F-14 Longitudinal Model
NOTE: You will need to have an installed and functioning version of MATLAB® and Simulink® to run this example.
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Initialization
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| (1.1) |
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Import the System
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We import the model with the following command. We need to specify the name of the model to import, as well as a MATLAB script that initializes the variable names.
Using the Summary command, we can view the model that we have imported.

| (2.1) |
We can now simplify the model to reduce the number of equations.

| (2.2) |
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Simulate the System
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First we take the system and build a set of differential equations, and assign the result to the variable sys.
| (3.1) |
The following table illustrates the different components of the variable sys1.
Differential Equations

| (3.2) |
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Parameter values

| (3.3) |
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Initial conditions
 = 0, x[15, 1](0) = 0, x[16, 1](0) = 0, x[25, 1](0) = 0, x[26, 1](0) = 0, x[26, 2](0) = 0, x[32, 1](0) = 0, x[33, 1](0) = 0, x[35, 1](0) = 0, x[37, 1](0) = 0]](/support/helpjp/helpview.aspx?si=8296/file07818/math443.png)
| (3.4) |
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Equations for the sources (inputs)
| (3.5) |
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List of sinks (outputs)
| (3.6) |
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Using the information in the variable sys, we construct a simulation procedure.
| (3.7) |
Then we plot the simulation results.
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Import the Subsystem
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First we want to close the Simulink model without saving it, so we can reload it with the subsystem. We send the command close_system('m_f14', 0) through the link to MATLAB.
We can import a subsystem from the model.
The set of equations are simplified and the simplified set of equations is printed using the PrintSummary command.
![[K[0, "Md"] = -6.88469999999999960, K[0, "Mq"] = -.657100000000000018, K[0, "Mw"] = -0.591999999999999992e-2, K[0, "Uo"] = 689.399999999999976, K[0, "Zd"] = -63.9979000000000014, K[0, "Zw"] = -.638499999999999958]](/support/helpjp/helpview.aspx?si=8296/file07818/math738.png)
| (4.1) |
The differential equations are created.
| (4.2) |
The following table illustrates the different components of the variable sys2.
Differential Equations
 = x[12, 1](t)/K[0, "Uo"], diff(x[12, 1](t), t) = K[0, "Zd"]*u[1, 1, 1](t)-u[1, 2, 1](t)+K[0, "Uo"]*y[1, 2, 1](t)+K[0, "Zw"]*x[12, 1](t), diff(x[13, 1](t), t) = K[0, "Mw"]*x[12, 1](t)-u[1, 3, 1](t)+K[0, "Md"]*u[1, 1, 1](t)+K[0, "Mq"]*x[13, 1](t), y[1, 2, 1](t) = x[13, 1](t)]](/support/helpjp/helpview.aspx?si=8296/file07818/math803.png)
| (4.3) |
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Parameter values
![[K[0, "Md"] = -6.88469999999999960, K[0, "Mq"] = -.657100000000000018, K[0, "Mw"] = -0.591999999999999992e-2, K[0, "Uo"] = 689.399999999999976, K[0, "Zd"] = -63.9979000000000014, K[0, "Zw"] = -.638499999999999958]](/support/helpjp/helpview.aspx?si=8296/file07818/math843.png)
| (4.4) |
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Initial conditions
| (4.5) |
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Equations for the sources (inputs)
| (4.6) |
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List of sinks (outputs)
| (4.7) |
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