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ShadowMystic
02-09-2012, 07:41 PM
So, I was experimenting with rigging. I'm not new to rigging, but I am new to rigging nuances. With a combination of rotation limits, one IK target, and one pole object, I have created a rig that, at first, appears quite solid. I haven't had a chance to test it, but I plan to soon.

Now, I was wondering if anyone else uses this method or one similar.Maybe, you use one you find better, more stable, and faster. Please, comment on trials, tips, tricks, and tribulations on the troubles of creating predictable IK rig in actual productions. (i.e. no popping.)

I'm interested in all experiences. I am young and intend to be a 3D sponge even if, someday, I must--ack-- learn MAX or Maya...

metahumanity
02-10-2012, 05:05 AM
So, I was experimenting with rigging. I'm not new to rigging, but I am new to rigging nuances. With a combination of rotation limits, one IK target, and one pole object, I have created a rig that, at first, appears quite solid. I haven't had a chance to test it, but I plan to soon.

Now, I was wondering if anyone else uses this method or one similar.Maybe, you use one you find better, more stable, and faster. Please, comment on trials, tips, tricks, and tribulations on the troubles of creating predictable IK rig in actual productions. (i.e. no popping.)

I'm interested in all experiences. I am young and intend to be a 3D sponge even if, someday, I must--ack-- learn MAX or Maya...

It would help to start this discussion if we could see the rig you came up with. Video? Screens? File?

Anyway, the hardest thing to get right in a shoulder rig are the deformations, IMO. IK is more of a technical aspect and quite easy to set up.

One golden rule is to keep IK solutions limited to 2d by separating the axes.

RebelHill
02-10-2012, 05:25 AM
An IK rig for arms/legs, is basically the same, and you shouldnt need much, or even anything in the way of limits, etc to get it to behave. A regular 2D IK chain with an IKplane parent will give u totally solid IK that wont pop or flip or anything.

As for deformations, depending on your character, a simple one point joint with good weighting can often be good enough for simpler cartoony folks, whereas the 2 bone bridge works a treat for realistic characters.

http://forums.newtek.com/showthread.php?t=107462

ShadowMystic
02-10-2012, 10:22 AM
Example of my rig.

I usually control deformation with overlapping weight maps.

I haven't worked on a hyper realistic human character as of yet.

RebelHill
02-10-2012, 12:01 PM
eek... thats pretty far from stable.

you need to use a parent bone (for ik plane) which targets the goal, then the bones themselves only have IK on one axis (planar/2D IK)... then it'll work.

The make joint chain script cerates an example of this setup.

ShadowMystic
02-10-2012, 12:34 PM
eek... thats pretty far from stable.

you need to use a parent bone (for ik plane) which targets the goal, then the bones themselves only have IK on one axis (planar/2D IK)... then it'll work.

The make joint chain script cerates an example of this setup.

Perhaps it is not as stable as something from "rhiggit', but it has been working for my needs so far. IK has no problem calculating two axis for the top of the chain, and the Pole controlling bank helps me solidify the elbow direction. With the limits as back-up, I've had no troubles yet. I'll see from more extensive use.

ShadowMystic
02-10-2012, 12:49 PM
Also, by what benchmark do you determine stability of a setup? Do you have a set of poses you need to hit easily, animation sequences that you test with, or just playing with it to see what it does? If the first two, could you post some examples as well as an example of the setup that you are describing.

RebelHill
02-10-2012, 01:12 PM
move your goal null round a bit and twist your arm... the wrist comes away from the goal, it doesnt lock, thats what I mean by unstable in this sense... the 2channel IK on a single bone the way you have it cant and wont resolve properly... no matter what u do. Trust me.

And determining the stability... u move it about a bit, it either works, or it dont, there's no kinda set test.

ShadowMystic
02-15-2012, 11:08 PM
I've been playing with Rhiggit samples and they take 'stable' to a different level. There's stable enough to do a few short sequences and theres really stable. Unfortunately, I'm missing something to activate the arm IKs. Therefore, I'm working on how I want to firmly plant a hand and have the arm follow. TBD

RebelHill
02-16-2012, 04:14 AM
Nope, the IK setup used in my rigs is plain ol 2dIK... nothing special or secret.

Create your IK as a 2D (planar) system (which means IK on one channel only), and create a parent item (IK offset/plane) which targets the goal.