how to run with a real robot(GO2_W)

[2022guo]

Now i have already run the dddmr_navigation in gazebo,but i don't know how to run it with a real rorbt,could you teach me step by step? I am just getting in touch with the ROS2.thanks a lot!

[tsengapola]

Let's start following

1. Create docker images
2. Create docker container and compile dddmr_navigation stack
3. Make sure your lidar is publishing topic
4. Try to launch lego loam to map

[G7-3208]

Let's start following

1. Create docker images
2. Create docker container and compile dddmr_navigation stack
3. Make sure your lidar is publishing topic
4. Try to launch lego loam to map

hi @tsengapola I am currently also trying to use lego_loam for mapping. I have a mid360 LiDAR. I subscribed directly to the LiDAR data, but lego_loam failed to start. What should I do?

[tsengapola]

Let debug step by step, can you show me:
Do not run anything, only run mid360 lidar node.

1. Show me ros2 topic list
2. Show me TF tree

[G7-3208]

让我一步步调试，你能给我演示一下吗：不要运行任何东西，只运行mid360 lidar节点。

1. 给我看看ros2主题列表
2. 给我看看TF树

Thank you for your reply. Here is the rqt image after I launched it with "ros2 launch livox_ros_driver2 rviz_MID360_launch.py" ...
ll@ubuntu:~$ ros2 topic list
/clicked_point
/goal_pose
/ground_cloud
/initialpose
/livox/imu
/livox/lidar
/move_base_simple/goal
/parameter_events
/rosout
/tf
/tf_static

[tsengapola]

OK, good, We need to create a tf tree, so I need to know your lidar frame.
Can you do ros2 topic echo /livox_lidar_publisher --no-arr when your lidar is launched

[G7-3208]

Yes，Here they are ll@ubuntu:~$ ros2 topic echo /livox/lidar --no-arr
header:
stamp:
sec: 1772531801
nanosec: 892993386
frame_id: livox_frame
height: 1
width: 19968
fields: '<sequence type: sensor_msgs/msg/PointField, length: 7>'
is_bigendian: false
point_step: 26
row_step: 519168
data: '<sequence type: uint8, length: 519168>'
is_dense: true

header:
stamp:
sec: 1772531801
nanosec: 992863673
frame_id: livox_frame
height: 1
width: 20064
fields: '<sequence type: sensor_msgs/msg/PointField, length: 7>'
is_bigendian: false
point_step: 26
row_step: 521664
data: '<sequence type: uint8, length: 521664>'
is_dense: true

header:
stamp:
sec: 1772531802
nanosec: 92941965
frame_id: livox_frame
height: 1
width: 19968
fields: '<sequence type: sensor_msgs/msg/PointField, length: 7>'
is_bigendian: false
point_step: 26
row_step: 519168
data: '<sequence type: uint8, length: 519168>'
is_dense: true

[tsengapola]

So your launch file will look like:

<launch>

  <!--name argument is not required, because it will overwrite all node name in the exec-->
  <node pkg="lego_loam_bor" exec="lego_loam" output="screen" respawn="false">
    <param from="$(find-pkg-share lego_loam_bor)/config/loam_mid360_config.yaml" />
    <remap from="/lslidar_point_cloud" to="/livox_lidar_publisher"/>
    <remap from="/odom" to="/odom"/>
  </node>

  <node pkg="rviz2" exec="rviz2" output="screen" respawn="false" args="-d $(find-pkg-share lego_loam_bor)/rviz/lego_loam.rviz">
  </node>

  <!--- TF -->
  <node pkg="tf2_ros" exec="static_transform_publisher" name="sensor2baselink"  args="0.0 0 0.0 0.0 0.0 0 base_link livox_frame" />
  
</launch>

And your loam_mid360_config.yaml:

lego_loam_ip:
  ros__parameters:
    use_sim_time: true
    # leishen16
    laser:
        odom_type: "laser_odometry"         #wheel_odometry/laser_odometry 
        baselink_frame: "base_link"
        num_vertical_scans: 32
        num_horizontal_scans: 1000
        vertical_angle_bottom: -7.0          # degrees
        vertical_angle_top: 52.0            # degrees
        scan_period: 0.1                   # seconds

    imageProjection:
        segment_valid_point_num: 5
        segment_valid_line_num: 2
        segment_theta: 60.0                      # decrese this value may improve accuracy
        minimum_detection_range: 0.5
        maximum_detection_range: 100.0            # point cloud within this range will be used to project image
        distance_for_patch_between_rings: 1.0    # patch ground between rings within this range, i.e. ring0 and ring1 is smaller than 1 meter, patch them
        stitcher_num: 3                          # for non-repetitive scan lidar use 2~4 (i.e. mid360)
        trt_model_path: ""                       # provide trt engine for yolo
        projected_image_stack_size: 1            # Stack this number of image for yolo11n to inference as time elapsed yolo (only work when TRT is loaded)
        
        ground_fov_bottom: -0.2617994 # -15deg
        ground_fov_top: -0.087266 # -5deg
        ground_positive_start: 0.0
        ground_positive_stop: 3.1415926
        ground_negative_start: 0.0
        ground_negative_stop: -3.1415926

lego_loam_fa:
  ros__parameters:
    use_sim_time: true
    featureAssociation:                              
        edge_threshold: 0.1
        surf_threshold: 0.1
        nearest_feature_search_distance: 3.0

    mapping:
        to_map_optimization: true

lego_loam_mo:
  ros__parameters:
    use_sim_time: true
    mapping:

        distance_between_key_frame: 1.0
        angle_between_key_frame: 1.0

        enable_loop_closure: true

        surrounding_keyframe_search_num: 20
        history_keyframe_search_radius: 12.0
        history_keyframe_search_num: 5
        history_keyframe_fitness_score: 0.5
        
        ground_voxel_size: 0.3
        ground_edge_threshold_num: 50

Is your mid360 tilted?

[G7-3208]

Thank you again for your guidance. My radar is currently not tilted, and now I have a map like this. Is it ok?I also have a robot (GO2). May I ask what the next step is if I want to navigate using the GO2

[tsengapola]

Check your ground point cloud, are you in a narrow space? There are only few points in your ground.
Next step is to compile dddmr_navigation stack and run it. Do you succeed create a docker container using our docker image?

[G7-3208]

Yes, I placed the radar on the desk, and there are quite a few obstructions. I have successfully created a Docker container using your Docker image, but I am not sure what to do next.

[tsengapola]

Execute into the container and colcon build:

docker exec -it your_container bash
cd dddmr_navigation
colcon build --symlink-install --cmake-args -DCMAKE_BUILD_TYPE=Release

Also, does this container run on your GO2_W computer, or can it communicate with your GO2_W?
Also try to map the area using your Go2, and save the map, so that you can later localize your robot and make it autonomous.

[G7-3208]

I have built all the packages, and this container can communicate with my GO2. Is the mapping you mentioned done using lego_loam? If so, can lego_loam automatically save the map?

[tsengapola]

if you are doing live mapping (not using bag to geberate the map), use this command in terminal:

ros2 service call /save_mapped_point_cloud std_srvs/srv/Empty {}

The map will be saved in /tmp, basically it is a folder named by date, copy the folder into dddmr_bags

[G7-3208]

Thank you for your patient reply, and sorry for my many and silly questions. I have now obtained my map file. Could you please tell me what to do next? Where is the dddmr_bags folder? I couldn't find it. Also, after I put it in the dddmr_bags folder, what should I do?

[tsengapola]

In your docker container, you should see dddmr_bags which is being mounted from host to your container.
Please make sure your container is initialized using our script. The location in your container should be

/root/dddmr_bags

Once this is done, next step is to launch localization and navigation mode.

ros2 launch p2p_move_base p2p_move_base_localization.launch

Make sure you change the map directory to your map folder:

dddmr_navigation/src/dddmr_p2p_move_base/config/p2p_move_base_localization.yaml

Line 57 in 9e38ea0

pose_graph_dir: "/root/dddmr_bags/benanli_detention_basin_pg"