Bouncing Balls Down Stairs

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RobboUK
Posts: 6
Joined: Mon Jan 31, 2011 12:23 pm

Bouncing Balls Down Stairs

Post by RobboUK »

Hi

For a University project I am compositing bouncing balls into a scene after trying and failing with Maya's Rigid body system I was directed from another forum to this plugin and website. I built up the scene using passive bodys and then created a few active bodies for the balls, pressing play then didn't do anything. I have since created a simple scene with stairs and two balls, I managed to get the balls to interact with the stairs but at the moment it's not very accurate movement.

The balls currently move very fast, im talking about within the 200 frames the animation is done, and the balls dont really 'bounce' really just fall straight down the stairs. Does anyone know how to make a more realistic reaction of bouncing balls on stairs. When I first started this project I was inspired by the Sony Bravia TV advert of bouncing balls, http://www.youtube.com/watch?v=oP5J4W5GQ3w obviously this was done with real balls but I would really like to get this kind of movement.

So if anyone knows what sort of settings I should be changing for the overall 'bounciness' of the animation and how I could slow down the animation would be really helpful

Thanks
Paul
Johan Gidlund
Posts: 26
Joined: Mon Jun 01, 2009 2:21 pm
Location: Sweden

Re: Bouncing Balls Down Stairs

Post by Johan Gidlund »

Bounciness is typically controlled by restitution.
lulzfish
Posts: 43
Joined: Mon Jan 03, 2011 4:26 pm

Re: Bouncing Balls Down Stairs

Post by lulzfish »

To slow it down you might use a smaller step size.
RobboUK
Posts: 6
Joined: Mon Jan 31, 2011 12:23 pm

Re: Bouncing Balls Down Stairs

Post by RobboUK »

thanks johan that seems to have given me more bounce

Lulzfish, is the step size in a different place when using bullet? just because I can't access it from the usual place in the solvers menu.
RobboUK
Posts: 6
Joined: Mon Jan 31, 2011 12:23 pm

Re: Bouncing Balls Down Stairs

Post by RobboUK »

Found it Lulzfish, thanks alot man, worked a treat
frankmariusengen
Posts: 5
Joined: Thu Jan 26, 2012 2:17 pm

Re: Bouncing Balls Down Stairs

Post by frankmariusengen »

Is it normal to not be able to set the restitution heigher then 1? I cant set my restitution to more then 1 and it still settle straight away. Any solutions?
Thanks in advance.
kloplop321
Posts: 55
Joined: Sun Jan 01, 2012 7:37 pm

Re: Bouncing Balls Down Stairs

Post by kloplop321 »

Restitution is a ratio from 0 to 1 inclusively for how much is not absorbed by the impact.
A rubber ball might have a restitution of 0.98, while a bowling ball something like 0.02.
Perhaps look at the restitution of the other object you are hitting.
frankmariusengen
Posts: 5
Joined: Thu Jan 26, 2012 2:17 pm

Re: Bouncing Balls Down Stairs

Post by frankmariusengen »

Thanks kloplop321 that works perfectly. Cheers