Beginner questions about simulation settings

Hello, beginner here.
I’m trying to get the feeling right in the simulation on the root.
So as you can see I have pose space on custom (even though I don’t quite understand what it is yet but Jason had it in one of his videos :slight_smile: )
With damp on 0 I would assumed that the Hips would be very bouncy and the enegergy would never deminiss, right?
Yet on the gif the hips is very droopy/floating.
What am i doing wrong? none of the pose spaces makes a diffrence.


Hey @Calle_Halldin, welcome to the forums! :partying_face:

Am I understanding it correctly that you’ve got the hip selected here, and that the Pose Damping on the hip is the one that is 0?

I can also spose Pose Stiffness at 0, meaning the hip - regardless of the space - should not follow your animation at all. Since it’s still hovering, there must be something else following.

What does your group settings look like? Is it also set to Pose Space = World?

I would suggest:

  • Leave Pose Space = Local/Inherit on all markers and groups.
  • And instead use the Pin Constraint when you want something following your animation in worldspace

That will make it clear what’s affecting your character in worldspace, leaving any Pose Stiffness to only deal with relative angles between limbs.

Hello, I seem to only have one “Group” for the whole body, thats probably not a good thing.
On the group it was 1 on stiffness and 1 on damp.
Messing with these didn’t do much for the hip.

Putting the translate motion to soft and lowered the values kinda got me where i wanted but now fingers are floating in the air and the whole body feels like jelly beans :slight_smile:
Still feel like I should be able to get what i want with just stiffness and damp? or is translate motion the answer but only on the hip?
To be clear, what i want is the hips to dip down once and bonce up and get back to where the control is, sorta.


It’s veery hard to see what’s happening with such a zoomed-in view.

My guess is your character is balancing on his own, in which case the stiffness and damping to affect his hip is coming from his legs?

Try this.

  1. Select the knee controls
  2. Set Pose Damping = 0

Alternatively, run Ragdoll → Select → Markers and set Pose Damping = 0 for every Marker in the scene. That should definitely have an effect.

That’s fine, that’s what happens per default as you assign things to the same character. You can select some controls and go Ragdoll → Edit → Group to make separate groups for things, but use those baby steps first.

Here’s every marker damping 0
Yes, it did have an effect for sure :slight_smile:

Haha, he’s clearly excited about the progress you are making. You’ll still want some Damping, it’s what introduces friction between each limb and keeps things from getting too exciting.

But from this view, I can see that he’s able to stand thanks to his feet being set to Kinematic. My guess is you’ve got limits that prevent him from relaxing. For example, if you’ve told Ragdoll that the legs are only allowed to rotate around Z, but then your IK handles are causing rotation around X and Y as well, then the limit and pose stiffness will start picking fights.

If that’s the case, either loosen up those limits or prevent your animation from rotating around those locked axes.

Things to try.

  1. Select all fingers
  2. Set Enabled = False

Does that keep him from dancing?

  1. Select the feet
  2. Set Behaviour = Dynamic

Does that?

If not, then Ragdoll → Select → Markers and set all Limit Range attributes to 0 until we’ve figured things out.

With all of the above set, the character should be fine. He should fall over, like a normal drunk; he shouldn’t be too excited about it. If that’s the case, then:

  1. Select the hip
  2. Run Ragdoll → Constrain → Pin
  3. Set Translate Stiffness = 0
  4. Set Rotate Stiffness = 1

He should now be using his hip to balance. Tune the group Pose Stiffness for more or less rigidity in the pose.

Hey here’s with damp 0.1, he is fine again :slight_smile:

I’ll try your suggestions now, why are we putting the “Fingers” to False though? did you mean anything ells? maybe “Legs”?

I wanted to rule out fingers causing any issues.

For example, if the fingers were self-intersecting and self-colliding, the trouble would ripple through the entire character. And generally, the more markers are in the system, the more substeps and iterations you need for it to solve; the defaults should be able to cope with fingers, but they are tuned for a body.

Substeps and iterations come at the expense of performance, hence they default to as low of a value as possible. Looks fine here though.

Ok, limit rage was already at 0, here the feet in Dynamic behaviour.
He is floting in the air like a baloon and the legs moves up? seems odd.


ok my bad, i had been messing with the gravity in the beginning.
Its now on default.
Finger enable off and dynamic behaviour on feet.

He is just standing there, chilling. not falling over.

Cool. Looks good. Remind me again what the question was? :thinking:

I want the hips to bounce a little. like the sphere i animated on the side.

I guess i can animate it myself? it just seems so odd when the arms everything ells is moving so nicely but the hips seems to be allmost stuck in space.

Are the legs colliding with the hips? That could cause the hips to stop and not move past the legs- you could try turning collisions off on the legs and see if it’s still doing it - You could get more of a wobble feel having the pose damping low - around 0.2 gets some nice results.

Hey Jason, right now everything is in one group, could that still be the issue?
I’ll take a look later.
Next step i will try is to go back to the standard capsules and also to reset all settings to default if thats possible.
And after that i think ill just try to redo the setup.

There is very little information to work with, maybe you can record yourself changing more settings, and dropping him from various heights?

Can you replicate this? Is this what you want?

You can find the character here.

Hey, yes i can do that.
So i’m allmost there now :slight_smile:
I did a new char from a default advance skeleton setup.
Here’s the result i’m after.

Here i’ve put the hips on kinimatic (aswell as the feet) and used a partical with a goal to control the hips control translation to get a bouncy behaviour i want.


Here i have a pin on the hips, with the ik feet on Kinimatic and default values on the legs nothing happens when i push the pin down. if i put the damp and stiffness on 0 on the legs (hips, knee, ankles)
I get the result above. which is pretty close but the legs are to loose now and they start rotating in.
As soon as I add just a 0.1 on the stiffness the wont bend to the will of the hips and damping does nothing for me.

any ideas?

Even 0.01 on stiffness the legs refuse to bend.
I remember in the beginning you showed me an example of a char pulling like a box or something, and the input was not much, the hips and the rest of the body was bounching up and down.

What what what!? :sweat_smile: There is a particle, as in an nParticle - a second dynamics system - that you simulate and bake out, which is then driving the Translate and Rotate channels of the hip? Or is it simulating in parallel with Ragdoll? :open_mouth:

If all you want is hip motion, then all you need is the hip.

Here I’ve disabled Gravity and pinned the hip to the animation.

They appear to be bending in your videos above, not sure what you mean here. Do the upper thighs have a Pose Stiffness = 0.01 in your video above? Can you disable the pin, and set your feet to Dynamic so I can see what it looks like when it just drops to the ground like in my video?

I’m still confused about your goal; a bouncy hip isn’t related to the hip itself, but rather the legs. If the legs are standing on the ground (nothing Kinematic) then it would be the stiffness and damping of the knees and feet that determine what happens to the hip?

Haha yes, its a parallel simulation with the particle driving the raggdoll sim. Its only driving the translation on the hips.

Yeah maybe I’m thinking about it in a wrong way. I’m thinking since the hips is the only control that translates in world space its the driving force and everything ells is just reacting to the hips but in reality everything is reacting to eachother.
My expectation at first was that the hips would try to get to the control like a particle would with a goal and didn’t think about the legs effecting its motion/simulation.

I haven’t actually tried the feet not in kinematic, i assumed that you wanted that to get the feet planted on the ground hehe.
Why does that make a difference thought?
On one the leg gets simulated to have the heel pushed against ground on the other the legs get simulated getting pushed against the kinimatic ankle control right?
Either way ill try it out tonight to see what the difference is.

If nothings ells works, maybe when i have him just standing talking/walking i should just skip the legs (maybe have the feet in a separate raggdoll setup to get som overlap action the ankle toes)
And just animate the ik legs regularly since I kinda dont want them to be simulated anyway.
Then the hips could move freely like on your example above with the rest of the spine and so on reacting to it.

A third way is maybe to have the hips as its own single point setup (like in your video) and then hock up so spine/head/arms/legs gets driven by that point somehow, maybe there a way to force the hips to be master and commander with some ragdoll constraints? :smiley:

I’m honestly at a bit of a loss with this question. :sweat_smile:

Normally, a question starts with a goal.

  1. I want my character to grab this other character.
  2. I want this tail to respond to the motion of my character.
  3. I want this fish to behave like it’s under water.

I could then say…

Aha, hmm. Good question. Try setting Air Density = 20

Whereby Ragdoll would then figure out the physics behind that; what the final motion should look like.

Your question on the other hand involves telling the solver how to solve.

  1. How can I tell Ragdoll to simulate like how I animate?

And it wrecks my mind. My suggestion would be to take a step back, consider the higher level goal of what you are trying to communicate with your character, and perhaps we can find a way of passing much of the weight and physics behind that performance over to Ragdoll, such that you can focus on the performance.