2D occupancy grid from Rtabmap and navigation

[Aman Saini]

Hello
We tried implementing Rtabmap for autonomous navigation for leo rover but we were facing some issues. We launched these files in sequence:

roslaunch leo_erc_gazebo leo_marsyard.launch
roslaunch leo_erc_viz rviz.launch
rosrun teleop_twist_keyboard teleop_twist_keyboard.py

roslaunch rtabmap_ros rtabmap.launch \
   rgb_topic:=/zed2/left/image_rect_color \
   camera_info_topic:=/zed2/left/camera_info \
   depth_topic:=/zed2/depth/depth_registered \
   frame_id:=base_link \
   imu_topic:=/zed2/imu/data \
   wait_imu_to_init:=true \
   args:="-d"

We tried for the loop closure and obtained the following:






We need to implement move base for autonomously navigating the rover for which we need 2D occupancy grid which we are able to see in rviz. But we are not able to save the 2D occupancy grid and also not able to understand how to publish on /cmd_vel topic after creating the map.

Please help here


Also we are able to visualise our 3D point cloud on rtabmap data base viewer using command rtabmap-databaseViewer ~/.ros/rtabmap.db but don't know how to use data saved on database


We found the following resource on ros wiki but we are not able to understand how to implement it on our rover.
http://wiki.ros.org/rtabmap_ros/Tutorials/MappingAndNavigationOnTurtlebot
 
We would be highly obliged for your help.
Thanks

[matlabbe]

Hi,

just making a crossref to this similar post: http://official-rtab-map-forum.206.s1.nabble.com/Autonomous-off-road-navigation-td7396.html

rtabmap will provide the global occupancy grid for move_base under /rtabmap/grid_map topic, as shown in this tutorial: http://wiki.ros.org/rtabmap_ros/Tutorials/MappingAndNavigationOnTurtlebot

It also provides TF map->odom->base_link in your example.

Afterwards it is more a move_base configuration issue (see navigation page for help). Navigation can be done while creating the map if you want. If you want to do a localization phase after the mapping phase, you may launch rtabmap a second time with:

roslaunch rtabmap_ros rtabmap.launch \
   rgb_topic:=/zed2/left/image_rect_color \
   camera_info_topic:=/zed2/left/camera_info \
   depth_topic:=/zed2/depth/depth_registered \
   frame_id:=base_link \
   imu_topic:=/zed2/imu/data \
   wait_imu_to_init:=true \
   localization:=true

The occupancy grid should be published.

cheers,
Mathieu