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rtabmap two odometry frames

I am trying to use Intel Realsense t265 visual odometry camera with rtabmap on turtlebot3.

So, I have wheel odometry and camera odometry. t265 camera odometry uses wheel odometry as input. So, I need only camera odometry as input for doing SLAM.

Camera odometry frame is located where is camera located on the robot, on the top and front side. Wheel odometry is located on base_footprint

For rtabmap I set frame_id to base_link and odom input topic to /t265/odom/sample. When I run rviz I see that map is building around t265odomframe and base_link is located under the map.

Where is odometry frame should be placed on the robot for rtabmap? On the base_footprint place, right?

I suppose I should create new frame on the wheel odometry place, and write a script publishing camera odometry transformed from t265odomframe under this newly created frame. And then put this topic as input for rtabmap, am I right?

Asked by june2473 on 2020-01-23 05:35:07 UTC

Comments

kindly take a look at rep-105

Asked by Choco93 on 2020-01-23 06:24:51 UTC

Answers

The frame_id you set in rtabmap should be the base frame of the robot, which seems to be base_footprint in your case. Normally, the frame inside the odom topic should be also base_footprint.

Your wheel odometry would be on base_footprint. Is /t265/odom/sample outputting in same frame than your wheel odometry? If so, you may get a TF tree like that:

/map -> /odom_realsense -> /base_footprint -> /realsense_camera

You may add the TF tree to your question to have more details.

Asked by matlabbe on 2020-02-05 17:53:52 UTC

Comments

no, /t265/odom/sample is outputting in t265_odom_frame

so, I need to make transformation of t265 odometry data from t265_odom_frame to base_footprint, right?

what about wheel odometry frame? where can I place it on that odom tree in this case?

Asked by june2473 on 2020-02-06 23:30:36 UTC

I am not aware enough to know if t265_odom_frame woudl be the correction of the wheel odometry or if it is a new frame merging visual and wheel odometry. Is there a realsense documentation about that somewhere for this feature?

Asked by matlabbe on 2020-02-20 17:14:16 UTC