Closed bairuofei closed 1 year ago
All frame-handling is done via topic /tf, if you enable tf in rqt_graph you will see that the mapper is connected via tf as well.
The mapper publishes the transform map->odom, so that the odometry frame slowly moves away from the origin, this is the expected behavior. (This is the correction of the odometry, which is calculated from the underlying SLAM)
You can use "rosrun tf view_frames" to generate a PDF with all frame information in the system.
That's right, thank you for the explanation. The problem is really confusing and I also encounter a similar question here. Could you please check whether the following statements are right?
Am I right? Thank you for your time!
PS: As a side note about 1: this is only true if you start the mapping and the robot directly, that is the odometry starts at origin. If the robot has already moved around before you start the mapping, then map and odom will not be aligned but set in such a way, that the robot is placed at the map origin. So the actual fact is: At start, robot and map are always identical.
Hi, when running nav2d for navigation, I find it is difficult to understand how frame_id in Stage and in nav2d_karto are related.
It seems that in rviz, the frame "odom" and "map" is closer each other, and changes slightly as SLAM operates. After checking the rqt_graph, I find the /Mapper node only subscribe the topic "base_scan" from the /Stage node. It seems there is no direct relationship between the two frame "odom" (in Stage) and "map" (in Karto SLAM). May I know at the very beginning how these two frames are related to each other?