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Maria-Avramova
01-03-2005, 09:59 AM
Hi everyone,

I am trying to set-up a character for a short movie. I am having problems with IK/FK set-up on arms. My prefered set-up is that I still can use the rotation of the joints of the arm while animating the acting but than turn on an Ik or a separate wrist that I can use when the character places its hands somewhere.
All the tutorials Iīve read are binding the IK wrist but the palm is still rotating and has to be keyd afterwards.
Could you please give my some advice or recommend some books/videos/tutorials that I can buy/see.

Thank you in advance.

M.

poly-phobic
01-03-2005, 01:38 PM
Hi everyone,

I am trying to set-up a character for a short movie. I am having problems with IK/FK set-up on arms. My prefered set-up is that I still can use the rotation of the joints of the arm while animating the acting but than turn on an Ik or a separate wrist that I can use when the character places its hands somewhere.
All the tutorials Iīve read are binding the IK wrist but the palm is still rotating and has to be keyd afterwards.
Could you please give my some advice or recommend some books/videos/tutorials that I can buy/see.

Thank you in advance.

M.im not sure what u are trying to aske here, but i think that is how its suppose to work, for the wrist to follow the arm, and u have to explicitely key the wrists rotations when u need to.

there are other set ups that allow that to be different of course, u can have the wrist rotated with the arm as to be orienting itself when the arm moves and still be able to explicitely control its rotations.

btu rephrase your question, i'm not sure i understood qutie rigth.

poly-phobic
01-03-2005, 01:38 PM
**edit double Post**

Me109
01-04-2005, 05:07 AM
best setup is to create a hand helper / ctrl .. Group the controller ( centre the pivots )
orient constraint (with offset) the helper object to the wrist bone..
then orient constraint the elbow bone to the 'group' of the of the helper object..

this allows the hand to track the orientation of the elbow joint.. and also allows secondary rotation on the wrist without annoying snapping...

with grabbing object however you want the wrist to maintain a fixed orientation.. I find that by switching the evelope of the elbow to helper Group orient constraint from 1 to 0 makes this work without to many problems... to clean up the rig you can create a attribute on the wrist helper object and connect it directly to the constraint...

anyhow... hope this helps....

Maria-Avramova
01-04-2005, 07:34 AM
Me109, thank you. I think that is going to help. Just wondering, are you using the group constraints on the wrist while the arm has an IK?

Me109
01-04-2005, 11:56 PM
Hi ya... yeah no group constraints.. just use CTRL - G command to group the object.. I've attached a generic arm setup that I use... very simple... open up the outliner to see how I've arranged it all... has IK hidden... and under the wrist helper ( sphere ) are addition attributes for finger control and switching between fix and floating wrist setups.. I tend to avoid FK and you'll notice that IK works very well in this example... anyhow cheers

opps.. can't attach.... heres a link

http://student.ci.qut.edu.au/~n4675215/misc/handRig.mb (http://student.ci.qut.edu.au/%7En4675215/misc/handRig.mb)

cheers

CoolDuck
01-06-2005, 11:27 PM
best setup is to create a hand helper / ctrl .. Group the controller ( centre the pivots )
orient constraint (with offset) the helper object to the wrist bone..
then orient constraint the elbow bone to the 'group' of the of the helper object..

this allows the hand to track the orientation of the elbow joint.. and also allows secondary rotation on the wrist without annoying snapping...

Wow thanks a lot for this, I was looking for a solution like this. I wanted a built in FK wrist control in my IK rig, this works perfect. I needed the hint of the elbow to ctrl constraint.

Maria-Avramova
01-12-2005, 07:56 AM
Hi ya... yeah no group constraints.. just use CTRL - G command to group the object.. I've attached a generic arm setup that I use... very simple... open up the outliner to see how I've arranged it all... has IK hidden... and under the wrist helper ( sphere ) are addition attributes for finger control and switching between fix and floating wrist setups.. I tend to avoid FK and you'll notice that IK works very well in this example... anyhow cheers

opps.. can't attach.... heres a link

http://student.ci.qut.edu.au/~n4675215/misc/handRig.mb (http://student.ci.qut.edu.au/%7En4675215/misc/handRig.mb)

cheers


Thanks a lot Me109. I tryed this set-up and it worked perfectly. Thatīs the simpliest IK/FK set-up Iīve seen and works great.
I didnīt make that arm you sent me to work. But I see the set-up.

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