Facing problem during simulation on gazebo.

Hi I am trying to simulate this problem https://www.mathworks.com/matlabcentral/fileexchange/64381-matlab-and-simulink-robotics-arena-simulating-quadcopter-missions I have tried virtual box then VMware and after that I have download the files from this link https://www.mathworks.com/support/product/robotics/ros2-vm-installation-instructions-v5.html now the problem I am facing in all these cases is same when I run my simulation in gazebo I am facing errors in importing drone into the world loaded in my scenario. I have already connected simulink with ROS and works fine but my errors come in linux terminal.

Note: I have already followed steps according to documentation provided and tried videos too available on youtube and matlab platform. I have tried diffrent versions of ROS including latest version also ( ROS Noetic Humble Gazebo 11 and ROS Melodic Dashing Gazebov9 ) in a hope maybe old version might help me out in this problem but the error is consistent no matter what I try.

The Error I am facing are of the sort:

1. qws.urdf file is empty.
2. [INFO] [1723726120.533970, 0.000000]: Calling service /gazebo/spawn_urdf_model Service call failed: service [/gazebo/spawn_urdf_model] responded with an error: [ERROR] [1723726120.622680, 65.204000]: Spawn service failed. Exiting.
3. xacro: in-order processing became default in ROS Melodic. You can drop the option. resource not found: imav_2017 ROS path [0]=/opt/ros/melodic/share/ros ROS path [1]=/opt/ros/melodic/share when processing file: quadrotor.urdf.xacro [INFO] [1723726204.610146, 0.000000]: Loading model XML from file qws.urdf [ERROR] [1723726204.611562, 0.000000]: Error: file qws.urdf is empty

Answer 1

[Kothuri]

Hi Haroon Bangash ,

I understand that you are trying to run the File Exchange model and you are facing the errors when importing drone into the world loaded in the scenario.

• The error “qws.urdf file is empty” indicates that the URDF file you’re trying to load is either empty or not correctly formatted. Make sure that the URDF file contains valid XML content and is not empty. And Check the paths specified in the .xacro files and ensure they are correct and accessible.
• The error “resource not found: imav_2017” suggests that the required resource is missing. This could be due to incorrect paths or missing packages. Make sure that all necessary packages and resources are correctly installed and accessible.
• The error “service [/gazebo/spawn_urdf_model] responded with an error” indicates that the service call to spawn the URDF model in Gazebo is failing. This could be due to the configuration problems.

Make sure that all required ROS packages are installed.

You can refer the below documentation link for more info on Gazebo Simulation for Robotics System Toolbox:

https://www.mathworks.com/help/robotics/ug/gazebo-simulation-for-robotics-system.html

I hope this helps!