[tmp] correct env var

opennav_coverage_demo/launch/coverage_demo_launch.py

@@ -17,7 +17,13 @@
 
 from ament_index_python.packages import get_package_share_directory
 from launch import LaunchDescription
-from launch.actions import ExecuteProcess, IncludeLaunchDescription, OpaqueFunction, RegisterEventHandler
+from launch.actions import (
+    AppendEnvironmentVariable,
+    ExecuteProcess,
+    IncludeLaunchDescription,
+    OpaqueFunction,
+    RegisterEventHandler,
+)
 from launch.event_handlers import OnShutdown
 from launch.launch_description_sources import PythonLaunchDescriptionSource
 from launch_ros.actions import Node
@@ -64,6 +70,8 @@ def generate_launch_description():
         launch_arguments={"gz_args": ["-v4 -g "]}.items(),
     )
 
+    set_env_vars_resources = AppendEnvironmentVariable('GZ_SIM_RESOURCE_PATH',sim_dir)
+
     start_gazebo_spawner_cmd = IncludeLaunchDescription(
         PythonLaunchDescriptionSource(
             os.path.join(sim_dir, 'launch', 'spawn_tb3.launch.py')),
@@ -104,6 +112,7 @@ def generate_launch_description():
         output='screen')
 
     ld = LaunchDescription()
+    ld.add_action(set_env_vars_resources)
     ld.add_action(world_sdf_xacro)
     ld.add_action(remove_temp_sdf_file)
     ld.add_action(gazebo_server)