Error: Very large angular variance

Posted by kolohe113 on
URL: http://official-rtab-map-forum.206.s1.nabble.com/Error-Very-large-angular-variance-tp5194.html

Hi! I am running Rtabmap with ROS Kinetic, Ubuntu 16.04. whenever I ran Rtabmap's launch file, I got this warning:

Memory.cpp:810::addSignatureToStm() Very large angular variance (67953.453125) detected! Please fix odometry twist covariance, otherwise poor graph optimizations are expected and wrong loop closure detections creating a lot of errors in the map could be accepted.

I am using the Realsense 435 for camera topics;  Hokuyo UST-20LX for scan, and turtlebot for wheel odometry.

Here is my Rtabmap launch file:

<div style="background: #ffffff; overflow:auto;width:auto;border:solid gray;border-width:.1em .1em .1em .8em;padding:.2em .6em;"><pre style="margin: 0; line-height: 125%"><launch>
  <arg name="gui_cfg"              default="~/.ros/rtabmap_gui.ini" />
  <arg name="launch_prefix"        default=""/> 
  <arg name="output"              default="screen"/>


  <group ns="rtabmap">
        <node name="rtabmap" pkg="rtabmap_ros" type="rtabmap" output="screen" args="--delete_db_on_start">
      <param name="frame_id" type="string" value="base_link"/>

      <param name="subscribe_depth" type="bool" value="true"/>
      <param name="subscribe_scan" type="bool" value="true"/>

      <remap from="odom" to="/wheel_odom"/>
      <remap from="scan" to="/scan"/>


      <remap from="rgb/image" to="/camera/color/image_raw"/>
      <remap from="depth/image" to="/camera/aligned_depth_to_color/image_raw"/>
      <remap from="rgb/camera_info" to="/camera/color/camera_info"/>
       
      <param name="queue_size" type="int" value="10"/>

      <!-- RTAB-Map's parameters -->
      <param name="RGBD/NeighborLinkRefining" type="string" value="true"/>
      <param name="RGBD/ProximityBySpace"  type="string" value="true"/>
      <param name="RGBD/AngularUpdate"    type="string" value="0.01"/>
      <param name="RGBD/LinearUpdate"      type="string" value="0.01"/>
      <param name="RGBD/OptimizeFromGraphEnd" type="string" value="false"/>
      <param name="Reg/Force3DoF"      type="string" value="true"/> <!--same as optimizer/slam2D -->
      <param name="Reg/Strategy"          type="string" value="1"/> <!-- 1=ICP -->
      <param name="Reg/Force3DoF"          type="string" value="true"/>
      <param name="Vis/MinInliers"        type="string" value="5"/>
      <param name="Vis/InlierDistance"    type="string" value="0.1"/>
      <param name="Rtabmap/TimeThr"        type="string" value="700"/>
      <param name="Mem/RehearsalSimilarity"   type="string" value="0.45"/>
      <param name="Grid/CellSize" type="string" value="0.05"/> <!-- 5cm voxel default-->
      <param name="Kp/MaxFeatures" type="string" value="400"/>
        <param name="Optimizer/Strategy" type="string" value="0"/> <!-- 0 is TORO, Default G20-->
        <param name="RGBD/OptimizeMaxError" type="string" value="0"/> <!--When using TORO, seto to 0,otherwise set to 1-->
        <param name="Kp/DetectorStrategy" type="string" value="6"/> <!--0=SURF 1=SIFT 2=ORB 3=FAST/FREAK 4=FAST/BRIEF 5=GFTT/FREAK 6=GFTT/BRIEF(default) 7=BRISK 8=GFTT/ORB 9=KAZE-->
        <param name="RGBD/LoopClosureReextractFeatures" type="string" value="true"/> <!--extract features even if there are some already in the node-->
        <param name="Grid/FromDepth" type="string" value="false"/> <!--suppress warning (subscribe_scan=true)-->
        <param name="RGBD/ProximityPathMaxNeighbors" type="string" value="10"/> <!--suppress warning (subscribe_scan = true and Reg/Strategy=1-->
        <param name="Vis/FeatureType" type="string" value="6"/> <!--suppress warning,want to be same as KP/detectorstrategy -->
        </node>

        <!-- Visualisation RTAB-Map -->
        <node pkg="rtabmap_ros" type="rtabmapviz" name="rtabmapviz" args="-d $(arg gui_cfg)" output="$(arg output)" launch-prefix="$(arg launch_prefix)">

  <param name="subscribe_rgbd"    type="bool"   value="false"/>
  <param name="subscribe_scan"    type="bool"   value="true"/>
  <param name="subscribe_scan_cloud" type="bool"   value="false"/>
  <param name="frame_id"          type="string" value="base_link"/>
  <param name="odom_frame_id"    type="string" value=""/>
  <param name="wait_for_transform_duration" type="double"   value="0.2"/>
  <param name="queue_size"        type="int"        value="10"/>
  <param name="approx_sync"      type="bool"   value="true"/>
   



      <remap from="rgb/image" to="/camera/color/image_raw"/>
      <remap from="depth/image" to="/camera/aligned_depth_to_color/image_raw"/>
      <remap from="rgb/camera_info" to="/camera/color/camera_info"/>

 
 
  <remap from="scan"                to="/scan"/>

  <remap from="odom"                to="/wheel_odom"/>
        </node>

  <node pkg="tf" type="static_transform_publisher"  name="base_to_laser"
      args="0.0 0.0 0.3 0 0 0 /base_link /laser 100" />

  <node pkg="tf" type="static_transform_publisher"  name="base_to_cam"
    args="0.05 0.0 0.3 0.0 0 0 /base_link /camera_link 100" />

  </group>
</launch>
</pre></div>

Any help is appreciated. Thank you!