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Problems with laser scan

asked 2011-08-11 17:26:04 -0500

PKG gravatar image

updated 2011-08-11 17:36:58 -0500

I'm running hokuyo node and move_base on my robot, and found 2 issues in the operation:

(1) Obstacles seen when there are none around: Laser scan showed a long line comprising an obstacle when there was clearly none.

(2) Despite seeing obstacles close by, move_base collides with them. I'm sending scans in the /odom reference frame and using an identity transform for localization. I'm guessing this is an issue with robot base footprint?

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regarding the second part of your question: do you have the navigations stack up and running or are you sending commands directly to your move base?
Bram van de Klundert gravatar image Bram van de Klundert  ( 2011-08-11 21:12:32 -0500 )edit
Regarding 2) Do you mean that the frame_id of your scans is /odom? That would be an issue.
dornhege gravatar image dornhege  ( 2011-08-12 02:09:00 -0500 )edit
Should it be base_link?
PKG gravatar image PKG  ( 2011-08-12 08:08:08 -0500 )edit
It should be the link of the laser and you should have tf setup so that there is a transformation base_link->my_laser_link that is the laser's position on the robot.
dornhege gravatar image dornhege  ( 2011-08-12 08:39:09 -0500 )edit

1 Answer

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answered 2011-08-11 22:26:40 -0500

Zack gravatar image

updated 2011-08-15 16:16:54 -0500

1. Is your laser mounted on a mobile platform? If it is mounted low enough, the slight unevenness of the ground will cause the laser to tilt and the beam to be reflected off the ground. You can verify by the laser data by checking it when it is stationary.

2. check if the inflated obstacles are published correctly. if they are not, try checking the local costmap file params yaml file. make sure that the frames are correct.

global_frame: /odom

robot_base_frame: base_link

hope this helps

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Asked: 2011-08-11 17:26:04 -0500

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Last updated: Aug 15 '11