Re: [Playerstage-users] AMCL's "laser_map_negate" option

[Brian G. <ge...@ai...>]

On Fri, 29 Oct 2004, Mark K. Kim wrote:

> The AMCL driver's laser_map_negate option is a bit confusing.  Black
> pixels are "occupied" and white pixels are "empty" according to the
> documentation. "Occupied" means it's occupied by solid objects therefore
> the robot cannot occupy that same space, and "empty" means there's no
> solid object there so the robot may occupy that space, right?  It's hard
> to tell from the behavior of the AMCL driver because it seems to locate
> the robot either way (or doesn't locate it at all either way.)

The laser_map_negate option is to facilitate the use of Stage bitmaps with
the amcl driver.  Stage uses black to represent free space and non-black
to represent obstacles.  The amcl driver has the opposite semantics, so
if you want to use the same bitmap for localization, you have to either
invert it yourself (e.g., using Gimp), or use the laser_map_negate option.

As to the question of how to keep amcl from locating the robot in an
obstacle, I defer to Andrew.

         brian.

-- 
Brian P. Gerkey                    ge...@ai...
Stanford AI Lab                    http://ai.stanford.edu/~gerkey