Body Part Position Not Holding to Keys

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Old 05 May 2013   #1
Body Part Position Not Holding to Keys

Hey there,

I'm new to MotionBuilder and animation in general. I'm working on a game project that I'm currently creating animations for and it has been a learning experience, but I'm running into little issues that I believe are complete user error so I need some input.

I am creating idle poses for each weapon the player will be using. Each pose is animated onto one frame out of 46 total frames. For example frame 0 is a rifle and frame 33 is the pose for holding a chainsaw. I set a full body key frame onto each frame as I complete the pose, but when I modify the left arm of certain poses it subsequently moves that arm of the character a few inches off on every frame. So I have to go back through and reset the arm back into its proper position, which in turn moves the arm on the latter frames and creates and endless cycle. Why is this happening? I have each frame keyed so the rig should be locked into that pose and should never be changed by editing another frame.

A bit more random information: I put these poses on its own animation layer. The Base Animation layer is a t-pose because at the time I planned on adding a run/walk cycle to it. As I learned the program more I think that might not even work out or be necessary so I'm bringing this up in case this is for some reason the issue. If it is, how do I move my poses to the Base Animation layer?

Try not to cringe too hard at my noobish techniques. Thanks in advance!
Old 06 June 2013   #2
It could be the new character solvers messing things up. Go to your character rig, then set it to use motionbuilder solver rather than HIK 4.5 or the other... whatever it's called. I can recall most of them except the standard mobu one is a bit broken... at least when I tried them. It could also be roll joints, might be worth turning them off or switch between their settings.

Let me know if it helps!
Old 06 June 2013   #3
And regarding the t-pose on layer one, it's not necessary. Make your run on a separate take, then just add whatever pose you want additive on a layer, instead of the opposite.
Old 06 June 2013   #4
I did some quick testing on swapping the CharacterSolver and as far as I can tell the left arm no longer loses translation when I modify other frames. I appreciate your help, Erik!

The only qualm I have with using the mobu solver is when I am creating an aim matrix for a rifle, I rotate the upper body control up which moves the shoulders > arms > hands as well so the rifle is aimed straight up, then I pin the hands in place (translate + rotate) and move the upper body back making the spine straight again, then I move the hands forward making the character aim the gun straight up in the air with his hands still perfectly on the rifle. Using mobu's solver though pinning the hands does nothing when you rotate the upper body. It moves along with it. Any way I can keep the pinning override on HIK, but keep the accurate solving that comes with the mobu solver?
Old 06 June 2013   #5
Is the hand controller in IK mode? (green ball..) otherwise pinning will only lock it if you pose using the full body setting. If you use body part, rotate the torso when the hand isn't in IK the pinning won't be evaluated. It's something that you'll learn with time (how the pinning/IK etc works depending on if you're in fullbody, bodypart or selection.
Old 06 June 2013   #6
Ah excellent! You made my work flow much cleaner/faster with results that I expect. Much appreciated.
Old 06 June 2013   #7
Glad I could help!
Old 06 June 2013   #8
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