[Tutorial] Getting started with Gazebo in ROS

Run Gazebo

These three steps will run Gazebo with a default world.

1. Install Gazebo.

2. Open a terminal. On most Ubuntu systems you can press CTRL+ALT+t

3. Start Gazebo by entering the following at the command prompt.

   gazebo

Run Gazebo with a robot

Let's simulate something a bit more interesting by loading a world with a pioneer2dx.

1. Open a terminal and enter the following command.

   gazebo worlds/pioneer2dx.world

Where are the worlds located?

You may have noticed the mysterious worlds/pioneer2dx.world argument in the above command. This instructs gazebo to find the pioneer2dx.world file, and load it on start.

World files are located in a versioned system directory, for example /usr/share/gazebo-7 on Ubuntu. If you have Gazebo 7.0 installed on Ubuntu, in a terminal type the following to see a complete list of worlds.

ls /usr/share/gazebo-7/worlds

For a Gazebo 7.0 installation on OS X using Homebrew, type the following to see a complete list of worlds.

ls /usr/local/share/gazebo-7/worlds

Client and server separation

The gazebo command actually runs two different executables for you. The first is called gzserver, and the second gzclient.

The gzserver executable runs the physics update-loop and sensor data generation. This is the core of Gazebo, and can be used independently of a graphical interface. You may see the phrase "run headless" thrown about in the forums. This phrase equates to running only the gzserver. An example use case would involve running gzserver on a cloud computer where a user interface is not needed.

The gzclient executable runs a QT based user interface. This application provides a nice visualization of simulation, and convenient controls over various simulation properties.

Try running each of these executables. Open a terminal and run the server:

gzserver

Open another terminal and run the graphical client:

gzclient

At this point you should see the Gazebo user interface. You restart the gzclient application as often as you want, and even run multiple interfaces.

Reference:

Gazebo Tutorial: Quick Start