Divided parameter wiring (rotation) makes a suddenly jump - Help

Ok, this is my setup:

One ExposeTm(helper) "reading" from an object - three objects where i want a fallof in the rotation (for twisting the forarm). Hope this creat the picture.

I am wiring x to x rotation (all set to zero from the start), and then dividing.
Something like this:

Local_Euler_x / 2

At some point in the rotation the three wired objects suddenly jumps in the rotation.

Please help me.



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PIXandDOTS's picture

Thank you, might be close...

MKlejnowski: This could be what i am looking for (converting the Euler to Quat angles).
The problem now is that orient constraint use xyz, but i only need to transfer the x rotation (see the attached file).

The arm rig is a "hose-like" arm, with fk and ik.

barigazy: Thanks for the link, i am new to scripting, but would really like to get to know more, and at some point to use it in my produktion flow. If you have any noob tutorials you can recomend please do so.

Again thanks for your time.

armrig.jpg 320.39 KB
barigazy's picture


this site by Paul Neal can be useful http://paulneale.com/tutorials.htm


MKlejnowski's picture

Twist Bones..?

I never seem to have had good luck getting twist bones to work without screwing up when using Euler. You could try using Quat angles and a rotation script. Here is an example for the setting up a twist bone for the wrist which I use.

1. Create two point and set their position and rotation the the HandJoint.
2. Now parent or link the first point to the handJoint. We will call this the refTwist
3. Now parent the second point to the lowerArmJoint and we call this the newTwist
4. Now change the newTwist rotation controller to a ScriptController and open it up so you can edit it.
5. Now create two variable called parRot and refRot (you will see a create variables on the top left)
6. Now assign node the HandJoint to parRot and refTwist to refRot
7. Add this to your expression

oldRot = refRot.transform.rotation * (inverse parRot.transform.rotation)
(normalize (Quat oldRot.x 0 0 oldRot.w))

8. Once you evaluate you should have twist bone which will turn at 100% based on the hand. From there you could add extra joints and use an orientation contstraint using the original lowerArmJoint and the newTwist . Also you could adjust the twist bones by rotate the refTwist by its x axis.

Not sure if I made it clear. Let me know how it works out.

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