How to avoid sliding?

how to avoid sliding when doing walk animation?

Hi! Could you provide more informations about your animation & rig, like are you using IK or FK legs, is it a looped cycle, is it in place or developped, …? Maybe show us your animation.

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I use a simple rig like from mixamo but with a root bone.
Im using walk cycle animations and I dont want to change my rig bc I need it for motion captures.
Is there a trick with the time or an addon or a tutorial for blender?

Well I’m afraid you can’t do much. At least not easily & quickly.

Avoiding foot sliding on a walk cycle is usually a matter of adjusting the forward translation curves of the foot’s IK controllers. For that, you usually use an animation layer in which you add just the forward movement to the rig’s placement controller - which turns your static walk cycle into a developed walk cycle. Then, add a plane as ground with a pattern texture, so you can easily spot any foot sliding.
Once that is done, you can adjust the foot IKs. Then turn off the animation layer which adds the forward movement.

You have some issues:

  1. Mixamo animations are fully bake, meaning you have a keyframe on every bone for every frame, which makes any change somewhat difficult. You’ll have to rely on using animation layers in order to counter animate without being forced to deal with each keyframe manually.
  2. You only have a “deform rig” from Mixamo, not a thing you’re supposed to animate directly (unless for some simple tweak like a rotation in an IK chain). So you will probably have to build a controller rig that will provide you the IK chains without changing Mixamo’s rig.
  3. Mixamo has a very variable quality delivery. Some animations may be perfectly clean, some may be jiggered like an old person. If your foot is sliding only because it’s not the right speed, it will be a matter of adding a couple keyframes in a layer. If it’s moving back and forth, you’ll have a bad time.

So… Now comes the crucial question: is it worth it?

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As I said, Im using the simple rig for motion captures, not for mixamo. So yes its worth it.

Huh yes I misread that. Though I suppose the issues remain.

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Hi, I found this tip about animation speed and length of curve quite useful.

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I think that some sliding problems could be fixed algorithmically. Unfortunately, it would require some temporal awareness that Blender lacks. Would require (multiple) bake action steps. You need to bake feet position relative to whichever is on the ground, so that you can cancel out root position relative to the grounded foot, whichever foot that is.

Part of the issue is that there are multiple ways to handle matching the length of a stride to a particular path. Do you want to alter the stride length, or do you want to alter the cadence? Either of these are going to have effects on the rest of the animation-- your shoulders move differently when you take baby steps vs. giant strides. Those kind of effects can’t really be determined algorithmically. Not in a simple way, at least.

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