Xiaojun,

The warning you're seeing means that something is going wrong in the laser
filters that are being applied to the tilt laser. There are a number of
different filters applied in the pr2_navigation_perception package and
you'll probably want to check the output of each to see what's going on. Off
the top of my head:

tilt_scan->tilt_scan_shadow_filtered (shadow filtering)
tilt_scan_shadow_filtered->tilt_scan_filtered (filtering based on the URDF
of the robot, in its default configuration will not work for a robot that is
not the PR2, this is probably where things are going wrong)
tilt_scan_filtered->ground_object_cloud (filtering out of obstacles that lie
on the ground)

Also, using the pr2_2dnav application on a robot that is not the PR2
probably wont work, though the components of the application can give you
insight on how to structure a similar one. I'd suggest taking a look at how
the application works and creating a similar one for your robot that has the
necessary changes. There's a tutorial on this here:
http://www.ros.org/wiki/navigation/Tutorials/RobotSetup

Hope this helps,

Eitan


On Mon, Oct 18, 2010 at 12:51 AM, clarkwu <wu.xiaojun@gmail.com> wrote:

>
> Still no any clue ... anybody?
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