Re: Demo hector_mapping

Posted by matlabbe on
URL: http://official-rtab-map-forum.206.s1.nabble.com/Demo-hector-mapping-tp5009p5011.html

Hi,

The parameters have been updated in the demo_hector_mapping.launch file. What you see is a wrong loop closure accepted because the covariances set in hector's odometry are not compatible with rtabmap. Without updating to latest rtabmap_ros version, you can add those lines under rtabmap node:

<!-- As hector doesn't provide compatible covariance in the odometry topic, don't use the topic and fix the covariance -->
<param if="$(arg hector)" name="odom_frame_id"            type="string" value="hector_map"/>
<param if="$(arg hector)" name="odom_tf_linear_variance"  type="double" value="0.0005"/>
<param if="$(arg hector)" name="odom_tf_angular_variance" type="double" value="0.0005"/>

Loop closures causing such deformation in the graph will be rejected.

EDIT
I was able to reproduce the deformation with the demo_mapping.bag. I updated rtabmap to reject loop closures also causing large wrong rotations in the graph (checking only wrong translations seems not enough in some cases like this one). See https://github.com/introlab/rtabmap/commit/829f05e2fba377f0c2516e0619aa7ecf28814569

cheers,
Mathieu