Modeling, Simulating, and Analyzing Aircraft Flight Dynamics Using MATLAB and Simulink

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MODELING, SIMULATING, AND ANALYZING AIRCRAFT FLIGHT DYNAMICS USING MATLAB AND SIMULINK

By

Sebastian Suwisar 1-1111-046

BACHELOR’S DEGREE in

MECHANICAL ENGINEERING – MECHATRONICS CONCENTRATION FACULTY OF ENGINEERING AND INFORMATION TECHNOLOGY

SWISS GERMAN UNIVERSITY EduTown BSD City

Tangerang 15339 Indonesia

August 2015

Revision after the Thesis Defense on August 13^rd 2015

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Sebastian Suwisar STATEMENT BY THE AUTHOR

I hereby declare that this submission is my own work and to the best of my knowledge, it contains no material previously published or written by another person, nor material which to a substantial extent has been accepted for the award of any other degree or diploma at any educational institution, except where due acknowledgement is made in the thesis.

Sebastian Suwisar

____________________________________________

Student Date

Approved by:

Kirina Boediardjo, ST, M.Sc

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Thesis Advisor Date

Eka Budiarto, Ph.D

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Thesis Co-Advisor Date

Dr. Ir. Gembong Baskoro, M.Sc

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Dean Date

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FLIGHT DYNAMICS USING MATLAB AND SIMULINK

Sebastian Suwisar ABSTRACT

MODELING, SIMULATING, AND ANALYZING AIRCRAFT FLIGHT DYNAMICS USING MATLAB AND SIMULINK

By

Sebastian Suwisar

Kirina Boediardjo, ST, M.Sc, Advisor Eka Budiarto, Ph.D, Co-Advisor

SWISS GERMAN UNIVERSITY

Automatic flight control has long been applied to aircrafts to ease the work of pilot during a long duration of flight. To really understand about how to design an automatic flight control system, the needs of studying the flight dynamics model is very important. Therefore, it requires extensive research in building a flight dynamics model and analyzing flight performance before design an automatic flight control.

This thesis work's purpose is to develop a mathematical model for Boeing 737-300 aircraft, analyze the longitudinal flight dynamics, and optimize the performance of flight using PID controller. The flight condition to be analyzed is altitude control. PID controller is designed to fulfill the requirements for holding airspeed and holding altitude.

Initially, the aircraft geometry of Boeing 737-300 is imported to DATCOM and the aerodynamics coefficients of the aircraft are generated. These aerodynamics coefficients are imported to the mathematical model which is built in Simulink.

Finally, the simulation is performed in Simulink and graphs can be plotted to analyze the results.

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Sebastian Suwisar aerodynamics, and elevator aerodynamics system. Aircraft parameters and simulation's initial conditions are represented in the model.

The finding of this study shows that to automate the control of longitudinal flight dynamics model, it requires number of experiments in tuning the controller to finally achieve the desired condition for the output. It is also tested that in nonlinear model, static PID parameters has limited area of control.

Keywords: aircraft simulation, longitudinal flight dynamics, DATCOM, Simulink, PID controller.

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Sebastian Suwisar

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Sebastian Suwisar DEDICATION

I dedicate this works for Jesus Christ.

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Sebastian Suwisar ACKNOWLEDGEMENTS

For this completion of thesis, I would like to express my greatest gratitude to Jesus Christ. I would like to thank my advisor, Ms. Kirina Boediardjo for her support, guides, and consultation during these four months. I would like to thank my co- advisor, Mr. Eka Budiarto as well for guiding me through my thesis and helping me troubleshooting my problems throughout the entire process. For the information and guide for my thesis, I would like to thank also Mr. Pujianto Yugopuspito for his help and concern to my problems.

This thesis would not success without the greatest support from my loving family. I thank them for all the direct and indirect support to my thesis. I would like to thank Olivia Tamara for always supporting me for my thesis work.

Finally, I also place on record, my gratitude to all of my friends, especially Nico Adi Harianto, Felix Sanity Suparman, Putra Utama Jaya, Daniel Rinaldi Wijaya, Enzo Oestanto, Erin Erminda, Aldi Aldhira and all of my friends in mechatronics year 2011 for the help, the discussion, and our journey of friendship.

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Sebastian Suwisar TABLE OF CONTENTS

Page

STATEMENT BY THE AUTHOR ... 2

ABSTRACT ... 3

DEDICATION ... 6

ACKNOWLEDGEMENTS ... 7

TABLE OF CONTENTS ... 8

LIST OF FIGURES ... 11

LIST OF TABLES ... 13

CHAPTER 1 - INTRODUCTION ... 14

1.1 Background ... 14

1.2 Thesis Purpose ... 15

1.3 Thesis Problem ... 15

1.4 Thesis Scope ... 16

1.5 Thesis Limitation ... 16

1.6 Methodology ... 16

1.7 Thesis Organization ... 17

CHAPTER 2 - LITERATURE REVIEW ... 18

2.1 Boeing 737-300 Commercial Aircraft [1] ... 18

2.2 Review of Fundamental Theories ... 19

2.2.1 Longitudinal Flight Stability and Control [2] ... 19

2.2.2 PID Controller [3] ... 21

2.3 Software ... 23

2.3.1 DATCOM [4] ... 23

2.3.2 Matlab Simulink [5] ... 24

2.4 Previous Related Work ... 24

2.4.1 Automatic control education using FlightGear and Matlab based virtual lab [6] 24 2.4.2 3-DOF Longitudinal Flight Simulation Modeling and Design Using MATLAB/SIMULINK [7] ... 26

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Sebastian Suwisar

2.4.3 Aircraft Automatic Flight Control System Calculation [8]... 28

CHAPTER 3 - RESEARCH METHODS ... 30

3.1 Generating and Processing Aerodynamics Coefficients from DATCOM ... 31

3.1.1 Data Input to DATCOM [4] [9] ... 31

3.1.2 DATCOM Input Geometry Verification [10] ... 31

3.1.3 Aerodynamics Coefficients from DATCOM ... 32

3.2 Designing Longitudinal Flight Model in Simulink ... 36

3.2.1 Top Level Model ... 36

3.2.2 Aircraft Subsystem ... 37

3.2.3 Elevator Dynamics Subsystem ... 37

3.2.4 Aircraft Dynamics Subsystem ... 38

3.2.5 Main Body Aerodynamics Subsystem ... 41

3.2.6 Elevator Aerodynamics Subsystem ... 43

3.2.7 Body Coefficients Subsystem ... 44

3.2.8 Elevator Coefficient Subsystem ... 46

3.2.9 Environment Subsystem ... 47

3.3 Overview of PID Control in Longitudinal Flight Dynamics ... 48

CHAPTER 4 - RESULTS AND DISCUSSIONS ... 50

4.1 Model Troubleshooting ... 50

4.1.1 Incorrect Angle Unit Input ... 50

4.1.2 Incorrect Use of Axis Direction ... 50

4.1.3 Lag Response of the Simulation ... 51

4.2 Open Loop Response ... 51

4.3 Closed Loop Response ... 55

4.3.1 Airspeed Hold ... 55

4.3.2 Altitude hold ... 60

CHAPTER 5 - CONCLUSIONS AND RECCOMENDATIONS ... 63

5.1 Conclusions ... 63

5.2 Recommendations ... 64

GLOSSARY ... 65

References ... 66

Appendix A ... 67

Appendix B ... 71

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Sebastian Suwisar Appendix D ... 76 CURRICULUM VITAE ... 77