Quadruped Rigging Techniques

THIS THREAD IS CLOSED, PLEASE CONTINUE DISCUSSIONS IN this thread.

This thread began here http://blenderartists.org/forum/showthread.php?p=1386378
But I would like to start a new thread with a more focused discussion.

http://imgur.com/7vxjd.gif

I am interested to know what solutions can be designed for a quadruped rig. To start this thread, I have taken Catboy85’s original model, and designed a new rig for it. I did this because I found the original rig very hard to use, and I could see many ways in which it could be both simplified and enhanced. I will add here that Catboy85 did an excellent job on his model and rig! I am just wanting to take it further…

The animation above is a test animation to show the versatility of the new design. It was done quickly, and the skin is completely default weighting. It is just meant to show the capability of the rig, as that is what I want to discuss: versatile solutions for control and solver setups on quadruped character rigs. This is not a thread about animation, weight painting, or even horses necessarily. I am looking for the ‘ideal solution’, and I hope the more skilled riggers out there will join me :slight_smile:

A little bit about my setup:
->Control bones on layer 1, Deform bones on layer 2, Mechanism bones on layer 3
->Rig is designed based on relation to human anatomy
Some flaws:

  • Moving the body around, the legs still point up - they don’t tilt like you would expect. This also makes it difficult to keep the feet in place when the horse leans, because in order to tilt the leg it has to be rotated in FK.
  • It is very easy to put the body into a position the shoulders and hips can’t handle.

This thread is intended to be a community resource for rigging techniques on quadruped characters. To minimize the reading, I will do my best to update this post with the latest versions, and submitted examples!

Updates:
RIGS:
Horse Rig (Latest Version) [post]
Mikahl quad dog[post]
EXAMPLES:
Pepeland Dual Armature Leg Rig [post]
Dual Armature Simple Example [post]

Attachments

HorseRig_animated_catboy85-FGC.blend (945 KB)

http://imgur.com/pIzm1.jpg

Okay, so I’ve spent more time on this solution. I’m much happier with it, fixed all the problems with the last one…

such as:
-The leg controls are still very easy to work with, and the hooves themselves stay on the ground when the body is moved.
-The torso controls are much more versatile, and flexible.
-The tail is a simple 1-2 animation (put it in the position you want with the first control, and then adjust the curve with the second… this makes for very simple secondary animation!)
-The neck behaves much more appropriately now… yet I feel it could be better, if not just needing deform bones or shape key fixes for some positions.

The skin is still default weighting (except for a necessary fix on the chest, and behind the ears). The controls are bright and colourful :smiley: I couldn’t help it, I was playing around with the shapes :slight_smile:

Any suggestions or alternate solutions would still be very much appreciated. I would be very interested to see alternative ideas! Especially different setups for the head and neck… that part took the longest, and I feel it could be better.

Once again Control bones layer 1, Deform bones layer 2, Mechanism bones layer 3
and still naming the parts as they relate to human anatomy (I find it much easier to solve and think about that way).
Also, the knees and shoulders are best manipulated using free rotate (double tap “r”), and the legs now involve an additional offset control which should be pointed up the axis of the leg when the feet are not planted on the ground.

I did try creating the root at the shoulders going down back towards the hips, but as soon as I did I realized it wasn’t a good idea! LOL but I’d be very interested to see a solution making that work! :smiley:

I’ve actually decided I won’t be doing an animation with a horse now, as I have other projects I would much rather focus on… so my work with the creature is done UNLESS someone posts suggestions to this thread ;). I would still be interested in playing with solutions for the rig :slight_smile: But I won’t be animating it or anything…

Actually I think it would be a really neat idea if someone else animated it… :smiley: Catboy85 did the model, feelgoodcomics did the rigging, ____ did the animating, and _____ did the texturing and rendering! That would be a beautiful demonstration of the power of the open-source community! :smiley: Atleast I think so… :slight_smile:

Anyways, the new version is attached, and I will keep an eye on this thread for new ideas :slight_smile:

Attachments

HorseRig_IK_catboy85-FGC.blend (968 KB)

Gord,

Very nice job !

You are a rigging machine ! … and a fast learner !!! … just how long have you been using Blender :eek:

Couple of minor suggestions :

  1. Create a group with all the components of the rig, mesh, shapes etc, then the whole thing can be appended from the base file using the group “tree”.

  2. Personal preference only, but I like to to put the mesh(es) of a character on a layer 1-10, (top row of layer buttons) with the armature on the corresponding 11-20 layer (bottom layer), then you can use the number keys (not the numpad), to hide /show the mesh, and ALT-(sameNum) to hide / display the armature.

Mike

Thanks Mike :smiley:

I’ve been using Blender since I graduated April 2008. But I’ve been rigging in Maya for 3 years now in college. And yes I am still learning, and yes I suppose I am quick at it :wink: Yet I sincerely believe anyone can learn quickly, it’s just a matter of finding a clear enough explanation… because once you know… you know, you know? lol :slight_smile:

I owe the bulk of my understanding of rigging in Blender to the Mancandy DVD and the BBB rigging clip. But my knowledge on solving rigs comes from my schooling, and having access to the entire “Learning Maya” materials (and I do mean all of it, including material that wasn’t released yet!) for a year while working at Autodesk in Toronto.

Thanks for the tips! :slight_smile: I wasn’t thinking about appending the rig, I was just thinking about the rig itself. But grouping would certainly be a good idea for using it. And the layers is a good idea too, though my personal preference is having the armature and rig on layer 1 and 2 so I can hold shift with my pinky and tap them quick with my middle finger :wink:

Speaking of learning, I just discovered this leg rig “tutorial” by Daniel Martinez Laraand I am not able to find the deform bones in the file (broken link at blendernation). I’ve not seen 2 separate armatures used together before… and it hadn’t crossed my mind. My curiosity is piqued! Do you know where I could find more information on how this is setup?

Edit: Silly me, I just found the deform bones on the other armature! Lol… all day rigging makes your brain gooey :slight_smile:

Okay, so it turns out the setup on the leg is identical to the one from the tutorial I posted earlier which is adapted from “The Art of Rigging”. Except that instead of making bones for groups he just parented the IK handles to eachother… which is really slick! :wink:

Corrected in later post
The 2nd armature is redundant, as it would be just as well to put those bones on a separate bone layer. The 2nd armature drives bones from the first armature through copy location/rotation contraints. I imagine he did this before bone layers were implemented… which would make sense. For a second there I was all excited about a new technique :eek: lol. But it is a VERY clever solution for not having bone layers, I will say! :cool:

Edit: I just noticed there are bone layers used! the setup seems to be for the purpose of changing the pivot of the foot! very cool!**


Anyways, back to the topic at hand. If you guys/girls have any suggestions or ideas for quad rigging, please post them to this thread! It would be nice to even post setups for creatures other than horses, like lizards and such…

OR if you want to animate the horse, and render it out, that would be super cool too! :RocknRoll:

Hey feelgoodcomics. I may come back to this thread later, when I have the time to mess around with the rig, but first I just wanted to comment on this:

I don’t know for sure what pepeland used his second armature for, but I wonder if it’s similar to what I did with the BBB rigs (well, except for Rinky, which I rigged first while I was still learning).

Each character actually has two rigs (although I put them in the same armature):

  1. The deformation rig. It does all of the deformations on the character. And that is its sole purpose. It isn’t ever supposed to be directly touched by the animator. No fancy controls, just raw “get it to deform right”.

  2. The control rig. Its sole purpose is to be used by the animator to animate. It controls the deformation rig through constraints. This never directly affects the mesh. It only affects the deformation rig (which in turn deforms the character).

This separation is really useful in at least two ways:

First is that it lets me focus on one problem at a time: deformations, and user interface. They really are separate problems, so treating them as such in the rig helps me keep my brain right and my goals and focus clear. It’s great to be able to experiment with control schemes without worrying about deformation problems, and vice-versa. It actually make things easier to think about.

Second is that it makes the rig more maintainable for production use. In a production you have to make fixes to the rig even after animation has already been done with it. Keeping the deformations and controls separate allows me to fix deformation problems without fear of changing how the controls behave. And if things get really messy, I can even insert a third layer to negotiate between the deformation and controls, to preserve the behavior of the controls.
But if the deformations and controls are intertwined using the same bones, those kinds of problems can be huge nightmares, requiring animation to be done over.

Hi Cessen! :smiley:

I’m glad you’re interested in tinkering with quad characters, I would be delighted to see what solutions you would come up with! When you have the time of course :yes:

I anticipated this thread would be ongoing for quite sometime… years even! As Blender changes, the design of a quad rig probably would too… I wanted to have an open ‘brainstorm’, if you will, to find effective solutions - where the community can access them for reference, or contribute to them further!

And I appreciate your explanation about the layered armatures! I noticed that technique in your video and it’s a really good idea! I will definitely be doing that on future production rigs!

I was messing around with Pepeland’s leg a little more after my edit, and tried merging the two armatures together… the behaviour is the same - the pivot can still be relocated. The first armature is the deform rig, and the second armature contains 2 control bones that are directly controlling bones in the first armature… hence the redunancy. Very cool of course, but I don’t see the necessity of a second armature, since all you can use it for is constraining bones on the first armature. I think using separate bone layers is just as good :slight_smile:

Edit: I just figured out why he did 2 armatures… it is to be able to directly drive the IPO! You can’t use a bone within the same object (ie armature) as a driver in the IPO. So the second armature is for the purpose of hooking up direct drivers! I’m excited! :smiley:

I briefly checked out your blend, I like it. The animation is super good, but also super clean! Its nice
to see good work come from minimal keyframes.

Personally, I prefer rigging with two separate armatures altogether. I actually just wrote
a blog post about why here.It has further reasons to use multi-armatures, in addition to what Cessen mentioned.
And I don’t see the need for CTRL to prefix all your controlling bones. I’m of the mentality that every bone the animator can use, has no prefix. But if its not meant for the animator, it gets a prefix, aka DEF, IK, etc.

For what its worth, I also have aquadruped rig, if you want to dissect something else. Although I’m not particularly proud of it.

Thanks Mikahl :slight_smile:

Funny enough I didn’t know how to properly approach animation in 3D until watching the Blender Character Animation DVD! I was previously working one part of the character at a time, instead of blocking in the main action, and tweaking it… so I’m really glad to have a better approach :smiley: lol

edit: I just want to add that the animation was 7 frames taken from a muybridge sequence found at the back of the first animation book I got when I was a kid “How to Animate Film Cartoons” by Preston Blair :slight_smile:

The naming is also a good idea! I was naming for myself, to keep track of what was for what at a glance… if I saw “CTRL” I didn’t need to read further. But you’re right, a good rig makes things easy for the animator (although doesn’t do things FOR the animator I will add - that usually leads to unnecessary complexity, and is why I chose to make the knees and shoulders FK).

Your rig is very cool :smiley: He’s a cute little guy! I will be fiddling around with his bones for sure! I like how you have the torso pivot in the center. Though I don’t know if that would work on a horse because of the length of it’s body, but it’s worth a try!

I just edited my previous post, as I realized multiple armatures allow you to setup direct drivers in the IPO (ie. instead of action constraints). I’ve attached a sample .blend to demonstrate it simply. Pepeland’s file demonstrates this in a more advanced way.

I’m feeling like I should redesign the rig based on the suggestions so far, and experiment with multiple armatures… I’ll see what I can cook up :slight_smile:

Attachments

IPOdriver_DualArmature.blend (81.8 KB)

Okay, I’ve been messing around with dual armatures, as well as having a separate set of ‘mediator’ bones, and my conclusion is this:

It’s awesome :eek: BUT it’s not a good idea for this thread!

The reason being that it:
1.)doubles the armature data (making the file over 1MB in size, and therefore unattachable), and
2.)it creates redundant bones… which is fine when you’re doing your own setup and need to be able to make changes without losing animation, but when you’re trying to make a quick rig that others can easily understand and alter, it makes it needlessly confusing!

The skinning is default anyways, and as I mentioned we’re not concerned with animation here… atleast not at this point :wink:

I like that in my previous example you can just press layer 1, 2, or 3 and easily decipher how the rig was constructed. You don’t have to jump armatures or figure out which layer is which. However, if I were designing the rig from scratch I would make my control bones completely in a separate armature. This would be ideal for the tail setup as well, since I wouldn’t need to use the action constraints, but could drive the motion directly instead! Keeping the action editor clean and tidy for the animator to do their work :eyebrowlift:

However that being said, I really appreciate the feedback so far! These are great ideas, and good to know how to do! I’ve already learned tons about rig setups in Blender (and about grouping bones, your file revealed that gem to me too Mikahl so thanks :D). Maybe when the mechanics of the rig are figured out, we can come back to these issues and produce a nice polished easy to use horse rig for the community to use :yes:.

But first I would like to step back and explore more mechanical solutions before the animation or user interface is even considered! Particularly ideas for the neck. If any of you find time to come up with an idea for a design (even just an armature with only the head and neck) and post the blend file that would be awesome! As I mentioned, I no longer need this for a project, so my interest in it is now completely nerdy :cool:

(note: I have disabled the deform option on bones for layers 1 and 3… this is done VERY easily by activating those layers, selecting all the bones, and pressing “shift+w->deform”. Now the horse can be re-skinned and only the bones on layer 2 with deform enabled will affect it :D.
SO just a tip, before making alterations to the rig, set layers 1 and 3 to deform… this will mess up the skinning but it will make it easier when you are done making changes to quickly set all bones back to non-deform
;))

Sorry for the spam post, but I am merging this thread into the other one, as I find this thread to now be redundant. Please visit the other thread to continue discussion.