1 Matlab Simulink Tutorial 1 -1st Order System

8/3/2019 1 Matlab Simulink Tutorial 1 -1st Order System

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A Simulink tutorial

Getting Started with Matlab Simulink


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Controls and Instrumentation Slide 2

Before we start

You should have access to Matlab andSimulink software through the laboratorycomputers in Fryklund Hall.


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Controls and Instrumentation

[All Program] Matlab Launch Simulink

Slide 3

Launch Matlab Simulink


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Create a new model

Click the new-modelicon in the upper left

corner to start a newSimulink file

Select and expand theSimulink icon to obtainelements of the model

Create a new model from the Simulink Library window Browser


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Workspace in Simulink

Library of elements Model is created in this window


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Save your Model

You might create anew folder to save

your Simulink files.

The saved Simulinkfiles should have .mdlsuffix with the file

names.


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Example 1: A Simple Model

Build a Simulink model that solves the differentialequation

Initial condition:

The analytical solution

First, sketch a block diagram of this mathematical

model (equation) in Simulink.

( ) ( ) 0y t y t

( ) 0.01 t 0t

y t e

y(0) = 0.01


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Controls and InstrumentationMFGE 363 Slide 8

Block Diagram in Simulink

The differential equation:

Output is the solution of the differential equationy (t)

( ) ( ) 0y t y t

yy

s

10

(input)

y (t)

(output)

(0) 0.01y

integrator


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Block Diagram in Simulink

First, solve for the term with highest-orderderivative

Make the left-hand side of this equation theoutput of a summing block as shown in the blockdiagram on the next slide

( ) 0 ( )y t y t


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Block Diagram for the DEQ

( ) ( ) 0 can be re-arrange as

( ) 0 ( )

y t y t

y t y t

( )y t ( )y t


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Select an Input Block

Drag a Constant block fromthe Sourceslibrary to themodel window


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Select a SUM Block

Drag a SUM block from theMath Operationslibrary tothe model window

Math Operations


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Select an Integrator Block

Drag an Integratorblockfrom the Continuouslibraryto the model window


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Select a Scope Block

Drag a Scopeblock from theSinkslibrary to the modelwindow


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Select a Gain Block

Drag a Gain block from theMath Operationlibrary to themodel window


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Connect Blocks with Signals

Place your cursor on theoutput port (>) of theConstantblock

Left click the mouse and

drag from the Constantoutput port to the Suminput

Drag from the SUMoutput to the input of

the integrator input port Connect the scope and

gain blocks

Arrows indicate the directionof the signal flow.


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Select Simulation Parameters

Double-click on theConstantblock to setConstant value = 0.


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Change the sign of thesum block to +- in thefield of List of signs


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Double-click onthe Gain block toset gain = 1.


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Double-click on theScopeto view thesimulation results


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Run the Simulation

In the modelwindow, from theSimulationpull-down menu, selectStart


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View the Simulation

Click on Auto-scale andview the output y (t)inthe Scopewindow. Auto scale


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Simulation Results

To verify that this plotrepresents the solution tothe problem, solve the

equation analytically.

The analytical result,

matches the plot (thesimulation result) exactly.

( ) 0.01 t 0t

y t e

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1 Matlab Simulink Tutorial 1 -1st Order System