Cineversity

Hi,

I have a hose that will interact and collide with another object.
My main approach is the spline dynamics (as it is fast) and soft body (later)

Spline dynamics

The problem with spline dynamics is it collides exactly with the spline. There is no “collision radius” that I know of. (Or is there?) So when the spline is with a Sweep Nurbs to form the hose, it inevitable collides.

Previously, my workaround is to create a specific hair/spline collider object that is larger than the original object. Sure it works but this time, I need the original object to be also a collider object. As the collider object is a deforming character.

So back to the question, is there a way to Increase Collision Radius for the Spline Dynamics?

Soft Body
A bit unstable (i.e. it explodes).

You can see my attempts in this file:
https://www.dropbox.com/s/ih111cem2l3m5p2/c4d099_hose_spline_dynamics.c4d?dl=0

Thank you for looking at the problem.

P.S. I checked some previous threads and it seemed like a hopeless case. However, I’m still looking for a solution. Thank you.

https://www.cineversity.com/forums/viewthread/2370/
https://www.cineversity.com/forums/viewthread/1248/
https://www.cineversity.com/forums/viewthread/1103/

Hi bentraje,

You certainly should know this presentation:
https://www.cineversity.com/vidplaytut/siggraph_2016_rewind_-_chris_schmidt_creating_advanced_controllable_dynamic

The Spline Dynamics has a Radius option, and it works only where the vertices are. With just a few vertices and set to B-Spline (points are mostly not where the Spline is), you will have trouble.

You need to get familiar with the Dynamic settings as well, Attribute Manager> Project Settings> Dynamics> Expert. The Project Scale should be also fit the size of the object. Since this was indeed only a test file/sketch, here is a little quick fix:
https://www.amazon.com/clouddrive/share/pr4weaobYHnqLDcKqwHEwGi3XDFaLLTsCRoeFDSf7d3

https://help.maxon.net/us/#DYNWORLDOBJECT-WORLD_GROUP_EXPERT

All the best

Hi Dr. Sassi.

Sorry for missing out such an obvious parameter.
I was kinda stuck with this kind of radius (see attached).

Anyhow, your solution works as expected.

Thank you!

Yes, the Collider has one as well, like it has a Bounce and Friction value.

Think of all these values like when and how they get evaluated. It is, after all, just a simulation. It is chopped into short fragments of time. Evaluated only as often as set up, otherwise, it would be not possible to calculate anything in dynamics. Similar to light (GI), which is never a natural representation nor physically correct. No computer anyone typically uses for any 3D visualization has the power to come even close to real world setups. Light bounces so often it would take years to render one frame. It is after all, and in any app, just a try to convince the eye to get it right.
So, we need to know the few parameters and how they interact with each other to get as close as possible, in terms of results, not in terms of accurately simulated the steps between.

As a side note, often, it is better to animate manually, as we keep complete control about the visuals in that way, and it is usually much faster (CPU wise). To just take short-cuts with dynamics might not always be the best idea.

All the best

P.S.: just to be more complete, this option should be noted as it can be perhaps used as a base for joints.
https://www.cineversity.com/vidplaytut/cv-dynamic_connector_promo