Real-Time Physics Simulation Forum

While waiting for the featherstone constraint solver, does anyone have any advice on how to minimize the amount that Bullet constraints 'break' when under force -- in particular, I'm referring to constraints that are attached together in a series (for example an articulated robot arm or robot walker)?

Does anyone have advice on creating articulated bodies? I'm building creatures that are supported by articulated limbs. Limbs therefore support -- in part -- a lot more mass than they themselves contain. I'm using btGeneric6DofConstraints and btRotationalLimitMotors. The constraints get violated ver...

Hi everyone, I have a question about simulating dominoes. When I set up a very long line of dominoes, once everything falls, I'm afraid I end up with a massive island where every domino is connected to every other one. Is there any standard methodology to break these into smaller islands, especially...

Wow, Pico, thank you so much! That was the problem. My code now appears to be stable on both Linux and Windows with 2.75 rc 3.

Out of curiosity, do you know why removeCollisionObject led to a heap corruption?

Thanks again, that really helped out!

Hi, I recently upgraded to 2.75. With beta1, rc3 and the current version in the repository (r1695), I have had errors with the heap getting corrupted on machines running both Windows and Linux. With 2.73 and 2.74, I haven't had any errors and the code is very stable. Does anyone know of something th...

Looking great... can't wait for the reintroduction of split impulse.

Thanks!

Hi,

Thanks for the response.

You're right. I checked 2.73 sp1 for stability, but I didn't check for the scenarios where split impulse is needed by my application.

Is there any way to have overlapping objects not carry momentum after they separate (besides using split impulse)?

Thanks again.

2.73 SP1 fixes this problem.

Thanks!

Hello, I've been having some problems with split impulse and stacking objects. I just downloaded 2.73 and ran through the demos featured in "AllDemos". With the split impulse box set to true, things seem to work fine. However, when I modify the demos to use split impulse, the simulation be...

Split impulse is a great feature. If you have two objects that overlap, without split impulse, the objects can fly off in different directions (due to the force of the spring used to separate them). With split impulse, once the objects are separated, they don't carry any of the momentum caused by th...

I found the source of the problem. The instabilities I'm seeing are caused by splitImpulse. If I set m_dynamicsWorld->getSolverInfo().m_splitImpulse to "true", that causes objects to interpenetrate and act "mushy". As a demonstration, I modified GimpactTestDemo so that it now has...

Ah... OK. That makes sense. In my project, I removed libGIMPACT from the libs folder and the link to it in the makefile. [Update] When I run it now, I'm getting the collision detection errors I mentioned in my first post. Trimesh objects are really interpenetrating each other. It reminds me of the b...

I am facing a similar issue. Although, with my project, objects fall from the sky and I would like the user to be able to rotate the objects as they fall. Once the objects collide with the ground or another object, they are then out of the user's control. Is the best way to do this by applying a rot...

Hi, I have been using Bullet with Gimpact for collision detection. Up until recently, things have worked really well. But now the version of Bullet in the repository (1422) no longer builds the GIMPACT library (i.e. libGIMPACT.lib or libGIMPACT.a). I tried this on two different machines under both W...

Thanks!

I was having this problem, too, but was having a hard time isolating where it was coming from.