[Fix] Cleanup Launch Files

example_1/bringup/launch/test_forward_position_controller.launch.py

@@ -13,28 +13,24 @@
 # limitations under the License.
 
 from launch import LaunchDescription
-from launch.substitutions import PathJoinSubstitution
+from launch.substitutions import PathSubstitution
 from launch_ros.actions import Node
 from launch_ros.substitutions import FindPackageShare
 
 
 def generate_launch_description():
 
-    position_goals = PathJoinSubstitution(
-        [
-            FindPackageShare("ros2_control_demo_example_1"),
-            "config",
-            "rrbot_forward_position_publisher.yaml",
-        ]
-    )
-
     return LaunchDescription(
         [
             Node(
                 package="ros2_controllers_test_nodes",
                 executable="publisher_forward_position_controller",
                 name="publisher_forward_position_controller",
-                parameters=[position_goals],
+                parameters=[
+                    PathSubstitution(FindPackageShare("ros2_control_demo_example_1"))
+                    / "config"
+                    / "rrbot_forward_position_publisher.yaml"
+                ],
                 output="both",
             )
         ]

example_1/bringup/launch/test_joint_trajectory_controller.launch.py

@@ -13,28 +13,24 @@
 # limitations under the License.
 
 from launch import LaunchDescription
-from launch.substitutions import PathJoinSubstitution
+from launch.substitutions import PathSubstitution
 from launch_ros.actions import Node
 from launch_ros.substitutions import FindPackageShare
 
 
 def generate_launch_description():
 
-    position_goals = PathJoinSubstitution(
-        [
-            FindPackageShare("ros2_control_demo_example_1"),
-            "config",
-            "rrbot_joint_trajectory_publisher.yaml",
-        ]
-    )
-
     return LaunchDescription(
         [
             Node(
                 package="ros2_controllers_test_nodes",
                 executable="publisher_joint_trajectory_controller",
                 name="publisher_joint_trajectory_controller",
-                parameters=[position_goals],
+                parameters=[
+                    PathSubstitution(FindPackageShare("ros2_control_demo_example_1"))
+                    / "config"
+                    / "rrbot_joint_trajectory_publisher.yaml"
+                ],
                 output="both",
             )
         ]

example_1/description/launch/view_robot.launch.py

@@ -15,97 +15,83 @@
 from launch import LaunchDescription
 from launch.actions import DeclareLaunchArgument
 from launch.conditions import IfCondition
-from launch.substitutions import Command, FindExecutable, LaunchConfiguration, PathJoinSubstitution
+from launch.substitutions import Command, LaunchConfiguration, PathSubstitution
 
 from launch_ros.actions import Node
 from launch_ros.substitutions import FindPackageShare
 
 
 def generate_launch_description():
-    # Declare arguments
-    declared_arguments = []
-    declared_arguments.append(
-        DeclareLaunchArgument(
-            "description_package",
-            default_value="ros2_control_demo_description",
-            description="Description package with robot URDF/xacro files. Usually the argument \
-        is not set, it enables use of a custom description.",
-        )
-    )
-    declared_arguments.append(
-        DeclareLaunchArgument(
-            "description_file",
-            default_value="rrbot.urdf.xacro",
-            description="URDF/XACRO description file with the robot.",
-        )
-    )
-    declared_arguments.append(
-        DeclareLaunchArgument(
-            "gui",
-            default_value="true",
-            description="Start Rviz2 and Joint State Publisher gui automatically \
-        with this launch file.",
-        )
-    )
-    declared_arguments.append(
-        DeclareLaunchArgument(
-            "prefix",
-            default_value='""',
-            description="Prefix of the joint names, useful for \
-        multi-robot setup. If changed than also joint names in the controllers' configuration \
-        have to be updated.",
-        )
-    )
-
-    # Initialize Arguments
-    description_package = LaunchConfiguration("description_package")
-    description_file = LaunchConfiguration("description_file")
-    gui = LaunchConfiguration("gui")
-    prefix = LaunchConfiguration("prefix")
-
-    # Get URDF via xacro
-    robot_description_content = Command(
+    return LaunchDescription(
         [
-            PathJoinSubstitution([FindExecutable(name="xacro")]),
-            " ",
-            PathJoinSubstitution(
-                [FindPackageShare("ros2_control_demo_example_1"), "urdf", description_file]
+            DeclareLaunchArgument(
+                "description_package",
+                default_value="ros2_control_demo_description",
+                description=(
+                    "Description package with robot URDF/xacro files. Usually the argument "
+                    "is not set, it enables use of a custom description."
+                ),
+            ),
+            DeclareLaunchArgument(
+                "description_file",
+                default_value="rrbot.urdf.xacro",
+                description="URDF/XACRO description file with the robot.",
+            ),
+            DeclareLaunchArgument(
+                "gui",
+                default_value="true",
+                description=(
+                    "Start Rviz2 and Joint State Publisher gui automatically "
+                    "with this launch file."
+                ),
+            ),
+            DeclareLaunchArgument(
+                "prefix",
+                default_value='""',
+                description=(
+                    "Prefix of the joint names, useful for "
+                    "multi-robot setup. If changed than also joint names in the controllers' configuration "
+                    "have to be updated."
+                ),
+            ),
+            Node(
+                package="joint_state_publisher_gui",
+                executable="joint_state_publisher_gui",
+                condition=IfCondition(LaunchConfiguration("gui")),
+            ),
+            Node(
+                package="robot_state_publisher",
+                executable="robot_state_publisher",
+                output="both",
+                parameters=[
+                    {
+                        "robot_description": Command(
+                            [
+                                "xacro",
+                                " ",
+                                PathSubstitution(FindPackageShare("ros2_control_demo_example_1"))
+                                / "urdf"
+                                / LaunchConfiguration("description_file"),
+                                " ",
+                                "prefix:=",
+                                LaunchConfiguration("prefix"),
+                            ]
+                        )
+                    }
+                ],
+            ),
+            Node(
+                package="rviz2",
+                executable="rviz2",
+                name="rviz2",
+                output="log",
+                arguments=[
+                    "-d",
+                    PathSubstitution(FindPackageShare(LaunchConfiguration("description_package")))
+                    / "rrbot/rviz"
+                    / "rrbot.rviz",
+                ],
+                condition=IfCondition(LaunchConfiguration("gui")),
             ),
-            " ",
-            "prefix:=",
-            prefix,
         ]
     )
-    robot_description = {"robot_description": robot_description_content}
-
-    rviz_config_file = PathJoinSubstitution(
-        [FindPackageShare(description_package), "rrbot/rviz", "rrbot.rviz"]
-    )
-
-    joint_state_publisher_node = Node(
-        package="joint_state_publisher_gui",
-        executable="joint_state_publisher_gui",
-        condition=IfCondition(gui),
-    )
-    robot_state_publisher_node = Node(
-        package="robot_state_publisher",
-        executable="robot_state_publisher",
-        output="both",
-        parameters=[robot_description],
-    )
-    rviz_node = Node(
-        package="rviz2",
-        executable="rviz2",
-        name="rviz2",
-        output="log",
-        arguments=["-d", rviz_config_file],
-        condition=IfCondition(gui),
-    )
-
-    nodes = [
-        joint_state_publisher_node,
-        robot_state_publisher_node,
-        rviz_node,
-    ]
-
-    return LaunchDescription(declared_arguments + nodes)