Rolling Sphere inside a cone

[Adam Trachtenberg]

Sorry, but I’ve never learned the Dynamics Module. If you have MoGraph 2 I can explain how it can be done with MoDynamics.

[Robyn Rhodes]

Yes please. I do have MoGraph 2.

Danke!

Robyn

I’m only half the thing I say I am, the other half are me.

[Brian Jones]

869_spherecone.zip

Here is a very simple example. The important parts are:

– in the Solver/Main
– Energy Loss 0 (or very low)
– Integration Method doesn’t matter much here but try various kinds. Read the Help for what the Integration methods are good for.

– Solver/Details
– if the Collision Eps is too low the sphere will respond too much to the individual polys of the cone, so you either have to up the poly count (slower) or leave the Eps higher and put in a ‘proxy’ cone so it looks like it’s touching that one. (then you make the real collider cone invisible).

The settings in the Rigid Body Tags are fairly simple but the Elasticity needs to be low (but you can adjust those if you want more bounce). And the Aerodynamics needs to be very low or it will slow it down (good for cloth or terminal velocity but not here)

[Robyn Rhodes]

Thanks very much Brian. That’s awesome. I’ll have a look at the settings. I might have a couple ?s later if that’s ok?

One thing that occurred to me right of the bat, after previewing your project. Say you wanted the ball to actually roll, say you wanted to see a texture rolling as opposed to a solid colored sphere, or mirrored, in which “actual rolling” is irrelevant. How would that be achieved?

I would still be curious to see the MoDynamics solution as well.

Thanks again!

Robyn Rhodes

I’m only half the thing I say I am, the other half are me.

[Adam Trachtenberg]

Here’s a video demonstrating how to do it with Modynamics:

https://www.3danvil.com/tutorials/ball%20and%20cone_modynamics_controller/ball%20and%20cone_modynamics.html

[Robyn Rhodes]

Vielen Dank Adam. Das ist eine Spitze Erklarung!

Robyn Rhodes

I’m only half the thing I say I am, the other half are me.

[Brian Jones]

I like the MoDynamics solution myself, I don’t have it though so just for completeness here’s a set of 3 trials.
The original with some rotation added to the Start settings – it doesn’t last long.
Then two new ones, another Dynamics solution but manipulating the Rotational Mass of the sphere and the Static and Dynamic friction setting of the sphere and the cone (and plane) – touchy stuff to get the settings right.
And finally a Clothilde solution – the rotation comes free it does not have to be set up at all but the sim seems to have a “speed limit”…

874_sphereconetrials.zip

[Robyn Rhodes]

Wow, thank you for all this.

Robyn Rhodes

I’m only half the thing I say I am, the other half are me.