pcl segmentation error when estimate multiple tags

[huiwenzhang]

Hi,

I want to use this package to estimate marker pose. I used a kinect to get depth and camera_info information, which are published on /camera/depth_registered/points and /camera/rgb/camera_info topic. I start the camera driver node, it works fine. and then I start the launch file with ' roslaunch ar_track_alvar pr2_indiv.launch`. The launch file was modified as follows:

<launch>
	<arg name="marker_size" default="5.8" />
	<arg name="max_new_marker_error" default="0.08" />
	<arg name="max_track_error" default="0.2" />

	<arg name="cam_image_topic" default="/camera/depth_registered/points" />
	<arg name="cam_info_topic" default="/camera/rgb/camera_info" />
	<arg name="output_frame" default="/camera_link" />

	<node name="ar_track_alvar" pkg="ar_track_alvar" type="individualMarkers" respawn="false" output="screen">
		<param name="marker_size"           type="double" value="$(arg marker_size)" />
		<param name="max_new_marker_error"  type="double" value="$(arg max_new_marker_error)" />
		<param name="max_track_error"       type="double" value="$(arg max_track_error)" />
		<param name="output_frame"          type="string" value="$(arg output_frame)" />

		<remap from="camera_image"  to="$(arg cam_image_topic)" />
		<remap from="camera_info"   to="$(arg cam_info_topic)" />
	</node>

</launch>

However, once I showed the markers in front of the camera, it throws error as follows:

[pcl::SampleConsensusModel::getSamples] Can not select 0 unique points out of 0!
[pcl::RandomSampleConsensus::computeModel] No samples could be selected!

How can I fix that? @pirobot

[dwhit]

@huiwenzhang Did you ever solve this issue? I am having a similar problem.

[huiwenzhang]

@dwhit Hi, Sorry for late response. I think the problem is still there. I haven't touch the problem for a long time. Now I am using a Xtion camera with a robot. Maybe I will test the function recently.

[Behery]

Did this work with the Xtion camera? I'm currently also using a kinect camera and I'm having the same problem.

[XYudong]

Did this work with the Xtion camera? I'm currently also using a kinect camera and I'm having the same problem.

I am using Kinect having the same issue

[leo-murta95]

@XYudong did u solve it? i have same problem

[divishad12]

I am having the similar issue. Did anyone find the solution?

[tauzn-clock]

This is not exactly a fix but you could use individualMarkersNoKinect with /camera/rgb/image_color. This method may be less accurate as we are using the camera pixel data rather than the lidar data.

I suspect that this is only an issue if the tags used are too small. As the results, the point cloud is too distorted to be processed by pcl. Here is a similar issue I found in another thread. https://github.com/robofit/but_velodyne/issues/32