Poor map using demo_depth_camera_2d.launch

[tiaopao]

Thanks a lot for the great work!
When I am running the demos, I have some questions, would you please help us to improve it?

1. Environment:

1. Ubuntu 16.04
2. ROS kinetic
3. Building and Installation refered to https://google-cartographer-ros-for-turtlebots.readthedocs.io/en/latest/
4. cartographer_turtlebot: Latest version
5. cartographer: version 1.0.0
6. cartographer_ros: version 1.0.0
7. ceres-solver: version 1.13.0

2. Launch Lidar Demo with bag cartographer_turtlebot_demo.bag

1. Command Line:
   roslaunch cartographer_turtlebot demo_lidar_2d.launch bag_filename:=${HOME}/Downloads/cartographer_turtlebot_demo.bag
2. Map result as follows
   

3. Launch 2D Depth Camera demo with bag cartographer_turtlebot_demo.bag

1. Command Line:
   roslaunch cartographer_turtlebot demo_depth_camera_2d.launch bag_filename:=${HOME}/Downloads/cartographer_turtlebot_demo.bag
2. Map result as follows
   

4. Questions?

1. The above two demos use the same bag (cartographer_turtlebot_demo.bag), so I think they should output the similar map, am I right? If no, would you please correct me.
2. To make the 2D Depth Camera demo output the good map that is the same as Lidar Demo, how to tuning the parameters?

Let me know if you need any other files or information in order to reproduce the issue. Thanks!

[gaschler]

This seems like a regression in demo_depth_camera_2d.launch.
Of course, the input is very noisy, but there was a time when all launch files created a valid map.

[tiaopao]

@gaschler Thanks a lot for your help.

1. I had read all the issues of this project, and improve the configuration file "turtlebot_depth_camera_2d.lua", please find here, the map results as follows. This map is only better, but it is unusable still. I guess the key issue is that the horizontal FOV of the 2D depth camera is small so that CeresScanMatcher generated some unreliable match. Could you please give me some suggestions about how to tuning parameters (e.g.: what are the key parameters for this issue), or improving the code "local_trajectory_builder_2d.cc" (e.g.: which key results should be checked)?
   

2. You said " Of course, the input is very noisy, but there was a time when all launch files created a valid map."
   Would you please tell me what time did all launch files create a valid map, so that I test it and find the difference?

[gaschler]

Would you please tell me what time did all launch files create a valid map, so that I test it and find the difference?

@SirVer, can you perhaps point to a version when demo_depth_camera_2d.launch created a map?

I had read all the issues of this project, and improve the configuration file "turtlebot_depth_camera_2d.lua", please find here, the map results as follows. https://github.com/tiaopao/doc/blob/master/cartographer/turtlebot_depth_camera_2d.lua#L54

This would fix local SLAM to constant velocity, so this unfortunately doesn't solve it.

I'd rather try out fine changes to hit/miss_probability and/or real_time_correlative_scan_matcher with a small search window, and setting the ceres translation_weight rather low.

Please find the tuning guide here: https://google-cartographer-ros.readthedocs.io/en/latest/tuning.html

[tiaopao]

@gaschler Thanks for your great suggestions, I will try it.

[tiaopao]

Command Line:

roslaunch cartographer_turtlebot demo_lidar_2d.launch bag_filename:=${HOME}/Downloads/cartographer_turtlebot_demo.bag

Code version 0.1.0

• cartographer: version 0.1.0
• cartographer_ros: version 0.1.0
• cartographer_turtlebot: version 0.1.0
• ceres-solver: version 1.13.0
• map results:
  

Code version 0.2.0

• cartographer: version 0.2.0
• cartographer_ros: version 0.2.0
• cartographer_turtlebot: version 0.2.0
• ceres-solver: version 1.13.0
• map results:
  

Code version 0.3.0

• cartographer: version 0.2.0
• cartographer_ros: version 0.2.0
• cartographer_turtlebot: version 0.2.0
• ceres-solver: version 1.13.0
• When running, there is an exception.

Question

@SirVer which version is correct for the map?