Can't find anything on good quadruped rigging

Hey all,

Last year I sent a question on rigging a horse i modelled, in such a way that would let me control ribs and hips without moving the rest of the upper body like if it was a root. But instead hips that can be liften and rotated during a run, or cage that can sqay left and right only affecting the nearest parts like a real body does.

I was looking at some maya tutorials and this is something I’ve also been searching for (the curve/nurbs controls) So far I was unable to find that in blender either.

I tried watching maya tutorials which are much more numerous than here, but lot of the important bits don’t translate (at least with my knowledge of blender)

I plan to have a rig done for horse and a dragon, so any tips for a more natural rig would be greatly appreciated. I know there’s a riggify but I want to learn to make my own.

Thanks

I have a spline spine for Blender rig demo file in my signature that will work ideally for this. Its a Blender version of the classic Maya ribbon spine crossed with the advanced IK twist method. But using two splines as the ribbon rather than a nurbs surface. There are some text instructions in the file. So working with that, it should be straight forward to folllow a typical Maya Quadraped tutorial and translate the methods across. The principles and result will be pretty much identical.

I have one rig where I used this system in my Blender work thread. Its not actually a quadraped but a small theropod dinosaur, but it demonstrates the method used in an actual rig. Anyway all the best.


My big cat rig uses very straightforward armature building methods, and is based on a real-world big cat skeleton in terms of bone arrangements and articulations. I was able to build in a lot of bone interactivity without requiring special controls or methodology, while also preserving manual adjustment for all principal deforming bones. If you want to build your own rig for this kind of thing, I suggest 1) studying the animals you want to emulate, and 2) build & test, build and test, and learn what rigs can do from the ground up. Sometimes simple is best (the KISS principle).

I got no problem building an accurate skeleton. I just don’t know how to make those controls outside of bones to move it around properly like in your sample. Especially the hip and cage sway motions (up down left and right) Can you point me to some tutorial on it?

Sorry I missed this reply/question. Truthfully I don’t know of any tutorials because I did not use any to learn rigging, I just did it. I have studied other peoples’ rigs to my benefit, and am willing to return the favor. Attached is my Big Cat Rig version 1.0, not the final version but serviceable and illustrates my methods. In short, the rig uses very little in terms of “controls” – most of what you see are just bones that use Shapes for ease of identification & grabbing when animating. In the tail section, I have used Empties & hooks to animate the spline IK system, probably the most complex part of the rig, but it’s pretty basic even so. The rest is just IK and a few Transformation constraints to automate the wrists a little.

BigCat1Rig01.blend (1.76 MB)

Use as you see fit, take it part & re-assemble it (those leftover parts? Ignore 'em! :wink: ), learn from it hopefully. Most of the interactions you see in its walk cycle are the result of specific construction details rather than any special control mechanisms. BTW the rig is set for a 36-frame walk cycle (see the Action Editor) but also has some other Actions you can try out, and the walk cycle has been extended to a much larger number of frames using strips in the NLA Editor – these are currently disabled.

Go nuts!

Thanks so much this is great. I guess I need to learn about some of those things like empties. I see you got some shapes for ear control but no rig there. Is that controlled just by that shape?

And yes you have the ribs and hips control how i want them. If I can find it I can show you my horse rig for comparison. Very stiff.

That shape is a bone, as are all the shapes in the rig except for a few empties here & there, as in the tail. The “shapes” are bones in disguise, so to speak. Any bone can be given a Shape, which changes its appearance but not its function.

First you’ll need the shapes to assign to bones – look on layer Alt+0 to find them in the Big Cat Rig file. They are just simple polygons, no faces, just edges, in some cases modeled specifically to reflect their purpose. They are named WGT-xxx, where WGT stands for “widget,” a convention I borrowed from the Sintel rig.

Any bone can be give any shape, but since part of their purpose is to make them useful, discretion is advised. First select the Armature, then in Properties>Object Data>Display check the “Shapes” box. Then in Pose Mode select a bone, and in Properties>Bone>Display find the “Custom Shapes” field and select a shape from the drop-down. The bone now looks like the selected polygon shape. The target shape’s orientation in 3D space determines how it will appear in the rig, so if you make your own you may have to play with it a little to get it looking perfect. The “At” field is optional – I’ve not used it but I assume it lets you place the shape somewhere other than where the selected bone is located.

The triangle I use for the cat’s ear bone shape is because cats’ ears are essentially triangles. Had the model been Mickey Mouse I likely would have used circles. That’s the basic philosophy behind using bone Shapes, a little extra visual perk to reduce bone clutter but no additional functionality.

Thanks I’ll play around with it. Right now I’m trying to make a new rig with root in the shoulder like in your model. It seems I might get more spine flexibility that way. There is one thing I’m curious about right now. When I try to control spine bend on your model i can do it freely without making the whole body rotate with it by pulling separate spine bones. Like if i need to bend it up or down in a run cycle. In my experience it goes from ( to l rather than ( to ) How is that accomplished?

Hi sythgara

I keep seeing this thread popping back up and you seem to be asking the same question each time which is… How to set up the controls for the most common sort of quadruped spine rig you see in most Maya rig demos.

You also are asking some very basic questions about rigging too so I would recommend perhaps getting thoroughly acquainted with the core principles of Blender rigging before attempting this. Nathan Vegdahl’s ‘Humane Rigging’ is the classic for this. There was also a Jack Russell Dog rigging course I saw appear on here a while back that looked really good and seemed to use a classic spline based spine method. So perhaps worth checking on that too. It was up on Blender market last I knew.

I’ve just sketched up a quick diagram showing the parenting set up in a classic quadruped spine set up. It’s a fairly basic set up once you know a bit of basic rigging. As I’ve seen these quadruped questions pop up in the past too I thought it might help to add a bit more to whats been said in case it helps out some others too. The parenting is shown by the red arrows.


In Maya this tends to be the way it’s always mostly done. The way you described and is illustrated in the video you first posted. One of the reasons for working this way is because it is far more straight forward when baking walks and runs to paths, as you essentially have a pantomime horse type of rig set up where each part can be controlled more or less separately to the other. Animals also can form some quite complex shapes in movement that can be hard to achieve without a great deal of finer control in the rig. Such as the very distinct sharp curve in a cats spine as it sits. Or the twisting and undulating spine of a fast running greyhound or cheetah.
I’ve always rigged quadrupeds this way in both Maya and 3DS Max. It most commonly uses a spline IK spine. Or sometimes in Maya whats called a ribbon spine that uses a nurbs surface for the twisting.

The problem transferring the common Maya method directly over to Blender is that Blender does not have an advanced twist control in it’s spline IK yet. This requires a work around by using a second spline as an aim object for each bone in the chain. This provides the twist. 3DS Max also had the same limitation and this is a method I adapted over to Blender from Max originally.
If you grab the spine rig I posted by the root at the bottom and turn it horizontally you will find it makes a quadruped spine control set up exactly as you are describing.

Due to dependency graph issues Blender also normally requires two armature objects to be used with spline IK. A deformer bone chain and a controller bone chain. It’s the controller chain you would apply shapes to as they will be your controllers.

Anyway hope this helps.

I hope I understand your question properly. In its unmodified state the spine, an IK chain, flexes upward when the spine length is shortened. This positive arch is a common feature in cat motion. To achieve a negative arch (downward curvature), the bones of the IK chain need to be tweaked with small rotations on X that put the spine in a state that allows for negative curvature:


A typical cat stretch kind of pose, head up, shoulders low, forepaws outstretched (and digging into your carpet no doubt), spine arched negatively, ass in the air, hind legs extended back and rear paws on tiptoe. It’s not the only way to do this kind of thing, just the way I used in this rig.

Hi, Looks like maya nurbs ribbon setup which can be very helpful. Can you please explain it more. It feels like some steps are missing. Breakdown in seperate chains will be very helpful (If you have some time ) :slight_smile: