Error mgs during multi vehicle simulation

1

I followed the instruction as mentioned here:-
https://dev.px4.io/en/simulation/multi-vehicle-simulation.html
when I run launch file

roslaunch px4 multi_uav_mavros_sitl.launch

works fine for default programme but when I added code for one more drone (UAV1 iris_3) and run

roslaunch px4 multi_uav_mavros_sitl.launch

I get following error message although I can see UAVs in Gazebo simulator.

[multi_uav_mavros_sitl.launch] is neither a launch file in package [px4] nor is [px4] a launch file name
The traceback for the exception was written to the log file.

here is the code which I added for 3rd UAV inside launch file:-

<group ns="uav3">
    <arg name="fcu_url" default="udp://:14543@localhost:14558"/>
    <arg name="gcs_url" value=""/>
    <arg name="tgt_system" value="3"/> 
    <arg name="tgt_component" value="1"/>
    <arg name="rcS3" default="$(find px4)/posix-configs/SITL/init/$(arg est)/$(arg vehicle)_3"/>
    <arg name="ID" value="3"/>
    <include file="$(find px4)/launch/single_vehcile_spawn.launch">
        <arg name="x" value="1"/>
        <arg name="y" value="1"/>
        <arg name="z" value="0"/>
        <arg name="R" value="0"/>
        <arg name="P" value="0"/>
        <arg name="Y" value="0"/>
        <arg name="vehicle" value="$(arg vehicle)"/>
        <arg name="rcS" value="$(arg rcS3)"/>
        <arg name="mavlink_udp_port" value="14563"/>
        <arg name="ID" value="$(arg ID)"/>
    </include>

    <include file="$(find mavros)/launch/node.launch">
        <arg name="pluginlists_yaml" value="$(arg pluginlists_yaml)" />
        <arg name="config_yaml" value="$(arg config_yaml)" />

        <arg name="fcu_url" value="$(arg fcu_url)" />
        <arg name="gcs_url" value="$(arg gcs_url)" />
        <arg name="tgt_system" value="$(arg tgt_system)" />
        <arg name="tgt_component" value="$(arg tgt_component)" />
    </include>
</group>
2

I don’t know the reason but If I run that command inside firmware directory It runs successfully and other than that It gives that error

3

If you can fully describe how you setup your environment and try this with the current launch file on the master branch, I can try to figure this out.

4

I installed px4:-

mkdir -p ~/src
cd ~/src
git clone https://github.com/PX4/Firmware.git
cd Firmware
git submodule update --init --recursive

I run updated launch file. It runs inside Firmware directory but gives the same error if I try to run from different directories.

5

What did you do after that code snippet? i.e between git submodule update --init --recursive and roslaunch px4 multi_uav_mavros_sitl.launch, source and setting env variable commands?

6

Yes, I source the env and set variable every time before I run launch file.

7

I can’t reproduce this without a complete list of the commands you’re using.

8

Here is what I am doing which works fine:

cd Firmware_clone
git submodule update --init --recursive
source Tools/setup_gazebo.bash $(pwd) $(pwd)/build/posix_sitl_default
export ROS_PACKAGE_PATH=$ROS_PACKAGE_PATH:$(pwd):$(pwd)/Tools/sitl_gazebo
roslaunch px4 multi_uav_mavros_sitl.launch

but I run the last command (launch file) even for 2 UAV (default case) from other the directory I am getting that error.

9

Did you build SITL?

cd Firmware_clone
git submodule update --init --recursive

> make posix_sitl_default sitl_gazebo`

source Tools/setup_gazebo.bash $(pwd) $(pwd)/build/posix_sitl_default
export ROS_PACKAGE_PATH=$ROS_PACKAGE_PATH:$(pwd):$(pwd)/Tools/sitl_gazebo
roslaunch px4 multi_uav_mavros_sitl.launch
10

Yes tried with building SITL.

11

Actually, according to Update multi-vehicle-simulation.md by lamping7 · Pull Request #473 · PX4/PX4-Devguide · GitHub you need both these lines because the sitl_gazebo target doesn’t build SITL itself.

make posix_sitl_default
make posix_sitl_default sitl_gazebo

12

I run complete sequence of command this time including both commands (suggested by you) but got same problem and for

make posix_sitl_default

I got

ninja: no work to do.