URG-04LX / RPLIDAR - lookupTransform base_link to laser

asked 2017-08-15 13:54:33 -0600

gerard gravatar image

updated 2017-08-15 14:17:29 -0600

First of all thank you for your future answers.

I have been searching the forum for an explanation for the following error, but I can not find it.

I use the same code in two different robots with the same topics.

In the first one, which uses a hokuyo URG-04LX and publishes the scan topic, I run hector_mapping and hector_geotiff launches and with that I can make my map correctly.

On the other run, which uses a RPLIDAR and also publishes the scan topic, I do the same and I get the following error:

[ INFO] [1502821857.396404571]: lookupTransform base_link to laser timed out. Could not transform laser scan into base_frame.

If I run a "rosrun tf view_frames" i get odom -> base_link -> laser, so the transform between the base_link and the laser seems to be correct. So why I get the error?

Here is my hector_mapping launch file:


<arg name="tf_map_scanmatch_transform_frame_name" default="scanmatcher_frame"/>
<arg name="base_frame" default="base_link"/>
<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="base_link" />
<param name="odom_frame" value="base_link" />

<!-- 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"/>

<!-- Map size / start point -->
<param name="map_resolution" value="0.050"/>
<param name="map_size" value="$(arg map_size)"/>
<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" />
<param name="laser_z_min_value" value = "-1.0" />
<param name="laser_z_max_value" value = "1.0" />

<node pkg="tf" type="static_transform_publisher" name="base_to_laser_broadcaster"      args="0 0 0 0 0 0 /base_link /laser 100" />


Thank you!

edit retag flag offensive close merge delete


I'm a little confused. Are you running the code on the same master on two different robots at the same time using the same topic names?

jayess gravatar image jayess  ( 2017-08-15 16:01:26 -0600 )edit

No, in different masters.

My new question is: why if I run the rplidar node before the hector_mapping launcher I get the error:

But if I run hector_mapping and hector_geotiff launchers before run the rplidar node everything is fine and I get the map?

gerard gravatar image gerard  ( 2017-08-20 19:00:19 -0600 )edit

If you have a new question then you should create a new one.

jayess gravatar image jayess  ( 2017-08-20 20:56:51 -0600 )edit