Inverse kinematics issue

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beeheemooth

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Aug 9, 2018, 5:35:28 PM8/9/18
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Hello.

I want to do squats animation using IK. I have a chain of bones that I fix in the initial (origin) and final (+shift) bone. But with the animation, the last bone is not fixed firmly, but moves along with the foot. In the Function Editor, the level of the foot doesn't have keys to move, but it moves because of the bone. What can be the solution in this situation?




P.S. It's strange that gif does not work. Before clicking the "Publish" button it worked. This is not the first time it happens.

ezgif-4-cd6d8dca54.gif

beeheemooth

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Aug 9, 2018, 5:44:14 PM8/9/18
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joshua shute

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Aug 10, 2018, 2:30:07 PM8/10/18
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I think the gif issue is that it was added as an attachment. I think if you add it via this buttonScreen Shot 2018-08-10 at 10.40.11 AM.png it should play.


the video link wasn't playing for me either so i'm not exactly sure what the issue is. but this is how I would squat with very little fuss. detach the feet from the rig for the frames your character is squatting; this ensures that the feet appear to be firmly planted on the ground and don't move around. the rig's root should be around the waist or torso. lower the rig in animate mode and then use ik to adjust the placement of the legs and torso into the final squatting position. reattach and position the feet when needed. a tip, adjusting the easing of the calves to be more steep will keep your ankles in place.


IK in opentoonz can be a bit wonky and gets harder to control as rigs begin to incorporate "peg" columns.

       

beeheemooth

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Aug 10, 2018, 4:50:58 PM8/10/18
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I unloaded a short video on YouTube

https://www.youtube.com/watch?v=HS5bEMrHuAg&feature=youtu.be


It's strange, but when I detach the leg from the rig, it moves to another place (although I delete all the keys in advance). It moves to the same distance as when the animation (when rig is on).

joshua shute

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Aug 15, 2018, 6:02:31 PM8/15/18
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with your example, what I'm suggesting is 

A) between frames 2 and 5, move the drawings of level M from column 7 to an empty column(let's say column9). you may have to reposition and scale the art in column 9 using the animate tool so that the art lines up with it's placement on frame 1.

B) merge column 7 and a blank level  for frames 2-5. this will "bake" the rotation, position, and scale of column 7 and it's parents into the new level.

there are a few other ways to get the same effect but basically you are looking to have the art of your foot (column 7) moved to a different column so that it is no longer attached to the rig and thus is no longer affected by the ik chain.

hopefully down the road opentoonz will allow us to shift click (lock) both ends of an ik chain while still being able to move the bones inbetween but it doesn't seem to be possible yet.

"It's strange, but when I detach the leg from the rig, it moves to another place (although I delete all the keys in advance). It moves to the same distance as when the animation (when rig is on)."
what do you mean? if the leg is detached, there should be no movement driven by the rig.
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