Drone dynamics or Mathematical model in SITL

Hi everyone!

I am running a simulation of a drone on gazebo using mavros and I would like to know if I can access the equations of motion of the drone (dynamics) in one way or another, so I can do some modifications. I would like also to know where can I find the motors simulation model for example: the mechanical and electrical equations and their coupling. I have been searching for a very very long time and I didn’t find any answers. Thank you very much for your help in advance.

You can take a look here at some diagrams:

The code you are looking for is librarires/SITL