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An Experimental Study on the Effects of Adverse Weathers on the Flight Performance of an Unmanned-Aerial-System (UAS)

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An Experimental Study on the Effects of Adverse Weathers on the Flight Performance of an Unmanned-Aerial-System (UAS) Iowa State University Capstones, Theses and Graduate Theses and Dissertations Dissertations 2021 An experimental study on the effects of adverse weathers on the flight performance of an Unmanned-Aerial-System (UAS) Muhammad Ahmad Siddique Iowa State University Follow this and additional works at: https://lib.dr.iastate.edu/etd Recommended Citation Siddique, Muhammad Ahmad, "An experimental study on the effects of adverse weathers on the flight performance of an Unmanned-Aerial-System (UAS)" (2021). Graduate Theses and Dissertations. 18615. https://lib.dr.iastate.edu/etd/18615 This Thesis is brought to you for free and open access by the Iowa State University Capstones, Theses and Dissertations at Iowa State University Digital Repository. It has been accepted for inclusion in Graduate Theses and Dissertations by an authorized administrator of Iowa State University Digital Repository. For more information, please contact [email protected]. An experimental study on the effects of adverse weathers on the flight performance of an Unmanned-Aerial-System (UAS) by Muhammad Ahmad Siddique A thesis submitted to the graduate faculty in partial fulfillment of the requirements for the degree of MASTER OF SCIENCE Major: Aerospace Engineering Program of Study Committee: Hui Hu, Co-Major Professor Abdelkhalik Ossama Omar, Co-Major Professor Ali Jannesari The student author, whose presentation of the scholarship herein was approved by the program of study committee, is solely responsible for the content of this thesis. The Graduate College will ensure this thesis is globally accessible and will not permit alterations after a degree is conferred. Iowa State University Ames, Iowa 2021 Copyright © Muhammad Ahmad Siddique, 2021. All rights reserved. ii DEDICATION I would like to dedicate this work to my parents, whose unwavering support and love throughout my life allowed me to accomplish wonders. iii TABLE OF CONTENTS Page ACKNOWLEDGMENTS ............................................................................................................. iv ABSTRACT ................................................................................................................................... vi CHAPTER 1. INTRODUCTION ....................................................................................................1 1.1 Types of weather conditions ................................................................................................ 8 1.2 Aircraft Icing ..................................................................................................................... 10 1.3 Effects of wind ................................................................................................................... 13 1.4 Wind estimation ................................................................................................................. 15 CHAPTER 2. DESIGN AND DEVELOPMENT OF THE UAS..................................................18 2.1 Selection of vehicle type .................................................................................................... 18 2.2 Air frame ............................................................................................................................ 18 2.3 Avionics ............................................................................................................................. 20 2.4 Propulsion .......................................................................................................................... 21 2.5 Communication and Tracking ........................................................................................... 21 2.6 Cameras ............................................................................................................................. 23 2.7 Sensors ............................................................................................................................... 24 2.8 Data Acquistion Unit ......................................................................................................... 26 CHAPTER 3. FLIGHT TESTING ................................................................................................29 3.1 UAS test experimentation site selection ............................................................................ 29 3.2 Experimental mission design ............................................................................................. 29 3.3 Weather station .................................................................................................................. 31 3.4 Type of data to be collected ............................................................................................... 32 CHAPTER 4. CALM CONDITIONS ...........................................................................................34 4.1 Calm condition flight ........................................................................................................ 34 4.1.1 Results ....................................................................................................................... 39 CHAPTER 5. WINDY CONDITIONS .........................................................................................51 5.1 Windy condition flight ...................................................................................................... 51 5.1.1 Results ....................................................................................................................... 52 CHAPTER 6. ICING CONDITIONS ............................................................................................63 6.1 Icing condition flight ........................................................................................................ 63 6.1.1 Results ....................................................................................................................... 65 CHAPTER 7. COMPARISON OF RESULTS AND DISCUSSION OF FINDINGS ..................81 iv CHAPTER 8. CONCLUSIONS AND RECOMMENDATIONS .................................................96 8.1 Recommendations for future work .................................................................................... 97 REFERENCES ..............................................................................................................................99 v ACKNOWLEDGMENTS I would like to express my sincerest gratitude to my advisors, Dr. Hui Hu and Dr. Ossama Abdelkhalik, for their guidance, support and patience throughout the course of this research without whom this research work would not be possible. I would also like to thank my committee member, Dr. Ali Jannesari for his insightful comments and suggestions on my research. Furthermore, I would like to extend a special thanks to my colleague Mr. Nianhong Han, whose technical insight helped me throughout my research work. I would also like to thank my colleagues in the Advanced Flow Diagnostics and Experimental Aerodynamics Laboratory, Mr. Ramsankar Veerakumar, Mr. Haiyang Hu, Mr. Zichen Zhang, Mr. Chukwudum Eluchie, and Ms. Abigayle Moser for their many fruitful discussions and assistance around the lab. I would also like to thank department faculty and staff, Mr. James Benson and Mr. Andrew Jordan, for their help with experimental facilities and Mrs. Marisa Mendoza for her constant assistance throughout my graduate program. Finally, I would like to thank my parents and my brothers Dr. Talal Siddique, Mr. Azhar Siddique and Dr. Nasir Siddique whose firm support and motivation helped me throughout the toughest phases of my graduate studies. Last, but not the least, I want to also offer my appreciation to my friends for staying by my side and making my experience at Iowa State University an unforgettable one. vi ABSTRACT An experimental UAS was developed to study the effects of adverse weathers, including icing and strong winds, on the UAS flight performance. Sensors were integrated on board the UAS to take in-situ, time-resolved measurements of atmospheric parameters, including temperature, humidity, pressure, wind direction and speed, during the flight. The measurement results of the atmospheric parameters were correlated with the UAS altitude data, and the UAS power consumption data to elucidate the underlying physics for a better understanding of the effects of the adverse weathers on the flight performances. Test flights were fully autonomous between takeoff and landing. The experimental portion of the flight had fixed geolocation and trajectories in the designed missions. The flights resulted in comparison of circular loiter data between calm, windy and icing conditions. Variations in the UAS power consumption were investigated during different segments of each flight. Glaze ice accretion was found to result in the malfunction of pitot static tube causing the loss of air speed data. Furthermore, wing leading edge and propeller icing resulted in rapid increase in the power consumption. It was discovered that ice accretion caused the greatest power consumption during the flight. Then, windy condition had the second highest power consumption with strong headwinds. Power consumption also spiked when turning against crosswinds from an initial tailwind condition. Iced propeller and vertical tail were preserved for the 3D scanning in the laboratory to quantify the 3-D shapes of the accreted ice structures. While the glaze icing on the UAS propeller resulted in the formation of ice horns and ridges, the main wing of the UAS had mostly leading-edge icing with the formation of runback rivulets
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