Is there a way to make a dynamic constraint only go halfway up a chain of bones?

[luckbat]

So, against my better judgment, I'm working on a new rig for my cloak (it's less complicated than it looks).

 

[attachmentid=14395]

 

As you can see, I've got a chain of bones running down each spline of the cloak. I'm using some constraints to make the upper part of the chain wrap around the wearer's shoulder and arms, but the lower part of the chain is sticking straight out, since each link is a child of the one above it. Obviously, I'd like the lower links in each chain to swing freely in accordance with gravity and inertia. (Maybe the middle link could be set at 50% to ease the transition.)

 

I thought about using lag, but it seems like dynamic constraints make more sense here. But I'm having trouble setting up the dynamics. For obvious reasons, I don't want the dynamic constraints to travel all the way up the chain, since top two links are controlled by constraints.

 

Can anyone tell me the correct way to assign dynamics to only the bottom half of the chains, here? Should I...

 

1. Break the chain parenting?

 

2. Override the dynamic settings midway up the chain?

 

3. Use a second chain constrained to the first?

 

4. Something else?

 

I did some experiments, but they only left me more confused...

[trajcedrv]

I think that your best guess would be 'not attached to parent'... I would certanly do it that way

[heyvern]

This is just my "guess" if I were trying to do what you describe...

 

At the point in the chain where the dynamic control should end... remove it from the hierarchy of bones. The last bone in that chain which is dynamically controlled would then have a translate too and orient like constraint to the bone that is controlled "by you" with other constraints.

 

This would sort of... keep it in a chain... but stop the dynamics half way up.

 

I would only suggest this if there is no other way to stop the dynamic constraint.

 

Vernon "!" Zehr

[Stuart Rogers]

I vaguely recall this topic being touched upon by Bob Croucher in his Dynamic Constraints Tech Talk. But I could be wrong. I usually am.

[luckbat]

Well, Bob constrained the midpoint of a chain to a null, then moved the null around. I was as excited as the rest of you to see that trick, but the technique doesn't help me much here.

[luckbat]

Okay, the good news is, breaking the chain parenting and then using Translate-To constraints to re-attach the lower, dynamic half of the chain worked like you'd expect. The bottom half of the cloak swings around freely in response to the movement of the upper half.

 

The bad news? Well, it's a fairly abrupt transition, which is why I wanted the middle bones to act as intermediaries, angled about halfway between the upper bones and the lower bones. Except that I can't--the dynamic constraints override any other constraints that affect the middle bones' angular orientation. I can assign whatever "Orient Like" or "Aim At" constraints I want, but they're completely ignored once the dynamic constraints are in there. Thus causing the middle bones to hang down like wet noodles.

 

[attachmentid=14433]

 

I guess dynamic constraints are supposed to override all other angular constraints, so this is a feature, not a bug. But can anyone think of another way that I might get the middle bones to orient themselves halfway between "sticking straight out" and "swinging freely?

[robcat2075]

50% enforcement on each constraint won't work?

 

Well, if it doesn't...

 

- how about if the intermediate bone were a dynamic chain of it's own; a stiffer one. the rest of the bones(seperate chain) would then hang from it and be floppier.

 

- i had another idea but can';t figure out how to describe it