Dynamics, make a sphere move inside a bowle.
 

Hei,

i am working with dynamics to make a roulette table. And I would like to get it to start moving on the top of my bowl and travel in circles in to the bottom. I have tried to link it up with a active and a passive rig. and start it by using initial velocity but it just makes its way to the top ov the bowl and from there out of it. of couse have i added gravety, but it dosent seem to mind it..

I need som help!!:P

PS. check out Casino movie that will be posted in march.


The yellow mark is here I want it to be, but ist heading towards the red one...

set it as a passive rigid body, and key its motion, for just two frames (or, actually, just two parts of a frame). then key it it back to being an active rigid body. that should get you more the motion you want.

question cause i've never really messed with it, but what if he were to whack it really hard into the bowl with an invisible colliding object??

I didn't realise this same question was posted in two different sections, I just thought it was a bug with the board software.

I had the same problem last night when trying to replicate it. At first I though it was 'cos I'd forgotten to reverse the normals on the bottom part which the inside of 1/2 a sphere. Now I'm not so sure if it's the order that the constraints and gravity are added, or if it's just a size/scale related thing.

In any matter, you'll find a working solution here.
Simon

heh i was wondering why he had two posts...

dynamics are fun. yes you can whack it with an invisable object but you get un predictable results unless you set it up like a pinball machine with a guiding channels and everything, thats when it gets expensive. there are settings to give it "impulse" or innitial impulse.

the trick is figuring out which direction your spitting it in and how much force your applying. you also need to take into account the requirement for gravity in the scene otherwise it will treat it like a half pipe and fly out the other side.

you also should probibly redo this scene with simpeler objects and the minimum of ridged bodies. that way you take additional variables out of the equasion it dosent even have to think about.