distance constraint to joint?

[Deep Wulf]

I'm working on a character rig, and have an idea for a setup to control head swivel easily.

However, I need to know if I can, and how to, create a "distance" constraint, so that a small piece of geometry maintains a specific distance from a joint at all times.

I'm using Maya 6, and any help would be greatly appreciated!

Thanks

[Black]

I have to ask a few questions to see if I got it correctly;
Are you trying to get sort of like a drunk's head swivel? By sort of limiting the transform/rotation?
Or are you tryng to set a dynamic that gives a secondary animation? So the head swivels as it walks, without any extra efforts?

Maintaining an equal distance from an object is not a challenge.. you already answered it yourself. If you are asking if you can limit the secondary animation into this specified distance. That is another matter. Actually not too basic either.

In any case. I couldn't capture how you are relating all of these to each other, and what you intend on doing.
Can you be a bit more detailed on the question?

[Deep Wulf]

I intend to distance constrain a small peice of Geometry to a joint, first, and then intend to aim constraint the joint so that it rotates as I move the geometry.

The aim constraint is fine- but what I need is something to ensure the geometry always maintains the same position, distance wise, relative to the joint, so as I animate the character, the geometry doesn't "float away".

The end result (I hope) would be to have a "handle" that I could use to rotate the character's head wherever I need it to be w/out having to grab joints within the surface. Kind of like the handle on the tripod of a camera.

[Black]

so you want a control rig set up?

Well there are many ways to do that. The simplest and easiest way that comes to mind is to simply parent it to the joint. Where ever the joint goes.. so does the locator/curve.

What I do is create a camera for the head, parent it to the head.. a camera for the hands and feet. And parent them accordingly. The I prepare a variaty of curves that trace out the features of the face, segments of the hands and feet.
Then parent these sets of curves to the specified camera. So when you move the camera around you always have a heads up display of the features intfront of you.(A good workflow would be to have all the mager motion done with the render cam and not the final retouches. So you would be seing the face only on the head cam and the feet in the feet cam etc...)

And like insde the little boxe representing the hand. I place a locator and limit it's movement to only 1 unit up and down.. and 1.5 units to the sides (Limited the translation values in the attribute and locked and hid the rest) and then parented them to the box they were indside of.
Applied set driven keys on them. So when I select and move the locator along the segment. I get a bend; When I move it up or down.. I get a twist on the particular finger joint.
since you have a dial.. there are alot of inbetween thresholds that are not as easy to obtain by manually animating.

Thi is just an example that can help you get an idea on how you can find ways to select and control things. There is a variaty of rig preperations on the matter. You may want to dig into them.

Hope this can give you some kind of a variaty. But to keep things simple, you may preffer to just parent the handle to the joints.. all the same.