In this chapter, we introduced the simulation environment of ROS called Gazebo, a standalone simulator that also provides full integration with ROS.
First, you learned about SDF, the standard XML format for robot simulation driven by Gazebo. SDF extends URDF and allows us to describe objects and environments for robot simulators, visualization, and control.
Following a parallel process to that of Chapter 4, Creating the Virtual Two-Wheeled ROS Robot, we produced a robot description within the ./urdf/gopigo.gazebo file. The simulation was then started by running ./launch/gopigo_gazebo.launch.
In this chapter, you were provided with an overview of how the Gazebo interface GUI is organized and performed some simple interactions with the GoPiGo3 model to see how it is affected by the gravity or the application of torque in the joint of one of its wheels.
By now, you should...