Re: Best Practices for Quick Automatic Localization

Posted by dschnabel on
URL: http://official-rtab-map-forum.206.s1.nabble.com/Best-Practices-for-Quick-Automatic-Localization-tp6881p6923.html

Yes, after building rtabmap with g2o support and using Optimizer/Strategy = 1 the apriltags show up in Graph View and also under the topic /rtabmap/landmarks. Great that 'landmarkId' has been added to Info.msg. Thanks!

Interestingly, apriltags localization was already working with TORO, I just couldn't see them in database viewer. But on detection my robot was jumping to the rough location on the map even without a loop closure or proximity detection.

And I noticed that localization based on landmark detection is not very precise. In my case, driving toward an apriltag causes the robot to jump around drastically compared to when MarkerDetection is turned off. This might be because my tags are fairly small (5.5x5.5 cm) and I assume localization gets better the bigger the tags are, correct?

In my case apriltags are useful for rough location estimates, e.g. when robot starts in an unknown location. But after the initial estimate I'd rather rely on odometry. As a workaround I modified the code in rtabmap.cpp and memory.cpp to disable marker detection after the first apriltag has been detected or once we have a loop closure. This gives me smoother results.

By the way, I noticed that when I run my database through rtabmap-recovery, then all my landmarks are gone. Is that a known issue?