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danb
03-19-2007, 12:18 AM
I have a character with 4 arms and 2 legs, maybe some of you have seen it here on the forums. I have rigged the character using the biped control rig in MB 7.5. I have applied some motion capture clips to the character. Everything except the 2 lower arms of my character follow the motion clip. I have parented the 2 lower arms to the hips and they follow fine, but do not recieve the motion clips (as i figured this would happen).

I would really like the 2 lower arms to have the exact same aniamtion applied from the motion capture clips, as the 2 upper arms have. So that all 4 arms have the exact same movement.

Any ideas?

I know i could just keyframe the lower arms but i like the ease of use of the motion clips and editing them. I'm sure this question could help others as well.

danb
03-19-2007, 12:21 AM
I decided to post a pic of the character...

sdyer23
03-19-2007, 03:22 AM
danb,

Perhaps you could use motion Override tracks for the arms? Just take the motion you got for the upper arms and save them out as tracks, then import them back into MB as overrides for the lower arms. Perhaps this could work? Hope this helps, nice character by the way. Good luck to ya!

-Tux

Sammer
03-19-2007, 03:26 AM
Hey Dan,

Yeah, so few four armed people around to generate mocap from!

A couple of suggestions for you....

Should you really want the second pair of arms to move exactly as the first (not my first choice as it would be less interesting and give a whole new meaning to 'twinning') you should be able to set up something using simple constraints. A rotational constraint that has the left lower arm constrained to the rotation of the left upper arm, left lower forearm constrained to the rotation of the left upper forearm etc. etc.

To allow you to break up the animation yet still use motion clips, you might consider constraining the lower arms to the arms of a hidden character or skeleton (regular 'ol two arm, two leg variety). That way you could apply a motion clip to the hidden rig and have it drive the second set of arms of your four armed character.

Just a couple of quick thoughts off the cuff.

Good luck.

Sam

Sammer
03-19-2007, 03:42 AM
I don't know if that would work, Tux.

You don't need to save and re-import to use an overide track but isn't the problem that the animation in any of the clips is on Left_Arm, Left_Forearm, Left_Leg etc. and when you go to reuse it MB will only retarget it to the part of the rig with the same name?

Once there is animation on the lower set of arms you should be able to reuse it just like every other appendage.

Which does bring up a question, I'll have to check it out and see but.... if you save a motion clip as an ascii file how does it look when you open it... could you simply rename the original arm animation... or copy it and add the extra 'Lower' prefix to each part.....?

We'll have to see......

LoneCanuck
03-20-2007, 10:21 PM
I have a character with 4 arms and 2 legs, maybe some of you have seen it here on the forums. I have rigged the character using the biped control rig in MB 7.5. I have applied some motion capture clips to the character. Everything except the 2 lower arms of my character follow the motion clip. I have parented the 2 lower arms to the hips and they follow fine, but do not recieve the motion clips (as i figured this would happen).

I would really like the 2 lower arms to have the exact same aniamtion applied from the motion capture clips, as the 2 upper arms have. So that all 4 arms have the exact same movement.

Any ideas?

I know i could just keyframe the lower arms but i like the ease of use of the motion clips and editing them. I'm sure this question could help others as well.

The slow solution:

You could always copy and paste animation. Select the source bone, press Ctrl-C, select the target bone, and hit Ctrl-B. This will bring up a pop-up that prompts you what channels you want to copy. In this case, it would be Local Rotations.

Do this for every bone in the arms.

The FAST solution:

Create a Relations constraint.

Inside the Relations window, select all your animating arm bones and ALT-drag them into the window and set them as Source. Select all those boxes, right-click and choose "Local Transformations".

Select all your target arm bones and ALT-drag those into the same Relation window. Select all those boxes , right-click and choose "Local Transforms"

Now, you should be able to wire the Rotation channels from your source arms to your target arms.

If you want to offset or change the animation, you will need to plot all the bones first THEN deactivate the constraint.

Hope this helps,

Lone_Canuck

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03-20-2007, 10:21 PM
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