Search found 53 matches

by KenB
Fri Aug 24, 2012 1:05 pm
Forum: Links, Papers, Libraries, Demos, Movies, Comparisons
Topic: New research on real-time deformable body dynamics (FEM).
Replies: 28
Views: 27546

Re: New research on real-time deformable body dynamics (FEM)

Hmm, I don't find a link to a paper. What am I missing? I also just wanted to comment about PGS. It was previously in this thread stated that PGS provides smooth convergence with improving results for each iteration. There is no guarantee for this. PGS can be noisy and cyclic, and also completely st...
by KenB
Mon May 07, 2012 9:03 pm
Forum: Research and development discussion about Collision Detection and Physics Simulation
Topic: Help picking which rigid body library to use
Replies: 1
Views: 4147

Re: Help picking which rigid body library to use

AGX Multiphysics has the functionality you need. In particular, if your system is stiff (e.g. high tension in the wires and/or large mass ratios), then I doubt that the game engines will be of much use. They can deal with ratios of perhaps 1:50 while AGX can handle 1:1e9 in such cases, with retained...
by KenB
Fri Feb 18, 2011 11:59 pm
Forum: Research and development discussion about Collision Detection and Physics Simulation
Topic: newton is open source now!
Replies: 5
Views: 7670

Re: newton is open source now!

http://newtondynamics.com/forum/viewtopic.php?f=9&p=45765#p45765 newton got released under the same license as bullet! :) i think it's an interesting alternative to bullet. similar features but force based instead of impulse based. what do you think? Given that both use discrete time, the differenc...
by KenB
Wed Dec 22, 2010 9:53 pm
Forum: Links, Papers, Libraries, Demos, Movies, Comparisons
Topic: Release of AGX, and some new videos and stuff from Algoryx
Replies: 4
Views: 6278

Release of AGX, and some new videos and stuff from Algoryx

Hi all, We have an updated website and quite a few new videos too, including constraint fluid simulations on GPU, wires and some really nice simulator videos from some of our clients. The fluid model is quite nifty and something I started wrestling with almost five years ago. It just got accepted fo...
by KenB
Wed Oct 28, 2009 11:44 pm
Forum: Research and development discussion about Collision Detection and Physics Simulation
Topic: Contact handling, bullet method or Bender method??
Replies: 16
Views: 3799

Re: Contact handling, bullet method or Bender method??

I am curious about the difference or likeness of "Sequential impulses" and projected Gauss-Seidel iterations. I really can't see any difference. "Sequential impulses" is really just an attempt to give meaning to the one-by-one equation approachs of the Gauss-Seidel method, which happens to result in...
by KenB
Wed Oct 28, 2009 12:01 pm
Forum: Research and development discussion about Collision Detection and Physics Simulation
Topic: Projected Conjugate Gradient methods for solving LCP's
Replies: 5
Views: 3307

Projected Conjugate Gradient methods for solving LCP's

Hi, We're digging deep into CG-methods for solving LCP's, e.g. contact problems. Anyone know of any recent references about this? If I remember correctly, someone implemented projected CG in ODE. Who did this, what was the result and has any of you tried it? (sorry for asking about ODE here, but my ...
by KenB
Sat Oct 17, 2009 4:09 pm
Forum: Links, Papers, Libraries, Demos, Movies, Comparisons
Topic: Algodoo Physics Educational Software by Algoryx Simulation
Replies: 9
Views: 11737

Re: Algodoo Physics Educational Software by Algoryx Simulation

I rarely login here, so sorry for not responding quickly. The Jacobian projects the generalized coordinate, so Gq is simply the constraint error. This is valid only for linear homogeneous constraints. For the general form, for other types of constraints, refer to Claude's thesis. Baumgarte comes fro...
by KenB
Mon Aug 31, 2009 11:40 pm
Forum: Links, Papers, Libraries, Demos, Movies, Comparisons
Topic: Algodoo Physics Educational Software by Algoryx Simulation
Replies: 9
Views: 11737

Re: Algodoo Physics Educational Software by Algoryx Simulation

Speaking of Algodoo, we have actually released it now!

Check it out at: http://www.algodoo.com/

We think it is totally cool :-)
by KenB
Mon Aug 31, 2009 11:39 pm
Forum: Links, Papers, Libraries, Demos, Movies, Comparisons
Topic: Algodoo Physics Educational Software by Algoryx Simulation
Replies: 9
Views: 11737

Re: Algodoo Physics Educational Software by Algoryx Simulation

Is there any chance of a simple explanation of "variational methods"? So far I've read the thesis twice and have yet to understand it well enough to implement.. What it means is that you start from a Lagrangian formulation and you discretize this Lagrangian and then apply a discrete variational (le...
by KenB
Thu Mar 26, 2009 6:44 pm
Forum: Links, Papers, Libraries, Demos, Movies, Comparisons
Topic: Algodoo Physics Educational Software by Algoryx Simulation
Replies: 9
Views: 11737

Re: Algodoo Physics Educational Software by Algoryx Simulation

A new version is out under the name "Algodoo - Phun Edition". It is free for
personal and non-commercial use.
See http://www.phunland.com/

The full product will be released in April. It contains some very nifty features including a really cool fluid simulation method.
by KenB
Sat Jan 17, 2009 3:59 pm
Forum: Links, Papers, Libraries, Demos, Movies, Comparisons
Topic: Algodoo Physics Educational Software by Algoryx Simulation
Replies: 9
Views: 11737

Algodoo Physics Educational Software by Algoryx Simulation

Yo folks! Some of you might know about the Phun 2D Physics Sandbox. We have developed a branch called Algodoo, specialized for Physics education and optimized it for the Intel-powered classmate PC. The combination of the touch screen with pen input and the accelerometer is totally awesome. We feared...
by KenB
Fri Aug 29, 2008 3:59 pm
Forum: Links, Papers, Libraries, Demos, Movies, Comparisons
Topic: Physics for Phun
Replies: 9
Views: 7989

Re: Physics for Phun

There's a new website for Phun: http://www.phunland.com/
Phun itself has also been substantially updated since the last post here, and new versions later this fall/winter will have some really cool things, never seen before...
by KenB
Fri Aug 29, 2008 3:54 pm
Forum: Research and development discussion about Collision Detection and Physics Simulation
Topic: Who invented Islands?
Replies: 3
Views: 4893

Re: Who invented Islands?

Hi guys, looking for the paper that introduced the concept of islands or explains them in enough depth to act as a reference. so far I haven't had much joy :/ Slow response on an old thread here, but maybe it is of interest to someone... You can also look for splitting and blocking methods, and per...
by KenB
Fri Aug 29, 2008 3:47 pm
Forum: Links, Papers, Libraries, Demos, Movies, Comparisons
Topic: PhD thesis on numerical methods for rigid bodies
Replies: 14
Views: 13844

Re: PhD thesis on numerical methods for rigid bodies

I'm interested in using the quaternion-based constraints that Claude outlines in his dissertation. Some of it is a bit confusing (he defines an attachment frame twice, etc). And some of the details are spread across the chapters, tucked away in long chains of proofs. Does anyone on this forum have ...
by KenB
Fri May 30, 2008 6:37 pm
Forum: Research and development discussion about Collision Detection and Physics Simulation
Topic: A new PGS solver
Replies: 19
Views: 7857

Re: A new PGS solver

Yes, hybrid solvers is the way to go, and PGS/Direct blocking is very efficient for many problems. I suppose this paper could be of interest. "A Parallel Block Iterative Method for Interactive Contacting Rigid Multibody Simulations on Multicore PCs" by Claude Lacoursière, Umeå university. http://www...