Understanding/Modification Iris Model

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I am new to the px4/gazebo, and tried a lot of internet searching but couldn’t get a proper answer. I am trying to modify the IRIS model physical parameters e.g, changing the thrust of iris motors, changing the size of the propeller, according to my drone parameters, etc, for that, I need to change physically as well as control parameters to have a balanced flight. Can you please help me to clarify which parameters do I need to change, sdf file for iris is of 700 lines and how can I understand the whole file. Is there any description/explanation for the file so that I can have a proper understanding? Also, after modification in physical parameters, which areas in px4 do I need to change so that I can have a proper flight without and imbalances? any suggestion, guidance will be much appreciated.

Regards,

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@n.tufail If you are trying to understand the sdf file, you can have a look on some tutorials: http://gazebosim.org/tutorials?tut=build_model or look at the sdf specification itself: http://sdformat.org/spec

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Thanks for the response, yes your reply helped me in a way, and am already following tutorials, but my question is where could I make changes in the px4/sitl_gazebo models to set parameters of the drone according to my own drone’s parameters? In the end, I want to simulate a drone, which has parameters like weight , inertia, rotors parameters like thrust, revolution per minute, etc based on my design?

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@n.tufail Yes, you can configure them in the sdf file, for e.g. you have the <intertial> tag for the intertial parameters - which is explained in the sdf specifications

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ok, so for the tag in the SDF file, is there any guidance for calculating the iris inertia? I know they have already used the values, but how did they manage to calculate the inertia for the whole iris drone? There is a wiki guide to calculate the inertias for simple shapes. I couldn’t calculate the inertia for the whole drone…! I have seen posts giving formulas for calculating

maxRotVelocity
motorConstant
momentConstant
rotorDragCoefficient
but still can’t find any proper way to calculate inertia for the iris drone or the drone that has parameters according to my own specifications.

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@n.tufail Moment of Inertia is a physical property, and you measure it and not calculate. If you want to guess it, you can try and calculate it.

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If you still need to know the iris inertia calculation, you can find its equations in the file with this directory:
Tools/sitl_gazebo/models/rotors_description/urdf/iris.xacro

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Hello,
I wanted to ask that I am trying to find the file of rotors_description, but it has been removed in the Firmware folder. What to do??
I actually want to add a component that I have designed in Fusion 360 to the iris model. How to integrate these two things ??