Can;t work with 4.10

It has become sooooo frustrating… :frowning_face:
I have to do the following,…:
rostopic pub /[name_of_action_server]/goal /[type_of_the_message_used_by_the_topic] [TAB][TAB]

I am writing:
rostopic pub /ardone_action_server/goal /ardrone_as/ArdroneActionGoal … but pressing TAB TAB doenst give any autocomplete.
I have also tried:
rostopic pub /ardone_action_server/goal /ardrone_as/ArdroneGoal… but same! :frowning:

Plus what is the difference between ArdroneGoal and ArdroneActionGoal, please explain!
As in the lectures, first you said that message types are as ArdroneGoal, ArdroneReset, and at the end you said that the types are ArdroneActionGoal etc… sooooo confusingggggg… :frowning:

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Hi @syedsaadwaqar4,

I’m sorry about your confusion and frustration. But don’t worry, this sometimes happens with unfamiliar material and you will get over it soon - we’re here to help you do just that!

Now to your questions:

Please check the following:

  • Ensure the action server is running by starting it using the roslaunch command:
roslaunch ardrone_as action_server.launch
  • This command is not correct: rostopic pub /ardone_action_server/goal /ardrone_as/ArdroneActionGoal; it should be rostopic pub /ardone_action_server/goal ardrone_as/ArdroneActionGoal! Can you spot the difference :wink: ?

  • The right message to use here is ArdroneActionGoal, not ArdroneGoal, because you are working from the terminal.


    • You can already press TAB TAB when you have typed rostopic pub /ardone_action_server/goal . The message type will be completed for you.
    • Even by the time you have typed rostopic pub /ardone , you can press TAB TAB to get autocomplete or get some suggestions. Try pressing TAB TAB here and at other points along the way.
    • Enjoy autocomplete, fully!

As mentioned in the notes (you might have missed it):

  • ArdroneGoal is used in the code.
  • ArdroneActionGoal is used if you are working from the terminals.

Please let us know if this clears yours confusion or if you need further clarifications.


Why? Because the ROS people said so!


Thank you sir. It really helped! :slight_smile:

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