Moho Animation Forum

I try to create a convincing waving hair motion just with bone dynamics, but without success. Does anybody have a setting for the 3 values which works for a bone chain when I just move the root bone?

I recorded a video, I hop it helps:

From what I'm able to understand, the bone dynamics settings work like this:

Torque force: This determines how much your bones will bend
Spring force: This determines how quickly your bones return to their original state
Damping force: This determines how much your bones will wobble

For long hair, I use the following setting: 2, 1.50, 5.50

It gives a good amount of bend and doesn't wobble. If you don't like how much it bends, reduce the torque more to around 1.5 .

Still doesn't work for me, but that's maybe because of my setup.

They want a very smooth and detailed movement of very long hair, so I created a very delicate bone chain with 30 bones:


If I select all but the root bone, apply your values, and then create 2 rotation keys for the root bone, this is the result:


Nice in itself, but more suited to Medusa than to just hair in the wind.

I tried another one, with the same bone setup, and a technique Victor explained in a video: select all bones, create 3 keys, then selet all bit one bones, shift their keys some frame, selet one bone less, shift, and again and again.


This gives the kind of wave I need, but it's too static and repetitive. Ideally I just want to key the root bone, so I can put in some variation in timing and angle, and let physics do the rest. Victors examples work well with shorter strands of hair, but don't create the sine wave I want.

Oh well. If this doesn't work, I'll do it FBF in TVP anyway ...

This is an old test I've made, I don't know if this could help you?

https://www.dropbox.com/s/pa1metb75nw8y ... .anme?dl=0

But in my opinion, i think there is too much bones in your construction.
I dont have time because i must go to work, but perhaps In the evening i will make a try.

Some point based waves that move more quickly combined with a VERY simple bone dynamic over a larger area of hair/locks will get a great result.

Lychee: thx, but it seems to be a v12 file and I only have v11 (or it's just broken).

Thx for all the input, I will experiment a bit more but, if I don't get a satisfactory result, stick to FBF.

a thought. start with the hair curled -- chain of bones with a target on the end of the chain so that you can pull to straighten - animate the target (noisy interp) and bind the hair layer to a bone that uses dynamics -- feel free to adapt to suit your needs (or tell me it's no use for what you need!! )

https://www.mediafire.com/?6ii7j15we773tjh

[edit] ah - just noticed you're on V11 https://www.mediafire.com/?gc7mgyvnj5dfn7b this is the same -- some issues with the vector layer because of Bezier - but fundamentally the same

I seem to remember an animated version of curve profile being useful for this, somewhere at the back of my mind...

My link to the top was updated in a anime studio format, and i worked on a new test, tell me what you think about it:

https://www.dropbox.com/s/fjvd7eargn9sx ... .anme?dl=0

jahnocli wrote:I seem to remember an animated version of curve profile being useful for this, somewhere at the back of my mind...

ah -- yes ..... maybe it was this: viewtopic.php?f=12&t=30264&p=175547

That's the one! I'm sure that could be adapted for flowing hair...

Nice, but still doesn't create that sine wave I'm looking for. I added some bones of the same length and with the same dynamic settings, but the whole thing just keeps looking like a porcupine's spine.

I think this is a dead end, because we have a bone chain with some attributes for dynamic, but only one bone causing any motion and this is handed down through the chain. Hair, OTOH, is affected on all of its parts by the same force (wind), so we'd need a kind of bone which is affected by its parent for position and rotation and at the same time by wind.

The problem is that there are so many variables that compound to create , turbulence.
The length, and binding weight both effect the bone as well as the dynamic values.
The is dkwroot's point wave which is great, and bones are great for automation and randomisation, unfortunately it does always become random.
I would suggest any other method , cycles , what ever you could use one base bone with dynamics to trigger a smart action, but I don't think a total dynamic solution could get exactly what you might be after ( if you do want a perfectly rhythmic wave).
I have had great results with dynamics , though you just have to juggle the weight, length and dynamic values, which are all effected by the inertia of the parent.
You might have a great result from gentle parental motion , but find it all goes to hell with more aggressive motion.
That is why I use the methods I do, start with a heavy bone and get lighter, if you can get down to two bones then all the better.'
Better still, one slow dynamic with point motion on top.
See the flag in my Tern Tale animation @ 1:40
btw there are plenty of dynamics in that film.
https://youtu.be/ktw3lD60bEc