Help! My bone's gone crazy!!

[Sketch_Turner]

So basically, I'm making a running animation for the character while viewed from the back. I move the limbs using target bones, and everything's working smoothly in the action editor. It also works well when I insert one reference into the mainline. But if I add another reference after that, suddenly all hell breaks loose: for some reason one of the shoulder bones just keeps snapping madly back and forth, like the program can't decide which is the optimal way to the target bone.
(I would've posted a video of the issue, but TinyPic doesn't seem to be working at the moment. Could you you suggest alternative services?)

[Greenlaw]

Without an image or video, just guessing: You might need to set a 'preferred' angle for the IK to work the way you want. After targeting the bone, use the Rotate tool to turn the bone in the opposite direction of the current bend. You don't have to go far--typically, you only need to go far enough to pop the leg in the direction you want. After this, you might need to move the keyframe to just before the frame where the problem starts.

As for video hosting, almost everybody here uses YouTube or Vimeo. The YouTube and Vimeo buttons on the Reply page make this easy to post the move inline. TinyPic is better for images and animated GIFs.

[Sketch_Turner]

Okay, here goes.

The most baffling thing to me is that it continues with this behaviour even after the animation has ended and the character is supposed to be still.

https://www.youtube.com/watch?v=2YSZNOg ... e=youtu.be

(for whatever reason even the Youtube button doesn't want to process my link, so I'm posting it as is)

[Greenlaw]

If you hover over the YouTube button, a tool tip pops up to explain the expected format.

In short, you only need to provide the video ID, not the entire link.

[Sketch_Turner]

In short, you only need to provide the video ID, not the entire link.

Yeah, I got that, but it still displayed it only as text

[dueyftw]

Okay, here goes.

The most baffling thing to me is that it continues with this behaviour even after the animation has ended and the character is supposed to be still.

https://www.youtube.com/watch?v=2YSZNOg ... e=youtu.be

(for whatever reason even the Youtube button doesn't want to process my link, so I'm posting it as is)

Can I see the file?

I'm busy so give a few days.

Dale

[Sketch_Turner]

Here's the file: https://drive.google.com/open?id=0B_7S6 ... 0NPdXk0TUU

It seems like something's covertly affecting the target bone: even if you delete all the keyframes with bone translation, it still moves. I have no idea what's causing this motion.

[dueyftw]

OK.

I got the file. I took a quick look. You have the target bones moving the arms. You made the arms straight. They should have an slight angle and that would keep the angle that you want.

I tried change it to fix it, but it seems that doesn't help. So I'm going to need some more time with you file. Give me a few days.

Dale

[synthsin75]

You just need to delete all the bone rotation keyframes for that forearm bone (B12). It's trying to follow the target AND do its own rotation.

[Sketch_Turner]

You just need to delete all the bone rotation keyframes for that forearm bone (B12). It's trying to follow the target AND do its own rotation.

YES!! Thank you, this solved the problem! Those sneaky rotation keyframes, huh...

One last question: why does the reference in the mainline look like this now



instead of this



and how do I fix this? Not seeing where the reference ends is kinda uncomfortable.

[synthsin75]

Your images aren't showing.

[Greenlaw]

As mentioned at the top, you can set a preferred angle for the IK by keyframing the targeting bone's rotation. Sounds like you set too many preferred angles, perhaps arbitrarily.

In general, a slight bend in the targeting bone bone at frame zero will define the 'default' preferred angle for the IK. You should only keyframe the rotation angle (typically lower arm or lower leg bone) when you need to change the direction of IK during animation. This rotation keyframe should be set at the frame where you wish to cange direction, but before you set that key, you should set a duplicate of the previous keyframe in the frame just before it. (I guess you can use step frames to do this and have fewer keys, but for this purpose I normally just double-click the timeline to create a copy the previous key.)

[synthsin75]

If you're talking about the referenced action names not showing, you have a lot of unnecessary stuff keyframed in your action. Unnecessary single-frame layer transforms and bone rotations/translations will make the ALL animation channels not show the action name...unless you select a bone that has more frames keyed. Removing all the unnecessary keyframes will make the action names always show. Easiest way is to select what needs keyframes, Edit>Select Inverse, and delete the selected keyframes...plus any straggler single-frame keys.

This includes all the sublayers in the action, and you probably want to cycle all the keyframes too.