Add the ability to control the depth and reliability of the /scan topic

lidar/sllidar_ros2/launch/sllidar_a1_launch.py

@@ -18,6 +18,8 @@ def generate_launch_description():
     inverted = LaunchConfiguration('inverted', default='false')
     angle_compensate = LaunchConfiguration('angle_compensate', default='true')
     scan_mode = LaunchConfiguration('scan_mode', default='Sensitivity')
+    scan_qos_depth = LaunchConfiguration('scan_qos_depth', default='10')
+    scan_qos_reliability = LaunchConfiguration('scan_qos_reliability', default='reliable')
     
     return LaunchDescription([
 
@@ -55,17 +57,28 @@ def generate_launch_description():
             default_value=scan_mode,
             description='Specifying scan mode of lidar'),
 
+        DeclareLaunchArgument(
+            'scan_qos_depth',
+            default_value=scan_qos_depth,
+            description='Queue depth for the /scan publisher'),
+
+        DeclareLaunchArgument(
+            'scan_qos_reliability',
+            default_value=scan_qos_reliability,
+            description='Reliability policy for the /scan publisher: best_effort or reliable'),
 
         Node(
             package='sllidar_ros2',
             executable='sllidar_node',
             name='sllidar_node',
-            parameters=[{'channel_type':channel_type,
-                         'serial_port': serial_port, 
-                         'serial_baudrate': serial_baudrate, 
+            parameters=[{'channel_type': channel_type,
+                         'serial_port': serial_port,
+                         'serial_baudrate': serial_baudrate,
                          'frame_id': frame_id,
-                         'inverted': inverted, 
-                         'angle_compensate': angle_compensate}],
+                         'inverted': inverted,
+                         'angle_compensate': angle_compensate,
+                         'scan_qos_depth': scan_qos_depth,
+                         'scan_qos_reliability': scan_qos_reliability}],
             output='screen'),
     ])