Tails and Trunks

[Dichotomy]

so... you want the truck to stay put when you move the head? like IK? but I assume that you want the back of the truck (ie the closest to the head) to move with the head right? You might need a few layers of controls for that. You could set up the clusters, and then setup like two or three controls that are above those clusters and make those move in relation to the head, forcing the lower clusters to behave certain ways. If you want a good FK feel with IK ability, try skining the ik curve to the FK joints, so when the fk bends, so does the ik spline and the ik bones (this is a little tricky with clusters, but I've had it work really well).
There are a good number of ways you can set this up. If you can, I would define what EXACTLY the character has to do, then work from that.

[Alfons]

Hi

I don't know if this is a perfect solution but my first thought was to create a regular IK handle from the base to the tip. Set the IK blend on the spline IK handle to 0 and key the regular IK handle. Know you can move the head and the tip doesn't move. There will probaly be some problems when you want to switch back to the SplineIK.

Cheers and Good Luck
Alfons

[kedma]

ı suppose, ı have a same problem. but ı dont have an idea about the solution. and ı want to learn how to fixed.
sorry for my bad eng:D .
http://img470.imageshack.us/img470/3151/fok0bo.jpg

[captainboom]

Global

I am working on an elephant rig (http://jmcarthurshead.blogspot.com/) right now for kicks, I set the Truck up with simple fk ctrl ,but it not enough ,it would work great if had the elephant eating a peanut or something. I am trying a ik spine to see how it works a well a messing around with dynamic IK to see how that works as well. just a couple ideas of my approach to the rig I will let you know how it turns out and what worked best for the rig..
http://www.sito.org/id/mca/elley.jpg


LATER
JASON

[Global]

Thanks for response.

[Dichotomy] - Great advice, thanks very much! I spent some time and redid the trunk today. It's looking better and all the basics are in now (I now have 4 trunks so to speak, with the Skinned joints constrained between FK, SplineIK, and an IK handle from base to tip)

Layering sounds like a good plan though, maybe have the splineIK controls linked to joints in the IK handle trunk. One issue though is that the bones will still slide along that curve...

[Alfons] - Thanks for the tip, not sure I quite get that about the IKBlend to 0... doesn't that just turn it off? I'll have a look at that tomorrow.

[Kedma] - I am not sure I understand your problem. Does this happen when you move your character? If so, it may be a problem with the cluster handles - open the attribute editor and see if 'relative' is checked on the handles. I hope that helps :)

[captainboom] - Keep me up to date with that... I wish I was doing this just for kicks lol! Btw, you may want to have a look again at the front leg setup you have there. It looks to me that you need another bone from shoulder to ankle. I'd be interested to see how the dynamic trunk comes along ;)

[Global]

Just to show you [CaptainBoom] what I mean

http://global.theonlyt.com/gallery/dump/elley.jpg

Ignoring the bottom arrow, that is pretty close to how an elephants bones look (though the shoulder blade starts a little higher...) The front 'knee' is actually a lot lower that you think - I was surprised when I looked into it.

[Dichotomy]

it almost sounds like you want a dynamic curve in the IK, controlling the joints, so that it moves with the head, but deforms like it is stretching out, and keeping the joints from "sliding" on the curve. I think you could get that with clusters, point contstrained to some upper controls, so that when the upper controls get stretched apart, the spline straightens, and the bones can't "slide" along a curve, because the curve will straighten. It might be worth it to put in clusters, then group each one individually, then contrain to the groups, thus allowing you to still animate the clusters individually. Justa thought.

[kedma]

thanks, ı am pleased for help:)

http://img324.imageshack.us/img324/3484/fil7pp.jpg

[Global]

Thanks for that Kedma - nice bones.

And thanks also to Dichotomy, great tips... and that's pretty much how my trunk ended up.

Essentially I have 5 trunks now and 5 levels of control. Trunk_BIND (ie. what the mesh will be skinned to) is constrained between an IK, an FK, a SplineIK, and a dynamically driven spline. The SplineIK has 6 Clusters as controls and each cluster handle is constrained between joints in the IK trunk and 'world' space (So I can have the trunk positioned in using the spline IK handles but it's still locked to the IKHandle and straightens out when the head is moved).

It'll soon be time to skin and do some animation tests... just hope it goes ok as I really don't want to have to go back to the drawing board! :S

Thanks again.

[ankheilw]

It looks like you guys have a pretty solid hold on the controls for the trunk, but I'd like to suggest using Maya Hair as a control for the dynamic trunk. I used to use a series of constrained clusters to create dynamic follow-through, attached to joints, but with hair it is amazingly simple and takes a lot less time to set up. This would give you a straight-forward option if you just wanted the trunk to hang realistically or to follow the head. You could add it into your blending system in place of the clusters.

Just a thought, hope that helps. I'd love to see a post of the final solution.

Good Luck

Woody

[Global]

Thanks ankheilw. I should have said that the dynamically driven trunk is actually a joint system set up using hair (one of the guys at work showed me how to do that - So I had a lot of fun with the interactive display and swinging the head from side to side :))

Seems to work quite well - though the only problem I can see doing it this way is shaping the trunk into a position that I want the dynamics to take over from (say, have the trunk posed in a raised position... then let it drop dynamically from that position) Maybe I'll get that sorted; there is so much more to learn about Maya rigging and I've already gone waaay beyond what I could do in Max! I didn't realise rigging could be so much fun! Well... a headachy, growling at the screen kinda fun anyway - hehe)

As for seeing the final - well I'd love to but it's for a commercial project (I'll see if I can twist the boss's arm to at least let me post images of the rig minus the model)

[seven6ty]

Hey there, sorry I got to this a bit late, but about a year ago or so I was doing the exact same thing. I settled on pretty much the same approach as you, only not quite so many skeletons. I had the bind rig, the FK and then the spline IK driven rig. The spline IK driven rig had an attribute on it that allowed you to switch on or off, the dynamic spline control. So you could set it to 1 and have the dynamics completely take over, or you could have it at .5, so it was split between the spline IK and dynamic spline IK setup... Then I believe you could also blend between having the FK and spline IK/dynamic spline IK setup, which worked nicely. I hunted my ass off online for tutorials and such relating to this, but the best reference I found was a tutorial out of a book, "Inside Maya 5", by Adams, Miller and Sims. It goes over pretty much this exact setup and gives you a very indepth description of the proper parenting methods and so on and so forth, so that this kind of setup becomes modular and can be placed into just about any rig for tails, ears, trunks, etc.

It's also nice as well, for my bind skeleton, I had one joint for every horizontal ring of poly vertex detail, so that weighting was direct and easy. This gave me 13 joints in all. Then my FK and spline IK joint chains were something like 7 joints in all, which drove a curve which the 13 joint chain was bound to. This gave me fewer control joints which would pass on their control to the higher res, 13 joint chain very well.

Sorry it's so late, but yeah, fun stuff!

[Global]

Thanks seven6ty - you may have been late but the info was very useful. The rig was finished but I was put on to something urgent for a few days and didn't have a chance to do a test anim until Thurs / Fri. I'll be concentrating on the trunk anim tomorrow but my initial thoughts on it are that I may have to tweak it some. I like the idea of a blend between splineIK and the dynamics (at the mo I have the SplineIK controlers with a blend to the 'normal' IK trunk - meaning I can have parts of the spline IK trunk stay put) But I'm still not too happy with the dynamic trunk as I can't quite figure a way to initially pose it and then have it dynamically drop from that pose.

I'm curious as to how you [seven6ty] linked up the 13 bind joints to 7 FK joints and still maintained a nice curve (I may be missing something basic here :))

But thanks again to all for your suggestions - It does seem that tut's (or rough guides even) on trunk setup is pretty hard to come by (same goes for a nice quadruped setup *Global sublty hints for any quadruped links you people may have*)

ciao ciao

[utpal]

what seven6ty means, is that he makes a joint heirarchy with 13 joints. then, he applies IkSplineHndle to it. then, he makes another joint heirarchy that will have fewer (4 or 5) joints, by Curve-snapping to the Curve of the IkSplineHandle. then, you smooth-skin bind the curve of the IkSplineHandle to the new joint heirarchy.
this way, the heirarchy with the fewer joints drives the curve, which drives the 13-joint spine heirarchy through the IKSplineHandle.

ps. don't forget to deselect the "auto simplify curve" option before creating the spline handle..

"inside maya's a nice book.

:love:

[CGTalk Moderation]

This thread has been automatically closed as it remained inactive for 12 months. If you wish to continue the discussion, please create a new thread in the appropriate forum.