View Full Version : Constrain hand in position without ik?

04 April 2003, 11:05 PM
I have a character that isn't setup for IK in the arms, but I want him to grab something and hold onto it while his body moves (without having to counter animate his hands everytime the body moves(which is practically every frame right). Is there a way to constrain his hand to this object just for this scene(and be able to animate it possibly turning on and off)? Can I do this through constraints to a locator or something?? Thanks.

04 April 2003, 11:11 PM
I think it might be possible to do this without an IK but I can't think of any reason not to just add an IK for this one scene.. it would be easier than using contraints.

Is the character swinging from something?

04 April 2003, 11:31 PM
Hey gmask. No, he's not swinging from something. he's grabing a bar at the beginning of the shot, then releasing and 'possibly' pushing off it just before leaving the shot. Reason I don't want to add an ik if I don't have to is because the character is referenced. I MAY just do that though if it's a real pain in the butt, but I wondered if there was a way around it. (But if the work around is more of a pain then proly I'll just have to create an IK version and transfer animation. Thanks.

04 April 2003, 11:43 PM
Hmm.. well I don't see why you wouldn't just apply the IK tot he referenced character.. since it is only for this one shot.

Otherwise to contraint the arms to the wall being pushed off.. I'm thinking you need some expressions that basically function as an FK where they control the secondary motion of the arms to rotate them to the target point.

I was also thinking maybe an expression on the root node of the character that woul dsomehow offset based on how far from the wall the hands wander. And then an expression on the elbow that rotates the arm to match.

04 April 2003, 11:46 PM
I'll just have to create an IK version and transfer animation. Thanks. [/B]

Yes actually this is sounding possibly better than anything else..

Do the main animation and then duplicate the skeleton and set up a bunch of rotation contraints onto the original so that it reads the values off the duplicate arms with IK's.. Although if you were using Maya 5 then I guess you could have used the blend attribute on the FK. Usually you'd want to rig a characters arms for both IK and FK for this purpose.

04 April 2003, 11:57 PM
yeah, I totally agree. I just didn't have time to set it up that way. So I just made a simple rig. I'll just transfer animation then, and animate everything but that arm if I can, then tweak it later. argh- I was affraid of that and was curios if there was some kinda constraint work around. oh well, I'll just duplicate the setup for ik and have two models. Thanks gmask.

CGTalk Moderation
01 January 2006, 01:00 AM
This thread has been automatically closed as it remained inactive for 12 months. If you wish to continue the discussion, please create a new thread in the appropriate forum.