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# 1 11-05-2006 , 04:26 PM
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FBIK arm question

If I have a normal arm say:

leftforearm,leftforearmroll, leftarm,leftarmroll,lefthand....

and my shoulder needs to have two joints like so:

leftforearm,leftforearm2,leftforearmroll, leftarm,leftarmroll,lefthand....
(I need this for shoulder plate armor to move once the arm is lifted so high.)

How could I get the FBIK to use it correctly?

I know I'll need to set joint limiting to get the armor working right, but my FBIK gets confused.

user added image

As you can see the arm swings under the armor and when that arm hits the round armor the armor must then move with the arm. Hope I explained that well.

# 2 11-05-2006 , 05:41 PM
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It seems to me that using Set Driven Keys or maybe expressions could be what you need. That's a little complicated to explain but look into it...

You could try parenting the shoulder armor to the clavical then keyframe animating it's rotation to simulate the arm hitting it.

# 3 11-05-2006 , 06:06 PM
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ya Velusion, I bit over my head. Although I do need a good reference on fbik's. So for all books and tutorial I have ovoid fbik's totally. I need to learn this though, so if you have any suggestion I'm open to it.

you said"t seems to me that using Set Driven Keys or" Just to clarify. I'm not, I have tried but failed. For right now I'm just limiting the joints. Once that limit is reached it rotates the next joint. I end up creating 3 ik's for one arm. It’s a mess.

you lost me here "You could try parenting the shoulder armor to the clavical then keyframe animating it's rotation to simulate the arm hitting it." I know what you mean by parenting, but not second part.

Have you used biped fbik? (youneedthisman.com). is there ever a point in using mayas fbik. It seems so limited.

# 4 11-05-2006 , 08:29 PM
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I haven't used FBIK but, like most things, it has its purpose.

Looking at your skeleton and reading your explaination, I think you're using too many joints. I mean, why do you have one right in the middle of the upper arm?

# 5 15-05-2006 , 12:05 PM
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That’s strange? My post is gone. Ok Ill try again..


I have extra joints for roll's Biped FBIK does this. No sure why but it wis an arm and an arm_roll joint. I could kill the roll joints if it would help. Just did that since it was recommended. Also the shoulder has two joints. The leftarm2 is connected to the skin under the shoulder that you can’t see. It allows the x movement. z and y are locked. Leftarm is connected the the shoulder joint and allows the z movement and a bit of x and y.

# 6 18-05-2006 , 04:49 AM
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link

Heres a good link on quickly setting it up. Its very picky with joint positioning and naming too (after skinnning, you must put you joints in a T stance...and than apply the FBIK)....its exactly like the way you need to seup if you're exporting to Motionbuilder (cause thats where its originated from).

Anyways, heres the link, hope it helps:
https://www.3dkingdom.org/modules.php...rticle&sid=807

-Also...the maya help files are really good on how to animate with FBIK...pining and unpining etc....just do a search on full body IK


Last edited by varley; 18-05-2006 at 04:51 AM.
# 7 18-05-2006 , 11:07 AM
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this is the tutorial I used. And your right its good, but didnt answer my question about the extra joint I needed to get the armor working right. After I rig it the arms fold in and are not usable. no matter what I try I can get an ik or fbik to work correctly on my arms.

# 8 19-05-2006 , 04:05 AM
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from the maya documentation...only the joints listed there will allow this tool to work. You might have to use set driven keys or to achieve this.

Also, this tool is taken from motionbuilder, in which your skeleton wouldnt work with that extra bone....it does allow extra joints in certain places...but not where you are trying to add it.


Last edited by varley; 19-05-2006 at 04:07 AM.
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