I am using roscontrol with robotis arms (github). I want to know how to check the status of the `controllermanager. Because I found that even if thecontroller_managerdies, thewrite` is still executed which could lead to improper data being written.

I encountered this when I used <node name="ros_control_controller_manager" pkg="controller_manager" type="controller_manager" respawn="false" output="screen" args="load pos_based_pos_traj_controller" /> in my launch file. The controller would load and then stop, but the write would be writing zero to the hardware.

So how can I overcome this problem or is this a invalid concern?

Also how do you check whether system has initialized properly, so that you can write. As when you initialize the system for the first time, I have only zeros in the position_cmd variable used to write to the hardware for certain period of time.