search

introlab / rtabmap

RTAB-Map library and standalone application
https://introlab.github.io/rtabmap
Other
2.86k stars 789 forks source link

Extract logged node covariance #701

Open eliabntt opened 3 years ago

eliabntt commented 3 years ago

Good morning, I've a quick question. Starting from a database is it possible to get a text/csv file with the covariance (linear/angular) of all nodes? I've seen there's the possibility to plot it with Memory/Odometry_variance_ang/ but cannot find a way to directly save it as log.

eliabntt commented 3 years ago

Side question, when I export poses (through rtabmap-databaseViewer -> export poses) the link covariance that I have in the log (for example in g2o) is the one optimized after LC or the raw one?

matlabbe commented 3 years ago

I think you already answered your first question. The g2o export contains raw covariance (in information matrix format). In Graph view, if you move the slider left to 0, you will export odometry poses. The slider shows the graph and each iteration step of g2o or gtsam (0 meaning no optimization). When you export poses, the current graph selected by the slider is exported (covariances are all the same (raw ones) independently of the iteration chosen).

eliabntt commented 3 years ago

aren't those link based [so information matrix of the link from node x to node y] and not node's ones [so covariance of the odometry at the time of the node addition/of the single node after the optimization]?

matlabbe commented 3 years ago

The information matrix on a neighbor link between node x and node y would be the odometry twist covariance matrix received when node y has been created.