Hello!

I am currently testing the impact of a virtual sensor on the global and local costmap and the global and local path. Unfortunately the robot I am using got a defect - so I would like to run the move_base node without running the turtlebot.

Therefore I run 2 mapserver nodes, the virtual_sensor node and a movebase node:

• The first map_server publishes the actual map
• The second map_server publishes a map which defines the extend of a point cloud published by the virtual sensor.
• The virtual_sensor simulates a pointcloudsensor and therefore publishes a point cloud which is generated based on the second map_servers map.
• For the movebase node I defined the point cloud published by the virtual sensor as a pointcloudsensor in the "costmapcommon_params.yaml" file.

Unfortunately I keep getting the following warning when launching the corresponding launch file (see below):[ WARN] [1335514446.971956660]: Waiting on transform from /base_link to /map to become available before running costmap, tf error:

Obviously the movebase node needs more data to work properly: As far as I understand there is no /baselink frame, because the turtlebot is not activated. But how can I publish this data without robot? And which other data will be necessary to run the move_base and test the costmap/path output? Or is there an easy way to simulate the robot, so that I do not have to publish additional data separately.

My corresponding launch file contains the following:

    <launch>

      <!-- Run the move_base map server -->
      <arg name="map_file" default="/home/.../map.yaml"/>
      <node name="move_base_map_server" pkg="map_server" type="map_server" args="$(arg map_file)"/>

      <!-- Run the virtual map server -->
      <arg name="virtual_sensor_map_topic" default="virtual_sensor_map"/>
      <arg name="virtual_sensor_map_file" default="/home/ .../virtual_sensor_map.yaml"/>
      <node name="virtual_sensor_map_server" pkg="map_server" type="map_server" args="$(arg virtual_sensor_map_file)">
        <remap from="map" to="$(arg virtual_sensor_map_topic)"/>
      </node>

      <!--- Run Move Base -->
      <node pkg="move_base" type="move_base" respawn="false" name="move_base" output="screen">
        <rosparam file="$(find roomba_navigation)/params/costmap_common_params.yaml" command="load" ns="global_costmap" />
        <rosparam file="$(find roomba_navigation)/params/costmap_common_params.yaml" command="load" ns="local_costmap" />
        <rosparam file="$(find roomba_navigation)/params/local_costmap_params.yaml" command="load" />
        <rosparam file="$(find roomba_navigation)/params/global_costmap_params.yaml" command="load" />
        <rosparam file="$(find roomba_navigation)/params/base_local_planner_params.yaml" command="load" />
      </node>

      <!-- Run the virtual sensor -->
      <node name="virtual_sensor" pkg="virtual_sensor" type="virtual_sensor_publisher"/>
    </launch>

Thank you for your help.

Regards scr