Refactor air pressure demo

ros_gz_sim_demos/CMakeLists.txt

@@ -9,6 +9,12 @@ if(BUILD_TESTING)
   ament_lint_auto_find_test_dependencies()
 endif()
 
+install(
+  DIRECTORY
+    config/
+  DESTINATION share/${PROJECT_NAME}/config
+)
+
 install(
   DIRECTORY
     launch/

ros_gz_sim_demos/README.md

@@ -14,7 +14,7 @@ There's a convenient launch file, try for example:
 
 Publishes fluid pressure readings.
 
-    ros2 launch ros_gz_sim_demos air_pressure.launch.py
+    ros2 launch ros_gz_sim_demos air_pressure.launch.xml
 
 This demo also shows the use of custom QoS parameters. The sensor data is
 published as as "best-effort", so trying to subscribe to "reliable" data won't

ros_gz_sim_demos/config/air_pressure.yaml

@@ -0,0 +1,6 @@
+# Air pressure bridge configuration.
+- topic_name: "air_pressure"
+  ros_type_name: "sensor_msgs/msg/FluidPressure"
+  gz_type_name: "gz.msgs.FluidPressure"
+  lazy: true
+  direction: GZ_TO_ROS

ros_gz_sim_demos/launch/air_pressure.launch.xml

@@ -0,0 +1,13 @@
+<launch>
+  <gz_server
+    world_sdf_file="sensors.sdf"
+    use_composition="True"
+    create_own_container="True" />
+  <ros_gz_bridge
+    bridge_name="ros_gz_bridge"
+    config_file="$(find-pkg-share ros_gz_sim_demos)/config/air_pressure.yaml"
+    use_composition="True"
+    bridge_params="'qos_overrides./air_pressure.publisher.reliability': 'best_effort'" />
+  <node pkg="rqt_topic" exec="rqt_topic" />
+  <executable cmd="gz sim -g" />
+</launch>