[ROS Q&A] 049 - How to navigate while avoiding obstacles

More ROS Learning Resources: goo.gl/DuTPtK
Q: How to navigate while avoiding obstacles?
Original question here: answers.ros.or...
A: In order to do navigation using a laser for localization and obstacle avoidance, you need to do first a map of the environment you want to move through. For that you need to use the gmapping package. Launch the gmapping package, and then move the robot around using the keyboard or joystick so it can build the map.
Once the map is done, you need to save it using the following command:
rosrun map_server map_saver -f name_of_map
Then you are ready to use that map for localization and sending the robot to different locations in the map, while avoiding obstacles. Kill the gmapping node and launch now the localization package (the amcl). Together with the amcl you need to launch the map_server (to use the map you created on the previous step) and the move_base (to make the robot move around while avoiding obstacles).
RELATED LINKS:
* ROS Development Studio: rds.theconstructsim.com
* Robot Ignite Academy: www.robotigniteacademy.com
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[@abderrahmanesebaa7638]

Hello, thank you so much for the tutorials. they are very helpful. I have a question that I hope you can answer. How can I give the robot a destination point to go to using code instead of rviz gui ? Is there a specific message type for the coordinates that I should publish in a specific topic so that the robot can use these packages to get there ?

[@techxplorerxxx]

what if a new obstacle is added to the map while moving towards the goal??Can we avoid that obstacle and move to the nav goal?

[@kartikpujar4527]

what if the obstacle was in the environment and not in the map created using gmapping package. how to avoid obstacles in this scenario.

[@moazalhady7895]

thank you very much it was helpful video but how can i avoid obstacles without a creating a map ?????

[@krishnachaitanyadon]

You gotta run the localization node and set the 2D nav point in rviz. It should automatically avoid obstacles. AFAIK.

[@SimbawaveEDI]

thanks for showing me about how easy to use ros and gmapping, rbase, and localization. previously i didn't get it all.
at least now i'm confident to build my own bot using ros.
just wondering, if the map is created by 1 bot, and later the map is saved as 2 files, how if i copy those 2 files map and paste those files to other robot?
will the next robot have the same map like the first robot?

[@TheConstruct]

Yes you can do that and then the second robot will be able to navigate using the first robot map.

[@SimbawaveEDI]

wow... thanks for this very fast reply. this is very motivating me

[@kushanav]

hi , thank you very much for the tutorial! I am trying to add a new RobotModel and LaserScan but cant seem to locate the add remove buttons in the Rviz editor in your remote ROS env. Can you please help?

[@TheConstruct]

Do a double click on the title bar of Rviz. You will see then that the Rviz accommodates to occupy the whole screen and shows all the buttons you mention. Let us know if that works for you