Hello everyone,

I'm writting to know if someone has encountered the same issue and if, hopefully, there is a solution. I own a PN3 neuron mocap suit. Everytime I record an animation, it does amazing in iclone, except for the left shoulder. I imported the motion file in Blender to see if the issue came from the suit or Axis software, everything was working fine. When I modify the motion in iclone, everytime I break the motion or smooth keyframes out, the left shoulder becomes shaky as hell. I've tried to optimize per part, per frame, smooth out in the curve editor, optimize key frames, it's always jittery, even when there are only 2 keyframes left on the animation section. Only solution I found is removing the left arm motion, but I wish I didn't come into this, it looses so many more data. Here there is an example. It's subtle, always last a few frames, but everytime I try to correct it, it's worse. Sometimes it happens with the right arm too.

Thank you in advance for any help !

kalex

Hi there,

I own different Perception Neuron Suits as well. In order to may help you out, I would need some more footage and maybe record the way you try to fix it.
On my end, almost everything works well.

Edit:
What you could do as well, is providing the raw animation file.

Regards

Hey Labrats,

Thank you for your quick answer and help.
Here you can find more jitters:
https://www.youtube.com/watch?v=nt7kmj8H66Y
https://www.youtube.com/watch?v=XdexE4lHF5g
https://www.youtube.com/watch?v=8ljBtyk0IMc

The thing is those jitters aren't there in the raw file, they occur when I'm modifying, correcting or breaking the original animation, and I can't understand why. Initially, I wanted to smooth and correct weird foot and leg movements. Succeeded in that, but now the new motion has arm jitters :crying:

Unfortunately I can't tell from this footage. You will have to Screen-Record Iclone the way you are approaching to alter the animation or provide a Link for me to download the raw / the modified Animation.

Regards
Labrats

Okay I'm sending here the raw motion (fbx), and corrected motion (imotion). It's a rather long animation (approx 5 minutes) so I don't want to waste your time... just so you can see the difference between original and modified you can go to frame 13536, there is pretty obvious and unexplainable jittering on the left shoulder.
Also you'll notice in the beginning the legs are a bit shaky when changing position. I solved that but I wanted to know from your expertise: what would be the best way to prevent foot sliding or leg shaking when walking with PN3 ?

Thank you so much for your help and guidance !

Kalex

Motions:

https://drive.google.com/drive/folders/1wfCA0VdKnpsMIrh4y-c4ZPIZnaw2iLR0?usp=sharing

So, I looked at your animations and couldn't reproduce the jitter error.

Maybe it's the way the animations are edited. If possible, a new layer (see picture) should always be used and the "Base Motion" should never be changed (only to eliminate errors).


Maybe the footsliding comes from saving the animations? In the preferences, "compress motion on save" should not be selected if you want to edit animations. otherwise slide errors will occur and details will be lost (this can be seen in the attachment in the project).


I (I think) removed the jittering from the edited animation using Curve Editor (smooting  Clavlicle L about 2-3).

If this animation is needed without foot sliding and you don't want to edit everything from new ones, you could use "copy pose" from your already edited animation (I would deselect the legs).

I had partially changed the raw animation for the test to see whether the jitter errors would appear, which was not the case.

Jittering can also happen if the animation's FPS doesn't match the timeline, as Iclone then tries to squeeze/stretch it into that.



Unfortunately, footsliding is an ever-present enemy in low budget mocap. I fix it with Foot Reach/Release in Iclone (Iclone's "Motion Correction" auto tool usually doesn't work as well as it was advertised). When I'm satisfied with the Motion. I use "flatten all motion with constraint", which creates (and overwrites) a Motion Clip with all reach, constraints and motion data merged/baked into one.

This however, can not be undone and all keyframes are flattened.

I saved the Project, in case you want to "research" it:
https://drive.google.com/drive/folders/1mz4YLhu6C6HXba7QLR7iWj24f-B97x6S

Hope this could be of some help?

If you still have any more questions, please feel free to write me.

Hey Labrats,

A big thank you for your time and the detailed answer (and the file !!) you provided. I appreciate it very much. I already did some of the things you mentionned, though I didn't think of adding a corrective layer. This would be a huge change already. Thank you for pointing that out.

Regarding the foot sliding, honestly I don't have that much with PN3 at the moment (touching wood), it's more legs that can be shaggy at some point. What I saw is with a strong and even natural lighting the suit will react nicely, having to calibrate every 2 to 5 minutes. I was wondering if you would have some tips too ?

Thank you again for everything !!

Kalex

Hey Labrats,

So I made sure to follow the steps you mentionned. I was really happy when I finally corrected the shoulder jitter (you were right, smoothing the clavicle by 3 seems to solve it, I was smoothing the shoulder). But I notice that when I save the motion file to motionplus, the jitter comes back. Is it because every keyframe is automatically flattened to the motion file ? When I sample the animation, there is no jittering though...

First of all, sorry for replying that late.

Regarding the jittering when saving the motion to motionplus:
I can't really tell what causes this. I do not save my motions as motionplus files. If you disabled compressing motions on save in your preferences, it shouldn't be happening (at least when you save them as standard motion files). Maybe Reallusion should inspect this issue.

If it comes to Perception Neurons Motion Capture, I don't have 3.0 in particular but 2.0 and Studio.

But feet and leg issues happens even on the studio version.
To reduce or even eliminate it in some cases you should do the following:

- measure your body proportions accurately (especially hip to knee - to feet) and change Axis Software settings accordingly

- Proper placement of your "neurons" is crucial. Make sure the stay at their place the best way possible

- Change constraint and smoothing settings inside Axis Software until the results show the best results (depending on your type of motion, it needs to be changed)

- I do export them via FBX and not per Livelink to Iclone (didn't had timecode at first till Nov 16 2023). Don't know if this info is of any use to you

And if your already recorded motions have still issues, I do the following to fix it inside Iclone 8 Curve Editor:

Change the filter in the drop down to Z Axis Transform only and unthick the rest.

Then smooth all of them by 5 to 20.
It may happen, that the knees start to have stretch / limit issues after the smoothing process, because the altered Z positions.
To correct that, I open a new layer and bring the feet slightly up (Z Axis).

These methods are in some cases deconstructive and professional animators wouldn't do it that way. But for me it works like a charm and is much faster then any other methods I know of.

Hope I could be of any help on your 3D journey

If you got more questions, feel free to write me. It may take some time to get a respond though.


Oh, and if you are interested, I will post our newest movie later this day in this Forum as well. If desired check it out :)

Regards
Labrats

Hey Labrats,

Just noticed you answered me, thank you so much for such detailed answer and advices. I will reply with more detail tomorrow (getting pretty late here) but wanted to say thank you.

And of course I'm very interested and curious about your upcoming movie. I'm working myself on some superman fanmade movie so yea I am all ears when it comes to other projects =)