Gazebo simulator plugin to automatically generate a 2D occupancy map from the simulated world at a given certain height.

This plugin was adapted from the octomap plugin from ETH Zürich.

Check out the plugin in your catkin_ws and build it with catkin_make. To include the plugin, add the following line in between the <world> </world> tags of your Gazebo world file:

<plugin name='gazebo_occupancy_map' filename='libgazebo_2Dmap_plugin.so'>
    <map_resolution>0.1</map_resolution> <!-- in meters, optional, default 0.1 -->
    <map_height>0.3</map_height>         <!-- in meters, optional, default 0.3 -->
    <map_size_x>10</map_size_x>          <!-- in meters, optional, default 10 -->
    <map_size_y>10</map_size_y>          <!-- in meters, optional, default 10 -->
</plugin>

To generate the map, call the /gazebo_2Dmap_plugin/generate_map ros service:

rosservice call /gazebo_2Dmap_plugin/generate_map

The generated map is published on the /map ros topic.

You can use the map_saver node from the map_server package inside ros navigation to save your generated map to a .pgm and .yaml file. To do so, start the node before calling the /gazebo_2Dmap_plugin/generate_map ros service:

rosrun map_server map_saver -f <mapname>

The map is saved once you call the map generation service.

• To identify the connected free space the robot would discover during mapping, the plugin performs a wavefront exploration along the occupancy grid starting from the origin of the gazebo world coordinate system. Please ensure that the corresponding cell is in the continuous free space.
• The plugin will map all objects in the world, including the robot. Remove all unwanted objects before creating the map.