Hands-On ROS for Robotics Programming

Adding the controller to the Gazebo model of the robot

Here, we are going to use a mechanism called controller to transform speed /cmd_vel messages into motions for the left and right wheels of the robot. For the case of a two-wheeled robot, this is known as a differential drive controller. This name is due to the fact that straight paths are achieved by rotating the wheels at the same speed. Any difference between the left and right angular speeds will make the robot describe a circumferential path. The larger the difference, the lower the radius of such a circumference (a straight path corresponds to describing a sector of a circumference of infinite radius, that is, the infinitesimal speed difference between wheels).

Let's get to the practical ...