teleop_twist_keyboard in launch file has no output

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I'm trying to start the teleop_twist_keyboard node from within a launch file. I'm following the explanation at the bottom of this page: https://wiki.ros.org/stdr_simulator/T...

And this is my launch file:

<launch>
  <group ns="turtlesim">
    <node pkg="turtlesim" name="sim" type="turtlesim_node"/>
  </group>
  <node pkg="teleop_twist_keyboard" name="keyboard" type="teleop_twist_keyboard.py">
    <remap from="cmd_vel" to="turtlesim/cmd_vel"/>
  </node>
</launch>

It looks like this is launched correctly, however, I can't see the output of the teleop node and I'm not able to control the turtle.

Is there anything specific I should do to use the component? I'm guessing that roslaunch is not 'forwarding' my keyboard input to the right node, but I have no idea how to solve this.

update: I'm pretty new to ROS, so after investigating the topics and graph, it turns out I wasn't properly remapping the topic. This version of the teleop_twist_keyboard works, but I still don't have any output by the teleop_twist_keyboard node

  <node pkg="teleop_twist_keyboard" name="keyboard" type="teleop_twist_keyboard.py">
    <remap from="/cmd_vel" to="/turtlesim/turtle1/cmd_vel"/>
  </node>

So, still my question is, how can I have the teleop node output its text in the launch window.