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The issue here is the descending animations from Mixamo.
(You will need an Adobe login to download the animation.)

enter image description here

The floor doesn't move as the legs are moving down, I have to manually fix every keyframe.

The issue is also reported on the Adobe site.

Currently there isn't a fix for such an issue, but I am wondering any of the following.

  • Is there a workaround you found with the mixamo descending issue?
    An easy way to fix it without keyframing each step.

  • Is there an alternative method to generate a quick walk animation down stairs?

see attached Blend File here on Pasteall https://pasteall.org/blend/183f43dc099a45ec8cc8ea78ccacbdf7

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    $\begingroup$ Hello, hard to tell without any screenshots, file, etc, I've made a tutorial in french about what sounds like a similar problem, maybe take a look and tell if it seems to answer: youtu.be/kVCTgDZFSEk $\endgroup$
    – moonboots
    Jan 6, 2022 at 8:31
  • $\begingroup$ hi @moonboots It looks like vklidu was kind enough to edit my post with a screenshot and image. I have also uploaded a Blend file to Pasteall with the descending stair animation seen here. mixamo.com/#/?page=1&query=descending I think the issue is similar but with the descending stair animation it seems that all the objects are hitting the floor. I will admit that your video seems to tackle correcting a looping stair animation from Mixamo but not exactly sure if its the same issue. $\endgroup$
    – Arif
    Jan 6, 2022 at 16:45
  • $\begingroup$ ok, doesn't seem to be the same problem, I'm not sure there's an easy way to fix it, it looks as if some keyframes are missing actually? $\endgroup$
    – moonboots
    Jan 6, 2022 at 17:07
  • $\begingroup$ Probably better to use another BVH resources ... like here is free set of Carnegies Mocap data files (includes AVI file for motion preview) ... converted version to BVH is here ... up and down stair is under 114_09 file ... $\endgroup$
    – vklidu
    Jan 6, 2022 at 17:11
  • $\begingroup$ hey @vklidu That is a great resource. I will need to go through the website and start cataloging each Mocap. I looked through a few tutorials on how to import BVH and it looks relatively easy with some minor rigging. Some youtube videos I watched to understand the process. youtube.com/watch?v=Ux959so49Xk Then it got me thinking if there are other easier workflows and I found this add on. blendermarket.com/products/Pupa Not sure if the addon is any good, will need to investigate. thanks for the help. $\endgroup$
    – Arif
    Jan 6, 2022 at 21:07

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Mixamo's source data definitely doesn't follow same conventions, bone structure, naming, rig etc ... it generates issues ... here it looks like the data was automatically processed to keep feet contact with a floor without care of specific kind of motion.

Motion is baked into bone rotations keyframes per frame, that make it quite difficult even for just 30 frames.

Luckily for you Adobe released a Control-Rig addon that make this fix quite simple, because addon generates also IK controllers, that let you animate a leg almost by one bone.

In your specific situation you would have to fix only Z axis of this controller by just 2 or 3 keyframes.

One of the well knows issue is wrong interpretation of bone orientation. Import FBX addon has a feature Automatic Bone Orientation, but it will mess Mixamo's addon as well. Instead ... upload your character (or download from Mixamo and re-upload "as your model") to let Mixamo run through its auto-rig process, assign motion and download as FBX. Import FBX (without any changes in import properties) into Blender.

Download, install, enable addon ...
and if all worked as supposed to, just press Create Control Rig in 3Dview > Mixamo side (N) panel.

enter image description here

Now when feet use IK rig, all you need to do is correct damaged Z information.

Right Feet (fix from frame 5) enter image description here

Left Feet (fix from frame 17) enter image description here

For the left foot you would have to fix also Foot Rotation ... enter image description here (copy first keyframes and move them on X axis to frame 30 and one more keyframe to replicate motion from frames 1-15 ... or just delete 16-30, duplicate 1-15 and Mirror on X axis)

enter image description here

Note: I used a screenshot of sideview (3) on frame 1 to get a pose reference and drag&droped into viewport to match on frame 30 (not 29). Since all bones are OK up to Hip bone you can nicely see if you match a loop animation.

For more informations about addon or usage of Mixamo data in Blender check this video.

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  • $\begingroup$ Ahh Thank you. Going to check out the add on and try the fixes you recommended today. $\endgroup$
    – Arif
    Jan 10, 2022 at 19:12
  • $\begingroup$ Would you have to have the blend file you worked with? $\endgroup$
    – Arif
    Jan 10, 2022 at 21:39
  • $\begingroup$ Scratch that I got it to work. Thanks. $\endgroup$
    – Arif
    Jan 11, 2022 at 2:06
  • $\begingroup$ Thanks for your reply. I ran into this same issue. Could you post a link to the corrected file? $\endgroup$
    – Геннадий Горбач
    May 8, 2022 at 6:23
  • $\begingroup$ There was some issue to upload 3.x blend files ... here it is. $\endgroup$
    – vklidu
    May 10, 2022 at 17:08

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