[Pyode-user] collision woes

[Marc K. <mki...@ga...>]

Hi,

Extremely sorry if this is a repeat, but I think the first email didn't go
through.

I've been trying to make a simple robot simulator which includes
collisions.  I'm getting weird
behavior though and wondered if I'm just making a dumb mistake.  I want some
objects that are
fixed in the environment.  From other examples and from archived questions
on the list it seems like
the best way to do this is using geometry objects that are not associated
with a body.  The only
collision that works so far is if I collide with the floor plane that is
defined as a fixed geometry.
I've attached my file that uses vpython for visualization and I had the
following questions if anyone
is willing:

1)If I set a tall square in place, different sizes will result in collisions
while smaller sizes do not, why?
(Try changing width and length of square to 0.1 in line 56 of .py file to
reproduce this)
Also, if I change the bounciness in the collision callback function (line
28), it seems to have no effect
on the collision, why?

2)I can place a geometry object that is a capped cylinder in the environment
but how do I orient it?  I tried
setting the rotation, but still couldn't get a collision to occur.  Change
"OBSTACLE = 2" on line 9 to see this.

3)If I want forces from the collision, it seems that I have to have the
obstacle be associated with a body
as well, is that true?  If so, what kind of hinge or connection should I
use?  I tried a fixed joint to the
environment but that also did weird things.

Any help on any one of the questions would be very much appreciated.  Thanks
for your time.

Sincerely,

Marc Killpack
Healthcare Robotics Lab - Georgia Tech