Improve gmapping results

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Not sure if you've got the same issue I had - but my fix here was to set the minimumScore parameter to a very large value.

I mapped with hector slam. Using odometry with it, I was able to create this map:

This is pretty close to the original. I don't have the ground truth image, so I cannot make any comparison locally, but, trusting my eyes, it seems to be a pretty good one. Playing with parameters in a launch file, you can probably improve it. Here is the launch file I used to create the above:

<?xml version="1.0"?>

<launch>

  <node pkg="hector_mapping" type="hector_mapping" name="hector_mapping" output="screen">

    <!-- Topic names -->
    <param name="scan_topic" value="base_scan" />    

    <!-- Frame names -->
    <param name="base_frame" value="base_laser_link" />
    <param name="odom_frame" value="odom"/>
    <param name="output_timing" value="false"/>

    <!-- Tf use -->
    <param name="use_tf_scan_transformation" value="true"/>
    <param name="use_tf_pose_start_estimate" value="false"/>
    <param name="pub_map_odom_transform" value="true"/>
    <param name="advertise_map_service" value="true"/>

    <!-- Map size / start point -->
    <param name="map_resolution" value="0.050"/>
    <param name="map_size" value="2048"/>
    <param name="map_start_x" value="0.5"/>
    <param name="map_start_y" value="0.5" />
    <param name="map_multi_res_levels" value="2" />

    <!-- Map update parameters -->
    <param name="update_factor_free" value="0.4"/>
    <param name="update_factor_occupied" value="0.9" />    
    <param name="map_update_distance_thresh" value="0.4"/>
    <param name="map_update_angle_thresh" value="0.06" />

    <!-- Debug parameters -->
    <!--
      <param name="pub_drawings" value="true"/>
      <param name="pub_debug_output" value="true"/>
    -->
  </node>

  <node pkg="hector_trajectory_server" type="hector_trajectory_server" name="hector_trajectory_server" output="screen">
    <param name="target_frame_name" type="string" value="/map" />
    <param name="source_frame_name" type="string" value="/base_link" />
    <param name="trajectory_update_rate" type="double" value="4" />
    <param name="trajectory_publish_rate" type="double" value="0.25" />
  </node>

  <node pkg="hector_geotiff" type="geotiff_node" name="hector_geotiff_node" output="screen" launch-prefix="nice -n 15">
    <remap from="map" to="/dynamic_map" />
    <param name="map_file_path" type="string" value="$(find hector_geotiff)/maps" />
    <param name="map_file_base_name" type="string" value="hector_slam_map" />
    <param name="geotiff_save_period" type="double" value="10" />
    <param name="draw_background_checkerboard" type="bool" value="true" />
    <param name="draw_free_space_grid" type="bool" value="true" />
  </node>

</launch>

To run the bag in simtime, use this command:

rosbag play <bagfile>.bag --clock

If you have a good source of incoming data, you should fit the motion model to it. That are the srr,srt,... parameters. You should lower them to reflect the actual error you have.

Also the laser should fit the scale of the environment, so it sees as much as possible. The LMS200 max range is 80m, AFAIK only the prototypes had 8m.

PS: If you just want to have a perfect map, you can just use your blue ground truth image and convert it to pgm + write the yaml file.