Download the package inside catkin_ws/src. Then put the follow commands:
cd
cd .gazebo/models
cp -r /home/user/catkin_ws/src/basic_amr/labyrinth .
cd
chmod u+x ./catkin_ws/src/basic_amr/basic_amr_description/src/tf_basic_amr.py
Then, you can simulate the robot in gazebo inside a labyrinth with the following command:
roslaunch basic_amr_gazebo basic_amr_empty_world.launch
Also, you can simulate the robot in gazebo inside a labyrinth with the following command:
roslaunch basic_amr_gazebo basic_amr_labyrinth.launch