Okay, so we are done with simulating a complete robotic car in Gazebo; now, let's move the robot around the environment. We can do this using a keyboard_teleop node.

We can launch an existing TurtleBot teleop node using the following command:

$ roslaunch turtlebot_teleop keyboard_teleop.launch 

The TurtleBot teleop node is publishing Twist messages to /cmd_vel_mux/input/teleop, and we need to convert them into /catvehicle/cmd_vel.

The following command can do this conversion:

$ rosrun topic_tools relay /cmd_vel_mux/input/teleop /catvehicle/cmd_vel 

Now, you can move the car around the environment using the keyboard. This will be useful while we perform SLAM. Let's now run hector SLAM using a robotic car.