Re: General questions about mapping and odometry

Posted by adr_arroyo on
URL: http://official-rtab-map-forum.206.s1.nabble.com/General-questions-about-mapping-and-odometry-tp3432p3469.html

Hi,
we are not sure of the causes of this odometry variance. We consider our odometry's covariance matrix correct (it might not be given this). The odometry of the robot is divided in: wheels encoders for traslation and IMU for rotation. It might be better to filter it with the robot_localization package as you said given this unsual drifts.
 The odom message looks like:
header:
  seq: 6065
  stamp:
    secs: 1499943999
    nsecs: 403572456
  frame_id: odom
child_frame_id: base_footprint
pose:
  pose:
    position:
      x: 0.0
      y: 0.0
      z: 0.0
    orientation:
      x: 0.0
      y: 0.0
      z: 0.000118427855769
      w: 0.999999992987
  covariance: [0.001, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.001, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 99999.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 99999.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 99999.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.001]
twist:
  twist:
    linear:
      x: 0.0
      y: 0.0
      z: 0.0
    angular:
      x: 0.0
      y: 0.0
      z: 0.0
  covariance: [0.02, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 99999.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 99999.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 99999.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 99999.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 99999.0]

About the error of the covariance in the links, it is weird that it appears but also that every time it appears its the same value. In other db ive noticed that the values are different (only ~2.0 of variance) but the same over all of this high covariances.

Cheers and thanks