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Installing and Starting Gazebo

Installation

Install ROS and get the simulator_gazebo package by (%YOUR_ROS_DISTRO% can be { electric, fuerte, groovy`} etc.):

sudo apt-get install ros-%YOUR_ROS_DISTRO%-simulator-gazebo

Note: This does not work for the indigo distribution. Instead, try the following:

sudo apt-get install ros-indigo-simulators

Launching Gazebo

Setup ros environment variables:

source /opt/ros/%YOUR_ROS_DISTRO%/setup.bash

The standard Gazebo launch file is started using:

roslaunch gazebo_worlds empty_world.launch

Except in the case of Indigo, where the launch file is started using:

roslaunch gazebo_ros empty_world.launch

This should start the simulator and open up a GUI window that looks like this:

*see here for Box-Turtle GUI interaction keys.

If your system does not have sufficient graphics support, you can run gazebo headless.

Launch Script Explained

Looking at the gazebo_worlds/launch/empty_world.launch,

<launch>
  <!-- start gazebo with an empty plane -->
  <param name="/use_sim_time" value="true" />
  <node name="gazebo" pkg="gazebo" type="gazebo" args="$(find gazebo_worlds)/worlds/empty.world" respawn="false" output="screen"/>
</launch>

The script simply starts the Gazebo executable with a default world file (empty.world). The world file is where you can customize basic features of the simulator, such as physics engine parameters, ground plane textures, lighting and etc. For most users, the standard world file loaded by empty_world.launch should suffice. The ROS parameter /use_sim_time triggers ROS time to use the simulation time in the /clock ROS topic published by gazebo rather than the system wall clock time, see here for more details.

Next Tutorial: Spawn objects in the world