laserscan_visualizer - configuring range not working

[didrif14]

Hello.

I am trying to use the laserscan_visualizer to convert a pointcloud to a laserscan. The pointcloud comes from a gazebo kinect plugin. I can visualize the laserscan in rviz, however, the laserscan is only shown approximately 2 meters infront of the robot, even though i have set the range to 25 meters.

I have removed the TF statements, because my TF is published though robot-state-publisher. This is my launch file:

`

<param name ="/use_sim_time" value="true"/>

  <!-- DEFINE HERE THE STATIC TRANFORMS, FROM BASE_FRAME (COMMON REFERENCE FRAME) TO THE VIRTUAL LASER FRAMES-->
    <!-- WARNING: the virtual laser frame(s) *must* match the virtual laser name(s) listed in param: output_laser_scan -->

    <node pkg="ira_laser_tools" name="laserscan_virtualizer" type="laserscan_virtualizer" output="screen">
            <param name="cloud_topic" value="/frnt_cam_lnk/depth/points"/>       <!-- INPUT POINT CLOUD -->
            <param name="base_frame" value="/laser_lnk"/>     <!-- REFERENCE FRAME WHICH LASER(s) ARE RELATED-->
            <param name="output_laser_topic" value ="/frnt_scan" />  <!-- VIRTUAL LASER OUTPUT TOPIC, LEAVE VALUE EMPTY TO PUBLISH ON THE VIRTUAL LASER NAMES (param: output_laser_scan) -->
			<param name="angle_min" value ="-3.14" />
			<param name="angle_max" value ="3.14" />
			<param name="angle_increment" value ="0.0058" />
			<param name="range_min" value ="0.45" />
			<param name="range_max" value ="25" />
            <param name="virtual_laser_scan" value ="/frnt_cam_p2l" /> <!-- LIST OF THE VIRTUAL LASER SCANS. YOU MUST PROVIDE THE STATIC TRANSFORMS TO TF, SEE ABOVE -->
    </node>

`

[trigal]

do you have a bag with some data?

[didrif14]

do you have a bag with some data?

Thanks for your quick response! I recorded the laserscan and uploaded it here: https://drive.google.com/file/d/1zpugHnILWYGGUH686pbKak7r3IzMwbq7/view?usp=sharing

Altough it has some errors stating: `For frame [/frnt_cam_p2l]: Fixed Frame [map] does not exist' Here is my tf-tree: https://drive.google.com/file/d/1yToZ48NtmCslbveEh5wmPaDoPBwmPaOz/view?usp=sharing

I uploaded a short video which shows the pointcloud, and how the laserscan is visualized. https://youtu.be/gBR92UYLipE

[trigal]

It has been a very long time since the last time I used this tool, we mainly use the laser merger one. However, let's see, the laser data in your bag (that is that output from the virtualizer I suppose) is in the frame frnt_cam_p2l. The original point cloud points in which frame are they in? I suppose laser_link, am I correct? Could you upload a bag with TF as the point cloud as well?

From the bagfile: header: seq: 1457 stamp: secs: 161 nsecs: 825000000 frame_id: /frnt_cam_p2l angle_min: -3.1400001049 angle_max: 3.1400001049 angle_increment: 0.00579999992624 time_increment: 0.0 scan_time: 0.0333333313465 range_min: 0.449999988079 range_max: 25.0

[didrif14]

My plan is to convert the pointclouds to laserscan, then merge four laserscans with the multi-merger.

I realize that I might have configured the launch file incorrect. The pointcloud comes from the frnt_cam_opt frame. The frame where I want the new laser scan (frnt_scan) is frnt_cam_p2l. Ultimately I want to merge my four laserscan to the laser_lnk frame.

I have uploaded two .bag files, one contains tf and laserscan, the other contains tf and pointcloud.

Tf and laser: https://drive.google.com/file/d/1M0P72A9AXiJY7WzBDJGQH_OFTCz6JVJh/view?usp=sharing

Tf and pointcloud: https://drive.google.com/file/d/1ajPpfPThBCS3gpvTRVtYUdZl62lSfC8G/view?usp=sharing

The pointcloud .bag file is very large, maybe I have to reduce the resolution from the kinect plugin?

[trigal]

from your bag file (the tf points) it seems that you're publishing the transformation between these two frames always at the same time, to be clear, not with row::time::now() I'm not sure if this might be the issue, but could you please check? TF has a standard time-window with 10 secs..

so your configuration is 4 kinects on the robot and you want to simulate 4 lasers and then merge them?

rosrun tf tf_echo /frnt_cam_opt /frnt_cam_p2l
At time 0.000
- Translation: [0.000, 0.000, 0.000]
- Rotation: in Quaternion [0.707, 0.000, 0.000, 0.707]
            in RPY (radian) [1.571, -0.000, 0.000]
            in RPY (degree) [90.000, -0.000, 0.000]
At time 0.000
- Translation: [0.000, 0.000, 0.000]
- Rotation: in Quaternion [0.707, 0.000, 0.000, 0.707]
            in RPY (radian) [1.571, -0.000, 0.000]
            in RPY (degree) [90.000, -0.000, 0.000]

header: 
  seq: 1672
  stamp: 
    secs: 84
    nsecs: 239000000
  frame_id: frnt_cam_opt
height: 512
width: 512
fields: 

[didrif14]

from your bag file (the tf points) it seems that you're publishing the transformation between these two frames always at the same time, to be clear, not with row::time::now()

I am not quite sure how to do this, as the tf is being published by the /state_publisher

so your configuration is 4 kinects on the robot and you want to simulate 4 lasers and then merge them?

Correct. I have managed to use a depth image to laserscan package, and used your merger to combine them.

[trigal]

I see, but if you open your tf-tree you will notice that all the Kinects have very old transforms (105secs ... I suppose just the first one, at the time you "power on" your system) and no more. Instead, frw_link, rlw_link, and rrw_link have updated transforms. This might be an issue and, from what you have told me, maybe the problems arise from the depth-to-laserscan package configuration. Your state publisher is not updating all the transforms, I don't know why.

[didrif14]

I have noticed the same thing, however, I assumed it was correct because these are fixed frames with respect to the base_lnk. Whereas the rrw rlw frw flw links are wheels and are constantly turning. But if that is not the case, I should probably find the reason for this.

[trigal]

But just to understand if the package is working properly, can you directly use the data from the kinect without all the system and transformations? I have vague memories, but this should have been exactly what we did when we wrote this package, but is was 6 ore more years ago... don’t remember any details