Hi,
Are there any advanced documentations or tutorials on how to best set up the MB Actors to the marker data?

I’ve recently started to build characters that have the same proportions as the actors (real humans, not MB Actors) we’re working with, in hopes that this will yield the quickest and best out-of-box results from our mocap. While yes, it is an improvement over our previous attempts, it’s still not 100%, it’s more around 80% good (I’m aiming for 90%+, obviously it’ll never be perfect).

To go about this, I have turned on Actor Pivots, and lined up the orange pivots of the Actor ‘bones’ as best I could to our character. I then only rotate the joints into the marker data T-pose when setting up the actor, so that the Actor joint lengths don’t change at all. However, once plotted, the character’s arms float slightly above the Actor, causing the need for T/R Reach to be near 100% (which can cause arm locking).

I should note that the biggest difference between our characters and the MB Actor is that we have 4 spine joints and the Actor only has 3.

All the tutorials I’ve read so far end with: “Crank the Shoulder Reduction to 75-100 to get the best results.”

... ok, so the shoulders/clavicles should look stiff as a board? sigh.

Any leads or advice would be much appreciated!

Thanks
-Horse

Hi Horse,

I have a tutorial that might help with your Actor set-up

http://mocappys.com/?p=14

Have you tried turning on match Translation for the chest and only using match rotations for the arms. It’s possible the extra joint in the spine is slightly changing the rotation angle of the spine of your character which in turn will force the arms out of position.

With regards to the shoulders - It’s always worth rotating them up by about 10-20 degrees when you are T-Posing the actor if you are not already doing so. As most people raise their shoulders slightly when they lift their arms to the T position this needs to be replicated on the Actor or it can lead to drooping shoulders.

It may also worth checking the angle of the arms down the length of the joint. You may find your performer wasn’t standing with their elbows perpendicular to the floor like the default Actor T-Pose. This can cause your elbows to solve incorrectly.

Hope this all helps and doesn’t add to the confusion.

Let me know how you get on

//Mocappy

http://www.mocappys.com

Thanks for the replies!

We’re getting closer with the models, I’m convinced it’s almost impossible to replicate what’s going on with the Actor’s spine and arms 100%, especially since our joints are placed somewhat differently in our characters (i.e spine and pelvis joints are an inch or so pushed back on the actors)

I’ll mess around with the marker sets, we have tried a few different ways of attaching the markers to the actor, but that was before making this new 1:1 scaled character. Our animators discovered the rotating shoulders ~15deg fix too, but I still find it weird that it needs to be done.

Ideally I don’t want to use any of the Motion Reduction settings, but they do provide some support if the neck, shoulders or head are over-emphasized in the data. Reach is also beneficial, more so than Pull imo, we key both of these throughout the duration of the initial mocap cleanup process. But with the 1:1 scale characters, you hardly need to key them as often as we previously did, so we’re getting some decent results thus far.

Mocappy:
It looks like you have a ton of info on your site, I haven’t gotten a chance to read through it all but it seems very helpful. Thank you!

If your having issues with still needing to use reach when targeting, then one more thing to look at is the stance when “characterized” as any difference between this stance and the source stance will create an offset between the actor and the character.

Great tips and site from Mocappy though, plugging your site on my blog:)

Brad Clark
Co-Founder: Rigging Dojo-Teaching the art and science of character rigging
Author: Inspired 3D Advanced Rigging
The Character Animator Toolkit for Motionbuilder :available now: