DEVELOPMENT, ANALYSIS, AND IMPLICATIONS OF OPEN-SOURCE SIMULATIONS OF REMOTELY PILOTED AIRCRAFT by © Oihane Cereceda Cantarelo, B.Eng., M.Eng. A Doctoral Thesis submitted to the School of Graduate Studies In partial fulfillment of the requirements for the degree of Doctor of Philosophy Faculty of Engineering and Applied Science Memorial University of Newfoundland February 2020 St. John’s Newfoundland and Labrador Abstract In recent years, the use of Remotely Piloted Aircraft (RPAs) for diverse purposes has increased exponentially. As a consequence, the uncertainty created by situations turning into a threat for civilians has led to more restrictive regulations from national administrations such as Transport Canada. Their purpose is to safely integrate RPAs in the current airspace used for piloted aviation by evaluating Sense and Avoid (SAA) strategies and close encounters. The difficulty falls on having to rely on simulated environments because of the risk to the human pilot in the piloted aircraft. In the first part of this research, the technical difficulties associated with the development and study of RPA computer models are discussed. It explores the rationale behind using Open- Source Software (OSS) platforms for simulating RPAs as well as the challenges associated with interacting with OSS at graduate student level. A set of recommendations is proposed as the solution to improve the graduate student experience with OSS. In the second part, particular challenges related to the design of OSS computer models are addressed. Based on: (1) the differences and similarities between piloted and RPA flight simulators and (2) existing Verification and Validation (V&V) approaches, a validation method is presented as a solution to the subject of developing fixed-wing RPAs in OSS environments. This method is used to design two flight dynamics models with SAA applications. The first computer model is presented in tutorial format as a case study for the validation procedure whereas the second computer model is specific for testing SAA strategies. In the last part, one of the designed RPAs is integrated into a computer environment with a representative general i aircraft. From the simulated encounters, a diving avoidance manoeuvre on the RPA is developed. This performance is observed to analyze the consequences to the airspace. The implications of this research are seen from three perspectives: (1) the OSS challenges in graduate school are wide-spread across disciplines, (2) the proposed validation procedure is adaptable to fit any computer model and simulation scenario, and (3) the simulated OSS framework with an RPA computer model has served for testing preliminary SAA methods with close encounters with manned aircraft. ii Acknowledgements This thesis is dedicated to my parents, Luis Cereceda and Adelina Cantarelo, who always believed in my potential and made from me the person that I am today. To my family and dear friends, who encouraged me to stay strong during the most challenging times. This research would not have been possible without the financial support of the InnovateNL of Tourism, Culture, Industry and Innovation, Newfoundland and Labrador as part of the ArcticTECH research program. I would like to express my sincere gratitude to my supervisors, Dr. Siu O’Young and Dr. Luc Rolland, for their continuous support and assistance during my PhD program. Their motivation and knowledge were vital. I would also like to thank the rest of my thesis committee for their insightful comments and encouragement. I would like to express my very great appreciation to Dr. Itziar Cabanes and her team at the University of the Basque Country (UPV/EHU) during my research stay in the Faculty of Engineering in Bilbao. She is a true inspiration and her support and help were invaluable. During my program, I have worked with many brilliant graduate students who have been crucial in defining and developing this thesis. I am especially grateful to Danielle Quinn, with whom I shared countless discussions that contributed to shaping one of the chapters of this thesis. I thank my fellow colleagues Iryna Borshchova, Bruno Artacho, and Robert MacIsaac for the stimulating discussions and guidance they provided in the periods when I had lost all confidence. The various groups I have been involved with at Memorial University have become my second family. I want to thank each and every single one of the people I met through the MUN Mentors iii Program and Women in Science and Engineering Graduate Student Society for their encouragement aside of my research work, without which I could not have succeeded. Finally, this thesis would have not been possible without the unconditional support, patience and dedication of my partner, Dave Noseworthy, who was always there to cheer me up and encourage me to be positive. iv Table of Contents Abstract ........................................................................................................................................... i Acknowledgements ...................................................................................................................... iii Table of Contents .......................................................................................................................... v List of Figures ............................................................................................................................... ix List of Tables .............................................................................................................................. xiii List of Abbreviations .................................................................................................................. xv List of Appendices .................................................................................................................... xviii Chapter 1. Introduction ............................................................................................................... 1 1.1. Context of the Remotely Piloted Aircraft Systems Problem............................................ 2 1.2. The Relevance of Simulated Frameworks for Testing SAA Methods ............................. 5 1.3. Objectives of this Research .............................................................................................. 6 1.3.1. Application Scope ......................................................................................................... 8 1.3.2. Out of Scope .................................................................................................................. 9 1.4. Significance .................................................................................................................... 10 1.5. Thesis Outline ................................................................................................................ 11 Chapter 2. Background .............................................................................................................. 13 2.1. Remotely Piloted Aircraft: Definition, Context, and Requirements .............................. 14 2.2. Simulation Platforms: JSBSim and FlightGear .............................................................. 19 2.2.1. Existing Open-source FDM ......................................................................................... 20 2.2.2. JSBSim Open-source FDM ......................................................................................... 23 2.2.3. FlightGear Flight Simulator .................................................................................... 26 2.3. Theoretical Background: JSBSim FDM ........................................................................ 26 2.3.1. Frames of Reference ............................................................................................... 27 v 2.3.2. Forces and Moments ............................................................................................... 28 2.3.3. Equations of Motion ............................................................................................... 31 2.3.4. Propulsion ............................................................................................................... 33 2.3.5. Flight Control .......................................................................................................... 34 2.4. Computer Model Development ...................................................................................... 35 2.4.1. Validation methods for RPAs ...................................................................................... 40 2.5. Sense and Avoid Basis ................................................................................................... 41 2.5.1. Scope of the SAA application ..................................................................................... 42 2.6. Summary ........................................................................................................................ 43 Chapter 3. Open-Source Software in Aerospace with RPA Applications: Challenges and Solutions ....................................................................................................................................... 44 3.1. Basic Flight Simulator Framework ................................................................................ 45 3.2. Technical challenges of working on/with OSS in Academia ......................................... 48 3.2.1. Software in the Scientific World ............................................................................