Lecture 4: ROS Topics - Ex. 2.5 "Age topic does not appear to be published yet"

Course Support ROS Basics In 5 Days (C++)
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After completing and making sure my code matched the solutions for exercise 2.5 in lecture 4 -understanding ROS topics. I compiled, sourced and launched my ros node successfully.

But when I tried to use “rostopic echo /Age” after launching my publisher, I got the message, ‘topic [/Age] does not appear to be published yet’.

Additionally, I did not get any errors at compilation, but VS code is giving and error on a few lines of my cpp file.

rostopicerror
rostopicerror977×633 53.3 KB

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I think I know what the issue is. I didn’t ‘print’ the topic with ROS_INFO

1 Like
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Hi @rmmilner,

In addition, Age is not a topic - it’s a custom message. Messages are published to topics.

From your code, the topic associated with Age is /age_info.

By the way, welcome to the Community!