Constraining rotation along one LOCAL Axis

I have a robot, and one joint on his limbs should only be able to rotate on one axis, like a piston, or like a knee joint…hes made of mesh bits parented together, cause i was too slack to bone him. it works fine if the robot is in his starting pose, i can just rotate in the side vew…but obviously as soon as i have limbs in different places, i cant rotate along only one local axis…i tried using constraints but they dont work…i read in another post something about DoF or depth of freedom, whats that about?

please help! :frowning:

It’s only available (and only possible) in the CVS builds or Alpha builds, whatever you want to call them. Here’s a link to the TestBuild forum so you can see all the builds available:

Aaagh… it’s down! Anyhow, one of the builds there is an Alpha build of 2.40 (official BF build) which will suit your needs.

If you can’t wait for the Blender site you can get a build here:


ok…thanks…how soon do you reckon b4 these alphas will become stable? have u used them > are they very unstable right now?

Maybe 2 weeks, yes and no.


cool thanks for your help…