Need help with Motionbuilder retargeting

[jsonedecker]

I know this isn't a MB help area, but it's one of the places I know of that people frequent who use it and I am pretty must frustrated out on this problem...

I am trying to convert our game motions from a bone skeleton over to a Character Studio Biped. We captured using our OptiTrack system, processed in MB then imported into Max. Everything worked great, but now we need to put all that work onto a Biped rig as our pipeline has changed. So I am trying to use MB to retarget those motions onto a CS Biped ready skeleton in MB that is fully characterized and ready to go.

That being said, I am pretty much a novice with Motionbuilder and am running into some issues. I tried what I thought would be the easy way and exported the base motions as bvh so I didn't need to retarget. Unfortunately Biped didn�t like the naming convention. So I am trying to retarget the motions onto the Biped rig itself.

Everything works fine except the arms are crossing over the chest too much. I attached an image that illustrated it� the large character is the source and the smaller one is the Biped characterized rig I am trying to get it onto. The scale is different because when we did the initial capture/cleanup our game scale was 2x what it is now, but that didn't cause issues getting into Max. Anyway, in my bone skeleton the clavs are linked to the top spine bone and not the nech as it is in Biped. I tried this with the clavs linked both ways and got the same results.

Sorry for the rambling, but I�m pretty frustrated at the moment because I thought the whole point of MB was it�s ability to retarget motions using the Control Rig easily. Once it�s on the control rig then 2 control rigs should �talk� seamlessly as the control rig is the common link between 2 different skeletons.....or so I would have thought.

Any direction on this would be greatly appreciated.
[img:center]http://www.blackfootstudios.com/temp/retarget.jpg[/img]
-John

[seanboyette]

John,

Are you exporting from MB to Max via bvh?
or are you exporting from Arena to MB via bvh?

if it is the latter - you should consider markerssets and then use those to drive an actor - and the actor to drive your character.

I can go into a bit more detail to assist with Arena and MB.

Sean

[jsonedecker]

Hey Sean.. how have you been! I wasn't sure if you were still around, but I see that you are. I haven't come to these forums in forever myself since things with the capture system have been working fine.

So, to the problem.... All those captures we did last year were processed and made game ready in MB so Arena isn't needed in this part of the pipeline. Basically, we need to change everything over to use Biped. Anyway, I then just imported the fbx on top of a bone rig in Max and the motion went on that perfectly. Now I need to get those onto a Biped rig and need to go back into MB. I have the original game ready MB files and tried exporting to BVH from MB but Biped in Max doesn't like the bone naming.

So we are already past the Arena stage and I just need to get final motions from a bone rig to Max a Biped rig. Isn't that what ControlRigs are for in MB?

[seanboyette]

John,

I lurk around from time to time...

It may even be easier for you - from MB 7.5 (I think) and up there is a BiPed Character Rig built in, so you may be able to use that, and have it driven by your other game Ready FBXes and and then export that perform your normal process.

(does that make sense?)

Sean

[jsonedecker]

I got it figured out.... My reference T-Pose for the Biped rig had it's arms down at a 45 degree angle but the pose that was used for all the motions had then strait out to the side.

I would have thought MB would be smart enough to handle that, but I guess not. Anyway, the issue is fixed by matching the Biped's ref pose to the one used for the motions originally.

-John

[neill_solow]

For MotionBuilder I have written csm (character studio markers) import/export plugin, which is suitable for optical mocap->biped pipeline. You can find it on my blog

[jsonedecker]

Yeah, I use the x64 version though. I am the one that asked you on CGTalk forums about it the other day.

-John

[neill_solow]

, I will try to compile plugin under 64bit...