Universal Sonic Mouth - Blender Rigging Tutorial

This is a Blender Tutorial on how to create a Universal Sonic Mouth. Universal meaning the mouth can move from the left to the right of Sonic’s muzzle, without the need of separate meshes or rigs like the games use. This method is usable in any other 3d program that has a shrinkwrap-like feature.

expression tests by Deadlyname15


Marza Studio’s “Universal Sonic Mouth” used in the CGI of Sonic '06 which inspired this. English

translation from PsifinityDXI

Free Demo File Download
Short Video Tutorial:

Animation Demo:
Lip Smoothness (Old- sharp “shrinkwrap” vertex group; New- smooth “shrinkwrap” vertex group)

Final Note:
I made this tutorial back in 2021, with the help of PsifinityDXI, and there’s been a struggle to find a permanent place for it since. After sticking around here for awhile, I think this community is a nice spot. This kind of idea could be used for more than just Sonic, I’ve already made some headway using it on Kirby. Hopefully you guys can find some use for it too :moyai:


This is incredible concepts and tutorial for 3D Cartoon Mouth Rigging in Blender! and also extremely valuable in certain Cartoon, 2D to 3D style adaptations! Congrats for making this real and available!

I’ve just finished a double-session Live Stream which, where I make an attempt to reproduce the main concepts of that Mouth Rigging method, applying ot to an OC of mine, while trying to cover a variety of things that may be more complex to understand, especially to people who might be newer to Rigging in Blender. I believe was successful for the most part, but some retakes certainly should be done because of the CD. It wasn’t difficult, because priorly, I was making tons of crazy Mouth Rigging experimentation on another character, occasionally borrowing many game-changer concepts from your Universal Sonic Mouth Rig tutorial.

I know it’s a bit chaotic, too long and not much. But I want to tell you I am certainly one person who found some amazing use for your ingenious and dedicated solution! I think more people should be talking about this method at this point.

I’m still struggling to make my own Mouth Rig for a specific stylistic 2D to 3D Character adaptation (which curiously has some influence from Sonic CD anyways: the ‘Muzzle’ shape on the Lower Face Region), and then probably make a tutorial for it when/if I succeed. But your tutorial was so far the most impressive combination of techniques I’ve ever seen for this characterization matter.

I’d point out some of the most valuable and curious concepts for 3D Cartoon on that method, or derived from my analysis and further experimentation:
:bone:Mouth Interior features (Arcades/Theeth, Tongue, etc…) are automated in following the Mouth Position which slides over the Muzzle “Ghost” Mesh;
:bone:Shrinkwrapping Muzzle “Ghost” Mesh Deforms simultaneously and similarly with the real Mouth/Lower Face Mesh; which is really interesting concept. Interestingly for the double Shrinkwrap Modifiers, I found out another (perhaps additional approach): they can actually be used as ‘Box Volume’, with inverted combined Offsets for Outside and Inside for Snap Modes (e.g., Outside -0.02, Inside -1.2; what’s in-between the invisible Offsetting Surfaces doesn’t actually Shrinkwrap Mesh: only when the Mesh is pushed or pulled into the inner or outer invisible Surface ‘walls’);
:bone:Regular Deform Bones on LBS (Linear Blend Skinning), or Dual Quaternion Skinning), seems to beat Spline Skinning in so many ways on the approach of Rigging the Deforming shapes of the Lips so to correspond to 2D looking widely expressive Mouth Shapes, not only regarding the ‘Mouth Contour’ along the curves surface of the whole Muzzle Region, but apparently, it retains good Deforms Volume of the Lips when these have to protrude, retract, etc. (provide no big Rotations of course).

I’m probably forgetting other aspects. Thanks a lot for making and sharing all those inspiring Advanced Rig stuff, and help uncoverning the mysteries of 3D Cartoon Rigging in Blender.

Best Regards,

PS: Of course, I’m not asking anyone to watch those 2 Live Stream videos entirely. :joy_cat: It’s just to present that this exists now.

1 Like

Wow. I really appreciate the feedback.

Despite the project being like 2 years old at this point, a few other artists and I are continuously look for ways to improve or further the set-up. (I may update this soon with some recent stuff we’ve found.) We can definitely look into the stuff you’ve suggested though. In any case, this is a very welcome development.

We discuss all the time about having an in-depth video about the tutorial and, from what I’ve seen, this seems to be perfect. I think many people will find this useful as well. I’ll be sure to forward it when I can :))

1 Like

This is really great to know! Considering the complexity of Organic Rigging, besides the problematics of stylistic adaptations in general. I’d love to see that new version of the Universal Sonic Mouth Rig, certainly there’d be interesting changes or implementations.
You can count on me for further experimental achievements on this project.

I’d like to have at this moment adequate demonstrations, of the various stuff I’ve been tweaking in 3D Cartoony Mouth Rigging, in relation to Universal Sonic Mouth Rig, on the specific case of the Character Design I’m working with, but I’m still in the last stages of the creative process. But as soon as I get it achieved, I’ll record some clips.

I’ll resume though some aspects:

:bone:I’ve recently found out, through plenty of Rigging tests, that the way the Universal Sonic Mouth Rig has its Lips’ Geometry made in Rest Position for the Mesh (extremely regular Mesh, especially if we consider the nearly identical 2 parallel Face Loops of the Lips that exist in-between the Mouth Hole Region and the Mouth Contour Region), seems to have enormous impact in the correct Deforms while trying to shape the Mouth in different expressions (a condition that we are able to assess, partially but well enough, even before Shrinkwrapping features in some sense). On my last post, I’ve compared Skinning methods results for this Lips Deforms matter… but turns out I was probably mistaken: there is actually a great chance it was much more a Mesh Geometry+Topology problematic. Thus, I think I cannot stress enough the importance of highlighting the Mouth/Lips Mesh condition for the kind of Mouth Expressions these kinds of 3D Cartoony Rigs require. (Of course, now that I’ve adapted the Lips Mesh of my Character, and was successful with Linear Blend Skinning, I will test it also with Spline Skinning). In other words… this is a colossal, and not actually evident, Mesh concept, that you got it right, for Universal Sonic Mouth Rig; I believe it is yet another pillar for stylistic adaptation; allow me to state it should be a bit more emphasized in the tutorial.

:bone:I’ve been tweaking the Control Rig for Upper & Lower Arcades (which include Theeths and Tongue) in relation to the “Mouth Position”. My intuition says this might have been one of the developments you’ve been making to a version 2.0. But anyways I’m verious curious to see what would be new when available.

:bone:Stylistically speaking, for a Mouth/Lips that might a bit more organic than usual Sonic’s Character Designs, I’m researching ultimately different solutions on how to get the Lips/Mouth have (or develop) slightly more organic Volume shapes, as they get Deformed along the Muzzle/Lower Face. I have already a crazy proposition that works (‘Lips Profiles Bendy Bone Splines’), with Armature Deform, but it’s a bit overly complicated to set up and mantain, so I’m trying to simplify. I believe Shapes Keys would work (it might be just a better to have them to reshape, Morph the Lips Mesh on the “Y Axis”, or more precisely, the “YZ” Plane corresponding to a profile, sideview); but I’m looking also for simplified Armature Deform possibilities. This is particularly hard, but interesting problematic, because (at least on my experience; which is actually relatively small regarding Mouth Rigging), as soon as we try to make more complex Mesh Geometry & Topology for the Lips like from the start, we seem to immediately loose the qualified simplicity for the regular Deforms for the more 2D ‘planar’ expressions of the Mouth/Lips along the Muzzle/Lower Face, furthermore the Lips Volume also tend to accumulate horrid distortions as well!! So, I believe a strategy would be something like: ‘building up’ the more organic/complex ZY ‘Profile/Volume’ Deforms/Morphs of the Lips, after their basic Deforms.
This is just an experimental sample: at some point from this video’s timestamp (click the link plz, not the thumbnail to make sure it get to correct timestamp), I present that Lips Profile BB Splines Armature Deform alternative, which is a bit overwhelming in my opinion but it works; I should make a tutorial for that in the near future, because this starts to relate to the complicated “Profile Curves” concept from a Pixar Youtube video; which probably relates to also complicated “Cage” Rig. Interestingly, the ‘Lips Profiles BB Splines’ can be used for Lips Rig in combination with Universal Sonic Mouth Rig. But at that moment of that video, note that I didn’t really understood the Deforms quality property of the simplified Mesh Geometry/Topology for the Lips Universal Sonic Mouth Rig used, so I was getting way more realistic 3D Cartoony Lips than I was looking for, beside the fact it was very hard to maintain good Lips shapes without, apparently, Advanced Rigging technique.
correctly timestamped video link

And here below in a screenshot, is the same character with a simple Mouth Pose, however, with the Lips Mesh changed to the pattern of Universal Sonic Mouth Rig!! And now the “2D” Deforms work incredibly well suddenly. These Lips, when Posed, Deform in a much more regular fashion, ressembling the 2D Cartoon styles, and matching the achievements of your Rig method. But now, the stylistic quest in my particular case is that I need to consider how to work on the Lips in a way to give it slightly more organic/anatomic shapes on whichever Pose, but at the same time, preserve the spontaneously ‘structural’, regular quality of their Deforms, from their original, regular, planified Geometry on Rest Position – spontaneously ‘structural’ Deforms quality, that I wasn’t able to get from any other Lips Geometry so far. It is likely words will hardly will express the problematics very well; but, at least I tried. :joy_cat: In my perception, the extreme expression tests by Deadlyname15, that you shared in the beginning, represent the aeshetical middle term, between what I’m trying to achieve for the Lips, and the original Universal Sonic Rig, which can be considered more like the foundational basis forms. I still wonder if any other Lips Geometry would have similar potential for such kind of cartoony expressions. :thinking: This remains one of the biggest Mouth Rigging interrogations for me. But I’m very glad that the basis form, that is present in your Universal Sonic Mouth Rig, can do what they do, on any other different character; it’s just fascinating.
Captura de tela 2023-09-22 192518

Thanks! I wish I had made this a better series, but it was more like a ‘first run’ thing, like in games streaming; at that moment, I was already helping another artist, who was very intrigued by the method just as myself, but hadn’t just yet enough know-how of Rigging in Blender to get through the tutorial. If it can still help out more people trying to understand, reproduce, or learn from, the Universal Sonic Mouth Rig method in some way, this would be even better.

Also, thank you for the reply;
I think overall, these Rigging techniques for 3D Cartoon adaptations from 2D are incredibly valuable content for the community; and it can be difficult to believe sometimes it can even get better and better overtime!:scream_cat:

PS: I’ve made up my mind about Shape Keys, after the latest tests for the Lips solution: Shape Keys in this particular problematic adapt very well, by dribbling critical complications of the Skinning Algorithm(s) on the Lips Deforms, from the Rest Position of the Mesh Geometry; meaning it is actually much easier to just keep the analytic, simple and regular Mesh Geometry pattern of the Sonic Lips, and get subtle Morphs (Shape Keys) as required; and they will also adapt “Locally” to the Mesh according to the Lips Posing on the Face; of course, for this to work well, it requires that the Mouth Expressions are working well already —my original intention would be to not require Corrective Shape Keys at all if possible, just plain Shape Keys to reshape the stylistic, organic Volume of the Lips whenever required; I believe this is feasible on different Character Designs). All the Armature Deform solutions I could conceive for this Lips case, In comparison to Shape Keys, seemed far more complicated and unreliable; besides, they would need additional Mesh Geometry (possibly! built on top the regular Sonic Lips Mesh? with unknown consequences), as well as more Bones, Weight Paint, Parenting systems and/or Bone Constraints… also making the interface between the Lips and the surrounding of the Mouth far more difficult to solve. Here is a Mouth Expression sample with Shape Keys (the Lips Mesh Geometry and the Lips Rest Position, is equivalent to Universal Sonic Mouth Rig; although sketchy, the results are actually very satisfying and starting to match the 2D Character Design :scream_cat: I just can’t thank you enough for showing artists probably one of the best paths possible inside Blender for such kind of 3D Cartoon Character styles :heart: You are a God!):

1 Like

Thanks for the compliments.

I definitely view this tutorial more as a foundational technique than a complete thing. Depending on the character you use and the details you want, your implementation will vary.

One of the people that I’ve been working with, @DANCADA, has made improvements and findings of their own to this rig method. So far, they’ve implemented the teeth and tongue following the upper mouth and lower jaw position that you mentioned AND have a more detailed mouth topology that allows for wrinkling with the use of shape keys:

They’re thinking about making their own breakdown of this at some point, but in any case, it’s implemented well in their latest rig here.

1 Like

This parallel Sonic Rig project should probably add good stuff to the foundational inputs; I haven’t checked in details yet, only the big picture of the video and presentation, but will certainly be great idea to learn from it as well. Thanks for sharing!

I believe you were mostly successful at this foundational objetive. Naturally, at this point towards the future, an Universal Sonic Mouth Rig “2.0” would be even greater. But I know how much dedication it takes to make, at the same time, complex and good tutorials.

Currently, the last stage of my experimental Mouth Rigging, is trying to combine (in a non-conflicting way!) multiple Shrinkwrapping features on that generic Lower Face Region; such features could be through Shrinkwrap Modifier and/or Shrinkwrap Bone Constraints. I conceive there are different purposes, involving the Shrinkwrapping functionality, for Mouth Rigging; but for these kind of 3D Cartoon styles with stylized ‘Muzzle’ or requiring highly exaggerated and stylized Mouth shapes, I think the highest priority Shrinkwrapping functionality or purpose is indeed the Mouth Mesh sliding seamlessly anywhere onto the Muzzle, that you have made. But even the original Universal Sonic Mouth Rig tutorial, has at least 2 additional Shrinkwrapping functionalities in it in additional to that main one. They would be: the Shrinkwrap Bone Constraint on ‘Mouth-Position’ Bone functionality, and, a bit more abstract, the Double Alternating Shrinkwrap-Sudivision Surface Modifiers Combo functionality. These particular Shrinkwrapping features, if properly set up, seem to hold no conflict between themselves and the main Shrinkwrapping feature; but it’s actually very easy to get failing Shrinkwrapping features, by adding extra Shrinkwrapping functionalities —as I’ve been testing out many different approaches. So, I’m still trying to see which features would be combinable, how and why. I have a couple of interesting examples (of things that can go wrong!), but that would make an even longer post, so, unless you’d be interested in the details I’d post in text. In principle, I would be glad to present them, though if I make video demonstrations at some point this would be the ideal situation. It is likely that you’d be aware of many of the plausible problematics already though.

When I get a good look at that new Sonic project, I’ll post a feedback also.
Thanks for the conversation. Cya!

I’ll be glad to hear feedback and thoughts whatever you find.
I only ask that you just try and keep it concise. No offense to you, but your last reply was quite the read. If there’s any way you can condense your findings to the key points, that’d be appreciated. Really, I’m only interested in what does/doesn’t work and a quick explanation of why.

1 Like

I understand the importance of being concise; I’m working on it. Don’t worry, it’s a valid remark. I would explain the reasons behind my pattern, but that too would take a large paragraph of its own. :joy_cat:

For the couple of problematic Shrinkwrapping cases I’ve identified, I’ll re-write them down in a simplified way as soon as a I can, likely on the following days. Ideally, I’d like to add video clips to completement the cases; but this approach shall be for the future.

1 Like

Now this should prove useful…

1 Like

Hey, @KamauKianjahe;

Sorry about the delay. Here a couple of interesting cases of inadequate Shrinkwrapping interactions:

  1. In Face Rig, the exist a somehwat conventional technique of giving a Shrinkwrap Bone Constraint to Bones in the Control/Deform Rig. For a Mouth Rig, it would Target the Muzzle Ghost Mesh Object; but in the Universal Sonic Mouth Rig, such feature cannot be implemented freely/arbitrarily wihout major risk of Dependency Cycle.
    This is because the Muzzle Ghost Mesh is dynamic (not static); so, in no way apparently should the Muzzle Ghost Mesh contain Vertex Groups from Deform Bones which are Owner of Shrinkwrap Bone Constraint Targeting the same Mesh (Muzzle Ghost Mesh) that they Deform; nor can such Deform Bones be indirectly affected by Shrinkwrap Bone Constraints that would be, instead, on their respective Control Bones. As soon as we Disable/Delete such problematic Vertex Groups in the Muzzle Ghost Mesh, or the Shrinkwrap Bone Constraints themselves, the Dependency Cycles cease.

A) Not using Shrinkwrap Bone Constraints for that extra feature.
B) Maybe, as a starting valid condition, would be having a Rig, in which the Deform Bones which Deform the Mouth Mesh are totally distinct from the ones which Deform the Muzzle Ghost Mesh --even though their Weights would remain ‘equivalent’, each single Deform Bone wouldn’t be affecting both Armature Modifiers simultaenous, just one of them. This would mean more Bones, but less ‘stacking functionalities’. Then, hypothetically, the Mouth Mesh Bones that Shrinkwrap, they wouldn’t be attempting to ‘Re-Deform’ the Muzzle Ghost Mesh as they Shrinkwrap, since they would only be responsible for Deforming the Mouth Mesh (which already has got Shrinkwrap Modifier(s)).
C) Other

  1. I finally understood why my Outside+Inside Shrinkwrap Modifiers combo (the invisible ‘Box Volume’ feature) stopped working, as soon as I’ve implemented a main feature of the Universal Sonic Mouth Rig: the simulatenous Deforms, through Armature Modifiers, for both Mouth and Muzzle Ghost Meshes.
    What happens is that, originally, the Muzzle Ghost Mesh I was using was static. In this sense, by having the Mouth Mesh with that ‘Box Volume’ Shrinkwrap Modifiers’ combo (Targeting the static Muzzle Ghost Mesh of course), the Mouth Mesh, for example, in the case of Posing an exaggeratedly protruding Cheekbone, would eventually ‘touch’ an invisible maximum threshold, and the Cheekbone couldn’t protude any further despite Posing its Deform Bone further away, maintaining a good extreme shape --I know this is restrictive, but it can be cool too.
    However, as soon as I gave an Armature Modifier to the Muzzle Ghost Mesh, and that the Mouth Mesh started to Deform in synchrony with it, then, the ‘Box Volume’ feature also became dynamic --meaning, its invisible surfaces: mininum & maximum thresholds, were also turned into dynamic elements! And this was the behavior I wasn’t expecting. So, as the Mouth Mesh Deformed, it could not really approach nor ‘touch’ anymore such original thresholds, because they were also ‘moving’ away (retracting or protruding accordingly: in synch!), as they immediately depended on the udpating, Deforming Muzzle Ghost Mesh. The result was that the Cheekbone could be Posed mostly freely, without hitting any restrictive, insivible surface (inwards or outwards), as if no threshold existed at all.
    The combination of the systems didn’t break the Rig nor created Dependency Cycle apparently, but the original ‘Box Volume’ feature was just being neutralized --literally-- by the new dynamics.

A) So far I just conceived one thing that might work, in order to de-neutralize the extra feature. A 3º Mesh Object; which would be structurally more ‘basal’ than the Muzzle Ghost Mesh itself: sort of “Static Muzzle Ghost Mesh”, to which the Dynamic Muzzle Ghost Mesh would be Shrinkwrapped to. The Static one would set the inner and outer generic limits (‘Box Volume’) for the Dynamic one; and the Muzzle Mesh would continue doing what it does, but now there are thresholds for them. Note: if this works, it could also serve as ann alternative to Shrinkwrap Bone Constraints to the Control/Deform Rig, since the Mesh itself would have inner & outer limits.
B) Other

Well, as much as I tried, I couldn’t reduce the post more than this state. I hope at least it’s easier to read this time.
But next step, I want to make some videos to reproduce these events.

1 Like

The freely deforming cheeks is a useful find.
In regards to the “dependency cycle”, I will say the shrinkwrapped bone is designed to follow the muzzles every move. It should be dependent otherwise the lips fall if muzzle if you deform the muzzle too much. For your purposes of freely deforming the cheeks, i could see how it proves troublesome though. It may require a new solution or just manual posing

1 Like

Those two Snap Modes (Outside or Inside), that exist in features such as Shrinkwrap Bone Constraint/Modifier (and also Limit Distance Bone Constraint), can serve multiple, very interesting uses --even when used individually, instead of a Outside/Inside combo. For example, only using Outside may be useful for Mouth Rig, for Lips Bones in certain setups I found. It might be compared to an ‘inner Collision system’.

I think I understand what you mean: you were referring to the Mouth Position Deform Bone in the original Universal Sonic Mouth Rig, which is the only one that has got a Shrinkwrap Bone Constraint; and that particular Shrinkwrap Bone Constraint works, because, also, the Vertex Group of that Deform Bone doesn’t have Influence on the Muzzle Ghost Mesh, only on the Mouth Mesh (just like the case of Lips Deform Bones).

For the Lower Face (Cheeks, Cheekbones, etc.), I’ll have to make those proofs of concept. It’s one of the last interesting challenges to investigate at this point for my character.

When I get those tests, I’ll try to bring up some conclusive clips.
The idea of course is continue to explore valid alternatives for those Custom, Cartoony Facial Rigs.
Thanks again; Cya around!

I don’t understand the third step. No changes :((