ROS Resources: Documentation | Support | Discussion Forum | Index | Service Status | ros @ Robotics Stack Exchange
Ask Your Question
0

ar_kinect with pointcloud_throttle

asked 2013-09-09 06:03:22 -0600

Johannes gravatar image

updated 2013-09-10 20:32:32 -0600

Hello, I run the ar_kinect node to detect some ARmarkers. This works fine as long as I do not use pointcoude_throttle nodelet to reduce the amout of calculations.

I started the pointcloud throttle as follows

  <!-- throttling -->
  <node pkg="nodelet" type="nodelet" name="pointcloud_throttle" args="load pointcloud_to_laserscan/CloudThrottle camera_nodelet_manager" respawn="true">
    <param name="max_rate" value="10.0"/>
    <remap from="cloud_in" to="/camera/depth_registered/points"/>
    <remap from="cloud_out" to="/cloud_throttled"/>
  </node>

and the ar_kinect node as follows

<node name="ar_kinect" pkg="ar_kinect" type="ar_kinect" respawn="true" output="screen">
        <param name="marker_pattern_list" type="string" value="$(find bipedRobin_navigation)/data/objects_kinect"/>
        <param name="marker_data_directory" type="string" value="$(find ar_pose)"/>
        <param name="threshold" type="int" value="100"/>
        <remap from="points" to="/cloud_throttled" />
</node>

then I get the following error Failed to find a field named: 'rgb'. Cannot convert message to PCL type.

Using the /cloud_throttled as intput for pointcloud_to_laserscan everything is alright and works.

Next to this issue I asked my self several times what the difference between /camera/depth_register/points, /camera/depth/points and /camera/rgb/points is. Is there somewhere a documentation for the many many outputs from the openni node?

Best Wishes

Johannes Mayr

edit retag flag offensive close merge delete

1 Answer

Sort by ยป oldest newest most voted
1

answered 2013-09-20 19:40:15 -0600

fergs gravatar image

updated 2013-09-20 19:40:58 -0600

Topics with rgb/points or depth_registered/points are typically XYZRGB (that is, colored clouds), those with depth/points are non-colored XYZ clouds.

I have no idea what pointcloud_to_laserscan/CloudThrottle does -- but I'm going to guess it outputs an XYZ cloud and ar_kinect needs XYZRGB. I would suggest looking at using topic_tools throttle node (http://wiki.ros.org/topic_tools) which won't disturb the data.

edit flag offensive delete link more

Question Tools

Stats

Asked: 2013-09-09 06:03:22 -0600

Seen: 350 times

Last updated: Sep 20 '13