Question on Joint Movement (DoF Question)

The relevant section of the Blender manual Wiki is currently empty of content, so I ask my question here. I can find no information about how to create different shapes (ranges) of Degrees-of-Freedom (DoF) for joints. I have a humanoid character and that should have human-like limits.

Using the right shoulder as an example, the theoretical DoF should be a sphere around the right shoulder joint. Given the theoretical DoF of a sphere, the volume wherein the upper arm would intersect the body should be subtracted to produce the actual DoF of the right shoulder. This would give a DoF-sphere with a large “hole” in one side. This seems impossible with the current DoF controls (sliders).

What is the problem? I am looking to find more information about defining the DoF for a joint. Perhaps the DoF-shape I’ve talked about is impossible at this point with Blender. Some practical examples would be priceless as, like they say, a picture is worth a thousand words.

Thanks, Bob

The limits on DOF work only on bones that are part of an IK chain. Make a 2-bone arm with an IK constraint on the last bone. Select the other bone in Pose Mode and in the F9->Armature Bones panel you can set its X and Z limits to min -90 and max +90. This limits the bone’s rotation to a hemisphere which you can see from the red and blue arcs in 3d view. The Y-limit is for rotations about the bone’s own long axis. The limits are relative to the original orientation of the bone so for a real armature you would use different values.

I apologize that I can cannot provide an image. Is this what you are looking for?

It seems impossible to create the desired DoF shape. (Might that be a future feature – Painted DoF regions? Customized?)

Anyways, I’ve restricted the mobility of my upper arms to a single hemisphere which is exclusive of the volume occupied by the torso. This approximates what I need.

Again, thank you for your input!

Bob