System modelling

[MichaelkSA]

I have to model a system that is very similar to that shown in the attached image. Without the inclination I know my state variables are Delta, v_1 and v_2 and I know I want to model the inclination Theta as a disturbance. How should by state eqn's look?

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Here's looking at you, looking at me, looking at you

 

[FeX32]

Is this for school? If you sum forces you will end up with the horizontal components simply being multiplied by cos(theta)