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jedipottsy
04-07-2010, 09:06 PM
Hi, im having a bit of trouble getting an archimedes screw to lift a ball. I have left enough room for collisions but the sphere goes crazy. Am i doing something wrong? Im trying to make this:
http://upload.wikimedia.org/wikipedia/commons/2/22/Archimedes-screw_one-screw-threads_with-ball_3D-view_animated_small.gif

aghawa
04-07-2010, 11:56 PM
Here it goes; nCloth setup.
The standard maya rigid solver sucks GIANT d*cks. It interpenetrates, i guess because it sooooo speedy for it :banghead: .
Anyway, thank god nCloth acts great as a rigid solver.
No problems now, but your ball wont go up, but down. But that's only a "physics" related problem, maybe your spiral isn't modeled as Archimede's. Well, you'll see your stuff, but the original problem is gone ;)
Enjoy!
Aghawa

jedipottsy
04-08-2010, 12:14 PM
Here it goes; nCloth setup.
The standard maya rigid solver sucks GIANT d*cks. It interpenetrates, i guess because it sooooo speedy for it :banghead: .
Anyway, thank god nCloth acts great as a rigid solver.
No problems now, but your ball wont go up, but down. But that's only a "physics" related problem, maybe your spiral isn't modeled as Archimede's. Well, you'll see your stuff, but the original problem is gone ;)
Enjoy!
Aghawa

Thanks, Only problem is the ball deforms, ive set all the compression resistances to 200, rigidity to 20. Is there a way to turn off softbody?

aghawa
04-08-2010, 12:19 PM
Go up with "Rigidity" value. :thumbsup:

EDIT: Wait, you set rigidity to 20?? Really strange :shrug: it should be completely stiff at that value :shrug:

jedipottsy
04-08-2010, 12:58 PM
Go up with "Rigidity" value. :thumbsup:

EDIT: Wait, you set rigidity to 20?? Really strange :shrug: it should be completely stiff at that value :shrug:


tried everything, but the ball deforms when its near the poles which isnt noticable when its going up the spiral but then its rolling down it deforms and the simulation breaks.

http://www.youtube.com/watch?v=oxgEYh_ZSTA

avillabon
04-08-2010, 08:17 PM
perhaps give dynamica bullet a try? that solver for rigid bodies is impressive! Been using it for a while now..

Alex

john_homer
04-08-2010, 09:23 PM
rather than setting bend/stiffness/rigidity..

just select all the verts in the sphere and make a component to component constraint.
set the connection type to "max distance" and set the max distance high enough so every vert is connected to every other vert (ie, set it to your sphere diameter)

set the strength to 100

faster and better

.j

azshall
04-09-2010, 03:58 AM
If its just a ball .. Why not just use Maya's shitty rigid bodies? ...Yes, they're pretty jenkins when it comes to doing anything worth a shit, but simply moving a sphere shouldn't be a problem.

Try actually making as low resolution non-renderable sphere that you can get away with and parent your beauty sphere to it. Make the low res sphere the rigid body.. Should be no problem.

avillabon
04-09-2010, 07:14 PM
If its just a ball .. Why not just use Maya's shitty rigid bodies? ...Yes, they're pretty jenkins when it comes to doing anything worth a shit, but simply moving a sphere shouldn't be a problem.

Try actually making as low resolution non-renderable sphere that you can get away with and parent your beauty sphere to it. Make the low res sphere the rigid body.. Should be no problem.

Thats a very good point.. a simple sphere should not be a problem.. Try with a lower res sphere like seth suggests, should work just fine.

Alex

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