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matlabsimulinkequationodedifferential-equations

solve second order ODE in MATLAB/SIMULINK

I don't know how to solve this second order ODE in SIMULINK:

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I rewrote it to the system of first order ODEs:

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then

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giving

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My SIMULINK blocks are here:

SIMULINK blocks

giving this Scope:

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This is the plot of symbolic solution from dsolve:

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It looks like the functions (plots) from symbolic and SIMULINK are little similar.

Solution

  • The solution was found by Phil Goddard. His answer in comments:

    In Simulink you are plotting y_dot, while the symbolic solution is a plot of y.

    So the problem was that Scope was plotting the y'. The correct position of Scope is here:

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    giving the correct plot of y:

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    as you can see in the plot of symbolic solution:

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