Dynamic Hoses... it's got to work, dammit!

Support Animation and Rigging
1

Hi, I’m trying to recreate a dynamic hose built in a Maya tutorial. I think it can be done in blender, I’m >< this close to figuring it out but I’m stumped. The step I’m on in the tutorial goes like this:

Select the 2 CVs on the left end of your nurbs curve and make it a cluster (clus_01), select the 2 CVs on the right end and make them a cluster (clus_02), now select the center CV and make it a cluster (clus_03). Select clus_01 and point constrain it to clus_03. Select clus_02 and point constrain it to clus_03. Set both constraints to 0.5.

I have a nurbs curve (7 knots total), an empty on each end and one empty on the center knot. I want to parent the 3 knots on each end to their respective empties and parent the center knot to its respective emtpy, then parent the empties to cubes so that when I move the cubes the curve ends move. when I make a “vertex parent” the empty is parented to the knots:

3 knots (nurbs curve)
|
|_empty

So, if I move the empty it moves but the knots don’t. If I go into Edit mode and move the knots, the empty moves. I want to move the empty and IT moves the verts (in object mode).

empty
|
|_3 knots (nurbs curve)

You can do this with hooks but the problem is, is that when you move the hook, its pivot point does not move, instead you get the long dashed line that follows the hook around. If you want to make the hook fully mobile, you have to parent the hook to the mesh it’s hooked into. Enter the catch-22. You can move the hook and make it move the curve. You can move the curve to move the hook. However, if you wanted to connect the curve (via effector cubes) to different objects (like the upper and lower parts of a mechanical arm or something like that, that may be moving around) you can’t, because you can’t parent one object to multiple parents. That’s my dilemma.

I have tried vertex parenting, but it works in reverse of what I am trying to do. I have been scanning posts for two days looking for an answer and seen other people ask almost the exact same question and get the “make a vertex parent” answer. It doesn’t work. If there’s a way to vertex parent in reverse, please tell me, because I can’t seem to find how to do that anywhere.

thanks,
Gendo

2

Hi, I used a bezier curve with two points, beveled the curve with a bezier circle, added a hook to each end and then parented each hook to its cube.

Was this the robot tutorial in “3d world” magazine?

Heres a mpg of what I mean:
http://www.thehive.se//images/pipe.jpg

dynamic_pipes.blend

Hope it helps.

/nozzy

3

thanks, it looks good. i had done the exact same setup, but the problem i had and it’s in your blend as well, is that the hook “centers” don’t move with the hook mesh. i tried parenting the hook cube to another cube but the hook’s center still doesn’t move. now, if this is part of a robot or something that moves around, the hook center is going to have these huge lines all over the scene trailing back to their original centers. that is what i was trying to figure out, how to get the hook’s center to move with the mesh. thanks for the effort though.

-G

4

where’s the problem? simply parent the hooks and the hooked object the robot.