Follow Curve Kinematic

[TheUsualAlex]

Have any one here used Follow Curve Kinematics yet? I have only played with it. I find it somewhat difficult to control even by moving the curve points and such...

In what case scenerio would you use Follow Curve?

THanks,

Alex

[danteA]

I would presume tails and such things? How is it different from spline ik?

[TheUsualAlex]

I thought that for something like tail, using Miguel's CHOPs method or simply use 1 channel to control the same channel on the subsequent chain (ch()) would work a lot better, won't it?

I hardly ever use spline IK... I am looking into it.

[sirogi]

er..I'm no character guy, but I did use it before for back spines (y'know... the spinal column) and instead of pushing and pulling points, I did do a blend on multiple "poses" of the curve (slouched, straight, left to right, etc....) knida worked....guess it's only useful if you have a bunch of bones you want to animate in a "creative" way....if too tedious to animate them individually...

seems like keyframed tentacles would also be good, althought, I'd try to find some procedural way first... of course....

it all really depends on what you want to do.....

my 2e-10 c.

umm...yea, like Dante said, how is it different from spline ik?

[Lukich]

I'm using it ti animate a movement of a snake that slides along the curve. Works great!

[thekenny]

actually the biggest hurdle to over come using the IK on a curve solution is maintaining the initial length of the curve. the default nature of the solution tends to make the the IK chain slide and extend off the length of the curve depending on how you make it.

my solution has been to make one bone network, any solution other than curve, and plant AddSops to each bone in the chain to define the root and the tip of the bone. it's easy to do this procedurally as well, since the bones are made from Sops to begin with.

i would object merge each pt in order in a new GEOop and then use an final AddSOP to stitch them together, you can make it a spline if you wish with polySpline, Fit, or convert. resample will work as well but i prefer the polySpine.

then you take the final result and fit a higher density bone chain to that curve. you never animate the high rez chain, just the low rez one and you will never get the bones to slide off the end of the curve.

how's that

-k

[edward]

Hey Ken,

That is by far the smartest technique I've seen so far! Maybe we should make up a tutorial for this.

[thekenny]

thanks

i was trying to figure out the isner spine in XSI, not that i can easily do that since it only have the webpage to go by. it exists as an addon for XSI and the free learning version doesn't allow you do add addons.

but it is kinda based on something i would do in soft to make setups easier to work with. you would double up on an ik solution for a leg in order to it simplier to animate but yet you would get the deformation you wanted. example, say you had a very slender tubE leg you wanted to deform but not with a kink in the middle. i would make two ik chains one two bones, the other as many as needed to get the leg right, say twenty bones. both chains would share the same goal and the higher rez chain would be the deformer for the leg.

back to the spine setup. i was wondering if i could use this set up and chain the weight of the chest or pelvis somehow. the isner spine is very neat everyone should take a look at it.

http://www.isner.com/isnerspine/spine_introduction.htm

sounds good, but again i've never used it.

i'm very sure someone can cook up a similar solution in houdini.

-k