[learning] launch file from moveit2 tutorial [referenced from: https://www.notion.so/mightymjolnir/MIoveit2-temperory-note-5f57377d7f76445eb7d7ac2bd1d7840e]

demo.launch.py

import os
from launch import LaunchDescription
from launch.actions import DeclareLaunchArgument, OpaqueFunction
from launch.substitutions import LaunchConfiguration, PathJoinSubstitution
from launch.conditions import IfCondition, UnlessCondition
from launch_ros.actions import Node
from launch_ros.substitutions import FindPackageShare
from launch.actions import ExecuteProcess
from ament_index_python.packages import get_package_share_directory
from moveit_configs_utils import MoveItConfigsBuilder


def generate_launch_description():
    declared_arguments = []
    declared_arguments.append(
        DeclareLaunchArgument(
            "rviz_config",
            default_value="panda_moveit_config_demo.rviz",
            description="RViz configuration file",
        )
    )

    # OpaqueFunction is an action which calls a function whose 
    return LaunchDescription(
        declared_arguments + [OpaqueFunction(function=launch_setup)]
    )


def launch_setup(context, *args, **kwargs):
    moveit_config = (
        # load from package whose name is `moveit_resources_panda_moveit_config`
        MoveItConfigsBuilder("moveit_resources_panda")
        # Load robot description.
        .robot_description(file_path="config/panda.urdf.xacro")
        # Load trajectory execution and moveit controller managers' parameters
        .trajectory_execution(
            file_path="config/gripper_moveit_controllers.yaml"
        ).planning_scene_monitor(  # modify default settings
            publish_robot_description=True, publish_robot_description_semantic=True
        )
        # Load planning pipelines parameters from `config/xxx_planning.yaml`
        .planning_pipelines(
            pipelines=["ompl", "chomp", "pilz_industrial_motion_planner"]
        )
        # Get a `MoveItConfigs` instance with all parameters loaded.
        .to_moveit_configs()
    )  # brackets can me omitted actually

    # Start the actual move_group node/action server
    run_move_group_node = Node(
        package="moveit_ros_move_group",
        executable="move_group",
        output="screen",
        parameters=[moveit_config.to_dict()],
    )

    # retrieve "rviz_config" from launch_configurations, which may be set via CLI
    rviz_base = LaunchConfiguration("rviz_config")
    # find riviz config file `*.rviz` from share path of package `moveit2_tutorials`,
    # e.g. install/moveit2_tutorials/ashare/moveit2_tutorials/launch/
    rviz_config = PathJoinSubstitution(
        [FindPackageShare("moveit2_tutorials"), "launch", rviz_base]
    )

    # RViz
    rviz_node = Node(
        package="rviz2",
        executable="rviz2",
        name="rviz2",
        output="log",
        arguments=["-d", rviz_config],
        parameters=[
            moveit_config.robot_description,
            moveit_config.robot_description_semantic,
            moveit_config.robot_description_kinematics,
            moveit_config.planning_pipelines,
            moveit_config.joint_limits,
        ],
    )

    # Static TF
    static_tf = Node(
        package="tf2_ros",
        executable="static_transform_publisher",
        name="static_transform_publisher",
        output="log",
        arguments=["0.0", "0.0", "0.0", "0.0", "0.0", "0.0", "world", "panda_link0"],
    )

    # Publish TF
    robot_state_publisher = Node(
        package="robot_state_publisher",
        executable="robot_state_publisher",
        name="robot_state_publisher",
        output="both",
        parameters=[moveit_config.robot_description],
    )

    # ros2_control using FakeSystem as hardware
    # it's `config/ros2_controllers.yaml` in package `moveit_resources_panda_moveit_config`
    ros2_controllers_path = os.path.join(
        get_package_share_directory("moveit_resources_panda_moveit_config"),
        "config",
        "ros2_controllers.yaml",
    )
    ros2_control_node = Node(
        package="controller_manager",
        executable="ros2_control_node",
        parameters=[moveit_config.robot_description, ros2_controllers_path],
        output="both",
    )
    # publish joint states
    joint_state_broadcaster_spawner = Node(
        package="controller_manager",
        executable="spawner",
        arguments=[
            "joint_state_broadcaster",
            "--controller-manager-timeout",
            "300",
            "--controller-manager",
            "/controller_manager",
        ],
    )
    # load controllers
    arm_controller_spawner = Node(
        package="controller_manager",
        executable="spawner",
        arguments=["panda_arm_controller", "-c", "/controller_manager"],
    )

    hand_controller_spawner = Node(
        package="controller_manager",
        executable="spawner",
        arguments=["panda_hand_controller", "-c", "/controller_manager"],
    )
    nodes_to_start = [
        rviz_node,
        static_tf,
        robot_state_publisher,
        run_move_group_node,
        ros2_control_node,
        joint_state_broadcaster_spawner,
        arm_controller_spawner,
        hand_controller_spawner,
    ]

    return nodes_to_start

ros2_controllers.yaml

# This config file is used by ros2_control
controller_manager:
  ros__parameters:
    update_rate: 100  # Hz

    panda_arm_controller:
      type: joint_trajectory_controller/JointTrajectoryController

    panda_hand_controller:
      type: position_controllers/GripperActionController

    joint_state_broadcaster:
      type: joint_state_broadcaster/JointStateBroadcaster


panda_arm_controller:
  ros__parameters:
    command_interfaces:
      - position
    state_interfaces:
      - position
      - velocity
    joints:
      - panda_joint1
      - panda_joint2
      - panda_joint3
      - panda_joint4
      - panda_joint5
      - panda_joint6
      - panda_joint7

panda_hand_controller:
  ros__parameters:
    joint: panda_finger_joint1