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Creating a fixed frame for a transform frame

I am using the SLAM package on github located here https://github.com/YoshuaNava/icpslam. When I tried to run it against a Velodyne bag file I got no data being read into the pointcloud. I fixed this by altering the launch file to read from the velodyne file. The next issue is that when I try to launch the package in RVIZ I get the error "Fixed frame [velodyne] does not exist" is there a way that I could go in and make velodyne a fixed frame. There is no support on this topic whatsoever. I deleted lines 24-28 in icpslam.launch and replaced them with the code below: 

<param name="laser_cloud_topic" type="string" value="/velodyne_points" />
        <param name="num_clouds_skip" value="20" />
        <param name="voxel_leaf_size" value="0.5" />
        <param name="robot_frame" type="string" value="velodyne" />

Asked by Gordon on 2018-07-10 15:04:59 UTC

Comments

What did you alter? Why? What launch file are you running as I see two (I'm guessing that it's icpslam.launch)?

Asked by jayess on 2018-07-10 16:26:55 UTC

I altered icpslam.launch on line 27 "/spinning_lidar/assembled_cloud" I changed to "/velodyne_points" this is just lines 30-33 uncommented. The reason for doing this is that as it is setup icpslam does not read in from any velodyne lidar bag files.

Asked by Gordon on 2018-07-10 16:35:26 UTC

Can you please update your question with a copy and paste of these changes?

Asked by jayess on 2018-07-10 16:59:17 UTC

param name="laser_cloud_topic" type="string" value="/velodyne_points" />

Asked by Gordon on 2018-07-10 17:00:55 UTC

param name="num_clouds_skip" value="20" />

Asked by Gordon on 2018-07-10 17:03:45 UTC

param name="voxel_leaf_size" value="0.5" />

Asked by Gordon on 2018-07-10 17:04:02 UTC

param name="robot_frame" type="string" value="velodyne" />

Asked by Gordon on 2018-07-10 17:04:18 UTC

Obviously there is a < in front of each of those lines but those are the 4 lines added in the launch files.

Asked by Gordon on 2018-07-10 17:04:46 UTC

Can you please update your question with this code? As you've seen, comments aren't the appropriate place for updates such as this.

Asked by jayess on 2018-07-10 17:15:20 UTC

As for the issue using < and <, you can enter your code into your question (direct copy & paste), highlight it, then use the 101010 button to enable syntax highlighting and code formatting.

Asked by jayess on 2018-07-10 17:16:22 UTC

It's edited now

Asked by Gordon on 2018-07-10 17:23:36 UTC

Do rqt_tf_tree on your bag_file and check the links you have. Probably you need to change the laser_frame to 'velodyne'.

Asked by Choco93 on 2018-07-11 06:10:52 UTC

In which file are you referring to making this change?

Asked by Gordon on 2018-07-11 09:34:05 UTC

in icpslam.launch , under robot_frame, you have laser_frame param.

Asked by Choco93 on 2018-07-12 06:20:18 UTC

This does not change anything. I fixed this and I also changed the frame_id for odom_frame_ and the map_frame_. However, there is also something wrong with the tf_tree. I'm wondering if there is a bag file to test this program.

Asked by Gordon on 2018-07-17 10:17:07 UTC

Answers