Doubt in building a set of equations using Simulink blocks

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Vicente 2015-3-9

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https://ww2.mathworks.cn/matlabcentral/answers/182310-doubt-in-building-a-set-of-equations-using-simulink-blocks

Hello.

I am struggling with building the following set of equations of the motion of a body in Simulink:

1) F1xr + F1xl + F2xr + F2xl = m*(vx' - psi'*vy) ; (sum of the forces in x direction) 2) F1yr + F1yl + F2yr + F2yl = m*(vy' + psi'*vx) ; (sum of the forces in y direction) 3) Ixx*psi" = a*(F1yl + F1yr) - b*(F2yl + F2yr) + (T1/2)*(F1xr - F1xl) + (T2/2)*(F2xr - F2xl) + Mz1 + Mz2 + Mz3 + Mz4; (sum of the moments around z axis)

This system is of a non-inertial reference frame, as seen by the acceleration components being written as a function of the rotational speed of the body, psi'. The question is reguarding how to build the connections between the various Simulink blocks, so that I may compute the body's accelerations, as they are interdependent. At first, I thouhgt of using an integrator block right out from the sum of moments around z (already divided by the corresponding moment of inertia), and using that output as the rotational speed of the body that would then lead to finding the linear accelerations in x and y. But I had doubts on how was I supposed to close the loop for those linear accelerations, knowing that they depend on their perpendicular velocities both... I mean, how can I close the loop on calculating ax if for it I must know vy, and vice-versa? Can someone please help me with this? Perhaps it might be more conveniet for me to use a state-space block just for these equations? And if so, how can I do so? Please, help.

Thank you.