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Chatter Concert
Description: An example concert demonstration, talker-listener style.Keywords: concert
Tutorial Level: BEGINNER
Next Tutorial: Turtle Concert
Installation
Follow the rocon installation instructions.
Demo
Bootstrapping
Let's bootstrap all the robots as well as the centralised concert master. Source your setup.bash and rocon_launch the concert, e.g. for a source install:
> cd ~/concert/devel > source setup.bash > rocon_launch chatter_concert chatter.concert --screen
Auto-Start
This launches the concert solution, robot apps and immediately links everything once all the components are discovered.
Visualising
Open a shell, set ROS_MASTER_URI to localhost with a port number between 11311 and 11314 and run:
> rocon_gateway_graph
You'll notice four masters - the concert, dudette and two dudes. Dudette and the dudes flip your usual chatter pubs and subs (dudes of course have to listen to dudette, so they flip the subscribers and dudette flips the publisher).
You'll also notice that some of the masters are postfixed with uuid strings (the dudes). This is the default behaviour for naming and ensures that each member in the concert is unqiue. It can be overridden and will subsequently rely on the developer to ensure that each member has a unique name by passing the disable_uuid arg through to the underlying concert client/conductor launchers. This has been done for both dudette and the concert masters.
