navigation_launch.py

# Copyright (c) 2018 Intel Corporation
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
#     http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
 
import os
 
from ament_index_python.packages import get_package_share_directory
 
from launch import LaunchDescription
from launch.actions import DeclareLaunchArgument, GroupAction, SetEnvironmentVariable
from launch.conditions import IfCondition
from launch.substitutions import LaunchConfiguration, PythonExpression
from launch_ros.actions import LoadComposableNodes, SetParameter
from launch_ros.actions import Node
from launch_ros.descriptions import ComposableNode, ParameterFile
from nav2_common.launch import RewrittenYaml
 
 
def generate_launch_description():
    # Get the launch directory
    bringup_dir = get_package_share_directory('nav2_bringup')
 
    namespace = LaunchConfiguration('namespace')
    use_sim_time = LaunchConfiguration('use_sim_time')
    autostart = LaunchConfiguration('autostart')
    params_file = LaunchConfiguration('params_file')
    use_composition = LaunchConfiguration('use_composition')
    container_name = LaunchConfiguration('container_name')
    container_name_full = (namespace, '/', container_name)
    use_respawn = LaunchConfiguration('use_respawn')
    log_level = LaunchConfiguration('log_level')
 
    lifecycle_nodes = [
        'controller_server',
        'smoother_server',
        'planner_server',
        'behavior_server',
        'velocity_smoother',
        'collision_monitor',
        'bt_navigator',
        'waypoint_follower',
        'docking_server',
    ]
 
    # Map fully qualified names to relative ones so the node's namespace can be prepended.
    # In case of the transforms (tf), currently, there doesn't seem to be a better alternative
    # https://github.com/ros/geometry2/issues/32
    # https://github.com/ros/robot_state_publisher/pull/30
    # TODO(orduno) Substitute with `PushNodeRemapping`
    #              https://github.com/ros2/launch_ros/issues/56
    remappings = [('/tf', 'tf'), ('/tf_static', 'tf_static')]
 
    # Create our own temporary YAML files that include substitutions
    param_substitutions = {'autostart': autostart}
 
    configured_params = ParameterFile(
        RewrittenYaml(
            source_file=params_file,
            root_key=namespace,
            param_rewrites=param_substitutions,
            convert_types=True,
        ),
        allow_substs=True,
    )
 
    stdout_linebuf_envvar = SetEnvironmentVariable(
        'RCUTILS_LOGGING_BUFFERED_STREAM', '1'
    )
 
    declare_namespace_cmd = DeclareLaunchArgument(
        'namespace', default_value='', description='Top-level namespace'
    )
 
    declare_use_sim_time_cmd = DeclareLaunchArgument(
        'use_sim_time',
        default_value='false',
        description='Use simulation (Gazebo) clock if true',
    )
 
    declare_params_file_cmd = DeclareLaunchArgument(
        'params_file',
        default_value=os.path.join(bringup_dir, 'params', 'nav2_params.yaml'),
        description='Full path to the ROS2 parameters file to use for all launched nodes',
    )
 
    declare_autostart_cmd = DeclareLaunchArgument(
        'autostart',
        default_value='true',
        description='Automatically startup the nav2 stack',
    )
 
    declare_use_composition_cmd = DeclareLaunchArgument(
        'use_composition',
        default_value='False',
        description='Use composed bringup if True',
    )
 
    declare_container_name_cmd = DeclareLaunchArgument(
        'container_name',
        default_value='nav2_container',
        description='the name of conatiner that nodes will load in if use composition',
    )
 
    declare_use_respawn_cmd = DeclareLaunchArgument(
        'use_respawn',
        default_value='False',
        description='Whether to respawn if a node crashes. Applied when composition is disabled.',
    )
 
    declare_log_level_cmd = DeclareLaunchArgument(
        'log_level', default_value='info', description='log level'
    )
 
    load_nodes = GroupAction(
        condition=IfCondition(PythonExpression(['not ', use_composition])),
        actions=[
            SetParameter('use_sim_time', use_sim_time),
            Node(
                package='nav2_controller',
                executable='controller_server',
                output='screen',
                respawn=use_respawn,
                respawn_delay=2.0,
                parameters=[configured_params],
                arguments=['--ros-args', '--log-level', log_level],
                remappings=remappings + [('cmd_vel', 'cmd_vel_nav')],
            ),
            Node(
                package='nav2_smoother',
                executable='smoother_server',
                name='smoother_server',
                output='screen',
                respawn=use_respawn,
                respawn_delay=2.0,
                parameters=[configured_params],
                arguments=['--ros-args', '--log-level', log_level],
                remappings=remappings,
            ),
            Node(
                package='nav2_planner',
                executable='planner_server',
                name='planner_server',
                output='screen',
                respawn=use_respawn,
                respawn_delay=2.0,
                parameters=[configured_params],
                arguments=['--ros-args', '--log-level', log_level],
                remappings=remappings,
            ),
            Node(
                package='nav2_behaviors',
                executable='behavior_server',
                name='behavior_server',
                output='screen',
                respawn=use_respawn,
                respawn_delay=2.0,
                parameters=[configured_params],
                arguments=['--ros-args', '--log-level', log_level],
                remappings=remappings + [('cmd_vel', 'cmd_vel_nav')],
            ),
            Node(
                package='nav2_bt_navigator',
                executable='bt_navigator',
                name='bt_navigator',
                output='screen',
                respawn=use_respawn,
                respawn_delay=2.0,
                parameters=[configured_params],
                arguments=['--ros-args', '--log-level', log_level],
                remappings=remappings,
            ),
            Node(
                package='nav2_waypoint_follower',
                executable='waypoint_follower',
                name='waypoint_follower',
                output='screen',
                respawn=use_respawn,
                respawn_delay=2.0,
                parameters=[configured_params],
                arguments=['--ros-args', '--log-level', log_level],
                remappings=remappings,
            ),
            Node(
                package='nav2_velocity_smoother',
                executable='velocity_smoother',
                name='velocity_smoother',
                output='screen',
                respawn=use_respawn,
                respawn_delay=2.0,
                parameters=[configured_params],
                arguments=['--ros-args', '--log-level', log_level],
                remappings=remappings
                + [('cmd_vel', 'cmd_vel_nav')],
            ),
            Node(
                package='nav2_collision_monitor',
                executable='collision_monitor',
                name='collision_monitor',
                output='screen',
                respawn=use_respawn,
                respawn_delay=2.0,
                parameters=[configured_params],
                arguments=['--ros-args', '--log-level', log_level],
                remappings=remappings,
            ),
            Node(
                package='opennav_docking',
                executable='opennav_docking',
                name='docking_server',
                output='screen',
                respawn=use_respawn,
                respawn_delay=2.0,
                parameters=[configured_params],
                arguments=['--ros-args', '--log-level', log_level],
                remappings=remappings,
            ),
            Node(
                package='nav2_lifecycle_manager',
                executable='lifecycle_manager',
                name='lifecycle_manager_navigation',
                output='screen',
                arguments=['--ros-args', '--log-level', log_level],
                parameters=[{'autostart': autostart}, {'node_names': lifecycle_nodes}],
            ),
        ],
    )
 
    load_composable_nodes = GroupAction(
        condition=IfCondition(use_composition),
        actions=[
            SetParameter('use_sim_time', use_sim_time),
            LoadComposableNodes(
                target_container=container_name_full,
                composable_node_descriptions=[
                    ComposableNode(
                        package='nav2_controller',
                        plugin='nav2_controller::ControllerServer',
                        name='controller_server',
                        parameters=[configured_params],
                        remappings=remappings + [('cmd_vel', 'cmd_vel_nav')],
                    ),
                    ComposableNode(
                        package='nav2_smoother',
                        plugin='nav2_smoother::SmootherServer',
                        name='smoother_server',
                        parameters=[configured_params],
                        remappings=remappings,
                    ),
                    ComposableNode(
                        package='nav2_planner',
                        plugin='nav2_planner::PlannerServer',
                        name='planner_server',
                        parameters=[configured_params],
                        remappings=remappings,
                    ),
                    ComposableNode(
                        package='nav2_behaviors',
                        plugin='behavior_server::BehaviorServer',
                        name='behavior_server',
                        parameters=[configured_params],
                        remappings=remappings + [('cmd_vel', 'cmd_vel_nav')],
                    ),
                    ComposableNode(
                        package='nav2_bt_navigator',
                        plugin='nav2_bt_navigator::BtNavigator',
                        name='bt_navigator',
                        parameters=[configured_params],
                        remappings=remappings,
                    ),
                    ComposableNode(
                        package='nav2_waypoint_follower',
                        plugin='nav2_waypoint_follower::WaypointFollower',
                        name='waypoint_follower',
                        parameters=[configured_params],
                        remappings=remappings,
                    ),
                    ComposableNode(
                        package='nav2_velocity_smoother',
                        plugin='nav2_velocity_smoother::VelocitySmoother',
                        name='velocity_smoother',
                        parameters=[configured_params],
                        remappings=remappings
                        + [('cmd_vel', 'cmd_vel_nav')],
                    ),
                    ComposableNode(
                        package='nav2_collision_monitor',
                        plugin='nav2_collision_monitor::CollisionMonitor',
                        name='collision_monitor',
                        parameters=[configured_params],
                        remappings=remappings,
                    ),
                    ComposableNode(
                        package='opennav_docking',
                        plugin='opennav_docking::DockingServer',
                        name='docking_server',
                        parameters=[configured_params],
                        remappings=remappings,
                    ),
                    ComposableNode(
                        package='nav2_lifecycle_manager',
                        plugin='nav2_lifecycle_manager::LifecycleManager',
                        name='lifecycle_manager_navigation',
                        parameters=[
                            {'autostart': autostart, 'node_names': lifecycle_nodes}
                        ],
                    ),
                ],
            ),
        ],
    )
 
    # Create the launch description and populate
    ld = LaunchDescription()
 
    # Set environment variables
    ld.add_action(stdout_linebuf_envvar)
 
    # Declare the launch options
    ld.add_action(declare_namespace_cmd)
    ld.add_action(declare_use_sim_time_cmd)
    ld.add_action(declare_params_file_cmd)
    ld.add_action(declare_autostart_cmd)
    ld.add_action(declare_use_composition_cmd)
    ld.add_action(declare_container_name_cmd)
    ld.add_action(declare_use_respawn_cmd)
    ld.add_action(declare_log_level_cmd)
    # Add the actions to launch all of the navigation nodes
    ld.add_action(load_nodes)
    ld.add_action(load_composable_nodes)
 
    return ld