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Pose Covariance for swiftnav_ros rtk message

Hello all,

I am using Piski Multi RTK gps system for centimeter accurate pose information.

Below is a snapshot of a Navmsgs::Odometry message, as published by the swiftnavros package, after taking my little robot outside and driving it around, with the gps in RTK mode.

header: 
  seq: 183
  stamp: 
    secs: 1507219077
    nsecs: 699150124
  frame_id: gps
child_frame_id: ''
pose: 
  pose: 
    position: 
      x: 2.89
      y: 4.694
      z: -0.749
    orientation: 
      x: 0.0
      y: 0.0
      z: 0.0
      w: 0.0
covariance: [324000000.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 324000000.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 1296000000.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 1000.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 1000.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 1000.0]
twist: 
  twist: 
    linear: 
      x: -1.111
      y: 0.852
      z: 0.016
    angular: 
      x: 0.0
      y: 0.0
      z: 0.0
  covariance: [0.0022500000000000003, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0022500000000000003, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0046500000000000005, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 1000.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 1000.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 1000.0]
---
header: 
  seq: 184
  stamp: 
    secs: 1507219077
    nsecs: 799420749
  frame_id: gps
child_frame_id: ''
pose: 
  pose: 
    position: 
      x: 2.779
      y: 4.766
      z: -0.75
    orientation: 
      x: 0.0
      y: 0.0
      z: 0.0
      w: 0.0
covariance: [324000000.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 324000000.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 1296000000.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 1000.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 1000.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 1000.0]
twist: 
  twist: 
    linear: 
      x: -1.099
      y: 0.715
      z: -0.026
    angular: 
      x: 0.0
      y: 0.0
      z: 0.0
  covariance: [0.0022500000000000003, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0022500000000000003, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0046500000000000005, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 1000.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 1000.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 1000.0]

Please note that the covariances for x, y, and z pose are 529000000.0, 529000000.0, and 2601000000.0, respectively.

These numbers seem obsenely large, or is this normal and correct? The numbers for the twist message seem reasonable.. My piksi was definitely in RTK Mode (mode led was solid blue)

Thank you,

Jad

Asked by JadTawil on 2017-10-05 19:29:56 UTC

Comments

Please always use the Preformatted Text button (the one with 101010 on it) when copy-pasting console text (like rostopic echo .. output). That makes it much easier to read. Thanks.

Asked by gvdhoorn on 2017-10-06 02:34:43 UTC

thanks gvdhoorn

Asked by JadTawil on 2017-10-07 12:07:32 UTC

Answers