Search found 197 matches
- Thu Sep 24, 2009 7:09 pm
- Forum: Research and development discussion about Collision Detection and Physics Simulation
- Topic: How to deal with Rigid and softbody interaction
- Replies: 21
- Views: 16009
Re: How to deal with Rigid and softbody interaction
Thanks raigan2 : Could you tell me in which GDC paper of David wu that contains what you said abstract "Degrees of Freedom" interface ,or should I read all his paper? I'm sorry for being so vague, here are the specific papers: http://pseudointeractive.com/files/CelDamagePhysicsGDC2002.ppt...
- Wed Sep 23, 2009 5:19 pm
- Forum: Research and development discussion about Collision Detection and Physics Simulation
- Topic: How to deal with Rigid and softbody interaction
- Replies: 21
- Views: 16009
Re: How to deal with Rigid and softbody interaction
One the topic of combining rigid+soft simulation, you might also be interested in David Wu's method, which is to have constraints work with an abstract "Degrees of Freedom" interface so as to be agnostic about the specific type of bodies being constrained: http://pseudointeractive.com/tech...
- Sat Sep 19, 2009 11:26 pm
- Forum: Research and development discussion about Collision Detection and Physics Simulation
- Topic: Stable box stacking
- Replies: 18
- Views: 20090
Re: Stable box stacking
It also make me wonder, how Box2D handle this case? Doesn't it have to spend more time when dealing with complex shapes? It uses SAT+clipping to generate one or two contact points (for a pair of convex colliding shapes), and solve the contacts together: http://www.gphysics.com/archives/38 The main ...
- Sat Sep 19, 2009 6:47 pm
- Forum: Research and development discussion about Collision Detection and Physics Simulation
- Topic: Stable box stacking
- Replies: 18
- Views: 20090
Re: Stable box stacking
Potential contacts here means those who would penetrate in the next time step if we don't do anything This is something I may not properly understand; our current implementation simply extrapolates object states and generates "potential collision" constraints between pairs of features who...
- Sat Sep 19, 2009 3:54 pm
- Forum: Research and development discussion about Collision Detection and Physics Simulation
- Topic: Stable box stacking
- Replies: 18
- Views: 20090
Re: Stable box stacking
About your comments on large number of contacts : In general, ST method cd results in more contacts than usual as you mentioned, but most of those contacts have positive distances (not penetration) and if you careful enough , you can solve them quickly in the solver. Think of them as many "eas...
- Sat Sep 19, 2009 3:46 pm
- Forum: Research and development discussion about Collision Detection and Physics Simulation
- Topic: Stable box stacking
- Replies: 18
- Views: 20090
Re: Stable box stacking
[uh, please see following comment]
- Sat Sep 19, 2009 2:01 pm
- Forum: Research and development discussion about Collision Detection and Physics Simulation
- Topic: Stable box stacking
- Replies: 18
- Views: 20090
Re: Stable box stacking
I'm quite interested in this method, as we're currently doing something similar to Stewart-Trinkle for collision (i.e potential future collisions are solved during the current step), and it's a bottleneck -- for instance when you have e.g a pile of octagons, you end up solving a lot of useless const...
- Thu Sep 17, 2009 2:16 pm
- Forum: Research and development discussion about Collision Detection and Physics Simulation
- Topic: Wind Simulation with Biped
- Replies: 1
- Views: 2736
Re: Wind Simulation with Biped
I don't have any experience in this field, but I would assume that you might start with a regular balancing controller (i.e balancing under the force of gravity) and extend it so that when calculating the center-of-pressure/zero-moment-point/etc., rather than projecting straight down (along the dire...
- Thu Sep 10, 2009 8:41 pm
- Forum: Research and development discussion about Collision Detection and Physics Simulation
- Topic: Finite Elements Method: are there proble,s with stability?
- Replies: 57
- Views: 79069
Re: Finite Elements Method: are there proble,s with stability?
This paper has a few details on how DMM works, it might be worth checking out: http://www.cs.berkeley.edu/b-cam/Papers ... -2009-RTD/
- Tue Sep 01, 2009 7:38 pm
- Forum: Research and development discussion about Collision Detection and Physics Simulation
- Topic: Position Based Dynamics (PBD)
- Replies: 6
- Views: 9544
Re: Position Based Dynamics (PBD)
Since the solver is updating position, why also constrain linear velocity? Why not update linear velocity as show on line 13 in the algorithm presented in section 3.1, and also do the same for angular velocity once you solve for the change in orientation? I simply meant that if you wish to, you can...
- Tue Sep 01, 2009 7:05 pm
- Forum: Links, Papers, Libraries, Demos, Movies, Comparisons
- Topic: Algodoo Physics Educational Software by Algoryx Simulation
- Replies: 9
- Views: 25391
Re: Algodoo Physics Educational Software by Algoryx Simulation
Hmm, not sure this was a simple explanation, but I did my best :-) Thanks for trying! Part of my problem is that I have no training in dynamics, so that when considering simulations I have to resort to simpler geometric interpretations -- i.e the state of the system is a point in a high-dimensional...
- Mon Aug 31, 2009 6:57 pm
- Forum: Research and development discussion about Collision Detection and Physics Simulation
- Topic: Position Based Dynamics (PBD)
- Replies: 6
- Views: 9544
Re: Position Based Dynamics (PBD)
We have a 2D rigid-body simulator based on Jakobsen/Muller, however each body modeled as is a pair of particles connected by a stick rather than a true 2D rigid bodies (i.e 2D position + 1D orientation). You should definitely be able to apply the same ideas (least-squares fitting of the system state...
- Fri Jul 03, 2009 2:46 pm
- Forum: Research and development discussion about Collision Detection and Physics Simulation
- Topic: Control Question
- Replies: 0
- Views: 2435
Control Question
hi, I'm trying some motorized animation, and am having problems hitting worldspace targets. I'm not sure if my problems are due to incorrect modeling of the system, incorrect control mechanisms, or incorrect expectations :) A simple example case (in 2D): imagine two rigid bodies A,B connected by a j...
- Wed Jun 10, 2009 7:18 pm
- Forum: Research and development discussion about Collision Detection and Physics Simulation
- Topic: Solving a single island across multiple cores
- Replies: 7
- Views: 6732
Re: Solving a single island across multiple cores
I'm looking forward to checking them out once I get a new graphics cardErwin Coumans wrote: Actually, if you just check out the Bullet 2.75 beta1, compile the demos, and run Gpu2dDemo or Gpu3dDemo, you can check the batches on-screen.
- Wed Jun 10, 2009 5:18 pm
- Forum: Research and development discussion about Collision Detection and Physics Simulation
- Topic: Solving a single island across multiple cores
- Replies: 7
- Views: 6732
Re: Solving a single island across multiple cores
Awesome, thanks!