The rtabmap graph changes position after a while

[breezy]

It seems like the graph can change its position when new loop closures are detected. I mapped an huge place and I want to be able to save some poses on the map frame for when necessary but since the graph changes those poses lose their meaning over time. Is there a way to attach poses to the graph so that when it changes the pose saved is still meaningful?

I know that if I labeled some node I could get it's pose and it would be the pose I want even if the graph changes, but what about some pose not in the graph?

[matlabbe]

Hi,

To do that, we would need to attach a new pose to the closest one on the graph. There is no built-in mechanism to add random poses to the graph. One way to do this would be to use landmark input of rtabmap_ros (called "tag_detections" of type apriltag_ros::AprilTagDetectionArray). Publishing the pose as a landmark relative to current pose of the robot would add it to the graph. Make sure to set an ID always different.

To add a pose anywhere in the graph, it is not possible, only labeling could be used on actual nodes in the graph.

cheers,
Mathieu