Does anyone know?

What do you mean by a “Null Controller”.

Is it an aim (lookat) constraint or you want to hang the bone off a partial transform from a “Null” or you want to have the bone driven by a local position or a world position?

More specifics please.

I'm trying to use a Null for a controller and am not sure if that's the right node to use.

Anyway, what i'm trying to achieve is to make a controller that would drive a bone/s (e.g. a finger controller or a knee controller). I'm used to rigging in Maya, and I'm just starting to learn rigging in Houdini.

Let me know if anything is still unclear.

Nulls are the right object type to use to drive bones.

My main problem is how do I make the Null Object drive a Bone?

here is a little file with three types of setups

1 - standard 2 bone IK, null to control bones, null to control twist
2 - one bone IK
3 - FK bone (you don't need a null for this but…)

there is good info in the docs about this and plenty of third party vids about it - check out www.3dbuzz.com

Thanks arctor! That's what I was looking for.

IK solution since to be pretty straightforward since a controller is automatically provided when you create a bone.

But for an FK bone, the FK bone should be the child of the Null Controller (and the node connection should display this as well). Is this always the case if one wants a controller for an FK solution?

as I said in my post for FK you don't need the null, or any other object to control an FK bone - since in Houdini bones are actual objects - you could just allow the animator to select the bone and rotate it…

having nulls as parents of FK bones gives you some flexibility in setting up things like finger curls etc…


HTH