How can I run this Gazebo simulation? The launch file is not seen as a launch file

edit

Firstly I'm really really new to ROS. I need to import this world and get it open in Gazebo for a simulation: (https://github.com/aws-robotics/aws-r...)

but when its time to launch I get the error that the launch file is not a launch file. So I wondered if I did the wrong steps before I can launch. I'm using ROS development studio for the terminal and Gazebo. So I tried with another project my co-worker sent me and it worked, here are the steps I took: 1. git clone the project into simulation_ws src 2. then go back to simulation_ws and enter "catkin_make" 3. then I enter "source devel/setup.bash" 4. then i enter roslaunch "file name" "launch file name" 5. Open Gazebo window where robot shows up

but this doesn't work with the project in the link above, so I must be missing something in the steps I took since I'm such a newbie. On the readme it says to include some code in the launch file but when you check one of them the line is already there so I've no idea what that means.

What do you all think?

*edit here is my input commands:

cd simulation_ws

cd src

git clone https://github.com/aws-robotics/aws-robomaker-hospital-world.git

cd ..

catkin_make

source devel.setup.bash

roslaunch aws-robomaker-hospital-world hospital.launch

the terminal output is:

RLException: [hospital.launch] is neither a launch file in package [aws-robomaker-hospital-world] nor is [aws-robomaker-hospital-world] a launch file name The traceback for the exception was written to the log file