Send a "backflip" command

Hi there, 

thanks for the nifty hacks.

I am struggling with the "backflip" command. I was able to execute from the joystick, but can't figure out how to send this command over UDP or mosquitto. The following didn't work `mosquitto_pub -h <HOST> -d -t "controller/action" -m "backflip"`.

Can you suggest something?