No topic /rrbot/joint2_position_controller

In unit4, we launch out self-implemented controller; however, after launching it, I cannot find the topic named /rrbot/joint1_position_controller. I thought there should be one though… Is that normal? Btw by robot in gazebo functioned correctly.
user:~$ rostopic list

Furthermore, for what I understood for the exercise in unit 4, we made a custom controller maintain the position of joint1 at position 1 rad, so if I modify this setting value, the robot should act differently, right? I tried but the robot acted the same as previously, is something wrong, or did just I misunderstand it?

Hello @yunjinli ,

Yes, this is normal because your controller is not providing this topic, it’s just setting the position of the joint to a specified value.

If you want to change the code and test it, you will need to restart the Gazebo simulation so that the new code is taken into account.