How to convert animation from Mixamo to Blender to MikuMikuDance?

I am trying to convert animation from Mixamo to MikuMikuDance (MMD).

First, I converted the Mixamo’s rigs to Blender fbx using this Mixamo converter

Then I stuck here.

Is there any tool to convert? I have looked into an addon to retarget but since MMD rig system is different from Blender’s, anyway I have tried but the rigs have been distorted when animating.

Help please. Thank you.

Look at https://github.com/powroupi/blender_mmd_tools , which can export .vmd files from animated armatures.

If your goal is to export animation that can be used by “standard” MMD models, then it would be wise to import an MMD model (using mmd tools again), give its bones copy transform/copy rotation constraints targeting another, Mixamo-animated armature, bake the animation to visuals, and then export the motion.

Depending on your setup, it may be possible to just export the Mixamo animation directly, but it would require a bit of experimentation for me to tell you exactly what you should do, you’d end up with animation on bones with non-standard names, and you might end up losing some characteristics if it depended on any constraints.

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Thank you.

The goal is just for using any downloaded animation from mixamo to any MMD model/rig. That will make things and jobs to be easy to handle in the future.

I have been using MMD tools for years but this time it cannot do the thing because the rig system of Mixamo and MMD is different. It can export the file but not the motion.

I will test your suggestion.

I haven’t used Mixamo. It’s hard for me to imagine how the rigs could be too different to be exportable onto any arbitrary MMD model. If you feel like linking a .blend file with an animated Mixamo armature in it, I might be able to tell you more.

This is the .blend file in which I converted mixamo rig into blender rig.
untitled.blend (288.9 KB)

This is the fbx file downloaded from Mixamo
Fast Run.fbx (238.1 KB)

This is the converted fbx file (to Blender, not MMD)
Fast Run.fbx (369.7 KB)

There’s not really anything special about that rig:

You have armature-level transformations in that file, which won’t get exported and maybe will screw things up. First thing I did was to clear rotation, scale, location on the armature object and delete all keyframes for those.

Then, I used “create model” from sidebar/MMD and joined your armature to the new MMD armature. I made a few cubes so I could see that it was working and exported the model, then exported the animation. Looks like it’s working fine.

That leaves you with an extra bone-- the one generated by MMD Tool’s new model-- but you can delete it if you want. It’s not really doing anything.

If you want the armature level transforms (well, the translation and the rotation) in MMD, you’ll need those to be on a bone rather than an object. I’m not sure the best way to do it-- best would be to directly copy your armature transforms onto your root bone. There are plenty of ways to do it with baking animations, but it seems like you should just be able to copy/paste keyframes-- I just don’t know how to do it, in the case of copy/pasting from armature->bone.

Note that MMD doesn’t support bone scaling (or object-level scaling at all, not outside of .x files, and even then only uniform scale) and so no animation using scale is going to work in MMD.

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thank you very much