Question on Unit-3-topics - Not able to deploy Topic "/counter"

Course Support ROS2 In 5 Days Python
1

Hi,

  1. I followed the exercise and deployed all the steps including, creating launch file, making the file executable, etc. I don’t get any error in any step, however i dont see the topic “/counter” . The output of “ros2 topic list | grep ‘/counter’” does not show “/counter” but it has other topics from previous units. Does anything missing in the exercises/unit? Please help.
  2. Also, do you recommend any book to get better at C++ coding for robotics. I’m beginner in C++ programming and your examples are little over my head in terms of picking up programing concepts. please suggest.
2

Hi,

  1. Make sure you follow the steps from the previous units, the exercise you’re doing is vague intentionally so you can do it on your own. Some things to think about:
    Did you source your environment?
    Did you compile?
    Did you add the executable to CMakeLists.txt?
    Did you actually run the script with ros2 run?

  2. We actually offer a C++ course especially geared towards robotics. If you haven’t taken it, I highly recommend it:
    Learn Robotics from Zero - Robotics & ROS Online Courses

3

  1. I believe i did all the steps you mentioned above including ros2 run. It didn’t seems working. Btw, how can i delete the project and re-execute again? I will try again from scratch.

  2. I took the C++ course from Construct. Do you recommend any other cources?

4

Interestingly, it worked when i tried to launch the package this morning. The same ros2 run command did not worked other day.

Thanks for your response.

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