Hello,

I would like to understand a problem dealing with hand rotation. My setup is this

4 Ps eye, located like the uploaded image shows.

My test was this one below:

a) I was in T-pose.
b) Keeping that position (the t-pose position), I tried to rotate the hand like that:



As you can see the idea is to keep the shoulder blocked and rotate the arm, in particoular the hand, with an angle of +/- 90°, holding fixed the x axis. I don't want to raise or drop the hand; it must stay in the same position, and rotate.

When I rendered, the program shows me standing in t-pose all the time, without the rotation of my arm. In the render I was simply standing in t-pose
like a stasi animation.
I would like to underline that, except this fact, all my registrations are perfect, no doubt. Simply I can't make mocap follows the right rotation of my hands during the videos . . . and the test I made above is , my tought, the proof of the problem.

Now the question: It is possibile to fix it? And if the answer is yes, how??

Does mocap studio take the hand rotation? Or a rotation like that is too small?

Is my setup too poor? Maybe should I have more cameras or the play station/wi-uu controller in order to achieve that kind of precision?

Sorry for all these questions but this problem makes me mad.

Thank you so much for your help.

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What animation editor is that.. Maya, hard to tell from that image, looks like Maya to me?

Is there a reason you have a twist bone in the upper arm, is this a pre-rigged model, or a model that has to follow that specific skeletal design? Just curious.

iPi needs a Move controller or Wii controller for hand rotations data while recording the action, it is applied as a separate function in the studio after full tracking of the ROI is completed.

Camera set up should work for minimal motions, not going to work for more complex, or extreme actions very well.

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When an arm is straight, it's hard to determine the exact rotation around its axis only by image, because it looks very similar at any angle.
Using PS Move will provide you the exact rotation, but it'll be applied to the hand joint only. That's done on purpose, because many characters have clothing with sleeves, and sleeves usually should not rotate. This is not the same as your sample shows when rotation starts in the joint next to shoulder, but may be still adequate for your purposes.

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You also just can't pick a bone above the hand, even if it had hand rotations applied, and manually freely rotate it without the child bones rotating without pinning the hand in place first.

With the recent updates, iPi has been tracking the whole arm a bit more a accurately, so there doesn't seem to be as much wrist mesh breakage, but there will be some on extreme wrist twists that may need manual tweaking in post.

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Sorry for the delay guys . . .


The Gif with the arm rotation was made in Blender, with keyframes. The model is a simple man and there is a twist bone in the upper arm because helps a lot with the rotation of the entire arm: in this way I spread the deformation all long the arm, not only in the joints; oversimplify: with this rig when I rotate the hand, all the arm follows (the proportion is 0.3-0.4 . . . i.e. if I rotate my hand with a 90° angle- my upper arm will rotate 30-35° ), creating a more realistic rotation, like the gif shows .

This skeleton is particularly useful when you are animating with keyframe beacuse it prevents more frames and balancing animation, used to correct and adjust the position of your model; . The gif was made in order to show the animation I would like to create with the motion capture, that I can't realize right now.



First of all: Thank you so much for your answers! This forum is great ^^. I would like to ask you 2 things:

1) You recommend to use PS Move controller or Wii controller, in order to have better results. What could be the best controller? PS MOVE or WII CONTROLLER? I will buy one of these, and I would like to have the best result.





2) I understand very well the point. You said "but may be still adequate for your purposes". What could be the path in order to achieve this point?

Knowing that I will use the controllers for my hands, can I work directly in Ipisoft or should I use a post production program like Blender to fix this kind of rotation?

When @Snapz tells "may need manual tweaking in post" . . . he is referring to Ipiosft or to another program like Blender Maya and so on?

To be as clear as I can, my final target is this one: create animation for a model holding a sword, fighting with it and so on. When I put the animation in Unity I have to child the sword to the hand of my model. That's why I need an exact rotation of the hand and the arm: because the sword will follow the hand's bone and its rotation too.

Thank you so much for the help!!

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Oh ok, Blender, that helps in knowing that in how the editor performs.

I just asked why twist bone, not that it can't be that way, but that bone will and should never rotate as much as you show, maybe just exaggerated for this post, yes it can help on certain meshes where that part of the arm is broken up by armor, or a specific design of clothing, generally can just be done with the mesh weighting in most cases, but I do see it used a lot more now days.

PS Moves are recommended by iPiSoft, so that's what I use, I have never used a Wii, so can't comment, but Move controllers are pretty accurate when positioning controller and hand is applied correctly after tracking mode, this will take some practice, especially if you don't start your recordings in a T-pose, as I don't.

Yes, even when done right, hand positioning may, and probably will need a bit of tweaking in post, just the nature of it, but shouldn't be drastic.

Blender doesn't use adjustment layers that I know of, it just uses a scene layer type thing, so not handy for animation, so curve editing and timeline key manipulation/deletion/sliding will be needed to get adjustments looking good, but you may have your own ways.

Blenders character re-targeting has a lot to be desired also, the animation from iPi will import great, (although it will import slower than 60 fps, if PS Eyes are used and need to be sped up in Blender, if I remember correctly), and the re-targeting to a character will cause excessive foot skate and other steps will need to be done to counteract it.

You should be able to export a default skeleton right from iPi into Unity 5, and re-target and make adjustments there also, maybe even better, but of course you won't get the twist bones, iPi doesn't have a skeleton default with twist bones, but you should be able to just import and re-target your own skeleton into iPi Studio, re-target it, (can't re-target twist bones though, but iPi will export the skeleton with them), and be able to use it in Unity to make adjustments to the twist bones you show also.

Have you looked on YouTube for tutorials on that? I am not sure if the Unity forum would have answers use with iPi mocap usage, but it may, possibly this tutorial may help: https://www.youtube.com/watch?v=Ux959so49Xk

I don't use Blender as a primary animation editor, I use it more for modeling and depending on your experience with it, you may know more ways to make adjustments, or try importing your entire character rig into iPi Studio and then re-export it, but I don't think Blender imports FBX files correctly from iPi, the bone orientations are messed up, so DAE, or BVH and re-targeting may be the only options in Blender, but Webanimate may be a more useful alternative to Blender for animation editing, or pre-setup in BVHacker for some fps, or other changes first.

Maybe some other users can weigh in on this topic also.

I hope some of this helps.

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I'm trying to understand wich program could be better . . . I'm not a pro animator wth Blender . . . I just know how to rig, move and interact with the bones and a little bit of keyframe . . . nothing more. I'm a beginner. The first time I tried to correct some animations from ipisoft to Blender I found a mess and I just gave it up; as you said there are problem with fps //fbx import // and then I never understand how can I modify all the frames the program import from the animation made with ipisoft (too many frames to edit . . . .60 per second) . . . it appeard to me like an wasted effort.Mayeb this is caused by inexinexperience . . . mayeb there's a way, like the one you linked before. I'm trying to understand right now.

Anyway . . . it's the first time I see WebAnimate. Only a quick question: watching some videos like this https://www.youtube.com/watch?v=dF8YA3iy8FE , it seems that the program is very very powerful. The auto set, modifing few frame, is so strong. You change the position of a bone in a particoular frame and the program set the frame before, fixing a lot of the animation.

For example: If you rotate the head in few critical parts, it will fix all the animation, without hours of work. The result is impressive.

My question is: do you think could be worth fix the rotation of the hand using only this program (webanimate), without the ps move? Or the controller for the hand are quite comulsory for a decent result??

Thank you!

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All I really use now for tweaks is Webanimate, just takes a bit to get used to it like any other program and its own bugs and it too has a 60 fps import issue for BVH, (for me anyway), but you can import as 60 fps FBX with no problem, make offsets, and then export as BVH or FBX. I also do a lot of work around for many issues and programs.

Yes, you could manually manipulate hand rotations, but that's a lot of work and not as natural as would be with Move rotations already there, would also depend on how much actual hand motion is needed and how long the take would be for manual manipulations to be effective.

If you are a beginner, Blender is one of the most difficult programs to work with, it doesn't follow a standard or similar UI as any other, (a very powerful free editor though), so Webanimate would probably be easier for you, but that's only for skeletal manipulation, no cloth, texture, dynamics editing, but then you can re-save as an edited file and import into Blender semi-fixed, then re-target as described in that tutorial series.

Webanimate has a 14 day trial, but is only $100 or so for a major version lifetime license per machine (node locked license).

Really depends on how good your base animation is, as to how much work in clean up you will need in post, so get that pretty good first, but no need to try to manually manipulate too much in iPi Studio, it;s a bit tedious to do so, but can be done, some will be needed just in using iPi's auto-clean features, but it solves a lot.

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Thank you so much! Your posts were very clear and useful! Thank you again!