[Bug] UAV Model fails to sapwn in Gazebo with a custom world

mzahana commented 8 months ago

Describe the bug

I am using PX4 v1.14 and Gazebo garden. I am trying to simulate a quadcopter (e.g. x500) in a custom world. I plaved my custom world in Tools/simulation/gz/worlds directory. Then I used the command

PX4_GZ_WORLD=mountains make px4_sitl gz_x500

Gazebo opens up with the custom world. However, the x500 quadcopter is not spawned. I get the following output on the terminal

px4 starting.

INFO  [px4] startup script: /bin/sh etc/init.d-posix/rcS 0
INFO  [init] found model autostart file as SYS_AUTOSTART=4001
INFO  [param] selected parameter default file parameters.bson
INFO  [param] importing from 'parameters.bson'
INFO  [parameters] BSON document size 274 bytes, decoded 274 bytes (INT32:11, FLOAT:3)
INFO  [param] selected parameter backup file parameters_backup.bson
INFO  [dataman] data manager file './dataman' size is 7866640 bytes
INFO  [init] starting gazebo with world: /home/user/shared_volume/PX4-Autopilot/Tools/simulation/gz/worlds/mountains.sdf
WARN  [init] PX4_GZ_MODEL_NAME or PX4_GZ_MODEL not set using PX4_SIM_MODEL.
INFO  [gz_bridge] world: mountains, model name: x500_0, simulation model: x500
QStandardPaths: XDG_RUNTIME_DIR not set, defaulting to '/tmp/runtime-user'
libEGL warning: egl: failed to create dri2 screen
libEGL warning: egl: failed to create dri2 screen
ERROR [gz_bridge] Service call timed out
ERROR [gz_bridge] Task start failed (-1)
ERROR [init] gz_bridge failed to start
ERROR [px4] Startup script returned with return value: 256

NOTE I am running this setup inside a docker container.

The simulation works fine with the default world. The interesting thing is if I copy the content of my custom world into the world file named default.sdf and run the simulation with the x500 model and the default.sdf, the custom world works fine ! However, if I use any different world with a file name different than default.sdf, the world shows up in Gazebo, but the drone model fails to spawn!

To Reproduce

Clone the PX4-Autopilot repo and check out v1.14
Place a custom world model custom.sdf in PX4-Autopilot/Tools/simulation/gz/worlds/
run the simulation using PX4_GZ_WORLD=custom make px4_sitl gz_x500

Expected behavior

Gazebo runs with the custom world with the x500 model in it.

Screenshot / Media

No response

Flight Log

No logs as PX4 SITL fails to start

Software Version

All running inside a docker container

Ubuntu 22
PX4 v1.14
Gazebo garden

Flight controller

SITL

Vehicle type

Multicopter

How are the different components wired up (including port information)

No response

Additional context

No response

mzahana commented 8 months ago

@Jaeyoung-Lim any clue ?

dirksavage88 commented 8 months ago

@mzahana what does your custom world sdf look like? Are you including the following plugins?

<physics type="ode">
      <max_step_size>0.004</max_step_size>
      <real_time_factor>1.0</real_time_factor>
      <real_time_update_rate>250</real_time_update_rate>
    </physics>
    <plugin name='gz::sim::systems::Physics' filename='gz-sim-physics-system'/>
    <plugin name='gz::sim::systems::UserCommands' filename='gz-sim-user-commands-system'/>
    <plugin name='gz::sim::systems::SceneBroadcaster' filename='gz-sim-scene-broadcaster-system'/>
    <plugin name='gz::sim::systems::Contact' filename='gz-sim-contact-system'/>
    <plugin name='gz::sim::systems::Imu' filename='gz-sim-imu-system'/>
    <plugin name='gz::sim::systems::AirPressure' filename='gz-sim-air-pressure-system'/>
    <plugin name='gz::sim::systems::ApplyLinkWrench' filename='gz-sim-apply-link-wrench-system'/>
    <plugin name='gz::sim::systems::Sensors' filename='gz-sim-sensors-system'>
      <render_engine>ogre2</render_engine>
    </plugin>
    <gui fullscreen='false'>
      <plugin name='3D View' filename='GzScene3D'>
        <gz-gui>
          <title>3D View</title>
          <property type='bool' key='showTitleBar'>0</property>
          <property type='string' key='state'>docked</property>
        </gz-gui>
        <engine>ogre2</engine>
        <scene>scene</scene>
        <ambient_light>0.5984631152222222 0.5984631152222222 0.5984631152222222</ambient_light>
        <background_color>0.8984631152222222 0.8984631152222222 0.8984631152222222</background_color>
        <camera_pose>-6 0 6 0 0.5 0</camera_pose>
      </plugin>
      <plugin name='World control' filename='WorldControl'>
        <gz-gui>
          <title>World control</title>
          <property type='bool' key='showTitleBar'>0</property>
          <property type='bool' key='resizable'>0</property>
          <property type='double' key='height'>72</property>
          <property type='double' key='width'>121</property>
          <property type='double' key='z'>1</property>
          <property type='string' key='state'>floating</property>
          <anchors target='3D View'>
            <line own='left' target='left'/>
            <line own='bottom' target='bottom'/>
          </anchors>
        </gz-gui>
        <play_pause>1</play_pause>
        <step>1</step>
        <start_paused>1</start_paused>
      </plugin>
      <plugin name='World stats' filename='WorldStats'>
        <gz-gui>
          <title>World stats</title>
          <property type='bool' key='showTitleBar'>0</property>
          <property type='bool' key='resizable'>0</property>
          <property type='double' key='height'>110</property>
          <property type='double' key='width'>290</property>
          <property type='double' key='z'>1</property>
          <property type='string' key='state'>floating</property>
          <anchors target='3D View'>
            <line own='right' target='right'/>
            <line own='bottom' target='bottom'/>
          </anchors>
        </gz-gui>
        <sim_time>1</sim_time>
        <real_time>1</real_time>
        <real_time_factor>1</real_time_factor>
        <iterations>1</iterations>
      </plugin>
      <plugin name='Entity tree' filename='EntityTree'/>
    </gui>
    <gravity>0 0 -9.8</gravity>
    <magnetic_field>6e-06 2.3e-05 -4.2e-05</magnetic_field>
    <atmosphere type='adiabatic'/>
    <scene>
      <grid>false</grid>
      <ambient>0.4 0.4 0.4 1</ambient>
      <background>0.7 0.7 0.7 1</background>
      <shadows>true</shadows>
    </scene>

Also one thing I notice is a lot of the world files from the gazebo model repo don't include <world> tags on the sdf, so px4 sitl thinks it's a model and not a world.

mzahana commented 8 months ago

@dirksavage88 yes. If the same exact world is saved in a file named default.sdf it works. If it is saved with any other name (same content), it does not work.

frede791 commented 8 months ago

Hey @mzahana I might know why this is not working: When you name your world, the world name needs to match with the name of the file. So when you call your world mountains.sdf your world must have the name mountains. I suspect that since it works for default, your world is still named default. So to fix this just adjust the top of your file to look like:

<sdf version='1.9'>
  <world name='mountains'>
...

Let me know if this works! Otherwise, if you send me your file, I can take a closer look.

mzahana commented 7 months ago

@frede791 thanks !

How did I miss that! 😳 That solved it.

frede791 commented 7 months ago

It's not well established. I'll make a PR to better highlight this in the user guide. Glad I could be of help!

PX4 / PX4-Autopilot