MarkerArray msg has an empty element

[ricber]

Hi, I'm having a problem on the following configuration: Ubuntu 16.04 ROS Kinetic

The problem is that the MarkerArray message has one of the elements of the array with an empty frame_id. See the following terminal output, there is an empty frame_id message just after the frame_id: "map" ns: "edges" one:

markers: 
  - 
    header: 
      seq: 0
      stamp: 
        secs: 1574692887
        nsecs: 223545959
      frame_id: "map"
    ns: "nodes"
    id: 0
    type: 7
    action: 0
    pose: 
      position: 
        x: 0.0
        y: 0.0
        z: 0.0
      orientation: 
        x: 0.0
        y: 0.0
        z: 0.0
        w: 1.0
    scale: 
      x: 0.5
      y: 0.5
      z: 0.5
    color: 
      r: 0.0
      g: 0.0
      b: 0.0
      a: 0.0
    lifetime: 
      secs: 0
      nsecs:         0
    frame_locked: False
    points: 
      - 
        x: 0.0
        y: 0.0
        z: 0.0
    colors: 
      - 
        r: 1.0
        g: 0.0
        b: 0.0
        a: 1.0
    text: ''
    mesh_resource: ''
    mesh_use_embedded_materials: False
  - 
    header: 
      seq: 0
      stamp: 
        secs: 1574692887
        nsecs: 223545959
      frame_id: "map"
    ns: "edges"
    id: 1
    type: 5
    action: 0
    pose: 
      position: 
        x: 0.0
        y: 0.0
        z: 0.0
      orientation: 
        x: 0.0
        y: 0.0
        z: 0.0
        w: 1.0
    scale: 
      x: 0.05
      y: 0.0
      z: 0.0
    color: 
      r: 0.0
      g: 0.0
      b: 0.0
      a: 0.0
    lifetime: 
      secs: 0
      nsecs:         0
    frame_locked: False
    points: []
    colors: []
    text: ''
    mesh_resource: ''
    mesh_use_embedded_materials: False
  - 
    header: 
      seq: 0
      stamp: 
        secs: 0
        nsecs:         0
      frame_id: ''
    ns: ''
    id: 0
    type: 0
    action: 0
    pose: 
      position: 
        x: 0.0
        y: 0.0
        z: 0.0
      orientation: 
        x: 0.0
        y: 0.0
        z: 0.0
        w: 0.0
    scale: 
      x: 0.0
      y: 0.0
      z: 0.0
    color: 
      r: 0.0
      g: 0.0
      b: 0.0
      a: 0.0
    lifetime: 
      secs: 0
      nsecs:         0
    frame_locked: False
    points: []
    colors: []
    text: ''
    mesh_resource: ''
    mesh_use_embedded_materials: False
  - 
    header: 
      seq: 0
      stamp: 
        secs: 1574692887
        nsecs: 223545959
      frame_id: "map"
    ns: "loop_close_radius"
    id: 0
    type: 2
    action: 0
    pose: 
      position: 
        x: 0.0
        y: 0.0
        z: 0.0
      orientation: 
        x: 0.0
        y: 0.0
        z: 0.0
        w: 1.0
    scale: 
      x: 2.0
      y: 2.0
      z: 2.0
    color: 
      r: 1.0
      g: 0.0
      b: 0.0
      a: 0.300000011921
    lifetime: 
      secs: 0
      nsecs:         0
    frame_locked: False
    points: []
    colors: []
    text: ''
    mesh_resource: ''
    mesh_use_embedded_materials: False
  - 
    header: 
      seq: 0
      stamp: 
        secs: 1574692887
        nsecs: 223545959
      frame_id: "map"
    ns: "imu"
    id: 4
    type: 7
    action: 0
    pose: 
      position: 
        x: 0.0
        y: 0.0
        z: 0.0
      orientation: 
        x: 0.0
        y: 0.0
        z: 0.0
        w: 1.0
    scale: 
      x: 0.75
      y: 0.75
      z: 0.75
    color: 
      r: 0.0
      g: 0.0
      b: 0.0
      a: 0.0
    lifetime: 
      secs: 0
      nsecs:         0
    frame_locked: False
    points: []
    colors: []
    text: ''
    mesh_resource: ''
    mesh_use_embedded_materials: False
---

I use the hdl_graph_slam.launch file with the nodelet_manager line commented out as I use the velodyne_driver. So, I first start hdl_graph_slam, then Rviz, then the velodyne_driver. For some tens of seconds, I correctly see the map building on Rviz but after a while, I get this error message from Rviz: [ WARN] [1574694951.774019641]: MessageFilter [target=map ]: Discarding message from [unknown] due to empty frame_id. This message will only print once. [ WARN] [1574694951.774175074]: Invalid argument passed to canTransform argument source_frame in tf2 frame_ids cannot be empty However, no errors are printed from hdl_graph_slam nor from the velodyne_nodelet_manager. Moreover, I have the same problem with the 501 bag file. I can correctly see the map building and the laser odometry trajectory but a MarkerArray msg has empty frame_id.

Can you help me? Thank you :)

EDIT

I've gone through the code of the hdl_graph_slam_nodelet.cpp file and the create_marker_array function is not filling markers.markers[2]. Here is the reason of the error. Can you fix it?

[koide3]

Hi @ricber , Yes, it's a known issue caused by markers.markers[2] which is always empty. Since it was not very serious (just shows warnings) and I was a bit busy last year, I forgot to fix it. I'll update the code soon. Thank you for reporting it :)

[jkoubs]

Hello were you able to resolve this error ? Thank you

[Franzisdrak]

I am having the same issue. But i don't use the graph slam. Might be due to something in the source code of the MarkerArray?