topic Re: Animate Bones Directly in FlexSim Forum

Animate Bones Directly

mark_gormley — Thu, 10 Jan 2019 17:00:59 GMT

[ FlexSim 19.0.0 ]

Is it possible to use the new functionality to edit bones directly to create new animations for the standard operator? I am trying to do this but find that once I change the bone positions the new positions are applied for all other animations.

I have created an example where i duplicated the walk loaded animation and moved a single bone in the arm to make the 1 hand by his side. This animation itself then works ok, but if i switch back to any other animation (such as the walk animation) the arm is now in this new position and i cant seem to change it. Am I misunderstanding what the directly editing of bones should be used for?

Re: Animate Bones Directly

philboboADSK — Thu, 10 Jan 2019 19:58:12 GMT

When animating bones directly, the edited bone is applied as an offset after any animation clips.

So if you want the existing animations that use animation clips to be unaltered by your altered bones, add a keyframe to the beginning of those clips where the bones are in reset positions.

You can use the "Reset Bone Positions" menu option to easily set all the bones to their reset positions.

Re: Animate Bones Directly

mark_gormley — Fri, 11 Jan 2019 09:45:56 GMT

Hi Phil, thanks for the reply.

I have tried doing what you suggested as shown in the attached GIF, but i can't get it to work:

I have also tried editing the new animation to include a keyframe where the operator has its bones reset at the start and end. This sort of works, but when i play the animation he obviously jumps to that pose and back out of it again. Also if i don't finish the animation exactly at the start or the end then any further animations i play have the newly offset bones.

Re: Animate Bones Directly

philboboADSK — Fri, 11 Jan 2019 14:27:18 GMT

You are storing the modified bone position as the keyframe at the beginning.

Reset the bone positions before adding the keyframe at the beginning of the Walk animation so that the keyframe's values are the reset positions, not the altered position.

Attached (reset-bone-position-keyframe.zip) is a video showing the steps.

Re: Animate Bones Directly

mark_gormley — Fri, 11 Jan 2019 14:52:34 GMT

Thanks Phil, that has now got it working as i wanted.

Just to help me understand further, even though i created the keyframe first how come it didn't update the bone positions when i clicked on it and reset the bones again?

I guess this may catch a few other people out so i didn't know if it would be a good suggestion to automatically add in a new keyframe to all animations that use animation clips once you choose to edit the bones directly, this will stop any of them breaking?

The user manual is also not crystal clear on this, it explains that "You may want to use this option to add a keyframe at the beginning and end of any animations that animate the bones directly, especially when combining direct bone animations with animation clips." this may want re-working to say what you have told me instead.

Re: Animate Bones Directly

philboboADSK — Fri, 11 Jan 2019 14:57:19 GMT

The animator's UI for editing existing keyframes is finicky at best. I'll add a case to the dev list to look into that and your other suggestions.

Re: Animate Bones Directly

lucas_klein83QQC — Wed, 20 Mar 2019 14:12:09 GMT

I came across this problem too. The base position became the last bone position of a new animation that I created. If the main animations (Walk, Stand, WalkLoaded) could have an initial base keyframe, would help to return to the initial state.

Re: Animate Bones Directly

ralf_gruber — Thu, 24 Jun 2021 09:55:06 GMT

@Phil BoBo

Your way to modify keyframes of bone animations seems not to work in versions after 19.

Here is a video where I try to modify an existing keyframe. As you can see, the change I made is not taken into the animation (the menu option on rightclick of the keyframe, that is not shown is "Update Keyframe"):

Your browser does not support HTML5 video.

It does work though, if make make the change first and create the keyframe after:

Your browser does not support HTML5 video.

Is there any way to edit an existing keyframe still?

Thx for looking at this.

Re: Animate Bones Directly

philboboADSK — Thu, 24 Jun 2021 14:58:31 GMT

Yes, it looks like the Update Keyframe option isn't applying changes to Bones components. I'll add a case to the dev list.

Next time, you should ask a new question instead of hijacking an existing question with an accepted answer.

See Best practices for using this Answers site

5. Follow-up questions. Sometimes it's tempting to ask a follow-up question as a comment to an answer, or even more inappropriately, as a new answer to your first question. New questions that can stand alone should be posted as brand new questions.

Re: Animate Bones Directly

ralf_gruber — Thu, 24 Jun 2021 15:04:29 GMT

I will. Thx