightarm null goal as a goal object which is at the wrist. Keep goal within reach is selected for the hand bone and has keyframes set to all three channels. According to my knowledge, the arm IK should now be complete. When I move the hand bone the bone doesn't push the forearm back as a chain IK reaction, instead it moves past the bone while the forearm stays in place. Do I need another goal or something? Has anyone ever had this problem?

Thanks

jasonwestmas
11-02-2004, 08:01 PM
Duhhh! In this kind of set up, one must move the goal object not the hand bone in order to move the entire chain. Never did it that way before. :rolleyes:

SplineGod
11-03-2004, 12:14 AM
Moving the goal is how its typically done or something that goal object is parented to. I usually use a higher goal strength. It sounds like the way you have it setup that youre arm is only going to be able to bend but not rotate to the side from the shoulder. Try setting whatever channel on your shoulder will rotate the arm out to the side to IK. Make the collar bone unaffected by IK.