Turtlesim Comms: Echo Messages on a Topic

Sometimes it may be useful to look at a topic’s published messages in real time. To do so, we can use the command rostopic echo. Let’s take a look at the /turtle1/cmd_vel topic.

$ rostopic echo /turtle1/cmd_vel

If we then command the turtle to move from the turtle_teleop_key window, we will be able to see the output message in real-time.