PWM extraction and modification

Hey Everyone,

I’m currently trying to obtain the PWM signal that my Pixhawk4 outputs to the ESC’s in order to apply a noise (produced by the motors and rotors) prediction calculation on board the FC. It is my first time doing a project like this and i am struggling to find the appropriate procedure to obtain this information, I have tried using the uORB messaging (doesn’t seem to have PWM info) and commands (pwm command-cant get to work).

A nudge in the right direction would be great as i feel as though i have read the PX4 user guide 100 times over and still cant apply the correct procedure.