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Friction issues with kinematic ovjects #652

Closed GoogleCodeExporter closed 9 years ago

GoogleCodeExporter commented 9 years ago 
What steps will reproduce the problem?
1. Compile the provided modified BasicDemo.cpp
2. The stack of cube does not get any velocity from the friction on the ground 
cube

What is the expected output? What do you see instead?
The stack of cube just sits still while the ground cube moves,
with bullet 2.76 the stack follows the ground cube

What version of the product are you using? On what operating system?
The latest trunk shows the bug.

Original issue reported on code.google.com by majestik...@gmail.com on 20 Sep 2012 at 3:13

Attachments:

GoogleCodeExporter commented 9 years ago 
Here are some screenshots, after a few frames and later in the sim for 2.78 and 
latest trunk

Original comment by majestik...@gmail.com on 20 Sep 2012 at 3:20

Attachments:

GoogleCodeExporter commented 9 years ago 
It is fixed in the latest shiny trunk:
http://code.google.com/p/bullet/source/detail?r=2591

(and added the rolling friction to the construction info)
Thanks a lot for the report!

Original comment by erwin.coumans on 20 Sep 2012 at 3:33

GoogleCodeExporter commented 9 years ago 
Seems like this unearthed some very bizarre behaviour ..
like the contacts have a lifespan that is too short ?

http://bulletphysics.org/Bullet/phpBB3/viewtopic.php?f=9&t=8146&start=45#p28804

Original comment by majestik...@gmail.com on 20 Sep 2012 at 4:30

GoogleCodeExporter commented 9 years ago 
Actually managed to reproduce the problem 
with the BasicDemo once again.
If you keep playing the demo, you will see some
cubes starting to freak out, either they shoot upwards
(my guess is that they start to sink into the ground
and get a big penalty force upwards), or cubes just sinking
into the ground.

And it looks like it only happens with split impulse turned on.

Cheers
Francois

Original comment by majestik...@gmail.com on 20 Sep 2012 at 5:28

Attachments:

GoogleCodeExporter commented 9 years ago 
Good find, can you check the latest trunk?

http://code.google.com/p/bullet/source/detail?r=2593
Thanks again!

Original comment by erwin.coumans on 20 Sep 2012 at 11:33

GoogleCodeExporter commented 9 years ago 
All good with this !

Thanks a lot !
Francois

Original comment by majestik...@gmail.com on 20 Sep 2012 at 9:15