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2017-03-24 16:07:26 -0500 asked a question hector_slam with LIDAR not updating map in RVIZ

Hello! I am trying to use ROS Kinetic and a Hokuyo URG LIDAR unit in conjunction with hector_slam in order to produce a map of a room as the robot navigates around it. However, I am running in to some issues.

After running the example launch file, everything seems to be fine. No errors in RVIZ or terminal, and a map is generated based on LIDAR data, like so:

image description

However, as soon as the robot moves, it becomes immediately clear that all is not well after all. Here, we moved the robot physically forward. We can see that the LIDAR input is still updating, as the white dots symbolizing the scanned wall creep closer. However, the map does not update at all, and, even more oddly, seems to be parented to the robot's mobile coordinate frame.

image description

Frankly, I find this behavior very perplexing. I suspect the error may have something to do with this warning, hidden away in the hector launch terminal:

Waiting for tf transform data between frames /map and /base_link to become available

Unfortunately, I have no idea how to make such a transform. FOr reference, however, here is how our transforms are set up by default from hector_slam: image description

The launch file I am calling looks like this:

<?xml version="1.0"?>
<launch>
  <param name="pub_map_odom_transform" value="true"/> 
  <param name="map_frame" value="map"/> 
  <param name="base_frame" value="base_frame"/> 
  <param name="odom_frame" value="base_frame"/>

  <node pkg="urg_node" type="urg_node" name="urg_node"/>
  <node pkg="tf" type="static_transform_publisher" name="map_2_odom" args="0 0 0 0 0 0 /map /odom 100"/>
  <node pkg="tf" type="static_transform_publisher" name="odom_2_base_footprint" args="0 0 0 0 0 0 /odom /base_footprint 100"/>
  <node pkg="tf" type="static_transform_publisher" name="base_footprint_2_base_link" args="0 0 0 0 0 0 /base_footprint /base_link 100"/> 
  <node pkg="tf" type="static_transform_publisher" name="base_link_2_base_stabilized_link" args="0 0 0 0 0 0 /base_link /base_stabilized 100"/> 
  <node pkg="tf" type="static_transform_publisher" name="base_stablized_2_base_frame" args="0 0 0 0 0 0 /base_stabilized /base_frame 100"/> 
  <node pkg="tf" type="static_transform_publisher" name="base_frame_2_laser_link" args="0 0 0 0 0 0 /base_frame /laser 100"/> 
  <node pkg="tf" type="static_transform_publisher" name="base_2_nav_link" args="0 0 0 0 0 0 /base_frame /nav 100"/>
  <node pkg="rviz" type="rviz" name="rviz" args="-d $(find hector_slam_example)/launch/rviz_cfg.rviz"/>
  <include file="$(find hector_slam_example)/launch/default_mapping.launch"/> 
  <include file="$(find hector_geotiff)/launch/geotiff_mapper.launch"/>
</launch>

This file, as you can see, calls two other launch files, the first of which is default_mapping.launch:

<?xml version="1.0"?>

<launch>
  <arg name="tf_map_scanmatch_transform_frame_name" default="scanmatcher_frame"/>
  <arg name="base_frame" default="base_footprint"/>
  <arg name="odom_frame" default="nav"/>
  <arg name="pub_map_odom_transform" default="true"/>
  <arg name="scan_subscriber_queue_size" default="5"/>
  <arg name="scan_topic" default="scan"/>
  <arg name="map_size" default="2048"/>  
  <node pkg="hector_mapping" type="hector_mapping" name="hector_mapping" output="screen">

    <!-- Frame names -->
    <param name="map_frame" value="map" />
    <param name="base_frame" value="$(arg base_frame)" />
    <param name="odom_frame" value="$(arg base_frame)" />

    <!-- Tf use -->
    <param name="use_tf_scan_transformation" value="true"/>
    <param name="use_tf_pose_start_estimate" value="true"/>
    <param name="pub_map_odom_transform" value="$(arg pub_map_odom_transform)"/>

    <!-- Map size / start point -->
    <param ...
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