Phoenix FD 4.1 Active Bodies, Submerging, Buoyancy and Forces

[ThomasHorsley]

Hi,

I recently started exploring the Active Bodies feature in Phoenix FD 4.1 and have some questions - if you can answer any of them I'd really appreciate it.
Initially I'm testing using basic geometry / primitives to get a better understanding of the workflow - and hope to progress to more creative stuff once I'm clear on the workflow options at present.

Here is my first video (simple explanation of the setup is in the vimeo link)

https://vimeo.com/403272609

1 - Is there a way of preventing objects from falling out of the simulator?

2 - Can any of the Phoenix FD forces or 3ds Max forces be used on the Active bodies?

I've tried dropping various objects into the fluid to see how they behave when submerged - to explore how they pop back up to the surface again....

3 - This seems to work ok for spheres, but should it work on all geometry? - I'm finding that the objects often sink and get stuck to the ground plane.

Is the current 'best' workflow to pre-animate the geometry (to allow whatever control you want) and then to run the sim whilst playing with the 'Original Animation Influence' parameter ?

I realise that Active Bodies are being developed but just want to get a better idea of the current features.

Any advice much appreciated.

[georgi.zhekov]

Hey,

Currently preventing the bodies from escaping the simulator boundaries, the Forces affecting active bodies and Shape-dependent buoyancy are still in the to do list.

If an object is with neutral buoyancy, its shape will definitely influence whether it gets stuck to the ground due to friction.

Certainly - using the Original Animation Influence will give you more predictable results compared to leaving everything to the fluid force.

There is still a lot more we have in mind for the Active Bodies and it's something we're constantly improving so I hope that soon there will some news in this regard.

Cheers,

[georgi.zhekov]

We're always open for suggestions - so if you do have anything in mind, please do share and we'll see what we can do about it.

Thank you!

[ThomasHorsley]

Thanks for the quick reply Georgi - I really appreciate that.

I'll have another play with this and post another video so you can see some of the issues I was finding when submerging objects - and them sticking to the ground plane even with a low density set to 250.

My current top request for a future feature (other than Active Bodies reacting to each other which I've heard you're working on) - is to allow collisions with the simulator grid edge.

Maybe a global check box within the Active Bodies Solver, with an adjustable falloff spinner, so that you can dampen the impact - so the Active body objects could be slowed down as they approach the grid edge.
Friction and Elasticity settings of the simulator grid edge would be useful here too.

Override settings for these collisions within PhoenixFD Per-Node Properties would be great.

Forces:

Ideally, allow Active Bodies to be influenced by the existing Phoenix FD forces....(especially Plain Force and Follow Path), add if possible ! add an 'Include / Exclude' list of Active Bodies to their dialogue box.

A 'Keep Apart Force' for Active Bodies - similar to Max's 'Keep Apart Operator' would be great.

I'm sure you're super busy so thanks for taking the time to read this.

Thanks again!

[Svetlin.Nikolov]

Hey, thanks a ton for the feedback!

Just a note - if possible, please send over a scene reproducing the issue, so we'd know that after we've made changes, it has really changed for you as well, and not just on our setups that try to replicate the exact same conditions as yours This would prevent any misunderstanding and reduce back and forth.

Cheers!

[ThomasHorsley]

Thanks Svetlin.

I've just emailed a scene to support along with an explanation of what I'm trying to achieve.
Any help much appreciated.