flooding /cmd_vel with 0s doesnt stop the robot anymore

Karsten1987 / confbot_robot

workspace comprising demo packages for our roscon2018 talk

Apache License 2.0

10 stars 8 forks source link

flooding /cmd_vel with 0s doesnt stop the robot anymore #46

Closed mikaelarguedas closed 5 years ago

mikaelarguedas commented 5 years ago

Running the "Compromise the system" section, I'm publishing at 100Hz on cmd_velocity: ros2 topic pub /cmd_vel geometry_msgs/Twist "linear: {x: 0}" -r 100

But the robot keeps rotating in circle as if no messages were sent.

If I unload the twist_publisher component, I can then publish on /cmd_vel and command the robot

Karsten1987 commented 5 years ago

I can confirm that zero does indeed not stop the robot as the twist publisher keeps the robot moving. However, in terms of security demo, when publishing

ros2 topic pub /cmd_vel geometry_msgs/Twist "linear: {x: 0.5}, angular: {z: 0.5}" -r 10

the robot does speed up tremendously. So that can be used as usual for visualization.

mikaelarguedas commented 5 years ago

Great!

I added https://github.com/Karsten1987/roscon2018/pull/43/commits/a422587f66f1404a5b17cf10169c6e2ead5b58b2 to use this pattern and make the robot go backward

Thanks!