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This worked for me as well, I had the same problem. Thank you!

Hello there again

I am trying to run the navigation stack with my own robot. So far i created a map, which worked fine. I followed the navigation tutorial to set up my robot. When I launch the configuration file, everything seems ok, when launching the move_base.launch file I get the warning: The origin for the sensor is at (-0.00, 0.01, 0.00) is out of map bounds. So, the costmap cannot raytrace for it.

But i think this is because I didn't set the initial pose of the robot. When I try to do this in rviz, following the tutorial on using rviz for navigation, my pose doesn't get accepted. The same thing happens to the goal pose. The arrow vanishes and nothing happens, the warning "out of bounds" persists.

When I look at my tf tree it is map->odom->base_link->laser, so this should be ok. I tried to fix this in the past days but didn't achieve anything.

Is there anything I am missing? Maybe you need more infos...

Thanks in advance!

Thank you very much for your answer. So if I understood correctly I just need to provide my pose estimated by the localization node via tf? I will try this give an update. Thanks!

Hello together

This is my first attempt at using the navigation stack. I have written my own node to localize my robot using a laser scanner and kalman fitler,the odometry is not reliable enough. The localization gives me the pose of the robot. I would now like to use move_base with my determined pose to drive to certain goals. I wouldlike, that move_base relies only on my localization, because the odometry is ot reliable enough. How can I tell the move_base node to use my own pose?

Thanks allot in advance!

---------Update-------------- After yout post I looked into AMCL and saw, that this could as well solve my problem. I have a map consisting of four landmarks and I know the starting position. The laser will register at least two of those landmarks, which is sufficient for a localization in 2D (afaik...). The problem is, that the laser will as well register allot of "noise" inside and outside the desired area (people and robots moving). But if I limit the region of interest for amcl to the area without noise, which contains all the landmarks, shouldn't it be possible to use AMCL as it is? If so, how can I limit the information provided by the topic scan to the region of interest? Can I write a node, which takes the scan informations, eliminates all unneeded scans and passes the filtered data?

P.s.(should i post this as a knew question?)

Thanks in advance

Thank you for your answer.

The table will be located in a large hall (we are participating in a mobile robot competition and are fairly new to mobile robotics, that is this is our first non virtual robot) There will be about 6 people slightly moving around the table (referee, team members and commentator) but not entering the tablearea. There will certainly be some stationary objects, but I don't know what and in which distance to the table. The primary goal is to know where the robot is and to navigate it to several predefined points on the table with a certain orientation. We know the inital pose of the robot. I noticed this drift in the first test but hoped it would not affect the application. So maybe the approach with the laser_scan_matcher isn't the best choice. I would like to not completely rely on the odometry because we are using omniwheels and should navigate to the positions as precisely as possible. But until now I couldn't think of a better solution to acomplish this task.

Hello ROS-Community

I have a question regarding localization with a laser scanner. I am planing to use a Hokuyo Laser Scanner to localize my robot. I tried the laser scan matcher package in a small room and it worked perfectly. The robot is meant to operate on a table 2x3 meters in size. On each corner there are 8x8x8 cm beacons and a large semicircle on the side which must be used for localization. The sensor will see something like the figure below.

   _                       ___________                          _
  |_|                     |           |                        |_|
                           \_________/  







   _                                                            _
  |_|                                                          |_|

Is it possible to use the laser scan matcher package on an environment with few objects to match such as the beacons above? Odometry information will be available. At the moment, the laser is not available, so I can't test it. My guess is, that the laser scan matcher package works mainly with straight lines.

Thank you in advance for your answers

Steve

Appended

Ok, thank you. I will try to limit the FOV of the laser. I thought of tracking the beacons. Since I know their initial position and the laser operates with 10 Hz I can create for each beacon a ROI and ignore the remainig scans. Then it shouldn't (theoretically) matter if there are moving objects around the table. As soon as the laser is available, I will try this. Thank you very much!