Mapping using Rtabmap

[Engy]

while executing mapping.launch i received the following warning and i couldn't find 2d map
Is there any solution to generate 2d occupancy grid map
I found that all topics are mapped well

[matlabbe]

Is the scan valid? If you do:

$ rostopic echo /scan

Are there values and not all "inf"?

[Engy]

that was the output
some values are zero and the others are inf

[matlabbe]

It looks like the lidar cannot see any structures. You may have to debug why the lidar is returning only inf values.

[Engy]

Excuse me, what are the possible reasons behind this issue ?!

[matlabbe]

Is it in simulation? or with a real lidar?

[Engy]

simulation

[matlabbe]

I know that when running Gazebo in some virtual machines (and maybe computers without dedicated GPU), the laser plugin cannot hit any obstacles. Seem to be a GPU problem: https://bitbucket.org/osrf/subt/issues/11/x2-laser-scanner-data-not-valid

On which kind of computer is Gazebo running?

[Engy]

I run it on udacity workspace while enabling GPU
it is on of the robotics nanodegree program tasks

[matlabbe]

Is the gazebo world empty? Otherwise you may ask them why the lidar is seeing only inf values in their environment. Another post to look up: http://answers.gazebosim.org/question/13497/laserscanner-look-through-objects/

[Engy]

thank you for your help
but I have a final question how to update rtabmap and rtabmaprviz
I want to get 2D occupancy grid map from rtabmaprviz

[matlabbe]

Subscribe to /rtabmap/grid_map topic (an output of rtabmap node). However, as long you have the lidar problem, you will get an empty map.

[Engy]

I get the 3d map on rtabmaprviz but I could not get the 2d

[Engy]

<?xml version="1.0" encoding="UTF-8"?>

<launch>
 
  <arg name="database_path"     default="rtabmap.db"/>
  <arg name="rgb_topic"         default="/camera/rgb/image_raw"/>
  <arg name="depth_topic"       default="/camera/depth/image_raw"/>
  <arg name="camera_info_topic" default="/camera/rgb/camera_info"/> 
 
 
  <group ns="rtabmap">
    <node name="rtabmap" pkg="rtabmap_ros" type="rtabmap" output="screen" args="--delete_db_on_start">
       
       
       
       
       
       
       
       
       

       
        <remap from="scan"            to="/scan"/>
        <remap from="rgb/image"       to="$(arg rgb_topic)"/>
        <remap from="depth/image"     to="$(arg depth_topic)"/>
        <remap from="rgb/camera_info" to="$(arg camera_info_topic)"/>

       
        <remap from="grid_map" to="/map"/>

       
         

       
             

       
       
         
               
       
       
         
       
       
       
       
       
       
         
       
       
         
       
       
       
       
    </node>

   
   
    <node pkg="rtabmap_ros" type="rtabmapviz" name="rtabmapviz" args="-d $(find rtabmap_ros)/launch/config/rgbd_gui.ini" output="screen">
     
     
     
     
      <remap from="rgb/image"       to="$(arg rgb_topic)"/>
      <remap from="depth/image"     to="$(arg depth_topic)"/>
      <remap from="rgb/camera_info" to="$(arg camera_info_topic)"/>
      <remap from="scan"            to="/scan"/>
      <remap from="odom"            to="/odom"/>
    </node>
   
  </group>
</launch>

[Engy]

the previous was my mapping.launch file
how could I subscribe ??

[matlabbe]

In RVIZ, you can add Occupancy grid display and subscribe to /map topic in your case.

In rtabmapviz, you can do "Window->Show view-> Graph view" to show a 2d view with the grid. To show in 3D Map panel, you should enable "Preferences->3D Rendering->Grid Map Assembling->Show in 3D Map view"

You can add

<param name="Grid/FromDepth" value="true"/>

under rtabmap node to create the 2D map from the depth image projection instead of laser scan (until you find a solution of inf values in the scans)