title: How to install ROS on Ubuntu 18.04?
body: <p>Im running Ubuntu 18.04 and trying to install ROS for the first time on my machine. I have tried to follow the instructions at: <a href="http://wiki.ros.org/melodic/Installation/Ubuntu" rel="nofollow noreferrer">http://wiki.ros.org/melodic/Installation/Ubuntu</a></p>
  
  <p>I get stuck at this part.</p>
  
  <pre><code>sudo apt-get install ros-melodic-desktop-full
  </code></pre>
  
  <p>My attempts:</p>
  
  <pre><code>sudo apt -f install
  
  sudo apt update --fix-missing
  
  sudo dpkg --configure -a
  
  sudo dpkg --remove --force-remove--reinstreq
  
  sudo apt clean
  
  sudo apt update
  
  sudo rm /var/lib/apt/lists/lock
  
  sudo rm /var/cache/apt/archives/lock
  </code></pre>
  
  <p>Nothing has worked so far.</p>
  
  <p>Terminal commands:</p>
  
  <pre><code>$sudo apt-get install ros-melodic-desktop-full
  Reading package lists… Finished
  Builds dependency trees
  Reading state information ... Finished
  Some packages could not be installed. It may mean that you have requested
  an impossible situation or, if you use the unstable distribution
  that some necessary packages have not yet been created or moved
  from "Incoming".
  The following information may help to resolve the situation:
  
  The following packages have dependencies that cannot be satisfied:
   rose-melodic-desktop-full: Dependent on: rose-melodic-desktop but it will not be installed
                              Depending on: rose-melodic-perception but it will not be installed
                              Depending on: rose-melodic-simulators but it will not be installed
                              Depending on: ros-melodic-urdf-sim-tutorial but it will not be installed
  E: Could not correct the problems, you have withheld broken packages.
  
  </code></pre>
  
  <p>Please help me install ROS</p>