No map topic and visualization

[ShameerMasroor]

Hello!

I am trying to integrate your work with a project that I am working on.

My project involves using a drone affixed with a 3D Lidar to map a forest and localize itself.

My drone publishes the following topics, the relevant ones are /scan and /imu/out, and the namespace is simple_drone.

/scan is published as a topic with a message type of PointCloud2, and the IMU topic is of type Imu.

I tried to remap the parameters in the lidar_slam.launch.py file to the ones for my drone, as shown in the following code:

import os

import launch
import launch_ros.actions

from ament_index_python.packages import get_package_share_directory

def generate_launch_description():

main_param_dir = launch.substitutions.LaunchConfiguration(
    'main_param_dir',
    default=os.path.join(
        get_package_share_directory('lidarslam'),
        'param',
        'lidarslam.yaml'))

rviz_param_dir = launch.substitutions.LaunchConfiguration(
    'rviz_param_dir',
    default=os.path.join(
        get_package_share_directory('lidarslam'),
        'rviz',
        'mapping.rviz'))

mapping = launch_ros.actions.Node(
    package='scanmatcher',
    executable='scanmatcher_node',
    parameters=[main_param_dir],
    remappings=[('/input_cloud','/simple_drone/scan')],
    output='screen'
    )

tf = launch_ros.actions.Node(
    package='tf2_ros',
    executable='static_transform_publisher',
    arguments=['0','0','0','0','0','0','1','simple_drone/base_link','simple_drone/laser_frame']
    )


graphbasedslam = launch_ros.actions.Node(
    package='graph_based_slam',
    executable='graph_based_slam_node',
    parameters=[main_param_dir],
    output='screen'
    )

rviz = launch_ros.actions.Node(
    package='rviz2',
    executable='rviz2',
    arguments=['-d', rviz_param_dir]
    )


return launch.LaunchDescription([
    launch.actions.DeclareLaunchArgument(
        'main_param_dir',
        default_value=main_param_dir,
        description='Full path to main parameter file to load'),
    mapping,
    tf,
    graphbasedslam,
    rviz,
        ])`

What I feel that the issue lies in is with the transform frames. Do I need to make a transformation between the map and the base_link of the drone? Apologies as I am a beginner with ROS at the moment.

Terminal output on running the lidarslam launch file

Secondly, RVIZ shows absolutely no output. I see that some /map and /modified map is being published, but PointCloud2 is not visualizing it.

It seems the map frame is missing

The following shows the point cloud created by the lidar:

I am unsure as to what the issue is. Any help would be greatly appreciated.