View Full Version : ik chain vibration

01-20-2006, 12:12 PM
Simple question.

I have a simple ik chain with 6 or 7 bones in linear position with a null at the end (goal). Simple simple....

when the chain is a very bended is ok and the bone follows the null but when I move the null for having the extended chain (as in position 0) the chain it vibrates and it loses the contact with the null?

The goal strenght is 1000 and with 10 and 100000000 is the same.

With the option Keep Goal Within Reach the problem is that I can move the null where I want... is not a solution

You can download the zip file with the video http://www.vass3Design.it/problem2.zip

This is the video http://www.vass3Design.it/problem2.avi


01-21-2006, 10:41 PM
I couldnt view the avi files for some reason. Try posting the scene file

01-22-2006, 01:57 AM
I just made the same setup and mine does the same if the null us lower than the IK bone in the distance of the bone chain.
I don't think what you are trying to show can be done.

Without bones rotating (which is what yours are doing), you can't make bones bend back thru themselves and go the opposite direction without getting bone popping like that.

But there could be something I'm missing.

I even locked all rotation channels for all bones, tightened stiffness, and still couldn't get bones to change bend directions 180 without bone popping while they are in bent position. I always have to make the chain straight with null away from the IK bone abit before I could bend them and not get the popping.

01-22-2006, 03:35 AM
I would use IKBoost to do a chain like that. Much easier to control with less hassle.
You could also try setting up multiple goals along your chain.