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Path constraint for a bone chain


detbear

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Hey Everyone.

 

I have a chain of bones. (Bone 1, 2, 3, 4, etc.)

 

I'm constraining them to a spline using a path constraint. I want them to move along the path keeping their distance.

 

But when I constrain each bone to the path, they attach to the same start point right on top of each other. Is there a way to offset each

bone so that the chain does not group together to follow the path?

 

Thanks,

 

William

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It can be done and will be easy to do in Animation:Master!

 

 

BasicWormCrawl.mov

 

 

 

I used that basic workflow to do my Worms! animation and played with the staggering and interpolation between keys to make for the squishing crawling motion

 

8wDmFzHPXTA

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That's really cool Robert. Thanks for that...

 

Is there a way to work out the timing/spacing so that you can get the bones to sit in a parented

location so that there's no spaces or overlapping?

 

I have a bunch of bones too which complicates things.

 

That's a great tutorial also.

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That's really cool Robert. Thanks for that...

 

Is there a way to work out the timing/spacing so that you can get the bones to sit in a parented

location so that there's no spaces or overlapping?

 

Parented location... do you mean the bones have to be literally attached and not just look like it?

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But when I constrain each bone to the path, they attach to the same start point right on top of each other. Is there a way to offset each

bone so that the chain does not group together to follow the path?

 

Perhaps the easiest way would be to parent all the Bones hierarchically in the PWS and then when applying to the path (which could just be a controlling spline BTW) use Compensate Mode to keep the Bones from moving. Alternately in an Action, you could adjust the ease of each Bone to move it into the ideal location. Then you could just drag/drop the Action wherever needed.

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Ok.....I've got preliminary tests on the way, but nothing to show yet.

 

The path has to run in a stretched oval loop. Like a chainsaw. Since the path can't repeat, I looped it around several times.

BTW....Is there a way to loop the path flow when it reaches the end?

 

The bone chain goes the length of the entire path...like a chain on a chainsaw.

 

Then things become a bit more complexed.....I need several of these paths running side by side. Kind of like 3-4 chainsaw chains sitting next to

each other.

 

I'm not sure how to duplicate this in the same seen without doing them all separately. I have to also be able to move/ animate each of the individual paths which gives me control over how the bones chain is moving.

 

VERY Complexed...but I have gotten some success with a single path. But I don't know how to have the chain run around the circle more than once. Simply looping

the time doesn't work because I have to control the path itself in animation longer than the loop runs.

 

:) William

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Ok.....I've got preliminary tests on the way, but nothing to show yet.

 

The path has to run in a stretched oval loop. Like a chainsaw. Since the path can't repeat, I looped it around several times.

BTW....Is there a way to loop the path flow when it reaches the end?

 

It will be necessary to slightly overlap the beginning and end of the path so the bones can return to their starting point.

 

the "post-extraoplation " can make the looping automatic

 

The trick is to force a keyframe on every ease channel at the first and last frames that the spacing is properly staggered and delete the 0% and 100% keys outside of those

 

example PRJ

 

SimpleWormDemo03_loop.prj

 

The bone chain goes the length of the entire path...like a chain on a chainsaw.

 

If it's like a chain saw, do you really need to traverse the entire loop? couldn't you just travel far enough to reach where the next identical link started and repeat that? It would look the same

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I have the motion working ok.

 

Looping it is the concern. When I say loop I really mean that I need the bones to go around the path more than once.

 

It can't be a restart on a previous frame.

 

I'm not sure where to try and set keys at the ease frames....Not sure how to tell which those are. Also if I set more keys it seems like

that will lock the speed of the path. I hope to be able to adjust the speed of the path if I need to.

 

Ultimately, I need to be able to manipulate the path splines themselves while the bone chains rotate around them. So the paths themselves will

have control bones also.

 

No....this is not a Tank Tread....so an animated decal won't do. :)

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Ultimately, I need to be able to manipulate the path splines themselves while the bone chains rotate around them. So the paths themselves will

have control bones also.

 

You could create the path as a spline either in your main Model or as another Model added to your main Model (either as an Action Object or simply put in place. Then you can easily animate that spline, moving around it in a circular motion and then... you wouldn't even need to animate the object following the path... but you could if'n you wanted to via the Ease such as when/if you want it to move in reverse.

 

Paths can't be circular if you use the standard Path in a Chor but they can be if created as a Model and then dropped into a Chor.

In this way, any spline can be a Path, even the splines on your main Model.

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Is this something you could show me? If I saw it the solution might be more obvious.

 

Changing the path will probably have the effect of changing the length of the path which will either stretch or squish the distance between bones, so that is an added complication.

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Yes...I am using a modeled spline rather than a straight out path in the choreography.

 

Robert, I sent you a few files.

 

It's so hard to explain this stuff in text. Not you guys fault at all. My own Brain freeze. :)

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Yes...I am using a modeled spline rather than a straight out path in the choreography.

 

Robert, I sent you a few files.

 

It's so hard to explain this stuff in text. Not you guys fault at all. My own Brain freeze. :)

 

Call me on this. I'm not sure what I'm looking at.

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