The Iris_arducopter_runway.world exists and has been set to path but still when command -” gazebo –verbose ~/ardupilot_gazebo/worlds/iris_arducopter_runway.world” is given it opens an empty.world. This is my log….
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Gazebo multi-robot simulator, version 11.10.2
Copyright (C) 2012 Open Source Robotics Foundation.
Released under the Apache 2 License.
http://gazebosim.org

[Msg] Waiting for master.
Gazebo multi-robot simulator, version 11.10.2
Copyright (C) 2012 Open Source Robotics Foundation.
Released under the Apache 2 License.
http://gazebosim.org

[Msg] Waiting for master.
[Msg] Connected to gazebo master @ http://127.0.0.1:11345
[Msg] Publicized address: 192.168.0.189
[Wrn] [SystemPaths.cc:459] File or path does not exist         

[“/root/ardupilot_gazebo/worlds/iris_arducopter_runway.world”] [/root/ardupilot_gazebo/worlds/iris_arducopter_runway.world]
[Err] [Server.cc:472] Could not open file[/root/ardupilot_gazebo/worlds/iris_arducopter_runway.world]
[Wrn] [Server.cc:381] Falling back on worlds/empty.world
[Msg] Connected to gazebo master @ http://127.0.0.1:11345
[Msg] Publicized address: 192.168.0.189
[Msg] Loading world file [/usr/share/gazebo-11/worlds/empty.world]
shared memfd open() failed: Function not implemented
shared memfd open() failed: Function not implemented
ALSA lib confmisc.c:855:(parse_card) cannot find card ‘0’
ALSA lib conf.c:5178:(_snd_config_evaluate) function snd_func_card_inum returned error: No such file or directory
ALSA lib confmisc.c:422:(snd_func_concat) error evaluating strings
ALSA lib conf.c:5178:(_snd_config_evaluate) function snd_func_concat returned error: No such file or directory
ALSA lib confmisc.c:1334:(snd_func_refer) error evaluating name
ALSA lib conf.c:5178:(_snd_config_evaluate) function snd_func_refer returned error: No such file or directory
ALSA lib conf.c:5701:(snd_config_expand) Evaluate error: No such file or directory
ALSA lib pcm.c:2664:(snd_pcm_open_noupdate) Unknown PCM default
AL lib: (EE) ALCplaybackAlsa_open: Could not open playback device ‘default’: No such file or directory
[Err] [OpenAL.cc:84] Unable to open audio device[default]
Audio will be disabled.
[Wrn] [GuiIface.cc:120] QStandardPaths: XDG_RUNTIME_DIR not set, defaulting to ‘/tmp/runtime-root’
[Wrn] [Publisher.cc:135] Queue limit reached for topic /gazebo/default/user_camera/pose, deleting messag
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I expected the Iris_arducopter_runway.world file to be recognized and opened.